KR20070037746A - Polyolefin foam supplies - Google Patents

Abstract

Foam compositions comprising (1) ethylene acrylate copolymers and soft ethylene polymers or (2) ethylene acrylate copolymers, acid copolymers, ionomers of acid copolymers or combinations thereof and optionally soft ethylene polymers A composition that can be used as is disclosed. The ethylene acrylate copolymer includes repeating units derived from ethylene and alkyl acrylates. Acid copolymers include repeat units derived from ethylene and one or more unsaturated carboxylic acids, acid anhydrides, or monoesters of acids, or combinations of two or more thereof. Soft ethylene polymers include copolymers of ethylene and α-olefins, copolymers of ethylene and vinyl acetate, or combinations thereof.

Foam Composition, Ethylene Acrylate Copolymer

Description

Polyolefin Foam Supplies {POLYOLEFIN FOAMS APPLICATIONS THEREWITH}

The present invention relates to polymeric foam compositions such as crosslinked polymeric foam compositions and articles made therefrom.

Polyolefin materials include a variety of polymers, from semi-rigid polypropylene (PP) to soft ethylene polymers. It can be used to make a variety of foam products. Most polyolefin foams are closed bubble foams having buoyancy, elasticity, toughness, flexibility and resistance to compounds and grinding. Thus, polyolefin foams are useful in packaging, construction, insulation, sports, leisure and footwear articles.

Copolymers of ethylene and vinyl acetate (EVA) have been widely used as base resin polymers in foam articles for many years. Crosslinked EVA foam expanded with a chemical foaming agent provides a suitable balance of elasticity, durability, and other physical properties needed for sole articles of footwear. This property is provided at a low density, which is desirable for lighter weight shoes, and at a reasonable cost. EVA may exhibit limitations in achieving a balance of ductility (eg surface ductility), low permanent compression, and high elasticity. In addition, as the foaming process becomes increasingly single-step injection molded, it may be difficult to obtain balanced properties using EVA foam.

Foams made from ethylene acrylate copolymers (also referred to as ethylene-acrylic acid ester copolymers), such as ethylene-methyl acrylate copolymers (E / MA) with high MA content, are generally soft, low density and high elastic Has

EMA foams may have weak mechanical properties such as tear strength and tensile strength and may be difficult to crosslink.

There is a continuing need for the development of new products to expand the range of use of known polyolefin foams, such as the foam footwear market, to reduce costs and to improve production processes. It is also desired to improve the crosslinkability and mechanical properties while maintaining the advantages inherent in EMA foams.

The present invention comprises (1) ethylene acrylate copolymers and soft ethylene polymers or (2) ethylene acrylate copolymers, acid copolymers, ionomers of acid copolymers or combinations thereof and optionally soft ethylene polymers Wherein the ethylene acrylate copolymer comprises repeating units derived from ethylene and one or more alkyl (meth) acrylates or a combination of two or more thereof; The acid copolymer comprises repeating units derived from ethylene and one or more (meth) acrylic acids; Soft ethylene polymers include compositions that can be crosslinked to produce foam compositions comprising copolymers of ethylene and α-olefins, copolymers of ethylene and vinyl acetate, or combinations thereof.

The present invention also provides a crosslinked polymer foam comprising: (a) about 50 to about 95 weight percent, about 70 to about 90 weight percent or about 60 to about 80 weight percent ethylene acrylate copolymer, ( b) about 5 to about 50 weight percent or about 10 to about 30 weight percent acid copolymer or ionomer, and (c) about 0 to about 40 weight percent or about 5 to about 40 weight percent of a soft ethylene polymer, all of which are based on the combined weight of (a) + (b) + (c)).

The invention further provides midsoles or insoles of foam articles and footwear made from the foam compositions disclosed herein.

"Copolymer" means a polymer comprising repeating units derived from two or more monomers or comonomers and thus comprising terpolymers or quaternary copolymers.

The ethylene acrylate copolymer may comprise repeating units derived from ethylene and esters of unsaturated carboxylic acids, such as (meth) acrylates or C ₁ to C ₈ alkyl (meth) acrylates, or a combination of two or more thereof. . "(Meth) acrylate" refers to acrylate, alkyl acrylate, methacrylate or a combination of two or more thereof.

