WO2025064876A1

WO2025064876A1 - Retrogradation-resistant starch and method of making

Info

Publication number: WO2025064876A1
Application number: PCT/US2024/047768
Authority: WO
Inventors: John K. TYNAN JR.; Nathan I. ISSER; Janis Gunars Matisons
Original assignee: Intertape Polymer Corp
Current assignee: Intertape Polymer Corp
Priority date: 2023-09-20
Filing date: 2024-09-20
Publication date: 2025-03-27
Anticipated expiration: 2026-03-20

Abstract

This disclosure is directed to a retrogradation resistant starch film and a continuous, process for the compounding and extruding of the starch film and/or preparing laminates. In one aspect of the disclosure, the starch may be applied directly as a web, film, or layer as a reinforcement, for example, in a tape product, air pillow, or mailer.

Description

RETROGRADATION-RESISTANT STARCH AND METHOD OF MAKING

Technical Field

[0001] This disclosure is directed to starch films and a process for the compounding of starch and the production of starch pellets or films, in particular, retrogradation-resistant starch comprising pellets or films.

BACKGROUND

[0002] Conventional packaging materials such as air cushions, can be made or contain considerable amounts of polyolefins, the polyolefins being often petroleum-based polyolefins. With changing global trends facing most industries, due to environmental concerns regarding greenhouse gas emissions and high dependency on depleting petroleum-based resources, a strong sustainability strategy for creating better, more environmentally responsible packaging that is compostable, biodegradable, circular, recyclable and/or repulpable is desired.

SUMMARY

[0003] In examples, a retrogradation-resistant starch comprising pellets or film is provided, the film comprising a starch and an amount of molecular weight modifier.

[0004] In one aspect, the starch is derived from cassava, corn, potato, sweet potato, sago, tapioca, sorghum, bean, bracken, lotus, Trapa japonica, wheat, rice, oat, arrowroot, dent, or pea. In one aspect, alone or in combination with any of the previous aspects, the starch present in the film is glutinous rice, waxy potato starch, and waxy corn.

[0005] In one aspect, alone or in combination with any of the previous aspects, the starch comprises an amylose to amylopectin weight ratio between 40:60 to 0:100.

[0006] In one aspect, alone or in combination with any of the previous aspects, the starch comprises a blend of starches with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100.

[0007] In one aspect, alone or in combination with any of the previous aspects, the starch comprises a modified starch with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100. [0008] In one aspect, alone or in combination with any of the previous aspects, the starch is a blend of modified starches with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100.

[0009] In one aspect, alone or in combination with any of the previous aspects, the starch present in the film is a starch, a thermoplastic starch, an alkyl etherized starch, carboxyalkyl etherized starch, hydroxyalkyl etherized starch having a hydroxyalkyl group having 2 to 6 carbon atoms, and synthetic starches.

[0010] In one aspect, alone or in combination with any of the previous aspects, the starch comprises a combination of a first starch having an amylose to amylopectin weight ratio between 40:60 to 0:100 and a second starch having an amylose to amylopectin weight ratio between 40:60 to 0:100, where at least one of the first starch and the second starch, independently, is unmodified, modified, synthetic, thermoplastic, or crosslinked.

[0011] In one aspect, alone or in combination with any of the previous aspects, the molecular weight modifier is one or more of modified microfibrillated celluloses, nanofibrillated celluloses, modified nanofibrillated celluloses, sugar alcohols, dextrins, maltodextrins, synthetic and natural layered silicate clays, montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof.

[0012] In one aspect, alone or in combination with any of the previous aspects, the molecular weight modifier is one or more of a least partially exfoliated or a least partially intercalated montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof. Graphene oxide/ surface modified nanosilicate BELSIL® REG 1103B (Wacker).

[0013] In one aspect, alone or in combination with any of the previous aspects, the molecular weight modifier is one or more of montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, and volkonskoite, in combination with a surfactant, an anionic surfactant, a zwitterionic compound, a zwitterionic polymer or copolymer, a polyampholyte compound, a polyampholyte polymer, urea or combinations thereof. [0014] In one aspect, alone or in combination with any of the previous aspects, the weight ratio of the starch to the molecular weight modifier is between 50:1 to 1:50.

[0015] The retrogradation-resistant starch comprising pellets or of any one of the previous claims, further comprising glycerol, polyvinyl alcohol, polyvinyl alcohol copolymer, polyvinyl pyrrolidone, polyacrylamide (PAM), poly acrylic acid (PAA), cellulose derivatives, alginate, chitosan or combinations thereof.

[0016] The retrogradation-resistant starch comprising pellets or of any one of the previous claims, further comprises one or more components selected from the group consisting of impact modifiers, plasticizers, plasticizer compatibilizers, lubricants, release agents, fillers (e.g. wood flour), extenders, cross-linking agents, antiblocking agents, antioxidants, detackifying agents, antifoams, nanoparticles, bleaching agents, biocides, antimicrobials, surfactants, pigments, and combinations or reaction products thereof.

[0017] In another example, a sustainable fluid-fillable air cushion is provided, the air cushion comprising the retrogradation-resistant starch film of any one of the previous aspects. In another example, a repupable mailer is provided, the mailer comprising the retrogradation-resistant starch film as defined in any one of the previous aspects.

[0018] In another example, a process for producing a retrogradation-resistant starch comprising pellets or film composition is provided, comprising continuously or semi- continuously metering into a low shear extrusion equipment a composition comprising a starch, modified starch, thermoplastic starch, or combination, a molecular weight modifier, a PVOH polymer or copolymer, continuously mixing the composition in a compounding section of the low shear extrusion equipment, and continuously discharging a retrogradation-resistant starch film from the extruder.

[0019] In one aspect, the method further comprises adding at least one of glycerol and water to the composition in the compounding section. In one aspect, alone or in combination with any of the previous aspects, the water is liquid, steam, or a combination of liquid and steam.

[0020] In one aspect, alone or in combination with any of the previous aspects, the molecular weight modifier is one or more of at least partially exfoliated or at least partially intercalated montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof.

[0021] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is one or more of at least partially exfoliated or at least partially intercalated bentonite salt of an alkaline metal, alkaline earth metal, and combinations thereof..

[0022] In one aspect, the method further comprises continuously producing a film from the mixture and contacting the film to the second major surface of the repulpable backing.

[0023] In one aspect, alone or in combination with any one of the previous aspects, the high solids continuously or semi-continuously mixing is of a high solids content of the starch, where the high solids includes from 25 weight percent to 75 weigh percent of the starch.

[0024] In one aspect, alone or in combination with any one of the previous aspects, the method further comprising heating the pellets to a flowable state, producing a film from the melt, and extrusion laminating the film to the second major surface of the repulpable backing.

[0025] In one aspect, alone or in combination with any one of the previous aspects, the method further comprises remelting the pellets to a melt, producing a film from the melt, extrusion laminating the film.

[0026] In one aspect, alone or in combination with any one of the previous aspects, the total amount of the state of water added is 10 to 50% by mass of the mixture. In one aspect, alone or in combination with any one of the previous aspects, the state of water is liquid, steam, or a combination of liquid and steam.

[0027] In one aspect, alone or in combination with any one of the previous aspects, during the mixing, the heating is performed at a temperature less than less than 150 °C, less than 140 °C, less than 135 °C, or less than 130 °C.

[0028] In one aspect, alone or in combination with any one of the previous aspects, the mixture is extruded as a continuous web, film, or layer. In one aspect, alone or in combination with any one of the previous aspects, the extrudate is extruded using a spinnerette die, slot-die, annular die, co-extruded die or combinations thereof.

[0029] In one aspect, alone or in combination with any one of the previous aspects, the method further comprises adding additional materials to the mixture. In one aspect, alone or in combination with any one of the previous aspects, the additional materials comprise solid raw materials selected from the group consisting of impact modifiers, tackifying resins, extenders, activators, crosslinkers, colorants, recycled waste plastic, recycled cellulosic material, microfibrillated cellulose, nanofibrillated cellulose, clays, for example, bentonite, and mixtures thereof in any proportions. In one aspect, alone or in combination with any one of the previous aspects, the secondary materials comprise recycled material. In one aspect, alone or in combination with any one of the previous aspects, the additional materials further comprise an activator selected from the group consisting of zinc oxide, azide, epoxide, sodium tetraborate, magnesium oxide and combinations thereof and an extender selected from the group consisting of clays, calcium carbonate, talc, aluminum hydrates and combinations thereof.

[0030] In one aspect, alone or in combination with any one of the previous aspects, the modified starch is a thermoplastic starch or derivatized starch.

