WO2009061325A1

WO2009061325A1 - Low noise thermoplastic vulcanizate (tpv) support roller

Info

Publication number: WO2009061325A1
Application number: PCT/US2007/084291
Authority: WO
Inventors: Baojiu Lin
Original assignee: Advanced Elastomer Systems LP
Current assignee: Advanced Elastomer Systems LP
Priority date: 2007-11-09
Filing date: 2007-11-09
Publication date: 2009-05-14
Anticipated expiration: 2010-05-09

Abstract

A support roller and dryer using the same are provided. The roller can include a hub, a ring concentrically disposed about the hub, a first thermoplastic elastomer disposed between the hub and the ring, and a second thermoplastic elastomer disposed about the ring. The dryer can include a drum for containing one or more items of clothing and one or more support rollers in communication with the drum.

Description

LOW NOISE THERMOPLASTIC VULCANIZATE (TPV) SUPPORT ROLLER

BACKGROUND OF THE INVENTION Field of the Invention

[0001] Embodiments of the present invention generally relate to roller bearings for belt-driven appliances. More particularly, the embodiments relate to rollers for supporting a drum in a clothes dryer.

Description of the Related Art

[0002] Support rollers for clothing dryer drums are made of a rubber material that is arranged on a single, rigid plastic or metal hub much like a tire. The rubber material is typically a thermoplastic elastomer (TPE) or thermoset rubber (TSR). The structure of the roller is typically incapable of stress and vibration dissipation. Over time, the rubber material loses integrity and flattens. Such flat spots can create undesirable running noise and/or vibration. Static loads and/or varying thermal cycles are often the cause of the loss in integrity resulting in the flat spots.

[0003] There is a need, therefore, for a new support roller that does not flatten and is capable of dissipating stress and vibration, thereby eliminating run noise and providing a smoother operation.

SUMMARY OF THE INVENTION

[0004] A support roller and dryer using the same are provided. In at least one specific embodiment, the roller can include a hub, a ring concentrically disposed about the hub, a first thermoplastic elastomer disposed between the hub and the ring, and a second thermoplastic elastomer disposed about the ring.

[0005] In at least one specific embodiment, the dryer can include a drum for containing one or more items of clothing and one or more support rollers in communication with the drum. Each roller can include a hub, a ring concentrically disposed about the hub, a first thermoplastic elastomer disposed between the hub and the ring, and a second thermoplastic elastomer disposed about the ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

[0007] Figure 1 depicts a schematic of an illustrative clothes dryer having one or more support rollers, according to one or more embodiments described.

[0008] Figure 2 depicts a schematic plan view of an illustrative support roller, according to one or more embodiments described.

[0009] Figure 3 depicts a schematic plan view of an illustrative skin layer, according to one or more embodiments described.

[0010] Figure 4 depicts a schematic plan view of an illustrative support ring, according to one or more embodiments described.

[0011] Figures 5 and 5 A depict isometrics an illustrative soft ring, according to one or more embodiments described.

[0012] Figure 6 depicts a schematic plan view of an illustrative hub, according to one or more embodiments described.

[0013] Figure 7 depicts a schematic side view of another illustrative support roller.

[0014] Figures 8, 9, and 10 depict isometrics of illustrative support rollers having varying internal, strength designs, according to one or more embodiments described.

DETAILED DESCRIPTION

[0015] A detailed description will now be provided. Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims. Each of the inventions will now be described in greater detail below, including specific embodiments, versions and examples, but the inventions are not limited to these embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the inventions, when the information in this patent is combined with available information and technology.

[0016] Figure 1 depicts a schematic of an illustrative clothes dryer 100 having one or more support rollers, according to one or more embodiments. The dryer 100 can be powered by gas and/or electricity. In one or more embodiments, the dryer 100 can include an external housing 110 having an opening 115 disposed therethrough. A door 120 can be disposed on the housing 110 to provide access through the opening 115 to a rotatable drum 130 disposed within the housing 110.

[0017] The dryer 100 can further include a motor 150 disposed on a motor support 160. As mentioned above, the motor 150 can be gas or electric driven. The motor 150 can include a drive shaft 170 connected to a drive pulley 180. The drive pulley 180 and the drum 130 can be wrapped by a belt (not shown) so that the motor 150 can rotate the shaft 170 and the pulley 180, rotating the belt and the drum 130. A control panel 190 can be disposed on an upper surface of the dryer 100 for controlling the temperature, speed, duration, and other settings for the dryer operation.