Examples of alkyl acrylates include methyl acrylate, ethyl acrylate and butyl acrylate. For example, "ethylene / methyl acrylate (E / MA)" means a copolymer of ethylene and methyl acrylate (MA); "Ethylene / ethyl acrylate (E / EA)" means a copolymer of ethylene and ethyl acrylate (EA); "Ethylene / butyl acrylate (E / BA)" means a copolymer of ethylene and butyl acrylate (BA); includes both n-butyl acrylate and iso-butyl acrylate; Combinations of two or more of these.

Copolymers of ethylene and acrylates are known. "Ethylene acrylate copolymer" may also refer to ethylene-acrylic acid ester copolymer. They can be produced in two high pressure free radical processes: tubular processes or autoclave processes. The difference between the ethylene acrylate copolymers prepared by the two processes is described, for example, in "High flexibility EMA made from high pressure tubular process." Annual Technical Conference-Society of Plastics Engineers (2002), 60th (Vol. 2), 1832-1836. In the present invention, ethylene acrylate copolymers prepared by the tubular process are preferred.

Alkyl acrylate comonomers incorporated into the ethylene acrylate copolymer may vary in content from 0.01 or 5 to up to 40 weight percent or more, such as 5 to 30, or 10 to 25 weight percent of the total copolymer. .

Ethylene acrylate copolymers may also include other comonomers such as carbon monoxide, glycidyl acrylate, glycidyl methacrylate and glycidyl vinyl ether or combinations of two or more thereof.

The ethylene acrylate copolymer may contain about 15 to about 40, or about 18 to about 35 weight percent of acrylate comonomer. Increasing the acrylate comonomer may improve the properties of the elastomer and increase the cohesiveness of the copolymer. The ethylene acrylate copolymer may have a melt index (MI) of about 0.1 to about 100, or about 0.5 to about 20 g / 10 minutes, as measured by ASTM D-1238 at E conditions (190 ° C., 2160 g). have.

Acid copolymers include repeating units derived from unsaturated carboxylic acids such as ethylene and (meth) acrylic acid, maleic acid, fumaric acid, maleic anhydride, fumaric anhydride, maleic monoester, fumaric acid monoester or a combination of two or more thereof can do. "(Meth) acrylic" refers to acrylic acid, methacrylic acid or combinations thereof. For example, "ethylene / methacrylic acid (E / MAA)" means a copolymer of ethylene (E) and methacrylic acid (MAA); "Ethylene / acrylic acid (E / AA)" means a copolymer of ethylene and acrylic acid (AA). Also included are examples of two or more comonomers. For example, "ethylene / isobutyl acrylate methacrylic acid (E / iBA / MAA)" is a terpolymer of ethylene (E), iso-butyl acrylate (iBA) and methacrylic acid (MAA). The acid copolymer may comprise from about 1 to about 10 mole percent repeat units derived from anhydrides or monoesters of acids or diacids.

The (meth) acrylic acid comonomer incorporated into the ethylene acid copolymer may vary in content from 0.01 or 5 to up to 30 weight percent or more, for example 5 to 25 or 10 to 25 weight percent, of the total copolymer. The acid copolymer may also contain up to 25% by weight of alkyl acrylates having alkyl groups with C ₁ -C ₈ alkyl acrylates.

Ethylene acid copolymers and methods for their preparation are known in the art as disclosed in US Pat. Nos. 3,264,272, 3,404,134, 3,355,319 and 4,321,337. Commercial acid copolymers suitable for use in the present invention include E. l. Du Pont de Nemours and Company (Dupont), Nucrel®, Wilmington, Delaware. Can be obtained from a variety of sources.

The ethylene acid copolymer can be a direct copolymer or a graft copolymer. 'Direct copolymer' means a copolymer made by polymerizing monomers together at the same time, and is distinguished from a graft copolymer in which monomers are polymerized on existing polymer chains. When a direct or graft acid copolymer contains from about 0.0001 to about 90 percent neutralized with metal ions and ionized carboxylic acid groups, it is termed an ionic copolymer or "ionomer", which is the solid state property of the crosslinked polymer. And melt-making of uncrosslinked thermoplastic polymers. Commercial ionomers include DuPont's Surlyn ^® ionomer.

