WO2025049809A2 - Bio-based fast reheat additive for polymers - Google Patents

Abstract

Disclosed herein are polymer composites may include one or more hydrothermal carbon (HTC) materials as a fast reheat (FRH) additive for various polymer materials. In demonstrative examples, polypropylene-HTC composites exposed to infra-red radiation showed an increase in heat reabsorption on their surfaces due to the presence of HTC, providing for faster reheating capability when processing polymers or materials that include HTC.

Description

BIO-BASED FAST REHEAT ADDITIVE FOR POLYMERS

CROSS-REFERENCE

[0001] This application claims the benefit of U.S. Provisional Application No. 63/535,293, filed 29 August 2023, the contents of which is incorporated herein by reference in its entirety.

FIELD

[0002] The present disclosure relates to fast reheat (FRH) polymers.

BACKGROUND

[0003] Carbon from various sources has been used to absorb heat in, for example, advanced aerospace applications as well as in more common applications, such as discarded packaging applications. Multiple forms of carbon, such as activated carbon, amorphous carbon, and graphene are used as additives in polymer production to speed up the heating rate of the polymers during certain processing steps. These forms of carbon are commonly referred to as fast reheat (FRH) additives. FRH carbon additives generally have their source material in coal. Currently, FRH additives are based on metals and several are based on multiple forms of carbon such as activated carbon, amorphous carbon, or even graphene.

[0004] FRH can be added to polymers through melt blending or during synthesis of the polymers, among other steps in common production of the polymers. Typical and even atypical carbon based FRH additives have their source material in coal and graphite. Efforts are underway to “clean” contaminants from coal and provide it in a suitable form, but the fossil fuel source and its related processing steps are undesirable and unsustainable. FRH carbon additives are typically added at low levels for several reasons. One of the main reasons that there is a limit on the color change tolerated by customers of FRH polymers such as polyethylene terephthalate (PET). Low levels are around 7 ppm and do not exceed 100 ppm.

[0005] Polypropylene (PP) has long been used for multiple thermoplastic applications. It serves well as a demonstration platform for thermoplastics since it tolerates open air processing and does not exhibit complicated cooling rate effects. It is also readily available and often selected for its low cost and mechanical properties. However, it is not as recyclable as PET, at least for the reason that it does not undergo chain extensions or solid-state polymerizations as PET does. It is also typically cloudy or opaque in appearance when molded. PP is therefore one example of a polymer material that would benefit from an HTC material additive for fast reheating. SUMMARY

[0006] Hydrothermal carbon (HTC) is primarily made of carbon, but prior to the present approach has not been considered as a potential carbon source for heat absorption. Its light weight and fluffy morphology could contribute to several benefits including being more likely to break into smaller particles and help contribute to dispersion and integration into a polymer matrix.

[0007] Applicants surprisingly found that carbon compounds derived from renewable biomass sources may be used to prepare fast heat polymer compositions.

[0008] Disclosed herein is a fast reheat polymer comprising: (a) a thermoforming polymer; and (b) an effective amount of a hydrothermal carbon (HTC) dispersed within the thermoforming polymer, wherein the HTC has an average particle size of from 2 micrometers to 40 micrometers, and wherein the effective amount of the HTC is an amount that increases a heat absorbance rate of the thermoforming polymer, as compared to a heat absorbance rate of the thermoforming polymer without the effective amount of the HTC. In some embodiments, the fast reheat polymer has a lower recrystallization rate, as compared to a recrystallization rate of the thermoforming polymer without the effective amount of the HTC. In some embodiments, the effective amount of the HTC is from 5 ppm to 100 ppm. In some embodiments, the fast reheat polymer has a lightness value (L*) greater than 80. In some embodiments, the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof. In some embodiments, the thermoforming polymer comprises a bio-derived polymer material.

[0009] Also disclosed herein is a fast reheat polymer comprising: (a) a thermoforming polymer; and (b) an effective amount of a hydrothermal carbon (HTC) dispersed within the thermoforming polymer, wherein the effective amount of the HTC is an amount that results in: (i) the fast reheat polymer having a lightness value (L*) greater than 80, and (ii) an increase in a heat absorbance rate of the thermoforming polymer, as compared to a heat absorbance rate of the thermoforming polymer without the effective amount of the HTC. In some embodiments, the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

[0010] Also disclosed herein is a polymer preform comprising a fast reheat polymer as described herein, wherein the fast reheat polymer has an increased heat absorbance rate, as compared to an otherwise comparable thermoforming polymer without an effective amount of an HTC described herein (e.g., an HTC derived from a renewable biomass). In some embodiments, the increased heat absorbance rate of the fast reheat polymer results in a faster reheating capability of the polymer preform, as compared a polymer preform without the effective amount of the HTC. In some embodiments, the faster reheating capability of the polymer preform results in decreased heating duration during downstream heating processing of the polymer preform, as compared to a heating duration of a polymer preform without the effective amount of the HTC. In some embodiments, the downstream heating processing comprises injection molding, thermoforming, blow-molding, or extrusion. In some embodiments, the downstream heating processes comprises thermoforming articles, such as polyethylene caps.

[0011] Also disclosed herein is an article that comprises a fast reheat polymer as described herein or a polymer preform as described herein. In some embodiments, the article is selected from bags, enclosures, bottles, bottle caps, apparel, a tent, an umbrella, outdoor covers, an electronic device, aircraft interior material, and surface material.