[0018] In one or more embodiments, the drum 130 can be disposed on one or more support rollers (two are shown) 140. The support rollers 140 can be disposed between the drum 130 and a lower panel of the housing 110. Any number of rollers 140 can be used. Preferable, two or four rollers 140 are used to support the drum 130. Although not shown, the lower surface of the drum can include an indentation that serves as a track or guide for the rollers 140.

[0019] Figure 2 depicts a schematic plan view of an illustrative support roller according to one or more embodiments. Figure 2 depicts a schematic of an illustrative roller assembly 140 according to one or more embodiments. The roller 140 can include one or more skin layers 210, one or more support rings 220, one or more soft rings 230, one or more hubs 240, and an inner bearing 250. In at least one specific embodiment, the hub 240 can be disposed on an outer surface or diameter of the inner bearing 250. The soft ring 230 can be disposed on an outer surface or diameter of the hub 240. The support ring 220 can be disposed on the soft ring 230 and the skin layer 210 about the support ring 220. In one or more embodiments, the order of the inner components, i.e. the support ring 220, soft ring 230, and hub 240, can be changed or altered so long as the rings 220, 230 and 240 are disposed between the inner bearing 250 and the skin layer 210.

[0020] The inner bearing 250 can be any device or assembly capable of rotation. Such bearings are well known in the art, and are typically made of metal. Illustrative metals can include copper, nickel, aluminum, iron, zinc, steel, and alloys thereof.

[0021] The one or more hubs 240 ("first ring" or "rigid ring") can be adapted to provide strength to the roller 140 and/or to redistribute stress through the roller 140. Each ring 240 can have any thickness and outer diameter depending on strength requirements. When two are more rings 240 are used, each ring 240 can have the same or different thickness and/or constructed of the same or different material(s). A single ring 240 can also be used. The ring(s) 240 can be made of any material suitable to provide crush strength to the roller 140. For example, the ring(s) 240 can be made of a metal or metal alloy described above, and/or one or more thermoplastic resins. Suitable thermoplastic resins are discussed in more detail below.

[0022] The one or more soft rings 230 ("second ring") can be made of a material suitable to reduce vibration and dampen noise. For example, the soft ring(s) 230 can be made of one or more thermoplastic elastomers. Suitable elastomeric materials are discussed in more detail below. One, two, three, or four or more rings 230 can be disposed, i.e. layered, one on top of another. Each ring 230 can be made of the same or different material(s), and each ring 230 can have the same or different thickness(es). A single ring 230 can also be used.

[0023] The one or more support rings ("rigid floating ring") 220 can be adapted to redistribute the stress from the outer, skin layer 210 to the one or more inner rings 230, 240, and the bearing 250. The support ring 220 can be made of a material that is compatible with the adjoining skin layer 210 and soft ring 230. The support ring 220 can be made of any one or more thermoplastic resins and/or elastomeric materials. One, two, three, or four or more rings 240 can be disposed, i.e. layered, one on top of another. Each ring 220 can be made of the same or different material(s), and each ring 200 can have the same or different thickness(es). A single ring 220 can also be used. In one or more embodiments, a single support ring 220 made of one or more thermoplastic resins can be used. [0024] The one or more skin layers 210 provide the outermost layer of the roller 140. The skin layer(s) 210 are adapted to contact the outer surface of the drum 140 (shown in Figure 1). The skin layer(s) 210 can be made of one or more thermoplastic elastomers. Each skin layer 210 can have the same thickness and/or diameter, and can be made of the same or different thermoplastic elastomer.

[0025] The thermoplastic elastomers of the skin layers 210 and/or soft rings 230 are able to deform and dissipate more vibration energy translated from the drum 130 to the roller 140. As such, the roller 140 is capable of better sound performance, i.e. noise dampening. The thermoplastic elastomers of the skin layers 210 and/or soft rings 230 are also more flexible for adjusting the dynamic stiffness of the roller 140 to optimize the vibration reduction performance and to reduce running noise.