The acid copolymer or ionomer is preferably in the range of about 5% to about 50% by weight, more preferably in the range of about 10% to about 30% by weight, most preferably in the range of about 8% to about 15% by weight. Exists in the amount of. The acid copolymer preferably contains about 4 to about 25 weight percent acid, more preferably about 8 to about 15 weight percent acid. The acid copolymer may have a melt index of 0.1 to 500, preferably 1 to 100, most preferably 1 to 30 g / 10 minutes.

The ionomer may have a melt index of about 0.1 to 100 or about 0.5 to 20 g / 10 minutes, and may be derived from an acid copolymer having about 4 to about 25 or about 8 to about 15 weight percent acid, and about It may have a degree of neutralization in the range of 20 to 70% by weight.

Soft ethylene polymers include copolymers of ethylene and α-olefins, copolymers of ethylene and vinyl acetate, or combinations thereof. Soft ethylene polymers can be prepared by any process known in the art, including using Ziegler-Natta catalysts, metallocene catalysts, and other catalysts useful in "low pressure" polymerization processes. EVA copolymers can be prepared, for example, by a "high pressure" polymerization process using free radical initiators. Since these processes are known, the disclosure of these processes is omitted here for brevity.

Soft ethylene polymers include linear low-density polyethylene (LLDPE), metallocene-catalyzed polyethylene (MPE), EVA copolymers, or a combination of two or more thereof. The MPE may have a density of less than about 0.89 and a melt index (MI) of about 0.1 to 100 or about 0.5 to 30 g / 10 minutes as measured by ASTM D-1238 at E conditions (190 ° C., 2160 g). It can have The EVA may comprise at least about 15 wt%, or about 15 to about 35 wt%, or about 18 to 30 wt% repeat units derived from vinyl acetate. Ethylene soft polymers have a melt index of about 0.1 to 100 or about 0.5 to about 20 (for EVA, about 0.5 to 30) g / 10 minutes as measured by ASTM D-1238 at E conditions (190 ° C., 2160 g). May have (MI). EVA can use the thing of DuPont.

MPE also refers to metallocene polyethylene copolymers, which are copolymers of ethylene and α-olefin monomers with metallocene catalysts. MPE technology can be used to produce low density MPE with high flexibility and low crystallinity. MPE technology is disclosed, for example, in US Pat. Nos. 5,272,236, 5,278,272, 5,507,475, 5,264,405, and 5,240,894. MPE copolymers are available from Dow Chemical Co. Affinity ^® , DuPont-Dow Engage ^® and Exxon Mobile Exact ^® And Plastomer ^® .

The composition may also be a crosslinked foam composition with the desired properties such as high elasticity, low permanent compression and most important foam ductility. For example, foams derived from ethylene / methyl acrylate copolymers (E / MA) with high MA content are generally ductile, have a low density, and may have high elasticity. These properties are desirable for foam footwear articles, especially midsoles and insoles. Mechanical properties of EMA foams, such as split tear resistance and tensile strength, may be undesirable to maintain long durability. As the density of the foam decreases, the mechanical properties of the E / MA foam may deteriorate. Blending the E / MA and ethylene acid copolymers increases the mechanical properties of the E / MA foams to produce E / MA foams useful for midsole foam articles.

The foam composition comprises about 95 to about 40 weight percent, about 90 to about 50 weight percent or about 80 to about 60 ethylene acrylate copolymers such as ethylene-methyl acrylate, ethylene-butyl acrylate or ethylene-ethyl acrylate. It may include weight percent.

The soft ethylene polymer may be present in the range of about 0 to about 40 weight percent or about 5 to about 30 weight percent or about 10 to 30 weight percent.

The composition may additionally comprise a polymer other than those disclosed above, including LDPE, LLDPE, or a combination thereof, in an amount ranging from about 0.01 to about 15 or 0.5% to about 10% by weight of the composition.