[0031] In one aspect, alone or in combination with any one of the previous aspects, the starch is derived from cassava, corn, potato, sweet potato, sago, tapioca, sorghum, bean, bracken, lotus, Trapa japonica, wheat, rice, oat, arrowroot, dent or pea. In one aspect, alone or in combination with any one of the previous aspects, the repulpable reinforcement comprises glutinous rice, waxy potato starch, and waxy corn.

[0032] In one aspect, alone or in combination with any one of the previous aspects, the starch comprises a blend of starches with a combined weight ratio of amylose to amylopectin between 40:60 and 0:100. In one aspect, alone or in combination with any one of the previous aspects, the starch comprises a modified starch with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100. In one aspect, alone or in combination with any one of the previous aspects, the starch is a blend of modified starches with a combined weight ratio of amylose to amylopectin between 40:60 and 0:100. In one aspect, alone or in combination with any one of the previous aspects, the starch comprises a combination of a first starch having an amylose to amylopectin weight ratio between 40:60 and 0:100 and a second starch having an amylose to amylopectin weight ratio between 40:60 and 0:100, where at least one of the first starch and the second starch, independently, is unmodified, modified, synthetic, or crosslinked. [0033] In one aspect, alone or in combination with any one of the previous aspects, the starch further comprises at least one repulpable material, the weight ratio of the starch to any one or all of the at least one water-soluble material is between 50:1 to 1:50.

[0034] In one aspect, alone or in combination with any one of the previous aspects, the starch or a modified starch comprises an amount of polyvinyl alcohol or polyvinyl alcohol copolymer. In one aspect, alone or in combination with any one of the previous aspects, the starch or a modified starch comprises an amount of polyvinyl alcohol and a polyvinyl alcohol copolymer. In one aspect, alone or in combination with any one of the previous aspects, the starch or a modified starch comprises an amount of polyvinyl alcohol and a polyvinyl alcohol copolymer. In one aspect, alone or in combination with any one of the previous aspects, the starch or a modified starch comprises an amount of polyvinyl alcohol or polyvinyl alcohol copolymer having a saponification degree of 80 to 99.8 mol %.

[0035] In one aspect, alone or in combination with any one of the previous aspects, the starch or a modified starch comprises an amount of polyvinyl alcohol and/or polyvinyl alcohol copolymer comprising one or more anionic monomers. In one aspect, alone or in combination with any one of the previous aspects, the one or more anionic monomer are independently selected from the group consisting of vinyl acetic acid, maleic acid, monoalkyl maleate, dialkyl maleate, monomethyl maleate, dimethyl maleate, maleic anhydride, fumaric acid, monoalkyl fumarate, dialkyl fumarate, monomethyl fumarate, dimethyl fumarate, fumaric anhydride, itaconic acid, monomethyl itaconate, dimethyl itaconate, itaconic anhydride, vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2- acrylamido-l-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2- methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali metal salts of the foregoing, esters of the foregoing, and combinations thereof.

[0036] In another example, a process for producing a retrogradation-resistant starch film composition is provided, the process comprising: continuously or semi-continuously metering into a mixing or extrusion equipment a starch film composition comprising a starch, modified starch, thermoplastic starch, or combination thereof, and a molecular weight modifier; continuously mixing the composition in the mixing or extrusion equipment; and continuously, semi-continuously, or batchwise discharging a retrogradation-resistant starch film. [0037] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is selected from one of or a combination of one or more of modified microfibrillated celluloses, nanofibrillated celluloses, modified nanofibrillated celluloses, sugar alcohols, dextrins, maltodextrins, clays, exfoliated and/or intercalated clays, e.g., exfoliated and/or intercalated bentonite, biocides, humectants, extenders, crosslinking agents. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is selected from synthetic and natural layered silicate clays such as montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and a mixture thereof. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is selected from exfoliated and/or intercalated synthetic and natural layered clays. By way of example, bentonite clays is discussed hereinafter as exemplary of the above synthetic and natural layered exfoliated and/or intercalated clays. [0038] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier provides intercalated (nano)composites of clay and starch, where (nano)composites is used herein to encompass nanocomposites and/or composites of larger size. In one aspect, alone or in combination with any one of the previous aspects, nanocomposites of clay and starch are provided. In one aspect, alone or in combination with any one of the previous aspects, nanocomposites of clay and starch in combination with composites of clay and starch are provided.

[0039] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier provides exfoliated (nano)composites of clay and starch. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier provides intercalated (nano)composites of clay and starch in combination with exfoliated (nano)composites of clay and starch at a ratio of 0:100 to 100:0, or 1:99 to 99:1. [0040] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is modified prior to compounding or mixing with the starch. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is exfoliated and/or intercalated prior to compounding or mixing with the starch. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is modified during compounding or mixing with the starch. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is exfoliated and/or intercalated during compounding or mixing with the starch. [0041] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is combined with one or more processing aide before or during compounding or mixing with the starch so as to assist or provide intercalation or exfoliation of the molecular weight modifier. In one aspect, alone or in combination with any one of the previous aspects, the one or more processing aids is a surfactant, an anionic surfactant, a zwitterionic compound, a zwitterionic polymer or copolymer, polyampholyte compounds, polyampholyte polymers, or urea. Other processing aids can be employed to effect the formation of (nano)composites of clay and starch.

[0042] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is exfoliated and/or intercalated bentonite. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is exfoliated and/or intercalated calcium bentonite. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is exfoliated and/or intercalated bentonite in combination with urea. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is exfoliated and/or intercalated calcium bentonite in combination with urea.

[0043] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of bentonite so as to provide a particle size of between about 10 microns to about 0.1 microns. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of calcium bentonite so as to provide a particle size of between about 10 microns to about 0.1 microns. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of bentonite in combination with urea so as to provide a particle size of between about 10 microns to about 0.1 microns. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of calcium bentonite in combination with urea so as to provide a particle size of between about 10 microns to about 0.1 microns. [0044] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of bentonite in combination with urea at a weight ratio of 10:1 to 1:10, 5:1 to 1:5, 3:1 to 1:3, 2:1 to 1:2, or 1:1. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of calcium bentonite in combination with urea at a weight ratio of 10:1 to 1:10, 5:1 to 1:5, 3:1 to 1:3, 2:1 to 1:2, or 1:1.

[0045] In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of calcium bentonite in combination with urea at a weight ratio of 10:1 to 1:10, 5:1 to 1:5, 3:1 to 1:3, 2:1 to 1:2, or 1:1 before compounding or mixing with the starch. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of calcium bentonite in combination with urea at a weight ratio of 10:1 to 1:10, 5:1 to 1:5, 3:1 to 1:3, 2:1 to 1:2, or 1:1 before compounding or mixing with the starch, where the weight percent of the calcium bentonite in combination with urea is 20%, 15%, 10%, 7%, 5%, 4%, 3%, 2%, 1% or about 0.5% to 0.1% of the total weight of starch-molecular weight modifier composition on a dry weight basis. In one aspect, alone or in combination with any one of the previous aspects, the molecular weight modifier is a sonicated and/or milled suspension of calcium bentonite in combination with urea at a weight ratio of 10:1 to 1:10, 5:1 to 1:5, 3:1 to 1:3, 2:1 to 1:2, or 1:1 before compounding or mixing with the starch, where the weight percent of the calcium bentonite in combination with urea is between 20%, 15%, 10%, 7%, 5%, 4%, 3%, 2%, 1% or about 0.5% to 0.1% of the total starch mass in the composition.

[0046] In one aspect, alone or in combination with any one of the previous aspects, the starch-molecular weight modifier composition discharged from the extrusion equipment has a measured molecular weight that is reduced less than 50% reduced less than 40%, reduced less than 30%, reduced less than 20%, reduced less than 10% compared to the measured molecular weight of the starch prior to extrusion, as measured by Asymmetric Flow Field Fractionation (AF4), Low-Angle Laser Light Scattering (LALLS), or Multi-Angle Laser Light Scattering (MALLS), GPC, or viscosity measurements. [0047] In one aspect, alone or in combination with any one of the previous aspects, the starch-molecular weight modifier composition discharged from the extrusion equipment has measured molecular weight of the starch is increased more than 10%, more than 20%, more than 30%, more than 40%, more than 50%, more than 60%, more than 70%, more than 80%, more than 90%, more than 100%, more than 125%, more than 150%, more than 200%, more than 250%, more than 300%, more than 350%, more than 400%, more than 450%, or more than 500% up to 1000% of measured molecular weight of the starch prior to extrusion, as measured by asymmetric flow field fractionation (AF4), low-angle laser light scattering (LALLS) or multi-angle laser light scattering (MALLS), GPC or viscosity by the presently disclosed method. While not to be held to any particular theory, the increase in measured asymmetric flow field fractionation (AF4), low-angle laser light scattering (LALLS) or multi-angle laser light scattering (MALLS) of the starch-molecular weight modifier composites of the present disclosure may or may not represent actual average molecular weight increases of the starch itself, and/or may or may not represent an average molecular weight of a starch-molecular weight modifier composite (intercalated and/or exfoliated composite(s)), where the average molecular weight of the starch is essentially unchanged from prior to formation of the starch-molecular weight modifier composite.