[0026] The support ring(s) 220 can be located between the thermoplastic elastomers of the skin layers 210 and/or soft rings 230 to provide structural integrity and strength to the roller 140. In one or more embodiments, the skin layer 210 can be made from a stiffer or harder grade thermoplastic elastomeric material to provide better contact with the rigid outer surface of the drum 130. In one or more embodiments, the soft ring 230 can be made from a softer grade thermoplastic elastomeric material to provide better vibration reduction and noise dampening than a harder TPE material.

[0027] In one or more embodiments, any one or more of the components/rings 210, 220, 230, 240 can include one or more mechanical locks 310 to engage or otherwise contact the adjoining ring(s) to provide better vibration dissipations and noise dampening. Figures 3-7 depict a schematic plan view of the rings 210, 22, 230, 240 having one or more mechanical locks 310 disposed thereon. The mechanical locks 310 can be an opening or aperture to allow a softer, flowable material of an adjoining ring, (e.g. 210 and/or 230) to flow through a more rigid, adjoining ring (e.g. 220 and/or 240). In one or more embodiments, an over-molding process can be used flow a softer material of rings 210 and/or 230 through a mechanical lock 310 of an adjoining ring 220 and/ or 240. As such, the mechanical locks 310 can allow the rings 210, 220, 230, 240, and bearing 250 to move together and act as a unitary assembly.

[0028] Still referring to Figures 3-6, each ring 210, 22, 230, 240 can include a profiled or contoured inner diameter and/or outer diameter. The profiled or contoured surface(s) can provide a tighter friction fit and/or contact with an adjoining ring. In one or more embodiments, the inner and/or outer diameters of the rings 210, 22, 230, 240 can be grooved, roughened, smoothed, and/or stepped to provide better contact and/or engagement with an adjoining ring.

[0029] Figures 8, 9, and 10 depict isometrics of illustrative support rollers having varying internal strength designs, according to one or more embodiments described. Three specific designs each having a varying degree of stiffness are depicted; however, it is to be understood that other designs and/or configurations can be equally effective. For example, Figure 8 depicts a roller having a T-type rib configuration 315 to provide high stiffness. Figure 9 depicts a roller having a ring-type configuration 320 to provide moderate stiffness. Each ring 320 can have a different thickness and/or made from a different material to tailor design its stiffness. Figure 10 depicts a roller having two or more open slots 325 for lower stiffness. As mentioned previously, other equally effective designs/configuration can be easily understood or obtained by those skilled in the art.

Thermoplastic Elastomer

[0030] In one or more embodiments, the thermoplastic elastomers can be the same or different. Each thermoplastic elastomer can include at least one rubber component, and at least one thermoplastic resin component. Each thermoplastic elastomer can also include one or more additive oils and/or one or more fillers. In one or more embodiments, each thermoplastic elastomer can also include one or more thermoset rubbers, such as ethylene-propylene copolymer rubber (EPR), ethylene-propylene-diene (EPDM) rubber, and EPDM-type rubbers.

[0031] The thermoplastic elastomer can be a thermoplastic vulcanizate composition. The term "thermoplastic vulcanizate composition" (also referred to as simply thermoplastic vulcanizate or TPV) is broadly defined as any material that includes a dispersed, at least partially vulcanized, rubber component; a thermoplastic resin component; and an additive oil. A TPV can also include other ingredients, other additives, or both.

Rubber Component

[0032] The rubber component can include an ethylene copolymer rubber. The "ethylene copolymer rubber" can be any ethylene-containing rubber such as ethylene-propylene copolymer rubber (EPR), ethylene-propylene-diene (EPDM) rubber, and EPDM-type rubbers, for example. An EPDM-type rubber can be a terpolymer derived from the polymerization of ethylene and at least one different monoolefϊn monomer having from 3 to 10 carbon atoms, preferably 3 to 4 carbon atoms, and at least one polyunsaturated olefin having from 5 to 20 carbon atoms. Those monoolefms desirably have the formula CH2=H-R where R is H or an alkyl of 1-12 carbon atoms and is preferably propylene. Desirably the repeat units from ethylene and the at least one monoolefm (and preferably from ethylene and propylene) are present in the polymer in weight ratios of 25:75 to 75:25 (ethylene propylene) and constitute from about 90 to about 99.6 weight percent of the polymer. The polyunsaturated olefin can be a straight chained, branched, cyclic, bridged ring, bicyclic, fused ring bicyclic compound etc., and preferably is a nonconjugated diene. Repeat units from the nonconjugated polyunsaturated olefin are preferably from about 0.4 to about 10 weight percent of the rubber.