The composition also includes a free radical initiator or a crosslinking agent comprising an organic peroxide (ie, about 0.2 to about 1.5 parts by weight peroxide per 100 parts by weight of the composition) such as dialkyl organic peroxide in the range of about 0.2 to about 1.5%. can do. Examples of organic peroxides include 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, t-butyl-cumyl peroxide, dicumyl-peroxide, 2,5-dimethyl-2 , 5-di (tert-butyl-peroxyl) hexane, 1,3-bis (tert-butyl-peroxy-isopropyl) benzene or a combination of two or more thereof.

The composition also includes from about 0.001 to about 1 weight percent of a co-curing agent comprising trimethyl propane triacrylate (and similar compounds), N, Nm-phenylenedimalimide, triallyl cyanuate or a combination of two or more thereof can do.

The foam composition may also include about 0.001 or about 0.2 to about 10 weight percent of the blowing agent in the composition. The blowing agent may be a chemical blowing agent or a physical blowing agent. Physical blowing agents are carbon halides, volatile organic compounds or non-flammable inert atmospheric gases and the like. Chemical blowing agents include azodicarbonamide (ADCA), dinitroso-pentamethylene-tetramine (DPT), P-toluene sulfonyl hydrazide and p.p'-oxybis (benzenesulfonyl hydrazide). In order to control the expansion-decomposition temperature and the foaming process, the blowing agent may also be a mixture of several blowing agents or a mixture of blowing agents and foaming aids. For example, vinyl of AK-2 (manufactured by Eiwa Kasei Chemical Co., Japan) is a mixture of ADCA and DPT. Uniroyal Chemical Celogen 765 is a modified ADCA.

The composition may also include from about 1 to about 10 weight percent or from about 2 to 6 weight percent of active agent (for foaming agent) based on the composition to lower the decomposition temperature / profile of the blowing agent. The active agent of the blowing agent may be one or more metal oxides, metal salts or organometallic complexes. ZnO, Zn stearate, MgO or a combination of two or more thereof may be exemplified.

Other additives include those typically used in similar crosslinked polymer compositions, including pigments (TiO ₂ and other commercially available colored pigments), adhesion promoters (to enhance the properties of the expanded blowing agent adhere to other materials), fillers ( For example, calcium carbonate, barium sulfate and / or silicon oxide, nucleating agent (pure or concentrated form, for example CaCO ₃ and / or SiO ₂ , rubber (natural rubber, SBR, polybutadiene and / or ethylene) To enhance rubber-like elasticity such as propylene terpolymers, stabilizers (eg, antioxidants, ultraviolet absorbers and / or flame retardants) and processing aids (eg, Octene Co., Taiwan). Octene (Octene) R-130) may be prepared.

Foam compositions can be prepared by a variety of methods such as compression molding, injection molding, and mixing methods of extrusion and molding. The method may comprise mixing the polymers with the crosslinking agent to produce a homogeneous compound and heating the melt together with the blowing agent and other typical additives. The components can be mixed and blended by any means known in the art, such as Banbury mixers, intensive mixers, two-roll mills and extruders. Time, temperature and shear rate can be adjusted to ensure optimal dispersion without crosslinking or foaming prematurely. The application of high temperatures during mixing decomposes the peroxide and blowing agent, leading to premature crosslinking and foaming. Suitable temperatures may be desirable for good mixing of the polymers (eg, E / MA and E / MAA) and for dispersing the other components. E / MA and E / MAA may form a uniform blend when blended at a temperature of about 60 to about 150 ° C, about 80 to about 150 ° C or about 70 to about 120 ° C or about 80 to about 130 ° C. The upper limit of temperature for safe operation may vary depending on the decomposition initiation temperature of the peroxide and blowing agent used. The polymers may be melt-blended before blending with the other ingredients.

Optionally, polymers such as E / MA and E / MAA can be melt-blended at temperatures of about 250 ° C. or less inside the extruder to potentially mix well. The resulting mixture can then be combined with the other ingredients disclosed above.