[0048] In one aspect, alone or in combination with any one of the previous aspects, the method further comprises crosslinking the starch-molecular weight modifier composition during or after extrusion. In one aspect, alone or in combination with any one of the previous aspects, crosslinking is selected from the group consisting of EB crosslinking, UV crosslinking, thermal and/or chemical crosslinking and combinations thereof.

[0049] In one aspect, alone or in combination with any one of the previous aspects, the starch present in the film is a thermoplastic starch. In one aspect, alone or in combination with any one of the previous aspects, the starch present in the film is an alkyl etherized starch, carboxyalkyl etherized starch, hydroxyalkyl etherized starch having a hydroxyalkyl group having 2 to 6 carbon atoms, and synthetic starches.

[0050] In one aspect, alone or in combination with any one of the previous aspects, the starch is derived from cassava, corn, potato, sweet potato, sago, tapioca, sorghum, bean, bracken, lotus, Trapa japonica, wheat, rice, oat, arrowroot, dent, or pea. In one aspect, alone or in combination with any one of the previous aspects, the starch is glutinous rice, waxy potato starch, and waxy corn.

[0051] In one aspect, alone or in combination with any one of the previous aspects, the starch comprises a modified starch with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100. In one aspect, alone or in combination with any one of the previous aspects, the starch is a blend of modified starches with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100. In one aspect, alone or in combination with any one of the previous aspects, the starch comprises a combination of a first starch having an amylose to amylopectin weight ratio between 40:60 to 0:100 and a second starch having an amylose to amylopectin weight ratio between 40:60 to 0:100, where at least one of the first starch and the second starch, independently, is unmodified, modified, synthetic, or crosslinked.

[0052] In another example, a process for producing a retrogradation-resistant starch film composition is provided, the process comprising: continuously or semi-continuously metering into a low shear extrusion equipment a starch film composition comprising a starch, modified starch, thermoplastic starch, or combination, a state of water, and a molecular weight modifier; continuously mixing the composition in a compounding section of the low shear extrusion equipment; and continuously discharging a retrogradationresistant starch film from the extruder.

[0053] In one aspect, , the compounding sections comprises a plurality of roller barrel sections. In one aspect, alone or in combination with any one of the previous aspects, each roller barrel section comprises a plurality of mixing spindles.

[0054] In one aspect, alone or in combination with any one of the previous aspects, the process further comprising adding the state of water to the composition in the compounding section. In one aspect, alone or in combination with any one of the previous aspects, the state of water is liquid, steam, or a combination of liquid and steam. In examples, the starch is preconditioned, e.g., introducing of heat and water.

[0055] In one aspect, alone or in combination with any one of the previous aspects, the process further comprising adding additional materials. In one aspect, alone or in combination with any one of the previous aspects, the additional materials comprise solid, liquid or gaseous materials. In one aspect, alone or in combination with any one of the previous aspects, the solid, liquid or gaseous materials are selected from one or more of polyhydric alcohols, waxes, hydrocarbon oil, mineral oil, polyethylene glycol, propylene glycol, polyethylene oxide, polypropylene oxide, glycerine, glycerol, mannitol, pentaerythritol, trimethylpropane, starch, chitosan, erythritol, polyethylene amines, ethanolamines, and ionic polymers, thermoplastic elastomers, resins, extenders, activators, anti-degradants, biocides, humectants, blowing agents, crosslinkers and mixtures thereof. [0056] In one aspect, alone or in combination with any one of the previous aspects, the compounding section further comprises a dosing unit and the solid materials are added to the compounding section via the dosing unit.

[0057] In another example, a sustainable fluid-fillable air cushion is provided, the cushion comprising a first layer comprising a repulpable material, a second layer comprising a repulpable material adjacently affixed to the first layer, and an air fillable portion integral with the second layer.

[0058] In another example, a sustainable fluid-fillable air cushion is provided, the cushion comprising a first layer comprising a repulpable material, a second layer comprising a water-soluble material adjacently affixed to the first layer, and an air fillable portion integral with the second layer.

[0059] In another example, a sustainable fluid-fillable air cushion is provided, the cushion comprising a first layer comprising a water-soluble material, a second layer comprising a water-soluble material adjacently affixed to the first layer, and an air fillable portion integral with the second layer.

[0060] In another example, a sustainable fluid-fillable air cushion is provided, the cushion comprising a first layer comprising a water-soluble material, a second layer comprising a repulpable material adjacently affixed to the first layer, and an air fillable portion integral with the second layer.

[0061] In one aspect, the repulpable material of the sustainable fluid-fillable air cushion is the retrogradation-resistant starch film as presently disclosed. In another aspect, alone or in combination with any one of the previous aspects, the repulpable material of the sustainable fluid-fillable air cushion is the retrogradation-resistant starch film as presently disclosed laminated with a PVOH film. Such a sustainable fluid-fillable air cushion is "paper- free." [0062] In one aspect, the repulpable material of the sustainable fluid-fillable air cushion is cellulosic sheet. In another aspect, alone or in combination with any one of the previous aspects, the repulpable material of the sustainable fluid-fillable air cushion is kraft paper sheet.

[0063] In another aspect, alone or in combination with any one of the previous aspects, the water-soluble material layer of the sustainable fluid-fillable air cushion comprises polyvinyl alcohol (PVOH). In another aspect, alone or in combination with any one of the previous aspects, the PVOH is plasticized. In another aspect, alone or in combination with any one of the previous aspects, the PVOH is plasticized with one or more of polyhydric alcohols, waxes, hydrocarbon oil, mineral oil, polyethylene glycol, propylene glycol, polyethylene oxide, polypropylene oxide, glycerine, glycerol, mannitol, pentaerythritol, trimethylpropane, starch, chitosan, erythritol, polyethylene amines, ethanolamines, and ionic polymers.

[0064] In another aspect, alone or in combination with any one of the previous aspects, the PVOH is a copolymer or blend. In another aspect, alone or in combination with any one of the previous aspects, the copolymer comprises at least one anionic monomer unit. In another aspect, alone or in combination with any one of the previous aspects, the PVOH is a blend of a first PVOH copolymer comprising a first anionic monomer unit, and a second PVOH copolymer comprising a second anionic monomer unit wherein the first anionic monomer unit and the second anionic monomer unit of the blend is the same or different.

[0065] In another example, a mailer comprising the sustainable air cushion as defined in any one of the previous aspects is provided. In another example, a repulpable mailer comprising the sustainable air cushion as defined in any one of the previous aspects is provided.

[0066] In yet another example, a method of forming a sustainable air cushion or mailer is provided, the method comprising contacting a bottom major surface of a repulpable material with a top major surface of a water-soluble material, and creating an fluid-fillable cushion between the repulpable material and the water-soluble material. In yet another example, a method of forming a sustainable air cushion or mailer is provided, the method comprising contacting a bottom major surface of a retrogradation-resistant starch film as described herein with a top major surface of a water-soluble material, e.g., PVOH, and creating an fluid-fillable cushion between the retrogradation-resistant starch film and the PVOH film.

[0067] In one aspect, the repulpable material of the sustainable fluid-fillable air cushion is a paper sheet. In another aspect, alone or in combination with any one of the previous aspects, the paper sheet is kraft paper.

[0068] In another aspect, alone or in combination with any one of the previous aspects, the water-soluble material of the sustainable fluid-fillable air cushion comprises polyvinyl alcohol (PVOH). In another aspect, alone or in combination with any one of the previous aspects, the PVOH is plasticized. In another aspect, alone or in combination with any one of the previous aspects, the PVOH is plasticized with one or more of polyhydric alcohols, waxes, hydrocarbon oil, mineral oil, polyethylene glycol, propylene glycol, polyethylene oxide, polypropylene oxide, glycerine, mannitol, pentaerythritol, trimethylpropane, starch, chitosan, erythritol, polyethylene amines, ethanolamines, and ionic polymers.

[0069] In another aspect, alone or in combination with any one of the previous aspects, the PVOH is a copolymer or blend. In another aspect, alone or in combination with any one of the previous aspects, the copolymer comprises at least one anionic monomer unit. In another aspect, alone or in combination with any one of the previous aspects, the PVOH is a blend of a first PVOH copolymer comprising a first anionic monomer unit, and a second PVOH copolymer comprising a second anionic monomer unit wherein the first anionic monomer unit and the second anionic monomer unit of the blend is the same or different.

[0070] In another aspect, alone or in combination with any one of the previous aspects, the repulpable material and the water soluble material are contacted by solvent coating, extrusion lamination, calendaring, or extrusion coating.