[0012] Also disclosed herein is a method of producing a fast-reheat polymer, the method comprising: (a) providing a thermoforming polymer and a hydrothermal carbon (HTC) derived from a renewable biomass, wherein the HTC has an average particle size of from 2 micrometers to 40 micrometers, and (b) dispersing an effective amount of the HTC into the thermoforming polymer, wherein the effective amount of the HTC is an amount that increases a heat absorbance rate of the thermoforming polymer, as compared to a heat absorbance rate of the thermoforming polymer without the effective amount of the HTC. In some embodiments, the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

[0013] Also disclosed herein is a method of thermoforming an article, the method comprising: (a) providing a fast reheat polymer that comprises: (i) a thermoforming polymer; and (ii) an effective amount of a fast reheat additive dispersed within the thermoforming polymer; and (b) thermoforming the fast reheat polymer into the article. Also disclosed herein is a method of thermoforming an article, the method comprising: (a) providing a fast reheat polymer that comprises: (i) a thermoforming polymer; and (ii) an effective amount of a hydrothermal carbon (HTC) dispersed within the thermoforming polymer, wherein the hydrothermal carbon (HTC) is derived from a renewable biomass; and (b) thermoforming the fast reheat polymer into the article. In some embodiments, the thermoforming of the article from the fast reheat polymer is performed with a lower heating duration, as compared to thermoforming the article using the thermoforming polymer without the effective amount of the HTC. In some embodiments, the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

[0014] Also disclosed herein is an article produced by a method of thermoforming as described herein.

[0015] These and other embodiments will be apparent to the person having an ordinary level of skill in the art in view of the description, the claims appended hereto, and the applications incorporated by reference herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Novel features of exemplary embodiments are set forth with particularity in the appended claims. A better understanding of the features and advantages will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the disclosed systems and methods are utilized, and the accompanying drawings of which:

[0017] FIG. 1 shows a blow molding oven used in some embodiments of the present disclosure. [0018] FIG. 2 is a photograph showing a polypropylene (PP) plaque exposed to heat in an oven. [0019] FIG. 3 shows an approach for temperature measurement following reheating of fast reheat polymer embodiments.

[0020] FIG. 4 shows the results of surface temperature increases for various embodiments of the present approach.

[0021] FIG. 5 is a photograph showing the outcome of a manual mixing of a hydrothermal carbon (HTC), PP, and a compatibilizer.

[0022] FIG. 6 is a photograph showing the outcome of an HTC, PP, and a compatibilizer run through an extruder prior to mixing.

[0023] FIG. 7 is a photograph showing a scaled up experiment of the example shown in FIG. 6.

[0024] FIG. 8 is a photograph showing an example of volume calculation based on liquid displacement.

[0025] FIG. 9A - FIG. 9D are microscopic images and digital analysis of cross sections of exemplary compositions to determine an HTC to PP ratio.

[0026] FIG. 10 is a graph showing stress/strain curves of HTC polymer samples.

[0027] FIG. 11 is a photograph showing HTC/PP and PP base samples after being fractured. [0028] FIG. 12 shows microscopic images of HTC/PP samples described herein, cut off a periphery section.

[0029] FIG. 13 shows microscopic images of HTC/PP samples described herein, at fracture lines. [0030] FIG. 14 shows comparative microscopic images of HTC/PP samples described herein, with different HTC percentages.

[0031] FIG. 15 is a photograph showing instruments and extrusion products of methods described herein.

[0032] FIG. 16 is a photograph showing images used to determine area measurements of polypropylene.

[0033] FIG. 17A - FIG. 17C are photographs showing samples of non-machine ground HTC (FIG. 17A), machine ground HTC (FIG. 17B), and carbonized HTC (FIG. 17C).

[0034] FIG. 18A - FIG. 18D shows scanning electron microscopy (SEM) images of exemplary HTC samples.

DETAILED DESCRIPTION

[0035] The following description is of the best currently contemplated mode of carrying out exemplary embodiments of the present approach. The description is not to be taken in a limiting sense, and is made merely for the purpose of illustrating the general principles described herein.

[0036] The following description illustrates embodiments of the present approach in sufficient detail to enable practice of the present approach. Although the present approach is described with reference to some embodiments, it should be appreciated that the present approach can be embodied in different forms, and this description should not be construed as limiting any appended claims to the embodiments set forth herein, rather, these embodiments are provided so that this disclosure will be through and complete, and will fully convey the scope of the present approach to those skilled in the art.

Definitions

[0037] The section headings used herein can be for organizational purposes and are not to be construed as limiting the subject matter described. In some cases, the sectional headings may not be constructed as limiting the subject matter described.

[0038] The terminology used in the description of embodiments of the present approach is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0039] As used in the specification and claims, the singular form “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise. The present approach encompasses numerous alternatives, modifications, and equivalents as will become apparent from consideration of the following detailed description.

[0040] The term “about” or “approximately” as used herein when referring to a measurable value such as an amount or concentration and the like and, unless stated otherwise, is meant to encompass variations of ±20%, which includes ±10%, ±5%, ±1 %, ±0.5%, or even ±0.1 % of the specified amount. A range provided herein for a measurable value may include any other range and/or individual value therein.

[0041] As used herein, the term “comprising” is intended to mean that the compositions and methods include the recited elements, but do not exclude others. “Consisting essentially of’ when used to define compositions and methods, shall mean excluding other elements of any essential significance to the combination for the intended use and those that do not materially affect a basic and novel characteristic(s). Thus, the term “consisting essentially of’ as used herein should not be interpreted as equivalent to “comprising.” A composition consisting essentially of the elements as defined herein would not exclude trace contaminants from the isolation and purification method and pharmaceutically acceptable carriers, such as phosphate buffered saline, preservatives, and the like. “Consisting of’ shall mean excluding more than trace elements of other ingredients and substantial method steps for administering the compositions of this disclosure. Embodiments defined by each of these transition terms are within the scope of this disclosure.