Thermoplastic Resin Component

[0033] The thermoplastic resin component can include one or more olefinic thermoplastic resins. The "olefinic thermoplastic resin" can be any material that is not a "rubber" and that is a polymer or polymer blend considered by persons skilled in the art as being thermoplastic in nature, e.g., a polymer that softens when exposed to heat and returns to its original condition when cooled to room temperature. The olefinic thermoplastic resin can include one or more polyolefins, including polyolefin homopolymers and polyolefin copolymers. Illustrative polyolefins can be prepared from mono-olefin monomers including, but are not limited to, monomers having 2 to 7 carbon atoms, such as ethylene, propylene, 1-butene, isobutylene, 1-pentene, 1-hexene, 1-octene, 3-methyl-l-pentene, 4-methyl- 1-pentene, 5 -methyl- 1-hexene, mixtures thereof and copolymers thereof with (meth)acrylates and/or vinyl acetates. Preferably, the thermoplastic resin is unvulcanized or non cross-linked.

[0034] In one or more embodiments, the olefinic thermoplastic resin is or includes polypropylene. The term "polypropylene" as used herein broadly means any polymer that is considered a "polypropylene" by persons skilled in the art (as reflected in at least one patent or publication), and includes homo, impact, and random polymers of propylene. Preferably, the polypropylene used in the compositions described herein has a melting point above 110⁰C, includes at least 90 wt % propylene units, and contains isotactic sequences of those units. The polypropylene can also include atactic sequences or syndiotactic sequences, or both. In one or more embodiments, the olefinic thermoplastic resin is or includes isotactic polypropylene. Such olefinic thermoplastic resin components and methods for making the same are described in U.S. Pat. No. 6,342,565. [0035] The term "random polypropylene" as used herein broadly means a single phase copolymer of propylene having up to 9 wt %, preferably 2 wt % to 8 wt % of an alpha olefin comonomer. Preferred alpha olefin comonomers have 2 carbon atoms, or from 4 to 12 carbon atoms. Preferably, the alpha olefin comonomer is ethylene.

[0036] In one or more embodiments, the olefmic thermoplastic resin can include a "propylene copolymer." Preferably, the propylene copolymer contains at least 75 wt % of propylene-derived units; 75 wt % to 95 wt % of propylene-derived units or 80 wt % to 90 wt % of propylene- derived units. In one or more embodiments, the propylene copolymer can consist essentially of from 80 to 95 wt % repeat units from propylene and from 5 to 20 wt % of repeat units from one or more unsaturated olefin monomers having 2 or 4 to 12 carbon atoms, preferably ethylene.

[0037] In one or more embodiments, the propylene-derived units of the propylene copolymer have an isotactic triad fraction of about 65% to about 99%; about 70% to about 98%; or about 75% to about 97%. The propylene-derived crystallinity of the propylene copolymer can range from about 2% to about 65% or from about 5% to about 40%, as measured by Differential Scanning Calorimetry (DSC). In one or more embodiments, the propylene copolymer has a heat of fusion of 75 J/g or less, or 50 J/g or less, or 35 J/g or less, as measured using a DSC test, most preferably in accordance with ASTM E-794-95. The propylene copolymer can have a heat of fusion ranging broadly from 1.0 J/g to 90 J/g; or from 2 J/g to 40 J/g; or from 5 J/g to 35 J/g; or from 7 J/g to 25 J/g, Preferably, the propylene copolymer has a heat of fusion less than 45 J/g.

Additive Oil

[0038] The term "additive oil" includes both "process oils" and "extender oils." For example, the "additive oil" can include hydrocarbon oils and plasticizers, such as organic esters and synthetic plasticizers. Many additive oils are derived from petroleum fractions, and have particular ASTM designations depending on whether they fall into the class of paraffinic, naphthenic, or aromatic oils. Other types of additive oils include alpha olefinic synthetic oils, such as liquid polybutylene, e.g., products sold under the trademark PARAPOL™. Additive oils other than petroleum based oils can also be used, such as oils derived from coal tar and pine tar, as well as synthetic oils, e.g., polyolefm materials (e.g., SPECTRASYN™, supplied by ExxonMobil Petroleum & Chemical). Certain rubber components (e.g., EPDMs, such as VISTALON™ 3666) include additive oil that is preblended before the rubber component is combined with the thermoplastic. The type of additive oil utilized will be that customarily used in conjunction with a particular rubber component.