BRIEF DESCRIPTION OF THE DRAWINGS

[0071] In order to understand and to see how the present disclosure may be carried out in practice, examples will now be described, by way of non-limiting examples only, with reference to the accompanying drawings, in which:

[0072] FIG. 1A is a perspective view of a roll of tape for one example of the disclosure;

[0073] FIG. IB is an enlarged cross-sectional view of the tape of FIG. 1A, illustrating the layers thereof along line 2-2 of FIG. 1A;

[0074] FIG. 2A is a perspective view of a roll of tape for one example of the disclosure; [0075] FIG. 2B is an enlarged cross-sectional view of the tape of FIG. 2A, illustrating the layers thereof along line 3-3 of FIG. 2A;

[0076] FIG. 3A is a perspective view of a roll of tape for one example of the disclosure.

[0077] FIG. 3B is an enlarged cross-sectional view of the tape of FIG. 3A, illustrating the layers thereof along line 4-4 of FIG. 3A;

[0078] FIG. 4 depicts a an air pillow aspect of the present disclosure comprising retrogradation-resistant starch comprising films of the present disclosure.

[0079] FIG. 5 depicts a retrogradation-resistant starch comprising film/sheet lamination process aspect of the present disclosure.

[0080] FIG. 6 depicts an extrusion coating aspect of the present disclosure.

[0081] FIG. 7 depicts a calender extrusion process aspect of the present disclosure

[0082] FIG. 8 depicts an exemplary mailer aspect of retrogradation-resistant starch comprising film of the present disclosure.

[0083] FIG. 9 depicts an exemplary process flow for providing the retrogradationresistant starch comprising films or pellets of the present disclosure.

DETAILED DESCRIPTION

[0084] As used herein, the term "fluid" refers generally to liquid, gases, and combinations thereof unless specifically stated otherwise. In examples, fluid refers to air at or above atmospheric or ambient pressure.

[0085] As used herein, the term "repulpable" is inclusive of the 2013 Fibre Box Association Voluntary Standard for Repulping and Recycling Corrugated Fiberboard Treated to Improve Its Performance in the Presence of Water and Water Vapor ("FBA method").

[0086] As used herein "repulpable materials" are inclusive of starch, polyvinyl alcohol or polyvinyl alcohol copolymer and salts thereof, polyethyleneimines, polyvinyl pyrrolidones, polyalkylene oxides, polyhydroxyalkanoates, polyacrylamides, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polyamides, poly(meth)acrylic acid, poly(meth)acrylates and salts thereof, gelatines, methylcelluloses, carboxymethylcelluloses and salts thereof, ethylcelluloses, hydroxyethyl celluloses, hydroxypropyl methylcelluloses, dextrins, maltodextrins, guar gum, gum Acacia, gum Arabic, xanthan gum, carrageenan, algin, Locust Bean, gellan copolymers thereof, blends thereof, carbohydrates, proteins, lipids, triglycerides, glycerol, and phospholipids, alone or in combination with any of the above.

[0087] As used herein, "water-soluble" as used in the context of a material, filament, yarn or ribbon is inclusive of substantial or complete dissolution of the material, film, filament, yarn or ribbon in a repulping environment or process. In one aspect, as used herein, "water-soluble" as used in the context of a material, film, filament, yarn or ribbon is inclusive of substantial or complete dissolution of the material, filament, yarn or ribbon in an aqueous environment at a temperature of about 40-100 °C. In another aspect, as used herein, "water-soluble" as used in the context of a material, film, filament, yarn or ribbon is inclusive of substantial or complete dissolution of the material, filament, yarn or ribbon in an aqueous environment and a temperature of about 40-100 °C.

[0088] As used herein, "derivatives" as used in the context of a material, is inclusive of a physical or chemical modification to the material, such as grafting, co-polymerization, blending, and/or exposing to high-energy radiation sources (i.e., crosslinking or chain scissoring).

[0089] In examples, the presently disclosed air cushion or mailer provides an alternative to polyolefin air cushion or mailer by using a starch film and/or a starch film/PVOH laminate. In yet another example, the presently disclosed air cushion or mailer provides an alternative to polyolefin air cushion or mailer by using film comprising starch in combination with polyvinyl alcohol. In examples the starch film and/or a starch film/PVOH is machine direction-oriented. Thus, the disclosed air cushion or mailer are an improvement over previous packaging cushions using a non-water soluble plastic film as an air cushion or mailer and can exclude the use of paper.

[0090] The present disclosure provides for retrogradation-resistant starch films and the compounding and/or extrusion of such starch containing films.

[0091] In one aspect, the present disclosure provides for the compounding and/or extrusion of starch with amylose or essentially without amylose. In one aspect, the present disclosure provides for compounding and/or extrusion of retrogradation-resistant starch that is less than 40 weight percent amylose, less than 30 weight percent amylose, less than 20 weight percent amylose, less than 10 weight percent amylose, less than 9 weight percent amylose, less than 8 weight percent amylose, less than 7 weight percent amylose, less than 6 weight percent amylose, less than 5 weight percent amylose, less than 4 weight percent amylose, less than 3 weight percent amylose, less than 2 weight percent amylose, less than 1 weight percent amylose (essentially all amylopectin).

[0092] In one aspect, the present disclosure provides for compounding and/or extrusion of high amylopectin content, alone or with other materials, processed in such a way to substantially preserve molecular weight and branching of the amylopectin. In one aspect, the present disclosure provides for compounding and/or extrusion of high amylopectin content, alone or with other materials, processed in such a way to substantially increase molecular weight (50%, 100%, 200% or more) and substantially preserve branching of the amylopectin. Compounding/extrusion applications of such starch materials can be applied to packaging applications, for example, providing tenacious films capable of reinforcing water activated tapes (WATs) tape as well as providing films for use as stretch film, shrink film, duct tape backing, polyolefin tapes, air pillows/cushions, bubble wrap for use on its own or in mailers. Additionally, compounding/extrusion applications of such starch materials and the preparation of film or sheet are amenable to sachet's, such as those currently used for condiments, health/hygiene, condiments, and detergent pods. In addition, compounding/extrusion applications of such starch materials are employable to address water sensitivity requirements for certain applications by balancing amylose/amylopectin ratios and/or control of molecular weight changes and/or branching of the starch, and/or complexing of the starch with one or more components during compounding and/or extrusion.

[0093] Such retrogradation-resistant starch film/sheet as disclosed herein are useful in providing substrates for receiving CVD/PVD SiOx and/or AIOx coatings with improved air/water barrier properties Such retrogradation-resistant starch materials as disclosed herein are configured to receive paint or varnishes. Such retrogradation-resistant starch film/sheet as disclosed herein can comprise plasticizers, fillers, other polymers, biocides, humectants, UV stabilizers, and the like.

[0094] In examples, compositions of retrogradation-resistant starch comprising compositions using low shear extrusion equipment and products made therefrom are provided. Such products provide for sustainable or recyclable, and/or repulpable products

Y1 that can be used alone or in combination with packaging that is also sustainable or recyclable, circular, compostable, agnostically disposabe, and/or repulpable.

[0095] As used herein, the phrase "water activated adhesive" is inclusive of adhesives that are generally non-adhesive dry and become adhesive upon exposure to an aqueous medium where the aqueous medium comprises water and optionally other solvents such as alcohols.

[0096] As used herein, the phrase "state of water" is inclusive of water in a solid, liquid, or gaseous and/or steam state. The state of water can comprise additional solvents such as alcohols and other unintentional impurities.

[0097] As used herein, "starch" and "starch comprising" is inclusive of any synthetic or botanic starch, or blends thereof, and combinations, blends, or grafts with one or more polymers. As used herein, "botanical starch" is starch isolated, derived, and or purified from any botanical source by any means. In examples, the botanical starch is derived or obtained from, but not limited to, cassava, corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes. Other sources of botanical and non-botanical starch can be employed.

[0098] As used herein, synthetic starch is inclusive of "modified botanical starch" e.g., any botanical starch that is modified chemically, genetically, enzymatically, mechanically and/or thermally. As used herein, synthetic starch is also inclusive of non-botanical starch, e.g., starch prepared from carbon dioxide.

[0099] As used herein "modified starch" is inclusive of starch that is epoxidized, alkylated, carboxylated, carboxymethylated, alkylacetylated, alkaline-modified, bleached, oxidized, enzyme-treated, phosphorylated, phosphated, hydroxy alkylated, borax-treated, urea treated, urea-formaldehyde treated, resorcinol-formaldehyde treated, thermally treated, dry heated, acid or enzyme-thinned, or dextrinized.