[0042] It will be understood that although the terms “first,” “second,” “third,” “(a),” “(b),” and “(c),” etc. may be used herein to describe various elements of the present approach, and the claims should not be limited by these terms. These terms are only used to distinguish one element of the present approach from another. Thus, a first element discussed below could be termed an element aspect, and similarly, a third without departing from the teachings of the present approach. Thus, the terms “first,” “second,” “third,” “(a),” “(b),” and “(c),” etc. are not intended to necessarily convey a sequence or other hierarchy to the associated elements but are used for identification purposes only. The sequence of operations (or steps) is not limited to the order presented in the claims.

[0043] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the present application and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. In case of a conflict in terminology, the present specification is controlling. [0044] Also, as used herein, “and/or” refers to and encompasses any and all possible combinations of one or more of the associated listed items, as well as the lack of combinations when interpreted in the alternative (or).

[0045] Unless the context indicates otherwise, it is specifically intended that the various features of the present approach described herein can be used in any combination. Moreover, the present approach also contemplates that in some embodiments, any feature or combination of features described with respect to demonstrative embodiments can be excluded or omitted.

[0046] Having thus described certain embodiments of the present approach, it is to be understood that the scope of the appended claims is not to be limited by particular details set forth in the above description as many apparent variations thereof are possible without departing from the spirit or scope thereof as hereinafter claimed.

[0047] Contemporary FRH polymers utilizing activated carbon or graphite-based carbon material have been successful, but are derived from fossil fuels. Applicant surprisingly found that it would be advantageous to provide an FRH additive sourced from renewable biomass. Rather than activated carbon or other graphite-based carbons, the present approach provides polymers with a faster reheat performance using bio-derived carbon sources, such as HTC, HTC derivatives, and other carbon compounds obtained from HTC (e.g., graphene).

[0048] In addition to being derived from renewable biomass, HTC and its derivatives have additional advantages as FRH additives. For example, the natural nano- and micro-porosity of HTC leads to a frangible product in both native HTC and carbonized HTC. The natural porosity of HTC compounds makes them unexpectedly advantageous as small particles for the FRH application, particularly in the sub-micron range. This represents a considerable advantage over other carbon sources derived from fossil fuels. Early indications are that HTC produces a more turbostratic carbon relative to other carbon materials. The naturally smaller particles aid in allowing HTC to be used at a higher volume fractions with less of an impact of the L* value. In some embodiments, an L* is greater than 80. In some embodiments, and L* value is greater than 90.

[0049] In some embodiments, the FRH polymer composition may contain polymers, such as thermoforming polymers, and carbon compounds derived from renewable biomass. For example, HTC can be used as an additive to impart fast reheat performance to polyesters such as, for example, bio-based PET and PEF and their co-polyesters. Prior to the present approach, HTC and derivatives prepared from HTC have not been considered as fast reheat agents in PET, other polyesters, or other thermoforming polymers.

[0050] In some embodiments, the present approach provides for fast reheat polymer materials having one or more fast reheat additives incorporate with or dispersed with one or more polymers. In some embodiments, the FRH additive is an HTC additive. In some embodiments, the HTC additive is a bio-derived HTC additive. In some embodiments, the bio-based HTC additive is produced as described herein. In some embodiments, the present approach provides for fast reheat polymer materials having one or more HTC materials and one or more polymers. The HTC material is derived from renewable biomass. Polymers may be selected from, but not limited to thermoforming polymers such as polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polytetrafluoroethylene, and acrylonitrile butadiene styrene.

[0051] In some embodiments, the present approach may take the form of a method for preparing a fast reheat polymer material. One or more HTC materials may be dispersed in a polymer. The HTC material may be dispersed through a variety of techniques, such as, for example only, dry mixing with the polymer (and any other additives) prior to polymerization, or following polymerization but before reheating into the desired form (e.g., extruding, blow molding, etc.).

[0052] This disclosure also relates to bio-based polymers comprising bio-based carbonaceous material that allows for rapid heating of the polymer material, which is useful for downstream processes of the polymer material, such as procedures in which the polymer material is heated. The bio-based carbonaceous material, such as bio-based HTC, incorporated in polymers provides polymer compositions with an accelerated heat absorption and/or shorter reaction heating times, which is useful for downstream processes such as blow molding.

[0053] Under the present approach, HTC may be used as an HTC additive at higher doses than other carbon materials without negatively impacting the L* value. In some embodiments, HTC can be dosed in a range of 5 ppm to 10 ppm. In some embodiments, HTC can be dosed above 10 ppm. In some embodiments, HTC can be dosed above 20 ppm. In some embodiments, HTC can be dosed upwards of 25 ppm. In some embodiments, the HTC dosing results in a reheat performance double or triple the performance of typical carbon additives that can only be dosed at about 7 ppm before an unacceptable decrease in the L* value.

[0054] The present approach relates to the development of the first bio-based PET and other commonly used polymers, integral to the shift to a carbon-negative polymer resin. To that end, multiple components are required to alter what is used today in industry. For example, today’s PET is derived from fossil fuel. The monoethylene glycol (MEG) purified terephthalic acid (PTA), and isophthalic acid (IPA), and other components of the polymer material come from crude oil.

[0055] The following description illustrates embodiments of the present approach in sufficient detail to enable practice of the present approach. Although the present approach is described with reference to these specific embodiments, it should be appreciated that the present approach can be embodied in different forms, and this description should not be construed as limiting any appended claims to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present approach to those skilled in the art.