After the mixing has taken place, shaping can be performed. Sheeting rolls or calender rolls are often used to make sheets of suitable dimensions for foaming. An extruder can be used to mold the composition into pellets.

Foaming can be performed in a compression mold at the temperature and time at which decomposition of the peroxide and blowing agent is completed. Pressure, molding temperature and heating time can be adjusted. Foaming can be done in an injection molding apparatus using foam compositions in pellet form. The resulting foam can be further molded to the dimensions of the final product using any means known in the art, such as thermoforming and compression molding.

The resulting polymer foam compositions are substantially closed bubbles and can be usefully used in a variety of articles such as, for example, footwear articles including midsoles or insoles.

The invention may be illustrated by the following examples, which do not limit the scope of the invention.

Test Methods

Crosslinking properties were measured with an MDR-2000 rheometer (A-Technology Co., Ohio) according to ASTM-2084 under conditions similar to foaming conditions. Maximum torques are reported in Table 1.

The bounce elasticity test of the foam was measured according to ASTM D 3574. The hardness of the foams was measured with a C type (spring type) hardness tester of ASKER, Japan, in accordance with ASTM D2240. Permanent compression rate was measured according to ASTM D 3754 at 50 ° C./6 hours. Split-tear was measured according to ASTM D 3574. The compressive strength test was performed with an Instron Universal tester equipped with a compression cage that deforms the foam sample at a uniform rate of 0.05 inches / minute. The stress required to produce a compressive strain of up to 50% was measured. Compressive stress was measured as force per unit area based on the cross section of the original foam.

Preparation of the sample :

The weight was measured using a Mettler PC 2000 balance before mixing the polymer and the chemical. E / MA and E / MAA were charged to a half-barrier mixer (Bolling internal mixer). The capacity of the mixer was 1100 cc. The resins were refluxed at a temperature of 150 ° F-200 ° F. After 1-2 minutes remaining components (except peroxide and blowing agent) were incorporated for 4-5 minutes. Then, peroxides, blowing agents and other ingredients were added. Maintain at 200 ° F. and continue mixing for 4-5 minutes. The compound was taken out and transferred to a 6 inch x 13 inch bowling OX 2-roll mill. The mill was oil heated and set to 150 ° F. The batch size of the mill was about 500-1200 g. The maximum speed was 35 feet per minute. Roll spacing was adjusted to produce sheets for sample cutting (150-300 mil).

Samples were cut with a Hudson Hydraulic Clicker using a 3 inch by 3 inch die and weighed 90 g. The foaming process consisted of placing 90 g of sample in a 3 inch by 3 inch beveled mold having a total dimension of 6 x 6 x 1/2 inch. The sample was placed between two 9 inch by 10 inch by 1/4 inch aluminum plates. Plates and samples were placed in an automatic PHI press. Samples are generally placed in the press under a pressure of about 3300 lbs at a temperature of about 155 ° C.-185 ° C. for 10-30 minutes. When the mold opened at the end of the molding cycle, the foam formed immediately.

Table 1 shows that the foams of ethylene acrylate copolymers (Comparative Examples A, B, and C) exhibited ductility (results of hardness measurement of foams) and excellent elasticity, which provide a comfortable fit with desirable performance, but with low mechanical properties (split- Tear strength and compressive strength, eg, Comparative Examples B and C), showing poor curing behavior (as reflected in the maximum torque value, eg, Comparative Example A).

Comparative Example A of 0.8 pph peroxide has a low degree of curing, as indicated by the low torque value. Comparative Example B of 1.2 pph peroxide showed a higher torque value and the permanent compression rate was also improved. However, the split-tear characteristics deteriorated. Comparative Example C of 1 pph peroxide with the addition of the co-curing triallyl cyanuate also improved the degree of cure and permanent compression. Again, the split-tear characteristics worsened. These results indicate that E / MA foams cannot achieve balanced mechanical properties.