[0100] As used herein "retrogradation-resistant starch film" is inclusive of films comprising starch, where the starch does not undergo retrogradation for at least 6 months, at least 9 months, at least 1 year, or for more than 1 year. Retrogradation includes a freezing water content of less than 1% by mass, of less than 0.1% by mass, of less than 0.001% by mass, undetectable freezing water content, embrittlement, haziness or clouding, change in solubility, and any other negative physical properties that would diminish the performance of a starch film for its intended purpose. In examples, a starch film prepared by the methods disclosed herein represents a retrogradation-resistant starch film.

[0101] Mixing and/or extrusion equipment includes, by way of non-limiting examples, planetary roller extruders (PRE), planetary roller mixers, twin-screw extruders configured with counter- or co-rotating, intermeshing or non-intermeshing screws, static mixing devices, and the like. PRE's have typically been used in processing of thermoplastics such as PVC, for example, where they were used primarily to supply downstream units such as, for example, cast or blown film devices, calenders or roll mills. Planetary roller extruders can be used to process heat-sensitive compounds with a minimum of degradation, for example, by facilitating thin layers of compound exposed to large surface areas, thereby resulting in effective heat exchange, mixing and temperature control. Planetary roller extruders are available in various designs and sizes. The diameters of the roll cylinders, depending on the desired throughput, are typically between 30mm to 1000 mm, or 70 mm and 500 mm.

[0102] Planetary roller extruders generally have a filling section and a compounding section. The filling section typically includes a conveying screw to which certain raw materials are fed continuously. The conveying screw then passes the material to the compounding section. The compounding section includes a driven main spindle and a number of planetary spindles which rotate around the main spindle within a roll cylinder with internal helical gearing. The rotary speed of the main spindle and hence the rotational speed of the planetary spindles can be varied and is one parameter to be controlled during the compounding process. The materials are circulated between the main and planetary spindles, or between the planetary spindles and the helical gearing of the roll section, so that under the materials are dispersed to form a homogeneous composition.

[0103] The number of planetary spindles (e.g., back-cut, swirled, or ground spindles) rotating in each roll cylinder can be varied and thus adapted to the requirements of the process. The number of spindles influences the free volume within the planetary roller extruder, the residence time of the material in the process, and also determines the surface area for heat and material exchange. By way of the dispersive energy introduced, the number of planetary spindles has an influence on the result of compounding. Given a constant diameter of roll cylinder, a larger number of spindles permit better homogenization and dispersion or, respectively, a greater product throughput. [0104] The maximum number of planetary spindles installable between the main spindle and the roll cylinder depends on the diameter of the roll cylinder and on the diameter of the planetary spindles used. When using relatively large barrel diameters, as required for obtaining production-scale throughputs, and/or relatively small diameters for the planetary spindles, the roll cylinders can be equipped with a relatively large number of planetary spindles. For example, with a barrel diameter of D=70 mm, typically up to seven planetary spindles are used, whereas with a barrel diameter of D=200 mm ten, and a barrel diameter of D=400 mm 24 for example, planetary spindles can be used. However, these examples are in no way limiting to those skilled in the art. For example, if the diameter of the main spindle is smaller relative to a larger main spindle, the number of planetary spindles can be increased. Likewise, if the diameter of the main spindle is greater relative to a larger main spindle, the number of planetary spindles can be decreased.

[0105] Turning now to the drawings, and referring initially to FIG. 1A, an exemplary process for providing a roll of tape, e.g., a WAT is shown. Likewise, and paper-based backing construct can be substituted with the process and materials herein disclosed. Thus, as shown in FIG. 1A, roll 200 of tape 130 wound onto a core 118, the role of tape having, optionally, a paper backing 124 and a retrogradation-resistant starch comprising film 123. Referring to FIGS. 1A and IB for explanation, from top to bottom relative to the page, the tape 130 includes a paper backing 124. The paper backing 124 (also referred to as a substrate) has a first major (top) surface 132, a second major (bottom) surface 134, and a first side and a second side. As shown, applied to the bottom surface 134 of the backing 124 is the a retrogradation-resistant starch comprising film 123. Retrogradation-resistant starch comprising film 123 is configured to function as an support for an adhesive, for example a water activated adhesive. For example, the retrogradation-resistant starch comprising film 123 carrying adhesive can be activated using an aqueous medium such as water or water and alcohol prior to use. In examples, the retrogradation-resistant starch comprising film 123 is a film, web, scrim, or layer.

[0106] With reference to FIG. 2A, a roll 300 of tape 130 wound onto a core 118 is shown, the role of tape having optionally a paper backing 124, a retrogradation-resistant starch comprising film 123, and an adhesive 114. Referring to FIGS. 2A and 2B for explanation, from top to bottom relative to the page, the tape 130 includes optional paper backing 124. The paper backing 124 (also referred to as a substrate) has a first major (top) surface 132, a second major (bottom) surface 134, and a first side and a second side. As shown, a retrogradation-resistant starch comprising film 123 can be positioned adjacent to the optional paper backing 124, and an adhesive 114 is applied to the opposing surface of the retrogradation-resistant starch comprising film 123. In examples, the adhesive 114 is water activated adhesive. In another example, the adhesive 114 is a pressure sensitive adhesive. In examples, the paper backing 124 is not used for providing tape 130.

[0107] With reference to FIG. 3A, a roll 400 of tape 130 wound onto a core 118 the role of tape having an optional paper backing 124, a retrogradation-resistant starch comprising film 123, a paper layer 112 and an adhesive 114. Referring to FIGS. 3A and 3B for explanation, from top to bottom relative to the page, the tape 130 includes optional paper backing 124. The paper backing 124 (also referred to as a substrate) has a first major (top) surface 132, a second major (bottom) surface 134, and a first side and a second side. As shown, a retrogradation-resistant starch comprising film 123 can be positioned adjacent to the paper backing 124. As shown in FIGs. 3A, 3B, additional paper layer 112 is positioned adjacent an opposing surface of the retrogradation-resistant starch comprising film 123. Adhesive 114 is applied to an opposing surface of the paper layer 112. In examples, the adhesive 114 is water activated adhesive. In another example, the adhesive 114 is a pressure sensitive adhesive.

[0108] In examples, the backing 124, if used, and retrogradation-resistant starch comprising film 123 are extrusion laminated together. In examples, the backing 124 and retrogradation-resistant starch comprising film 123 are extrusion laminated without an additional material, e.g., one surface of the retrogradation-resistant starch comprising film 123 is activated, e.g., with a state of water and laminated directly to the paper backing 124. In another example, the backing 124 and retrogradation-resistant starch comprising film 123 are extrusion laminated together with a softened or molten layer therebetween that laminates the layers together, which once set, solidifies. The softened or molten layer can be extruded between the backing 124 and retrogradation-resistant starch comprising film 123 or coextruded with the retrogradation-resistant starch comprising film 123.

[0109] In examples, the backing 124 and retrogradation-resistant starch comprising film 123 are adhesive laminated. In examples, the backing 124 and retrogradation-resistant starch comprising film 123 are adhesive laminated without an adhesive, e.g., one surface of the retrogradation-resistant starch comprising film 123 is activated, e.g., with a state of water and adhered directly to the paper backing 124. In another example, the backing 124 and retrogradation-resistant starch comprising film 123 are adhesive laminated together with a layer or discontinuous pattern of adhesive therebetween that adheres the layers together. The adhesive can be extruded between the backing 124 and retrogradationresistant starch comprising film 123 or coextruded with the retrogradation-resistant starch comprising film 123.

[0110] With reference to roll 300, In examples, the adhesive 114 and retrogradationresistant starch comprising film 123 are extrusion laminated. In examples, the adhesive 114 and retrogradation-resistant starch comprising film 123 are extrusion laminated without an additional material, e.g., one surface of the retrogradation-resistant starch comprising film 123 is activated, e.g., with a state of water and laminated directly to the adhesive 114. In another example, the adhesive 114 and retrogradation-resistant starch comprising film 123 are extrusion laminated together with a softened or molten layer therebetween that laminates the layers together, which once set, solidifies. The softened or molten layer can be extruded between the adhesive 114 and retrogradation-resistant starch comprising film 123 or coextruded with the retrogradation-resistant starch comprising film 123.

[0111] In examples, the adhesive 114 and retrogradation-resistant starch comprising film 123 are adhesive laminated so as to provide a paperless tape. In examples, the adhesive 114 and retrogradation-resistant starch comprising film 123 are adhesive laminated without an adhesive, e.g., one surface of the retrogradation-resistant starch comprising film 123 is activated, e.g., with a state of water and adhered directly to the adhesive 114. In another example, the adhesive 114 and retrogradation-resistant starch comprising film 123 are adhesive laminated together with a layer or discontinuous pattern of adhesive therebetween that adheres the layers together. The adhesive can be extruded between the adhesive 114 and retrogradation-resistant starch comprising film 123 or coextruded with the retrogradation-resistant starch comprising film 123.