[0056] Contemporary FRH polymers utilizing activated carbon or graphite-based carbon materials have had limited success. Rather than activated carbon or other graphite-based carbons, the present approach provides polymers with a faster reheat performance using bio-derived carbon sources, such as HTC, HTC derivatives, and other carbon compounds obtained from HTC (e.g., graphene). [0057] The present approach relates to the development of the first bio-based PET and other commonly used polymers, integral to the shift to a carbon-negative polymer resin. To that end, multiple components are required to alter what is used today in industry. For example, today’s PET is derived from fossil fuel. The monoethylene glycol (MEG), purified terephthalic acid (PTA), isophthalic acid (IPA), and other components of the polymer material come from crude oil.

[0058] Applicant has developed PTA through bio-derived CMF, a second generation source and the major component of PET. Other PET components remain to be sourced from renewable biomass sources. Along with PTA, 2,5-furandicarboxylic acid (FDCA) can also be produced from 5-chloromethylfurfural (CMF). There are efforts to replace fossil fuel -based IPA with FDCA as its confirmation in the polymer chain can provide a similar benefit to downstream processing that IPA provides and FDCA is inherently bio-based. This benefit is primarily the slowing of a crystallization rate of a polymer, such as PET.

[0059] Modern processing equipment, whether for injection, thermoforming, or blow-molding all benefit from a longer delay for PET to crystalize than is typical for the homo-polymer. Notably FDCA appears to slow crystallinity more aggressively than IPA, meaning less FDCA is needed for the same effect. That is beneficial in several ways including leaving the PET stream purer and reducing the fraction of the polymer depending on the more costly component. Whether or not there are additional benefits to aid recycling remains under investigation. The impact on DEG fraction should also be further characterized. Overall, this would mean that two of the three main components of PET could be replaced by molecules derived from renewable biomass (i.e., bio- TPA and FDCA).

[0060] In embodiments approaching FRH additive loads approaching 100 ppm, the carbon-based FRH material must have a small enough average particle size to be hard to see when dispersed in PET. On the extreme end, mono-layer graphene can be sub-nm in thickness but is more typically composed of nano-platelets involving a few sheets. Dispersion of FRH additives is also an important area of effort. Dispersion in MEG before polymer synthesis is one of the more straightforward routes to satisfactory performance.

[0061] Satisfactory FRH performance depends on the embodiment, but a typical desire is at least a 10% improvement in heating rate. Improvements on the order of 40% are possible, but those typically require dosing levels closer to 50 ppm with a particularly effective or high surface area particle. Efficiency is typically measured by energy required for a constant oven length rather than temperature measurements. Some faster processes cannot run without fast reheat properties. High speed, 0.5 liter light weight water bottles is an example of a more thermal efficiency demanding process. The preforms are so thin that IR light goes through rather than being absorbed in the bulk of the preform. A FRH additive helps the IR light be absorbed as heat in the bulk of the preform wall. Larger or thicker preforms can also benefit, however, as even heating is more likely with a well dispersed FRH additive in the PET.

[0062] Simply using jet milled HTC may be sufficient in small quantities with small particle sizes. In some embodiments, this can be done via, e.g., melt blending or synthesis. The product can start with a variety of carbon materials derived from renewable biomass, such as those produced by Origin Materials (West Sacramento, CA).

[0063] In some embodiments, the HTC materials forming polymer composites of the present disclosure are obtained by a method comprising: obtaining a parent carbonaceous material from a biomass feedstock and post-treating the parent carbonaceous material, which may comprise a portion of unreacted biomass feedstock, a macromolecular furan derivative, a cellulose compound, a lignin-based compound, or a combination thereof. In some embodiments, the parent carbonaceous material is post-treated to at least partially deoxygenate the parent carbonaceous material to provide the carbonaceous material according to the present disclosure. In some embodiments, post-treating the parent carbonaceous material does not comprise treating the parent carbonaceous material with an activating agent. The term “activating agent” refers to a reactive chemical agent that is affirmatively added to a parent carbonaceous material to impregnate the material to form activated carbon therefrom. Activating agents can include a base, an acid, a metal halide, a urea, or a combination thereof. The term “biomass feedstock” generally refers to any plant or plant-derived material made up of organic compounds relatively high in oxygen, such as carbohydrates, which can be used as a starting material to produce the carbonaceous material disclosed herein. In some embodiments, the biomass feedstock comprises lignin-free material. In some embodiments, the biomass feedstock comprises plant-based lignin-free material. Nonlimiting examples of the feedstock include glucose, glucans, cellulose, lignocellulose, hemicellulose, starch, sucrose, or any mixtures thereof. The term “carbonaceous material” generally refers to a material that comprises carbon and that has been obtained from a parent carbonaceous material via a post-treatment and has a lower oxygen content than the parent carbonaceous material. In some embodiments, the carbon is a majority component (e.g., carbon is greater than 80 wt.% of the carbonaceous material). In some embodiments, the carbonaceous material comprises a carbon content of greater than or equal to 85 wt.%, a surface area ranging from 150 m2/g to 500 m2/g, and an oil absorption value ranging from 50 g/100 g to 100 g/lOOg.

[0064] Dosing will depend on the entire polymer composition, but in prototype embodiments FRH additive loads were successful on the order of 7-100 ppm. It should be appreciated that the carbon material dose may be about, e.g., 10 ppm, 20 ppm, 30 ppm, 40 ppm, 50 ppm, 60 ppm, 70 ppm, 80 ppm, 90 ppm, 100 ppm, ± 5 ppm. Of course, it is foreseeable that a suitable carbon material dose for a specific embodiment falls outside of these ranges.