[0039] The additive oil can be present in amounts from about 5 to about 300 parts by weight per 100 parts by weight of the blend of the rubber and isotactic polypropylene components. The amount of additive oil may also be expressed as from about 30 to 250 parts, and more desirably from about 70 to 200 parts by weight per 100 parts by weight of the rubber component. Alternatively, the quantity of additive oil can be based on the total rubber content, and defined as the ratio, by weight, of additive oil to total rubber and that amount may in certain cases be the combined amount of process oil (typically added during manufacturing of TPV before and/or after curing the rubber) and extender oil (typically added in the rubber during its manufacturing). The ratio may range, for example, from about 0 to about 4.0/1. Other ranges, having any of the following lower and upper limits, may also be utilized: a lower limit of 0.1/1, or 0.6/1, or 0.8/1, or 1.0/1, or 1.2/1, or 1.5/1, or 1.8/1, or 2.0/1, or 2.5/1; and an upper limit (which may be combined with any of the foregoing lower limits) of 4.0/1, or 3.8/1, or 3.5/1, or 3.2/1, or 3.0/1, or 2.8/1. Larger amounts of additive oil can be used, although the deficit is often reduced physical strength of the composition, or oil weeping, or both. The ordinarily, skilled chemist will recognize which type of oil should be used with a particular rubber, and also be able to determine the amount (quantity) of oil.

Rubber Curing Agent

[0040] Any curative that is capable of curing or crosslinking the rubber component can be used. Depending on the rubber employed, certain curatives may be preferred. Illustrative curatives include, but are not limited to, phenolic resins, peroxides, maleimides, sulfur containing curatives, and silicon-containing curatives. Illustrative phenolic resins are described in U.S. Pat. Nos. 2,972,600; 3,287,440; 4,311,628; and 6,433,090. A preferred phenolic resin curative is an octylphenol-formaldehyde resin sold commercially as SP- 1045 from Schenectady International, Inc. Illustrative peroxide curatives are disclosed in U.S. Pat. No. 5,656,693. Useful silicon- containing curatives include silicon hydride compounds having at least two SiH groups. Illustrative silicon hydride compounds include, but are not limited to, methylhydrogen polysiloxanes, methylhydrogen dimethyl-siloxane copolymers, alkyl methyl polysiloxanes, bis(dimethylsilyl)alkanes, bis(dimethylsilyl)benzene, and mixtures thereof. Other Additives

[0041] The term "other additives" can include, but is not limited to, particulate fillers, lubricants, antioxidants, antiblocking agents, stabilizers, anti-degradants, anti-static agents, waxes, foaming agents, pigments, flame retardants, processing aids, adhesives, tackifiers, plasticizers, wax, and discontinuous fibers (such as wood cellulose fibers). Illustrative particulate fillers include carbon black, silica, titanium dioxide, calcium carbonate, colored pigments, clay, and combinations thereof. When non-black fillers are used, it may be desirable to include a coupling agent to compatibilize the interface between the non-black fillers and polymers. Desirable amounts of carbon black, or other colorants, when present, are from about 5 to about 250 parts by weight per 100 parts by weight of rubber.

Process Description

[0042] Any process for making TPVs may be employed. In one or more embodiments, the individual materials and components, such as the one or more rubber components, thermoplastic resin components, additive oils, curatives, other additives, etc., may be blended by melt-mixing in any order in a mixer heated to above the melting temperature of the thermoplastic resin component.

[0043] The one or more components, thermoplastic resin components, and curing agents can be added to a heated mixer as individual feed streams, as a tumbled blend, or as a masterbatch. The one or more thermoplastic resin components can be added before cure or divided in any proportions between before cure, during cure and after cure. The additive oil, e.g. process oil, can be added during mastication before cure, during cure, after cure, or divided in any proportions between before cure and after cure.