[0112] With reference to roll 400, In examples, optional backing 124 and retrogradationresistant starch comprising film 123 are extrusion laminated. In examples, the backing 124 and retrogradation-resistant starch comprising film 123 are extrusion laminated without an additional material, e.g., one surface of the retrogradation-resistant starch comprising film 123 is activated, e.g., with a state of water and laminated directly to the paper backing 124. As shown, roll 400 further comprises a paper layer 112 adjacent the opposing side of the retrogradation-resistant starch comprising film 123. In examples, the paper layer 112 and retrogradation-resistant starch comprising film 123 are extrusion laminated. In examples, the paper layer 112 and retrogradation-resistant starch comprising film 123 are extrusion laminated without an additional material, e.g., one surface of the retrogradation-resistant starch comprising film 123 is activated, e.g., with a state of water and laminated directly to the paper layer 112.

[0113] In examples, the optional paper backing 124, retrogradation-resistant starch comprising film 123, and paper layer 112 are extrusion laminated together. In examples, the paper backing 124, retrogradation-resistant starch comprising film 123, and paper layer 112 are extrusion laminated together without an additional material, e.g., both surfaces of the retrogradation-resistant starch comprising film 123 are activated, e.g., with a state of water and laminated directly to the paper backing 124 and paper layer 112. Adhesive 114 is positioned adjacent the opposing surface of paper layer 112. In examples, adhesive 114 is extrusion laminated to paper layer 112. In another example, adhesive 114 is adhesive laminated to paper layer 112.

[0114] In examples, the paper backing 124, retrogradation-resistant starch comprising film 123, and paper layer 112 are adhesive laminated. In examples, the paper backing 124, retrogradation-resistant starch comprising film 123, and paper layer 112 are adhesive laminated without an adhesive, e.g., both surfaces of the retrogradation-resistant starch comprising film 123 are activated, e.g., with a state of water and adhered directly to the paper backing 124 and paper layer 112. In another example, the paper backing 124, retrogradation-resistant starch comprising film 123, and paper layer 112 are adhesive laminated together with a layer or discontinuous pattern of adhesive therebetween that adheres one or more or all of the layers together. The adhesive can be extruded between one or more of the paper backing 124, retrogradation-resistant starch comprising film 123, and paper layer 112 or coextruded with the retrogradation-resistant starch comprising film

123. [0115] In examples, the adhesive 114 of roll 400 is extrusion or adhesive laminated directly to the paper layer 112. In another example, the adhesive 114 and paper layer 112 are adhesive laminated together with a layer or discontinuous pattern of adhesive therebetween that adheres the layers together. The adhesive can be extruded between the adhesive 114 and retrogradation-resistant starch comprising film 123 or coextruded with the retrogradation-resistant starch comprising film 123.

[0116] The aforementioned processing steps for rolls 200, 300, or 400 can be carried out continuously, semi-continuously, or in batches. Optionally, applied to the top surface of the paper backing 124 is a release layer. In examples, the roll 200, 300, 400 is without a release layer.

[0117] Examples of the starch include starches derived from cassava, corn, potato, sweet potato, sago, tapioca, sorghum, bean, bracken, lotus, Trapa japonica, wheat, rice, oat, arrowroot, pea, and the like. In examples, starch derived or modified from corn or cassava is used. In another example, starch derived or modified from high amylose corn is used.

[0118] The starch may be a single substance, or may be a mixture of two or more starches, two or more modified starches, a modified starches and a non-modified starch, a cross-linked starch, a cross-linked starch combined with one or more modified starches or uncrosslinked starch. In examples, the reinforcement starch is derived from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent and/or potatoes. In examples, the starch is derived from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent and/or potatoes. In examples, the starch is a blend of an unmodified starch and a modified starch, selected from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes. In examples, the starch is a blend of two or more starches, independently selected from an unmodified starch, a modified starch, or crosslinked starch of corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes. In examples, the starch is a blend of two or more starches, independently selected from an unmodified starch, a modified starch, or crosslinked starch of corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes and one or more a synthetic starches.

[0119] In examples, the starch or modified starch as a content of amylopectin of 50% by mass or more, 55% by mass or more, 60% by mass or more, 70 % by mass or more, 80 by mass or more, 90 % by mass or more. In examples, the starch or modified starch as a content of amylose of 50% by mass or more, 55% by mass or more, 60% by mass or more, 70 % by mass or more, 80 % by mass or more, 90 % by mass or more.

[0120] Independently, with regard to either the starch, modified starch or synthetic starch an amylose to amylopectin weight ratio between 40:60 to 0:100 can be employed. A blend of starches with a combined amylopectin weight ratio between 40:60 to 0:100 can be employed. A modified starch having an amylose to amylopectin weight ratio between 40:60 to 0:100, or a blend of modified starches with a combined amylose to amylopectin weight ratio between 40:60 to 0:100 can be employed. A combination of a first starch having an amylose to amylopectin weight ratio between 40:60 to 0:100 and a second starch having an amylose to amylopectin weight ratio between 40:60 to 0:100, where at least one of the first starch and the second starch, independently, is unmodified, modified, synthetic, or crosslinked can be employed.

[0121] Examples of modified starch include alkyl etherized starches such as methyl etherized starch, carboxyalkyl etherized starches such as carboxymethyl etherized starch, and hydroxyalkyl etherized starches such as etherized starch having a hydroxyalkyl group having 2 to 6 carbon atoms, and the like. Alternatively, allyl etherized starches and the like can also be used as a modified starch.

[0122] Additional examples of modified starches include esterified starches having a structural unit derived from carboxylic acid, such as esterified starch having a structural unit derived from acetic acid; esterified starches having a structural unit derived from dicarboxylic anhydride, such as esterified starch having a structural unit derived from maleic anhydride, esterified starch having a structural unit derived from phthalic anhydride, and esterified starch having a structural unit derived from octenylsuccinic anhydride; esterified starches having a structural unit derived from oxo acid, such as nitric acid esterified starch, phosphoric acid esterified starch, and urea-phosphoric acid esterified starch. Other examples thereof include xanthogenic acid esterified starch, acetoacetic acid esterified starch, and the like. Alkoxyl silane/siloxane TEOS, etc

[0123] Examples of crosslinked starch include formaldehyde-crosslinked starch, epichlorhydrin-crosslinked starch, phosphoric acid-crosslinked starch, acrolein-crosslinked starch, sodium tetraborate crosslinked starch, and the like. [0124] In examples, the retrogradation-resistant starch film, web, scrim, or layer as disclosed herein, in a dry state, comprises a water content of about 10 to 15% by mass of the film, as determined by ASTM E 203 or ISO 760. In examples, the retrogradationresistant starch film, web, scrim, or layer, in a dry state, comprises a freezing water content of less than 1% by mass, of less than 0.1% by mass, or of less than 0.001% by mass, by mass as determined by Dynamic Scanning Calorimetry (DSC). In examples, the retrogradationresistant starch film, web, scrim, or layer, in a dry state, comprises an undetectable freezing water content as determined by Dynamic Scanning Calorimetry (DSC). In examples, the retrogradation-resistant starch films disclosed herein with a freezing water content of less than 1% by mass, of less than 0.1% by mass, of less than 0.001% by mass or undetectable freezing water content do not undergo retrogradation for at least 6 months, at least 9 months, at least 1 year or more than 1 year.

[0125] In examples, the adhesive 114 is any conventional adhesive or hereinafter developed adhesive suitable for box sealing or carton sealing tapes (also referred to as packaging tapes). In examples, the adhesive 114 can be a water activated adhesive. In examples, the adhesive 114 can be a water activated adhesive used together with an amorphous polyolefin adhesive, a natural rubber adhesive, and the like. In examples, the adhesive 114 can be mixed or blended with an amorphous polyolefin adhesive, a natural rubber adhesive, a poly(meth)acrylate adhesive and the like. In examples, the adhesive 114 can be layered on a layer, or between layers of an amorphous polyolefin adhesive, a natural rubber adhesive, and the like, e.g., a layer/film or pattern of pressure sensitive adhesive and a layer/film or pattern of water-activated adhesive, etc.

[0126] In examples, the adhesive 114 is a starch comprising adhesive from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes. In examples, the adhesive 114 is a crosslinked starch comprising adhesive from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent and/or potatoes. In examples, the adhesive 114 is a blend of two or more, independently selected unmodified starch, modified starch, and crosslinked starch comprising adhesive, independently selected from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes. In examples, the adhesive 114 is a blend of two or more, independently selected unmodified starch, modified starch, and crosslinked starch comprising adhesive, independently selected from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, dent, pea, and/or potatoes and one or more synthetic starches and non-starch comprising adhesive. The adhesive 114 can be the same or different composition as that of the retrogradation-resistant starch comprising film 123.