[0065] It should also be appreciated that the carbon material particle size is an important factor. Generally, a smaller particle size is less visible and has little or no interaction with thin films. For example, the carbon material particle size may be about, e.g., 10 microns, 20 microns, 30 microns, 40 microns, ± 5 microns. The carbon material particle size may be an average particle size. In some embodiments, average particle size is about 2 microns. In some embodiments, average particle size is about 3 microns. In some embodiments, average particle size is about 4 microns. In some embodiments, average particle size is about 5 microns. In some embodiments, average particle size is about 10 microns. In some embodiments, average particle size is about 15 microns. In some embodiments, average particle size is about 20 microns. In some embodiments, average particle sizes are about 40 microns and were determined to be useful without creating visible defects. In some embodiments, sub-micron average particle sizes were found to be beneficial. These dark particles on the IR spectrum absorb heat from the environment, such as, e.g., IR heat lamps, and then transfer the absorbed heat to the surrounding polymer matrix.

[0066] The present approach may be used with a wide variety of polymers, including, but not limited to, thermoforming polymers such as PEF, PET, PETF, PP, HDPE, among others.

[0067] In one example use case, the FRH resin is useful for forming polymer preforms that will be blow-molded into packing, bottles, and the like. FRH resins allow for smaller ovens and a faster process in blow molding, resulting in an overall increase in efficiency.

[0068] It should be appreciated that under the present approach, biomass-derived HTC and its derivatives allows for bio-derived PET, PEF and its co-polymers, etc., to produce a fully bio-based FRH resin and/or FRH additive.

[0069] Under the present approach, HTC can be compounded into polymers and rubber and absorb IR, resulting in a FRH resin. In some embodiments, HTC can be compounded into polymers and rubbers, resulting in a FRH resin that has a higher IR emissivity compared to comparable polymers and rubbers without the HTC. In some embodiments, HTC can be compounded into polymers and rubbers, resulting in a FRH resin that has a faster cooling rate compared to comparable polymers and rubbers without the HTC. In some embodiments, HTC can be compounded into polymers and rubbers, resulting in a FRH resin that has a faster heating rate compared to comparable polymers and rubbers without the HTC. In some embodiments, HTC can be compounded into polymers and rubbers, resulting in a FRH resin that has a lower density compared to comparable polymers and rubbers without the HTC. Without wishing to be bound by theory, the structure of HTC additives of the present disclosure can prevent full permeation of a polymer into its own pores, which then retains air in its polymer matrix and lightens the composite more than carbon alone. In some embodiments, the resulting FRH resin with a modified property disclosed herein is useful, for example in tire applications.

[0070] In some embodiments, HTC may be dispersed in a medium and introduced to a polymer resin composition. HTC particle size and carbonation derivatives can be modified to fine tune the FRH resin. A sieve and/or filter may be used to reduce the particle size distribution for a given HTC material.

[0071] In some embodiments, HTC is dispersed in a polymer or rubber to produce a FRH polymer with a tuned physical parameter. In some embodiments the tuned physical parameter is an increased surface area of the FRH polymer. In some embodiments the tuned physical parameter is an decreased particle size of the FRH polymer. In some embodiments the tuned physical parameter is decreased average particle size of the FRH polymer. In some embodiments the tuned physical parameter is tuned carbon content (%) of the FRH polymer. In some embodiments the tuned physical parameter is tuned hydroxide content (%) of the FRH polymer. In some embodiments the tuned physical parameter is tuned furan content (%) of the FRH polymer. In some embodiments the tuned physical parameter is tuned carbonyl content (%) of the FRH polymer. In some embodiments the tuned physical parameter is tuned carboxylic acid content (%) of the FRH polymer. In some embodiments the tuned physical parameter is tuned calcium or cation content (%) of the FRH polymer.

[0072] In some embodiments, HTC is dispersed in a polymer or rubber to produce a FRH polymer with a tuned reaction parameter. In some embodiments, the tuned reaction parameter comprises modifying one or more of the following parameters: reaction time; feedstock (e.g., glucose, cornstarch, fructose, white oak, loblolly Southern Pine, etc.); feedstock particle size; reaction temperature; organic/aqueous volumetric ratio; mass fraction; organic solvent requirement, salt or salt concentration requirement, or any combination thereof. [0073] In some embodiments, HTC is dispersed in a polymer or rubber to produce a FRH polymer with a tuned process parameter. In some embodiments, the tuned process parameters comprise modifying one or more of the following parameters: steam time, amount of organic phase remaining prior to steaming, percentage neutralization with calcium hydroxide, residence time in slurry-containing tank, or any combination thereof.

[0074] In some embodiments, the HTC carbonization parameters are modified by altering reaction time. In some embodiments, the HTC carbonization parameters are modified by altering reaction temperatures. Is some embodiments, the HTC carbonization parameters are modified by altering milling parameters of the HTC material.

[0075] In some embodiments of the present approach, polypropylene HTC composites were tested for rate of heat increase when exposed to infra-red radiation. An increase in heat absorption was observed on the surface of the parts due to the presence of HTC. This heat increase is expected due to the carbon content in HTC and it expected to be generally applicable to providing faster heating capability when processing polymers or materials of any type that would have HTC imbedded within. The results described in connection with this embodiment are initial results and further testing and analysis are ongoing.

Examples

[0076] An exemplary synthesis of HTC material of the present disclosure can be synthesized using the following steps.