Table 1 also shows that foams made from blends of E / MA and MPE (Examples 1, 2, 3 and 4) have improved hardening degree (shows crosslinking, see maximum torque values) and mechanical properties compared to the comparative example. Shows. Blend foams possessed high elasticity and high ductility that are characteristic of the original E / MA foams. For example, the foams of Examples 3 and 4 had high elasticity and good ductility (foam hardness value), low permanent compression and good split-tear strength. These results show that when the foam density is low, the split-tear strength, which is a measure of durability, has a consistently high value and can achieve desirable balanced properties for footwear articles.

¹ amount of peroxide used: Comparative Example A (0.8 pph, parts per 100 parts of composition); Comparative Example B (1.2 pph); Comparative Example C (1 pph); Example 1 (0.8 pph); Example 2 (0.8 pph); Example 3 (1 pph); Example 4 (1.2 pph).

Composition of the Example:

All examples are E / MA (ethylene / methyl acrylate copolymer, DuPont containing 24 wt.% MA with MI value of 2.0) and Cellogen 765 (Uniroyal Co.) as blowing agent. Was used. TAC stands for triallyl cyanuate.

Comparative Example A : E / MA, 832 g; DCP, 6.7 g; Blowing agent, 30 g; Zn stearate, 8.0 g; ZnO, 8.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Comparative Example B : E / MA, 832 g; DCP, 10.0 g; Blowing agent, 30 g; Zn stearate, 4.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Comparative Example C : E / MA, 832 g; DCP, 8.5 g; TAC, 4.5 g; Blowing agent, 25 g; Zn stearate, 4.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Example 1 : E / MA, 550 g; MPE (density = 0.87 g / cc; Ml = 1.0, DuPont Dow Elastomer), 276 g; DCP, 6.7 g; Blowing agent, 30 g; Zn stearate, 8.0 g; ZnO, 8.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Example 2 : E / MA, 450 g; MPE, 382 g; DCP, 6.7 g; Blowing agent, 30 g; Zn stearate, 8.0 g; ZnO, 8.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Example 3 : E / MA, 500 g; MPE, 333 g; DCP, 8.3 g; Blowing agent, 30 g; Zn stearate, 8.0 g; ZnO, 8.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Example 4: DCP, 10 g; Other compositions are the same as in Example 3.

Table 2 shows that the foams (Comparative Examples D, E and F) of ethylene-methyl acrylate copolymers exhibited ductility and low mechanical properties. All the comparative examples showed low split-tear strength and compressive strength. Compressive strength determines the foam strength at a given density.

Comparative Examples E and F, which contain higher peroxide content (Comparative Example F additionally includes co-curing agents) show improved permanent compression, but have worse split-tear characteristics.

EMA foams modified with acid copolymer / ionomer trace components showed higher tear strength and compressive strength. Example 7 containing a soft E / nBA / MAA terpolymer further improved tear strength. All foams are ductile, which is a useful property for EMA foams. Example 8, containing both acid copolymer and MPE, appeared to have high elasticity and to achieve good ductility and mechanical properties, thereby achieving balanced properties. The above examples show that the desired balanced properties are obtained for an article of footwear.

¹ peroxide used: Comparative Example A (0.8 pph, parts per 100 parts of composition); All other comparative examples and examples were each 1 pph.

Composition of the Example:

Comparative Example D : E / MA, 832 g; DCP, 6.7 g; Blowing agent, 30 g; Zn stearate, 8.0 g; ZnO, 8.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Comparative Example E : E / MA, 832 g; DCP, 8.5 g; Blowing agent, 30 g; Zn stearate, 4.0 g; CaCO ₃ , 25 g.

Comparative Example F : E / MA, 832 g; DCP, 8.5 g; TAC, 4.5 g; Blowing agent, 25 g; Zn stearate, 4.0 g; Stearic acid, 4.0 g; CaCO ₃ , 25 g.

Example 5 : E / MA, 707.3 g; E / MAA (ethylene / methacrylic acid copolymer, MI of 3.0 and containing 9% by weight of methacrylic acid, DuPont), 124.3 g; DCP, 8.5 g; Blowing agent, 30 g; Zn stearate, 4.0 g; CaCO ₃ , 25 g.

Example 6 : E / MA, 707.3 g; E / MAA (as in Example 1), 124.3 g; DCP, 8.5 g; 4.5 g TAC; Blowing agent, 30 g; Zn stearate, 4.0 g; CaCO ₃ , 25 g.