[0127] In another embodiment, the adhesive 114 may be a polyvinyl alcohol, polyvinyl alcohol copolymer, polyvinyl alcohol blend remoistenable adhesive. In another embodiment, the adhesive 114 may be a blend of one or more polyvinyl alcohol, polyvinyl alcohol copolymer, polyvinyl alcohol blend remoistenable adhesives and any of the aforementioned starch adhesives.

[0128] With reference to FIGs. 4-7, In examples, the retrogradation-resistant starch comprising film 123 is contiguous to either a paper backing 124 or another retrogradationresistant starch comprising film and includes coextruding the retrogradation-resistant starch comprising film 123 directly onto the paper backing or the another retrogradation-resistant starch comprising film so as to form an air pillow precursor or an air pillow direction, e.g., "on-demand." The method may also include reducing the temperature of the retrogradation-resistant starch comprising film 123 after its extruding and before contact with the paper backing 124 or another retrogradation-resistant starch comprising film. Forming air pillows using methods and equipment know in the art is envisaged using the retrogradation-resistant starch comprising film 123.

[0129] In examples, the starch composition used to prepare the retrogradation-resistant starch comprising film 123 can comprise additives such as fillers, processing stabilizers, weather resistance stabilizers, coloring agents, ultraviolet absorbing agents, light stabilizers, antioxidants, antistatic agents, flame-retardants, plasticizers, other impact modifiers, lubricants, perfumes, antifoaming agents, deodorants, bulking agents, releasing agents, mold releasing agents, reinforcing agents, crosslinking agents, fungicides, biocides, humectants, antiseptics, and crystallization rate retardants as necessary, in such a range that the effect of the present disclosure is not hindered.

[0130] The present retrogradation-resistant starch comprising film 123 and its precursor composition of the present disclosure can be produced by a production method comprising continuously, semi-continuously, or batch mixing an amount of starch and an amount of molecular weight modifier while heating in a mixer and obtaining a extrudate; continuous extruding the extrudate; cooling the extrudate to form a repulpable film or pellet.

[0131] Another embodiment of the disclosure involves coating the retrogradationresistant starch comprising film 123 on a paper backing or PVOH film using any of a variety of coating techniques including, but not limited to, slot-die coating, roll-over-roll coating, reverse roll and knife-over-roll coating. In accordance with certain embodiments of the present disclosure, the adhesive composition is applied to the retrogradation-resistant starch film and/or any intervening paper/PVOH material using a slot-die applicator unit. Particularly useful methods for applying the adhesive composition to the web-form material include slot-die coating using a rotating lip die or a fixed lip contact die. One particular slot die unit that can be used is a rotating lip die having a spindle that trails the die lip.

[0132] In accordance with another aspect of the present disclosure, the retrogradationresistant starch comprising film may be crosslinked. More specifically the retrogradationresistant starch comprising film may be crosslinked thermally, chemically, e.g., with azides, sodium tetraborate, epoxides, anhydrides, and/or with the aid of electron beams or UV rays by means of ionizing radiation, such as electron beams, for example, so that the resultant starch comprising film provides a shear-resistant and temperature-stable film, web, scrim or layer.

[0133] Simply stated, some advantages of certain embodiments of the new disclosure/method include; 1) purposeful, effective, and efficient compounding, e.g., with minimal shear of starch comprising compositions, 2) the introduction of various additional materials into the compounding section, 3) the introduction of solvent, hydrogen bonding polymer, molecular weight modifier, glycerol, or a state of water into the compounding section, and 4) the use of pelletizing, slot-die, annular die coating technology to achieve pellets, a web, a film, or a layer material.

[0134] The compounding of the presently disclosed starch or modified starch with hydrogen bonding polymer, molecular weight modifier, glycerol is accomplished as the starch is forced with the single-screw from the feeding section between the dosing ring and the main spindles into the compounding section, where it is intensively mixed and subsequently compounded. The degree of shear is minimized, for example, by the selection of transversal planetary spindles. Reduction of shear of the starch or modified starch translates into more efficient compounding of the starch with the hydrogen bonding polymer, molecular weight modifier, glycerol materials as well as other solid and liquid materials.

[0135] FIG. 4 illustrates a cross-section of air cushion 100 comprising at least starch film 123 of the present disclosure. In examples, laminates of starch film 123 with one or more water-soluble material layers, and/or repupable materials can be employed.

[0136] With regard to FIG. 5, an exemplary process 600 for providing a fluid-fillable or captured air cushion 200 of the present disclosure is shown. Top major surfaces of waterretrogradation-resistant starch comprising film 123 as a sheet or film, e.g., blown or cast sheet or film are combined at nip rolls 98 and featured roll 98. In examples, starch films 123 are activated via activating units 152 and/or nip rolls 98 and featured roll 98 are heated. In examples, starch films 123 are activated using an aqueous composition in activating unit 152. In examples, the aqueous composition is water and/or alcohol or a mixture of water and alcohol. Other activating agents can be employed. After being taken up by nip rolls 98 and featured roll 98, air pockets or cavities 175 between water soluble layers are introduced so as to form air cushion 200 or provide for a fluid-fillable preform. Finished fluid-fillable air cushion 200 or web can be taken up into a roll form for further processing (perforation) or can be continuously processed for inflation at the point of use or for point of use using captured air.

[0137] With reference to FIG. 6, another exemplary process 700 for providing the air cushion 200 of the present disclosure is provided. Repulpable layer 110, for example, kraft paper, or water soluble material layer 120, for example, PVOH are provided as a sheet are joined with retrogradation-resistant starch comprising film 123 provided from extruder 155 through a die 157 to a plurality of calender rolls 190 for providing a cast or calendered sheet of the retrogradation-resistant starch comprising film 123. In examples, top major surface of water-soluble material layer 120 or repulpable material layer 110 are activated prior to introduction to nip rolls 99. In examples, top major surface of retrogradation-resistant starch comprising film 123 is activated via activating units 152 using an aqueous composition, e.g., water and/or alcohol or mixture thereof. Other activating agents can be employed. In examples, top major surface of retrogradation-resistant starch comprising film 123 is heat sealed to water-soluble material layer 120 or repulpable layer 110. Top major surface of at least one water-soluble material layer 120 or repulpable layer 110 and top major surface of retrogradation-resistant starch comprising film 123 are affixed to each other by nip rolls 98/9, where pockets or cavities 175 are introduced so as to provide fluid- fillable or air captured cushion 200. Finished fluid-fillable or air captured cushion web 200 can be taken up into a roll form for further processing (perforation, flattened) or can be continuously processed to introduce air to air cushion, or sent to an end-user for inflation/air capture at point of use.

[0138] With reference to FIG. 7, an exemplary process 800 for providing air cushion 200 of the present disclosure is provided. Top major surface of at least one water-soluble material layer 120 or repulpable layer 110, provided as a sheet, is calender extrusion coated with starch film 123 extrudate from extruder 155 through a die 157. After top major surface of starch film 123 and top major surface of water-soluble material layer 120 or repulpable layer 110 are affixed to each other and fluid-fillable or air captured pockets created via roller 98, the fluid fillable or captured air cushion can be taken up into a roll form for further processing.

[0139] With reference to FIG. 8, a mailer 400 includes retrogradation-resistant starch comprising film 123 formed into a container for receiving goods through opening 119. In examples, retrogradation-resistant starch comprising film 123 is folded over and sealed along edges to provide mailer 400. Edges 116 are sealed about the folded structure except at opening 119. In one aspect, water-soluble material layers 120 are sealed together at edges 116, for example, using heat, solvent, or adhesive. In examples, a segment, or length of mailer 400 can comprise air pillows 200 as discussed above.

[0140] Folded air cushion 200 with sealed edges 116 can provide a suitable mailer 400 article for packaging. In examples, mailer 400 has three heat sealed edges. In examples, mailer 400 with sealed edges can have an extended portion 129, extending from opening 119 and opening edge 117, where extended portion is configured to fold over and seal the opening. In examples, an adhesive 130 is affixed to extended portion 129. In examples, adhesive is water activated. The adhesive 130 can be presented to the extended portion as a continuous or discontinuous film, applied dry or as a solution, such as by spray or electrostatic coating. The adhesive 130 may be any conventional developed adhesive suitable for box sealing or carton sealing (also referred to as packaging adhesive). In examples, the adhesive 130 can be a starch or starch derivative. In examples, the starch, starch derivative or thermoplastic starch is derived from corn, sorghum, wheat, sago, tapioca, legumes, barley, rice, and/or potatoes. In examples, the starch or starch derivative comprises maize, waxy maize, wheat, potato, tapioca, or mixtures thereof. In another example, adhesive 130 is a pressure sensitive adhesive (PSA) with or without a release liner (not shown). Paper layering or compounding of lignin or recycled paper particles can be used to present mailer 400 to meet consumer expectations.

