An expanded bead having a through hole and including a foamed core layer which defines the through hole therein and which is constituted of a resin composition containing two kinds of polypropylene-based resins having different melting points, and a cover layer covering the foamed core layer and constituted of a polyolefin-based resin. The expanded bead gives a DSC curve in which an endothermic peak intrinsic to the resin composition and another endothermic peak on a higher temperature side thereof appear in a specific heat of fusion ratio. Molded articles include a multiplicity of the expanded beads.

A thermoplastic polyolefin composition which is capable of being shaped and repeatedly recycled, comprises propylene-based polymers, said composition being modified with 0.01-5 wt % of organic oligomeric silanes selected from partially hydrolyzed alkoxy substituted vinyl, allyl or methacryl silanes, and blends thereof, and 0.0005-0.5 wt % of a compound capable of generating free radicals.

An injection-molded article for medical use obtained by using a medical propylene-ethylene-based resin composition including 88 to 95 parts by mass of a propylene-ethylene resin composition (A) that contains more than 90% and equal to less than 97% by mass of a propylene-ethylene copolymer (a) having an ethylene content of 1 to 5% by mass, and a melt flow rate conforming to JIS K7210 (230° C., 2.16 kg load) being 10 to 100 g/10-min, and equal to more than 3% and less than 10% by mass of a propylene-ethylene copolymer (b) having an ethylene content of 15 to 22% by mass and an MFR of 1 to 50 g/10-min, 5 to 12 parts by mass of an elastomer (B) that is an ethylene-α-olefin random copolymer which is an ethylene-α-olefin random copolymer having a density of 0.880 to 0.920 g/cm.sup.3; and 0.01 to 0.20 parts by mass of a weather-resistant stabilizer.

Expanded polypropylene resin particles include a polypropylene resin as a base material resin, wherein the polypropylene resin has a flexural modulus of 750 MPa to 1100 MPa. The flexural modulus and a melting point of the expanded polypropylene resin particles satisfy Expression (1): [Flexural modulus (MPa)]<31.19×[Melting point (° C.)]−3500, wherein the melting point of the expanded polypropylene resin particles is a melting point of 141.5° C. to 150.0° C. in a second differential scanning calorimetry (DSC) curve of a second temperature increase, the second DSC curve being obtained when the expanded polypropylene resin particles are heated from 40° C. to 220° C. at a temperature increase rate of 10° C./min in a first temperature increase, then cooled from 220° C. to 40° C. at a temperature decrease rate of 10° C./min, and heated again from 40° C. to 220° C. at a temperature increase rate of 10° C./min in the second temperature increase.

A roofing membrane and a method of making the same is provided. The roofing membrane includes a top layer having a flame retardant and a first silane-crosslinked polyolefin elastomer with a density less than 0.90 g/cm.sup.3; a scrim layer; and a bottom layer having a flame retardant and a second silane-crosslinked polyolefin elastomer with a density less than 0.90 g/cm.sup.3. The top and bottom layers of the roofing membrane both exhibit a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70° C.).

Disclosed is an elastomer composition comprising polyolefin elastomer material which exhibits improved hysteresis properties, said elastomer composition having the following properties: (1) an average integrated enthalpy sum of no greater than 17 J/g according to the Thermal Analysis Method defined herein; (2) an average integrated enthalpy ratio of from 0.6 to 300 according to the Thermal Analysis Method defined herein; (3) an unload stress at 75% strain of above 0.8 MPa according to the Hysteresis Test defined herein; and (4) a load stress/unload stress ratio at 75% strain of 1 to 2.6 according to the Hysteresis Test defined herein.

Microporous polymer films and methods of making same are disclosed. The microporous polymer film comprises: (a) 50 to 95 weight percent of polypropylene copolymer comprising (i) polypropylene homopolymer chain segments in total amount of from 50-82 wt. %, and (ii) ethylene-containing copolymer chain segments in total amount of from 18-50 wt. %; wherein at least a portion of the ethylene-containing copolymer chain segments comprise polymerized units of ethylene in an amount of at least 45 wt. % of the ethylene-containing copolymer chain segments; and (b) 5 to 50 weight percent of ethylene-propylene elastomer, wherein at least 45 weight percent of the polymerized units in the ethylene-propylene elastomer are units of ethylene.

Heterophasic polypropylene composition with an advantageous, respectively stiffness/impact balance and its use.

The instant invention provides a polymeric blend composition, injection molded articles, films and sheets made therefrom. The polymeric blend composition according to the present invention comprises: (a) a first component selected from the group consisting of an ethylene/alpha-olefin copolymer and a propylene/ethylene copolymer; wherein said ethylene/alpha-olefin co-polymer has density in the range of from 0.857 to 0.902 g/cm.sup.3, a melt index (I.sub.2) in the range of from 0.5 to 30 g/10 minutes, a DCS melting point temperature (second heat) in the range of from 40 to 99° C., a heat of fusion in the range of from 18 to 108 Jg.sup.−1, and a crystallinity in the range of from 6 to 37 weight percent; and wherein propylene/ethylene copolymer has a melt flow rate in the range of from 1 to 30 g/10 minutes, a DCS melting point temperature (second heat) in the range of from 55 to 85° C., a heat of fusion in the range of from 10 to 40 Jg.sup.−1, and a crystallinity in the range of from 6 to 21 weight percent; and (b) less than 40 percent by weight of a second component comprising an ethylene vinyl acetate copolymer comprising from 9 to 40 percent by weight of units derived from vinyl acetate, and wherein said ethylene vinyl acetate copolymer has a melt index (I.sub.2) in the range of from 0.2 to 20 g/10 minutes; wherein Δ.sub.n is less than 0.003, and wherein Δ.sub.n is the absolute value of the difference between the refractive index of (a) and (b); and wherein dielectric loss factor of the polymeric blend composition is, equal to, or greater than, 0.024, for example in the range of greater than 0.024 to 0.15.

Provided herein is a polymer comprising from about 65 wt % to about 90 wt % based on the total weight of the blend of an ethylene α-olefin elastomer having either no crystallinity or crystallinity derived from ethylene, having greater than about 75 wt % units derived from ethylene; and from about 10 wt % to about 35 wt % based on the total weight of the blend of a propylene polymer having about 40 wt % or more units derived from propylene, including isotactically arranged propylene derived sequences; wherein the ethylene α-olefin elastomer and the propylene polymer are prepared in separate reactors arranged in parallel configuration.