[0044] Preferably, the one or more curing agents are incorporated into the melt within a target range of melt temperature over a specified period of time (<120 seconds). The one or more curing agents can be added using any suitable technique, such as by injection as a solution in a compatible process oil, as a neat solid, as a neat melt, or as a masterbatch, for example.

[0045] One or more fillers or other additives can be introduced to the melt either before, during or after the cure. The additives, fillers or other compounds, which may interfere with the curing agents, should be added after curing reaches the desired level. Preferably, those additives are added to the melt as a slurry or paste in a compatible rubber process oil. Powder blends or masterbatches of these components can be prepared in a wax or polymer carrier to facilitate metering and mixing. Following the cure and sufficient mixing of the melt, the melt blend can be processed to form an elastomeric structure using any one or more of the following techniques: milling, chopping, extrusion, pelletizing, injection molding, or any other desirable technique. Additional details for making TPV compositions are described in U.S. Pat. No. 4,594,390.

Thermoplastic Resins

[0046] Suitable thermoplastic resins can include propylene homopolymers, propylene copolymers, ethylene homopolymers, ethylene copolymers, and or any one or more of the following polymer resins: a) polyamide resins such as nylon 6 (N6), nylon 66 (N66), nylon 46 (N46), nylon 11 (Ni l), nylon 12 (N 12), nylon 610 (N610), nylon 612 (N612), nylon 6/66 copolymer (N6/66), nylon 6/66/610 (N6/66/610), nylon MXD6 (MXD6), nylon 6T (N6T), nylon 6/6T copolymer, nylon 66/PP copolymer, nylon 66/PPS copolymer; b) polyester resins such as polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyethylene isophthalate (PEI), PET/PEI copolymer, polyacrylate (PAR), polybutylene naphthalate (PBN), liquid crystal polyester, polyoxalkylene diimide diacid/polybutyrate terephthalate copolymer and other aromatic polyesters; c) polynitrile resins such as polyacrylonitrile (PAN), polymethacrylonitrile, acrylonitrile-styrene copolymers (AS), methacrylonitrile-styrene copolymers, methacrylonitrile- styrene-butadiene copolymers; and acrylonitrile-butadiene-styrene (ABS); d) polymethacrylate resins such as polymethyl methacrylate and polyethylacrylate; e) cellulose resins such as cellulose acetate and cellulose acetate butyrate; f) fluorine resins such as polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), polychlorofluoroethylene (PCTFE), and tetrafluoroethylene/ethylene copolymer (ETFE); g) polyimide resins such as aromatic polyimides; h) polysulfones; i) polyacetals; j) polyactones; k) polyphenylene oxides and polyphenylene sulfides; 1) styrene-maleic anhydrides; m) aromatic polyketones, n) polycarbonates (PC); o) elastomers such as ethylene -propylene rubber (EPR), ethylene propylene-diene monomer rubber (EPDM), styrenic block copolymers (SBC), polyisobutylene (PIB), butyl rubber, neoprene rubber, halobutyl rubber and the like); and p) mixtures of any and all of a) through o) inclusive.

[0047] In one or more embodiments above or elsewhere herein, the thermoplastic resin can include one or more fillers for added strength. Fillers can be present in an amount of from 0.001 wt% to 50 wt% in one embodiment based upon the weight of the composition and from 0.01 wt% to 25 wt% in another embodiment, and from 0.2 wt% to 10 wt% in yet another embodiment. Desirable fillers include but are not limited to titanium dioxide, silicon carbide, silica (and other oxides of silica, precipitated or not), antimony oxide, lead carbonate, zinc white, lithopone, zircon, corundum, spinel, apatite, Barytes powder, barium sulfate, magnesiter, carbon black, graphite, dolomite, calcium carbonate, sand, glass beads, mineral aggregates, talc, and hydrotalcite compounds of the ions Mg, Ca, or Zn with Al, Cr or Fe and CO3 and/or HPO₄, hydrated or not; quartz powder, hydrochloric magnesium carbonate, short glass fiber, long glass fiber, glass fibers, polyethylene terephthalate fibers, wollastonite, mica, carbon fiber, nanoclays, nanocomposites, magnesium hydroxide sulfate trihydrate, clays, alumina, and other metal oxides and carbonates, metal hydroxides, chrome, phosphorous and brominated flame retardants, antimony trioxide, silicone, and any combination and blends thereof. Other illustrative fillers can include one or more polypropylene fibers, polyamide fibers, para-aramide fibers (e.g. KEVLAR™ or TWARON™), meta-aramide fibers (e.g. NOMEX™), polyethylene fibers (e.g. DYNEEMA™), and combinations thereof.