[0141] As a result of the construction of the presently disclosed air cushion 100, 200, 300, 400 the cushion (or mailer) possesses the physical and structural attributes of a traditional air cushion or mailer carton sealing tape, for example, the ability to be printed, the ability to be perforated, filled, and sealed using conventional air cushion/dunnage equipment. Furthermore, the presently disclosed air cushion or mailer is at least 75%, at least 80%, at least 90%, or at least 95-99% (by weight) re-pulpable, as measured by the Fiber Box Association's (FBA) re-pulpability test method. Moreover, at least 75%, at least 80%, at least 90%, or at least 95-99% of the weight of the air cushion or mailer presently disclosed is environmentally disposable or countertop compostable.

[0142] In examples, retrogradation-resistant starch comprising film or pellets precursor compositions are provided as follows, with reference to FIG. 9 and process 900. Molecular weight modifier, selected from modified microfibrillated celluloses, nanofibril lated celluloses, modified nanofibrillated celluloses, sugar alcohols, dextrins, maltodextrins, synthetic and natural layered silicate clays, montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof of about 0.1 to about 10 wt.% was combined with water at about 25-50 wt.%, glycerol at about 40-60 wt.%, optionally urea at about 0.1 to about 10 wt.% and optionally a preservative at 0 to about 1 wt.%, e.g., sodium benzoate such that the total weight percent of the above components is 100 wt.%, (step 905) and intensely milled and mixed at or above room temperature to provide a free- flowing suspension or pre-mix (step 910). In examples, pre-mix provided at least partially exfoliated or at least partially intercalated material of about 10 nanometers to about 100 microns, about 50 nanometers to about 10 microns, about 100 nanometers to about 1 microns. [0143] The free-flowing suspension or pre-mix at about 30-50 wt.%, a starch (e.g., Amioca with <1.0% amylose content; Douglas Pearl with ~25% amylose content; or Pea starch with ~ 40% amylose content, or combinations thereof) at about 30-50 wt.%, and PVOH polymer (e.g., 90-99% hydrolyzed; 70,000-200,000 average molecular weight) at about 10-30 wt.% was combined in a mixing device at a temperature of less than 150 °C such that the total weight percent of the pre-mix, starch, and PVOH is about 100 wt.%, for a time sufficient to de-structure/paste the starch present (step 915), cooled and discharged or extruded at less than 100 °C as film or pellet (step 920).

[0144] Fil ms comprising the retrogradation-resistant starch, from pellets or as directly blown or cast films of 0.5 to 5 mil (about 13 to about 130 micron) thickness were prepared. The present methods provide for retrogradation-resistant starch comprising pellets and films from a variety of starches with varying amylose content that offers improvement in the manufacture of such articles. Films of retrogradation-resistant starch comprising film prepared by the method disclosed herein were translucent, soft and flexible, did not undergo retrogradation for at least 6 months, at least 9 months, at least 1 year, or for more than 1 year and comprised a freezing water content of less than 1% by mass, of less than 0.1% by mass, of less than 0.001% by mass, or undetectable freezing water content. The films exhibited no indication of embrittlement, haziness or clouding, or change in solubility over time and when submerged in water, swelled slightly with minimal tackiness and when subsequently dried, retained essentially all of the pre-submerged properties.

[0145] While certain embodiments of the present disclosure have been illustrated with reference to specific combinations of elements, various other combinations may also be provided without departing from the teachings of the present disclosure. Thus, the present disclosure should not be construed as being limited to the particular exemplary embodiments described herein and illustrated in the Figures, but may also encompass combinations of elements of the various illustrated embodiments and aspects thereof.

Claims

WE CLAIM:

1. A retrogradation-resistant starch comprising film or pellet, the film or pellet comprising: a starch; and an amount of molecular weight modifier.

2. The film or pellet of claim 1, wherein the starch of the retrogradation-resistant starch comprising film is derived from cassava, corn, potato, sweet potato, sago, tapioca, sorghum, bean, bracken, lotus, Trapa japonica, wheat, rice, oat, arrowroot, dent, or pea.

3. The film or pellet of any one of the previous claims, wherein the starch present in the retrogradation-resistant starch comprising film is glutinous rice, waxy potato starch, and waxy corn.

4. The film or pellet of any one of the previous claims, wherein the starch of the retrogradation-resistant starch comprising film comprises an amylose to amylopectin weight ratio between 40:60 to 0:100.

5. The film or pellet of any one of the previous claims, wherein the starch of the retrogradation-resistant starch comprising film comprises a blend of starches with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100.

6. The film or pellet of any one of the previous claims, wherein the starch of the retrogradation-resistant starch comprising film comprises a modified starch with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100.

7. The film or pellet of any one of the previous claims, wherein the starch of the retrogradation-resistant starch comprising film is a blend of modified starches with a combined weight ratio of amylose to amylopectin between 40:60 to 0:100.

8. The film or pellet of any one of the previous claims, wherein the starch present in the retrogradation-resistant starch comprising film is a naturally occurring starch, a thermoplastic starch, an alkyl etherized starch, carboxyalkyl etherized starch, hydroxyalkyl etherized starch having a hydroxyalkyl group having 2 to 6 carbon atoms, and synthetic starches.

9. The film or pellet of any one of the previous claims, wherein the starch of the retrogradation-resistant starch comprising film comprises a combination of a first starch having an amylose to amylopectin weight ratio between 40:60 to 0:100 and a second starch having an amylose to amylopectin weight ratio between 40:60 to 0:100, where at least one of the first starch and the second starch, independently, is unmodified, modified, synthetic, thermoplastic, or crosslinked.

10. The film or pellet of any one of the previous claims, wherein the molecular weight modifier is one or more of modified microfibri I lated celluloses, nanofi bril lated celluloses, modified nanofibrillated celluloses, sugar alcohols, dextrins, maltodextrins, synthetic and natural layered silicate clays, montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof.

11. The film or pellet of any one of the previous claims, wherein the molecular weight modifier is one or more of at least partially exfoliated or at least partially intercalated montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof.

12. The film of any one of the previous claims, wherein the molecular weight modifier is one or more of montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, and volkonskoite, in combination with a surfactant, an anionic surfactant, a zwitterionic compound, a zwitterionic polymer or copolymer, a polyampholyte compound, a polyampholyte polymer, urea or combinations thereof.

13. The film or pellet of any one of the previous claims, wherein the weight ratio of the starch of the retrogradation-resistant starch comprising film to the molecular weight modifier is between 50:1 to 1:50.

14. The film or pellet of any one of the previous claims, further comprising glycerol, polyvinyl alcohol, polyvinyl alcohol copolymer, or combinations thereof.

15. The film or pellet of any one of the previous claims, further comprises one or more components selected from the group consisting of impact modifiers, plasticizers, plasticizer compatibilizers, lubricants, release agents, fillers, extenders, cross-linking agents, antiblocking agents, antioxidants, detackifying agents, antifoams, nanoparticles, bleaching agents, surfactants, biocides, antimicrobials, pigments, and combinations or reaction products thereof.

16. A sustainable fluid-fillable air cushion comprising the retrogradation-resistant starch comprising film of any one of the previous claims.

17. A repupable mailer comprising the comprising the retrogradation-resistant starch comprising film of any one of the previous claims.

18. A process for producing a retrogradation-resistant starch film or pellet, the method comprising: continuously or semi-continuously metering into mixing or extrusion equipment a starch, a modified starch, a thermoplastic starch, or combination, polyvinyl alcohol polymer, and a molecular weight modifier; continuously mixing the composition in the mixing or extrusion equipment; and continuously discharging a retrogradation-resistant starch comprising film or pellet.

19. The process of claim 18, wherein the molecular weight modifier is one or more of at least partially exfoliated or at least partially intercalated montmorillonite, bentonite, beidellite, mica, hectorite, saponite, nontronite, sauconite, vermiculite, ledikite, magadite, kenyaite, stevensite, volkonskoite, and combinations thereof.

20. The process of any one of claims 18-19, wherein the molecular weight modifier is one or more of at least partially exfoliated or at least partially intercalated bentonite salt of an alkaline metal, alkaline earth metal, and combinations thereof.

21. The process of any one of claims 18-20, further comprising adding additional materials to the compounding section.

22. The process of any one of claims 18-21, wherein the additional materials comprise solid, liquid or gaseous materials.

23. The process of any one of claims 18-22, wherein the solid, liquid or gaseous materials are selected from the group consisting of thermoplastic elastomers, resins, extenders, activators, anti-degradents, blowing agents, crosslinkers and mixtures thereof.