[0077] Synthesis of wet parent carbonaceous material. Biomass to carbonaceous material reactions occurred in a pilot 80-gallon reactor, with a target reaction temperature range of 135-145 °C and reaction times of 10-24 minutes. Target concentrations of the aqueous phase were typically 2M HC1, 5.5 CaCh, and 13M total Cl. Feedstock mass fractions in the aqueous phase typically range from 10-23 wt% and consist of both single feedstocks (cornstarch or wood only) or blends of feedstocks (cornstarch and wood combined). The “aqueous phase” is defined as total water, CaCh, and HC1 in the reactor. Organic to aqueous ratios ranged from 1.6 to 2.2. Note that both hardwoods and softwoods of various species of wood have been tested. Process steps are similar with variations occurring in the specific amounts of raw materials added.

[0078] Drying and carbonization. 56 kg of wet parent carbonaceous material at 80 % wet basis (% w.b.) moisture content was placed in a furnace system. The system underwent nitrogen purge cycles to inert the furnace environment. Then, nitrogen was introduced into the system at a set flow rate (50 stand liters per minute (slpm)) and a slight positive pressure was maintained (760- 860 torr). The system was heated up to 175 °C at 2.5 °C/min followed by a 12-hour isothermal period for the drying step. The system was then heated up to 200 °C at 0.2 °C/min followed by a 2-hour isothermal period to confirm the material had dried. The system was then heated up to 530 °C at 2.75 °C/min followed by 2 hours of isothermal hold. The system was then ramped to 1000 °C at 7 °C/min with a 4-hour isothermal hold to ensure complete carbonization. The system was turned off and equipment was allowed to cool to ambient temperature, which took roughly 12 hours.

[0079] Jet-milling. In examples herein, 200 to 1200 g of carbonaceous material was fed to an alpine jet-mill at 1 to 5 kg/hr. Grind gas pressures of 70 to 110 psi and classifier speeds of 12,000 to 22,000 rpm were employed. A two-stage particle-collection system was employed, consisting of a cyclone and baghouse. Both the cyclone and baghouse fractions were collected and tested separately. It should be recognized that these conditions may depend on the mill used. For example, using larger feed rates with a mill having a larger classifier at different grind gas pressures and/or lower speeds may be used.

[0080] The following paragraphs describe some embodiments of the present approach. In some embodiments, a standard bank of oven lamps typically used for blow molding preforms was used at the heating source (FIG. 1). While configured for heating preforms, in this case the preforms were removed and a plaque of polypropylene (PP) or a polypropylene comprising hydrothermal carbon (PP-HTC composite) was held fixed in front of the heating lamps (FIG. 2). At set intervals, the plaque was briefly removed, and the surface temperature was measured using a laser assisted non-contact thermometer (FIG. 3) before continuing forward with another interval of heating to a higher temperature. The first set of intervals was 30 seconds. The plaque was briefly removed for less than 10 seconds, and the surface temperature was measured using a laser assisted non-contact thermometer before continuing forward with another interval of heating to a higher temperature. This required two lab personnel, one to heat the sample and another to measure and record the times and temperatures. These temperatures were recorded for three (3) sets of samples: (1) a baseline PP with no HTC; (2) a PP-HTC composite with approximately 50% HTC; and (3) a low loading version with less than 1% HTC (FIG. 4).

[0081] As shown in FIG. 3, a non-contact thermometer, such as a dual laser version with a spot size of 25 mm, an accuracy of ±1 °C, and a spectral response - infrared 8.0 to 14.0 um (FLIR Thermometer IR) was used for measurement of surface temperatures.

[0082] In this example the procedure used for the samples was as follows:

1. A minimum warm up period for the blow molding oven was 10 min. 2. A flat face of the sample being tested was selected and the same side was exposed at each interval.

3. A timer was set for timing the interval .

4. The sample was held within a heated part of the oven using tongs or plyers.

5. The sample was quickly removed to collect a temperature reading and the reading was recorded.

6. The timer was reset for timing the next interval, and the procedure repeated for the next interval, from step 4, until the number of intervals was finished.

7. The sample were closely observed for melting or deformation of the polymer material, and contact with the lamps or wall of the oven was avoided.

[0083] Surface temperature measurements obtained during the above procedure are shown in Table 1 below.

Table 1 Surface temperature measurements of samples

[0084] In these experiments, the temperature of the samples increased with exposure to heat lamps and that temperature increase accelerated in samples containing HTC as a filler in PP. There is a degree of uncertainty related to a consistent spot size for exposure, distance to the lamp, and precise measurement location. However, the technique used had been tested repeatedly in the laboratory for surface measurements on PET preforms, so the errors are within reason. The observed trend supports the validity of the results.

[0085] It is also important to note that the test is relevant to the use of FRH in preforms as the same type of heating apparatus used for these samples would be used to heat preforms.

[0086] As illustrated in FIG. 4, the graph of surface temperature versus time, clearly shows a useful trend of surface temperature increase with time and that that surface temperature increases more rapidly with increasing fractions of HTC. Without wishing to be bound by theory, Applicant contemplates that it would be useful to reduce and restrict the particle size of the HTC and more precisely measure the fraction of HTC, such as in the range below 1%.

[0087] At 60 seconds, even a small amount of HTC in PP showed performance enhancement in the order of 10%, which is indicative of the necessary performance given that oven heating of preforms typically exceeds 1 min and many preform ovens heat for much longer than 60 seconds. [0088] These temperature results confirm that HTC can be used to accelerate heat absorption in materials. Beyond polypropylene, it is expected that this same behavior would be observed in PET, HDPE, and other materials. These data show that HTC derived from renewable biomass may be used as an effective FRH additive in polymer materials.

[0089] The following paragraphs illustrate additional results obtained in further embodiments of the present approach.