[0048] The thermoplastic resin can also include a nanocomposite, which is a blend of polymer with one or more organo-clays. Illustrative organo-clays can include one or more of ammonium, primary alkylammonium, secondary alkylammonium, tertiary alkylammonium, quaternary alkylammonium, phosphonium derivatives of aliphatic, aromatic or arylaliphatic amines, phosphines or sulfides or sulfonium derivatives of aliphatic, aromatic or arylaliphatic amines, phosphines or sulfides. Further, the organo-clay can be selected from one or more of montmorillonite, sodium montmorillonite, calcium montmorillonite, magnesium montmorillonite, nontronite, beidellite, volkonskoite, laponite, hectorite, saponite, sauconite, magadite, kenyaite, sobockite, svindordite, stevensite, vermiculite, halloysite, aluminate oxides, hydrotalcite, illite, rectorite, tarosovite, ledikite and/or florine mica.

[0049] When present, the organo-clay is preferably included in the nanocomposite at from 0.1 to 50 wt%, based on the total weight of the nanocomposite. The stabilization functionality may be selected from one or more of phenols, ketones, hindered amines, substituted phenols, substituted ketones, substituted hindered amines, and combinations thereof. The nanocomposite can further comprise at least one elastomeric ethylene-propylene copolymer, typically present in the nanocomposite at from 1 to 70 wt%, based on the total weight of the nanocomposite.

[0050] The thermoplastic resin can be a reinforced polypropylene (PP). Particularly preferred is a PP reinforced with a polyethylene-terethalate (PET) fiber or any other material that is light weight and provides a good balance of stiffness, impact strength, and has a low coefficient of linear thermal expansion (CLTE).

[0051] In one or more embodiments above or elsewhere herein, any polymeric material and thermoplastic resin can be impact modified to provide improved impact resistance. Impact modifiers include, but are not limited to plastomers, EPR, EPDM, and may be used in combination with compatibilizers like, but not limited to maleated polypropylene, maleated polyethylene and other maleated polymers, hydroxilated polypropylene and other hydroxilated polymers, derivatives thereof, and any combination thereof.

[0052] In one or more embodiments above or elsewhere herein, the thermoplastic resin can contain a plastomer, preferably a propylene plastomer blend. The term "plastomer" as used herein refers to one or more polyolefm polymers and/or copolymers having a density of from 0.85 g/cm³ to 0.915 g/cm³ according to ASTM D4703 Method B or ASTM D 1505, and a melt index (MI) between 0.10 dg/min and 30 dg/min according to ASTM D 1238 at 190⁰C, 2.1 kg). Preferred plastomers have a MI of between 0.10 dg/min and 20 dg/min in one embodiment, and from 0.2 dg/min to 10 dg/min in another embodiment, and from 0.3 dg/min to 8 dg/min in yet another embodiment as measured by ASTM D 1238 (190⁰C). Preferred plastomers can have an average molecular weight of from 10,000 to 800,000 in one embodiment, and from 20,000 to 700,000 in another embodiment. The molecular weight distribution (Mw/Mn) of desirable plastomers ranges from 1.5 to 5 in one embodiment, and from 2.0 to 4 in another embodiment. The 1% secant flexural modulus (ASTM D 790) of preferred plastomers range from 10 MPa to 150 MPa in one embodiment, and from 20 MPa to 100 MPa in another embodiment. Further, a preferred plastomer has a melting temperature (Tm) of from 30⁰C to 80⁰C (first melt peak) and from 50⁰C to 125°C (second melt peak) in one embodiment, and from 40⁰C to 70⁰C (first melt peak) and from 50⁰C to 100⁰C (second melt peak) in another embodiment.