Example 7 : E / MA, 707.3 g; E / nBA / MAA (terpolymer of ethylene, n-butyl acrylate and methacrylic acid, DuPont, with a MI of 30 and 23% by weight of n-butyl acrylate and 9% by weight of methacrylic acid), 124.3 g; DCP, 8.5 g; Blowing agent, 30 g; Zn stearate, 4.0 g; CaCO ₃ , 25 g.

Example 8 : E / MA, 442 g; MPE (copolymer of ethylene and 1-octene with a MI of 1.0 and a density of 0.87 g / cc, DuPont Dow Elastomer), 265 g; E / MAA, 124.3 g; DCP, 8.5 g; Blowing agent, 30 g; Zn stearate, 6 g; Stearic acid, 9.6 g.

Claims (10)

(1) ethylene acrylate copolymers and soft ethylene polymers; Or (2) ethylene acrylate copolymers, acid copolymers, ionomers of acid copolymers or combinations thereof and optionally soft ethylene polymers, The ethylene acrylate copolymer comprises repeating units derived from ethylene and one or more alkyl acrylates; The acid copolymer comprises repeating units derived from ethylene and (meth) acrylic acid, maleic acid, fumaric acid, maleic anhydride, fumaric anhydride, maleic monoester, fumaric acid monoester or a combination of two or more thereof; The soft ethylene polymer comprises a copolymer of ethylene and an -olefin, a copolymer of ethylene and vinyl acetate, or a combination thereof. The process of claim 1 comprising or made from an ethylene acrylate copolymer and a soft ethylene polymer; Preferably, about 40 to about 95 weight percent of the ethylene acrylate copolymer and about 5 to about 60 weight percent of the soft ethylene polymer, based on the total weight of the composition; The ethylene acrylate copolymer preferably comprises repeating units derived from ethylene and methyl acrylate. The composition of claim 2 wherein the ethylene acrylate copolymer comprises ethylene and about 15 to about 40 weight percent methyl acrylate. The method of claim 1, wherein the ethylene acrylate copolymer; Acid copolymers, ionomers of acid copolymers, or combinations thereof; And optionally comprise or are made from a soft ethylene polymer; The acid copolymer comprises repeating units derived from ethylene and methacrylic acid, acrylic acid or combinations thereof. The method of claim 4, wherein the ethylene acrylate copolymer; Acid copolymers, ionomers of acid copolymers, or combinations thereof; And compositions comprising or prepared from soft ethylene polymers. 6. The method of claim 4 or 5, comprising about 50 to about 95 weight percent or about 70 to about 90 weight percent ethylene acrylate copolymer; About 5 to about 50 weight percent or about 10 to about 30 weight percent of an acid copolymer or combination of ionomers; And from 0 to about 40 weight percent of a soft ethylene polymer. 7. The flexible ethylene polymer according to claim 1, 2, 3, 4, 5, or 6, wherein the soft ethylene polymer is linear low density polyethylene, metallocene-catalyzed polyethylene, polyethylene vinyl acetate, or A combination of two or more of these; The metallocene catalyst-made polyethylene has a density of less than about 0.89 g / cc, and the polyethylene vinyl acetate comprises at least about 15% by weight of vinyl acetate repeat units; The soft ethylene polymer is preferably a metallocene catalyst-made polyethylene. 8. The method of claim 1, 2, 3, 4, 5, 6, and 7, further comprising from about 0.2 to about 1.5 weight percent of crosslinkers, from about 0.5 to about 10 weight percent blowing agents, about 0.1 to about 10 weight percent active agents, and optionally about 0.1 to about 1 weight percent co-curing agents; Optionally further comprising low-density polyethylene and linear low-density polyethylene. The composition of claim 8, wherein the bounce elasticity is at least about 50% measured by ASTM D 3574. Claims 1, 2, 3, 4, 5, 6, 7, 8, comprising foams, midsoles of footwear, insoles of footwear, or combinations of two or more thereof. And an article comprising or prepared from the composition of claim 9.