[0090] In an experiment, as shown by the photograph in FIG. 5, a manual mixing of HTC, PP, and a compatibilizer (MAGPP) was undertaken before using a hot press. The heat/pressure in not high enough to provide sufficient flow to force mixing, despite the presence of the compatibilizer to facilitate such an effect. In another experiment, as shown in FIG. 6, the same mixture was run through an extruder prior to a heat press to facilitate mixing. The extruded filaments were then cut into small pieces to fit into a mold. The sample from this experiment was irregularly formed due to a pressure of 5 tons being applied. However, the sample was significantly more homogenous compared to the previous example and was qualitatively solid. The experiment was then scaled up to allow for further tests (as shown in FIG. 7).

Density

[0091] Density of the samples were calculated from weighing a small portion of each sample and using volume measurements derived via displacement of a liquid in a graduated cylinder (FIG. 8). Density was determined for an HTC/PP composite sample, a dry HTC powder, and a polypropylene (PP) sample, for comparison. The dry HTC sample was packed into the graduated cylinder and measured as a powder. The calculated densities are shown in Table 2, below.

Table 2 Calculated density values

For sample 1 PP: volume = 2 ml, mass = 1.8 g For sample 2 PP: volume = 3 ml; mass = 2.24 g For dry HTC: volume = 5 ml; mass = 3.72 g HTC to PP ratio measuring

[0092] An experiment was performed with the intention of producing a 50% HTC containing sample. Two methods were used for determining the ratio of HTC to PP. The first method was a calculation based on the differences in density using the equation shown below, and inserting the average values of the samples.

HTC > Ppp-pHTC/PP > 0.863-0.33

= 0.414 = 41%

PP Ppp~PHTC 0.863-0.744

[0093] A potential explanation for a lower HTC percentage other than a measuring error could have resulted from a quantity of sample material being left inside an extrusion barrel as residual material after extrusion, or voids in the sample material, which may deflate the density of the composite sample.

[0094] The second method was by digitally analyzing a cross section of a sample, and based on the percentage of dark versus light sections, measure the percentage of HTC to polypropylene. Multiple images were taken to mitigate any inaccuracy, as shown in Table 3, below, and FIG. 9A - FIG. 9D (with a greyscale fracture image shown on the left hand side, and a processed image of the fracture image on the right hand side, processed using contrast and binary filtering using ImageJ software).

Table 3. Percentage HTC as determined by digital analysis

[0095] The second method calculated an average of 58% HTC. The actual percentage is likely to be a value between the value determined by the two methods. In some embodiments, an increase in homogeneity of a sample will aid in measuring an actual ratio of HTC present in the sample. In some embodiments, the increase in homogeneity is achieved by changing the heat to pressure ratio to force flow. In some embodiments, the increase in homogeneity is achieved by increasing an amount of a compatibilizer.

Tensile testing

[0096] The HTC/PP composite sample prepared in this example was broken into two sections and subjected to tensile testing using an Instron machine. The results of the tests are shown in FIG. 10 and in Table 4 below, using PP samples produced for comparison.

Table 4. Tensile test results of HTC samples.

[0097] As shown in FIG. 11, HTC-PP and PP samples were photographed after being fractured and the material behaved and appeared to be brittle.

[0098] The density of the HTC-PP composite material was nearly two and a half times lower than the PP material, while maintaining a similar ultimate strength. This presents itself in the form of specific strength (weight-strength ratio = ultimate strength/density (specific strength)). r ;^> ~ 12.3/

[0099] In some embodiments, air pockets or voids in an HTC-PP composite material contribute to a decrease in specific strength. In some embodiments, a decrease in specific strength is due to inaccurate density measurements.

Microscopic images

[0100] HTC-PP composites samples were analyzed by microscopic imagery, taken from cutting sections off a periphery of the composites (FIG. 12). In some embodiments, using a grinder to break filaments into more granular pieces produces a material of a higher homogeneity. To verify that, some of the material in its filament form (prior to compression molding) was analyzed for HTC to polypropylene ratios and to quantitatively observe if the HTC distribution varies (see FIG.

13)

HTC-PP composite filaments

[0101] Sample filaments were analyzed as shown in FIG. 14. A good filament (left hand side of FIG. 14) appears similar to the surface of the final sample. A matrix shape of what appears to be polypropylene is present in a poor filament binding with HTC (right hand side of FIG. 14). Using a similar digital imaging processing tool, as used in FIG. 9 discussed above, the approximate percentage of HTC was calculated in a number of samples, as shown in Table 5, below. Table 5. Amount of HTC in filaments analyzed.

[0102] The data indicates that there may be some interesting properties by decreasing HTC content to 30% to 40%, where a portion of the tensile strength is recovered, but a specific strength is preserved.

Methods of extrusion and hot press

[0103] A composite sample production comprises the following steps:

1. Measuring out a 50-50 ratio of 60 g of polypropylene, 60 g of dry HTC, and 5% of the mass or 6 g of MAGPP (a compatibilizer).

2. Setting a filament extruder die, barrel, and heating zone to 190 °C, 180 °C, and 125 °C, respectively (as shown in FIG. 15).

3. Inserting material into the extruder and pushing the material through with more propylene, as needed.

4. Allowing the composite filament to collect at the end.

5. Cutting the extruded filaments into manageable pieces and setting in a mold.

7. Heating the material to 250 °C for 25 minutes.

8. Applying a pressure in a hot press, set to 1 ton for 5 minutes.

[0104] For the above examples, in order to measure an area of PP, a scale from a dial caliber was put into a frame aligned with the cross section of a sample, enabling the area to be converted from pixels to cm² (see FIG. 16). While it is not perfectly accurate, it was considered to be closer than making an assumption of constant thickness and width of the polypropylene samples. The calculated samples are shown in Table 6 below.