[0053] In one or more embodiments above or elsewhere herein, the plastomer can be a copolymer of ethylene derived units and at least one of a C3 to C₁₀ α-olefm derived units. Preferably, the copolymer has a density less than 0.915 g/cm³. The amount of comonomer (C₃ to Cio alpha-olefm derived units) present in the plastomer ranges from 2 wt% to 35 wt% in one embodiment, and from 5 wt% to 30 wt% in another embodiment, and from 15 wt% to 25 wt% in yet another embodiment, and from 20 wt% to 30 wt% in yet another embodiment. [0054] In one or more embodiments above or elsewhere herein, the plastomer can be one or more metallocene catalyzed copolymers of ethylene derived units and higher alpha-olefm derived units, such as propylene, 1-butene, 1-hexene and 1-octene. Preferably, the plastomer contains enough of one or more of those comonomer units to yield a density between 0.860 g/cm and 0.900 g/cm³. Examples of commercially available plastomers include: EXACT™ 4150, a copolymer of ethylene and 1-hexene, the 1-hexene derived units making up from 18 wt% to 22 wt% of the plastomer and having a density of 0.895 g/cm³ and MI of 3.5 dg/min (available from ExxonMobil Chemical Company); and EXACT™ 8201, a copolymer of ethylene and 1-octene, the 1-octene derived units making up from 26 wt% to 30 wt% of the plastomer, and having a density of 0.882 g/cm³ and MI of 1.0 dg/min (available from ExxonMobil Chemical Company).

[0055] Preferred blends can include of from about 15%, 20% or 25% to about 80%, 90% or 100% polymer by weight; optionally of from about 0%, 5%, or 10% to about 35%, 40%, or 50% filler by weight, and optionally of from about 0%, 5%, or 10% to about 35%, 40%, or 50% plastomer by weight. In one or more embodiments, a preferred blend contains one or more polymers described in an amount ranging from a low of about 15%, 20% or 25% to a high of about 80%, 90% or 100% polymer by weight. In one or more embodiments, a preferred blend contains at least about 1%, 5%, 10%, 15%, or 20% plastomer by weight. In one or more embodiments, a preferred blend contains at least about 1%, 5%, 10%, 15%, or 20% filler by weight.

[0056] Preferably, blends for use herein can have a tensile strength of at least 6,500 MPa, at least 7,500 MPa, or at least 9,000 MPa. Further, preferred blends will have a flexural modulus of 1,750 MPa or more, such as about 1,800 MPa or more, or more than about 2,000 MPa.

[0057] Certain embodiments and features have been described using a set of numerical upper limits and a set of numerical lower limits. It should be appreciated that ranges from any lower limit to any upper limit are contemplated unless otherwise indicated. Certain lower limits, upper limits and ranges appear in one or more claims below. All numerical values are "about" or "approximately" the indicated value, and take into account experimental error and variations that would be expected by a person having ordinary skill in the art.

[0058] Various terms have been defined above. To the extent a term used in a claim is not defined above, it should be given the broadest definition persons in the pertinent art have given that term as reflected in at least one printed publication or issued patent. Furthermore, all patents, test procedures, and other documents cited in this application are fully incorporated by reference to the extent such disclosure is not inconsistent with this application and for all jurisdictions in which such incorporation is permitted.

[0059] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

Claims:What is claimed is:

1. A support roller, comprising: a hub; a ring concentrically disposed about the hub; a first thermoplastic elastomer disposed between the hub and the ring; and a second thermoplastic elastomer disposed about the ring.

2. The support roller of claim 1 , wherein the ring is rigid.

3. The support roller of claim 1, wherein the first thermoplastic elastomer is made of the same material as the second thermoplastic elastomer.

4. The support roller of claim 1, wherein the first thermoplastic elastomer is made of a different material as the second thermoplastic elastomer.

5. A dyer, comprising: a drum for containing one or more items of clothing; one or more support rollers in communication with the drum, wherein each roller comprises: a hub; a ring concentrically disposed about the hub; a first thermoplastic elastomer disposed between the hub and the ring; and a second thermoplastic elastomer disposed about the ring.

6. The dryer of claim 5, wherein the ring is rigid.

7. The dryer of claim 5, wherein the first thermoplastic elastomer is made of the same material as the second thermoplastic elastomer.

8. The dryer of claim 5, wherein the first thermoplastic elastomer is made of a different material as the second thermoplastic elastomer.