Table 6. Calculated results of PP area.

[0105] Without wishing to be bound by theory, Applicant contemplates using the above method to produce more refined and more uniform samples, increasing HTC to PP ratio in the samples, and alternating graph modulus values for different HTC percentages. The methods can be carried out with different base polymers and thermoforming polymers, such as, for example poly AB S, PET, and nylon. Additionally the type of HTC used can also be varied, to include, for example, HTC samples that have been milled or sieved, are wet, or are dry. In some embodiments, the HTC is a non-machine ground HTC, such as shown in FIG. 17A. In some embodiments, the HTC is a machine ground HTC, such as shown in FIG. 17B. In some embodiments, the HTC is a carbonized HTC, such as shown in FIG. 17C. Scanning electron microscopy (SEM) images of HTC samples are shown at FIG. 18A- FIG. 18D.

[0106] The present approach may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the claims of the application rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

[0107] While preferred embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will now occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the disclosure and that methods and structures within the scope of these claims and their equivalents be covered thereby.

Claims

CLAIMS What is claimed is:

1. A fast reheat polymer comprising:

(a) a thermoforming polymer; and

(b) an effective amount of a hydrothermal carbon (HTC) dispersed within the thermoforming polymer, wherein the HTC has an average particle size of from 2 micrometers to 40 micrometers, and wherein the effective amount of the HTC is an amount that increases a heat absorbance rate of the thermoforming polymer, as compared to a heat absorbance rate of the thermoforming polymer without the effective amount of the HTC.

2. The fast reheat polymer of claim 1, wherein the fast reheat polymer has a lower recrystallization rate, as compared to a recrystallization rate of the thermoforming polymer without the effective amount of the HTC.

3. The fast reheat polymer of claim 1 or 2, wherein the effective amount of the HTC is from 5 ppm to 100 ppm.

4. The fast reheat polymer of any one of claims 1-3, wherein the fast reheat polymer has a lightness value (L*) greater than 80.

5. The fast reheat polymer of any one of claims 1-4, wherein the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

6. The fast reheat polymer of any one of claims 1-5, wherein the thermoforming polymer comprises a bio-derived polymer material.

7. A fast reheat polymer comprising:

(a) a thermoforming polymer; and

(b) an effective amount of a hydrothermal carbon (HTC) dispersed within the thermoforming polymer, wherein the effective amount of the HTC is an amount that results in:

(i) the fast reheat polymer having a lightness value (L*) greater than 80, and (ii) an increase in a heat absorbance rate of the thermoforming polymer, as compared to a heat absorbance rate of the thermoforming polymer without the effective amount of the HTC.

8. The fast reheat polymer of claim 7, wherein the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

9. A polymer preform comprising the fast reheat polymer of any one of claims 1-8.

10. The polymer preform of claim 9, wherein the increased heat absorbance rate of the fast reheat polymer results in a faster reheating capability of the polymer preform, as compared a polymer preform without the effective amount of the HTC.

11. The polymer preform of claim 9 or 10, wherein the faster reheating capability of the polymer preform results in decreased heating duration during downstream heating processing of the polymer preform, as compared to a heating duration of a polymer preform without the effective amount of the HTC.

12. The polymer preform of claim 11, wherein the downstream heating processing comprises injection molding, thermoforming, blow-molding, or extrusion.

13. An article that comprises the fast reheat polymer of any one of claims 1-8, or the polymer preform of any one of claims 9-12.

14. The article of claim 13, wherein the article is selected from bags, enclosures, bottles, bottle caps, apparel, a tent, and umbrella, outdoor covers, an electronic device, aircraft interior material, and surface material.

15. A method of producing a fast-reheat polymer, the method comprising:

(a) providing a thermoforming polymer and a hydrothermal carbon (HTC) derived from a renewable biomass, wherein the HTC has an average particle size of from 2 micrometers to 40 micrometers, and

(b) dispersing an effective amount of the HTC into the thermoforming polymer, wherein the effective amount of the HTC is an amount that increases a heat absorbance rate of the thermoforming polymer, as compared to a heat absorbance rate of the thermoforming polymer without the effective amount of the HTC.

16. The method of claim 15, wherein the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

17. A method of thermoforming an article, the method comprising:

(a) providing a fast reheat polymer that comprises:

(i) a thermoforming polymer; and

(ii) an effective amount of a fast reheat additive dispersed within the thermoforming polymer; and

(b) thermoforming the fast reheat polymer into the article.

18. A method of thermoforming an article, the method comprising:

(a) providing a fast reheat polymer that comprises:

(i) a thermoforming polymer; and

(ii) an effective amount of a hydrothermal carbon (HTC) dispersed within the thermoforming polymer, wherein the hydrothermal carbon (HTC) is derived from a renewable biomass; and

(b) thermoforming the fast reheat polymer into the article.

19. The method of claim 18, wherein the thermoforming of the article from the fast reheat polymer is performed with a lower heating duration, as compared to thermoforming the article using the thermoforming polymer without the effective amount of the HTC.

20. The method of claim 19, wherein the thermoforming polymer comprises polypropylene, polyethylene, polyethylene furanoate, polyethylene terephthalate, polystyrene, polyamide, polyester, polylactic acid, polyhydroxyalkanoate, polycarbonate, polytetrafluoroethylene, poly acrylonitrile butadiene styrene, or any combination thereof.

21. An article produced by the method of any one of claims 17-20.