The present invention provides a crosslinked propylene-based elastomer having an isotactic propylene triad tacticity of from 65 to 95%, a melting point by DSC equal to or less than 110° C., a heat of fusion of from 5 J/g to 50 J/g, and a haze % per 100 mil thickness of 95 or less, and comprising at least 75 wt % propylene-derived units, at least 5 wt % ethylene-derived units, and optionally 10 wt % or less of diene-derived units. In an embodiment, the present invention is a blend of a continuous phase of the crosslinked propylene-based elastomer and a dispersed phase of a crystalline polymeric compound. The present invention also provides elastomeric compositions comprising a crosslinked propylene-based elastomer as described herein and 100 parts by weight or less of a pigment per 100 parts of polymer. The present invention also provides films, fibers, nonwovens, molded objects, and extruded forms which include any of the inventive compositions described herein.

Transparent and translucent crosslinked propylene-based elastomers, and their production and use

A thermoplastic olefin comprising an alloy of an olefin copolymer elastomer and a propylene/comonomer random copolymer is provided. The comonomer is selected from one or more of ethylene and C4 to C10 alpha-olefins. Polypropylene is an optional component of the alloy. The alloy may be produced by melt blending, reactor blending or a combination thereof, of the various components.

Thermoplastic olefin alloys and method for producing the same

The present invention is directed generally to the use of propylene-based elastomers in articles. The propylene-based elastomers have isotactic polypropylene crystallinity, a melting point by DSC of 110° C. or less, a heat of fusion of from 5 to 50 J/g, and comprise at least 75 wt % propylene-derived units, at least 6 wt % ethylene-derived units, and optionally diene-derived units. The present invention is also directed to processes for making articles comprising propylene-based elastomers.

Articles comprising propylene-based elastomers

A method for producing a rubber composition crosslinked to a crosslinking degree of 50% or higher by mixing a crosslinkable rubber (A) and a thermoplastic resin (B) and crosslinking the mixture with a crosslinking agent (C), wherein the crosslinking agent (C) is divided and added in parts to sequentially carry out the crosslinking in which the crosslinking is carried out to a crosslinking degree of 5-45% by the first addition of the crosslinking agent (C) and furthermore the crosslinking is carried out to a crosslinking degree of 50% or higher by further addition of the crosslinking agent (C).

Method for producing rubber composition

Disclosed herein is a preparation process for polypropylene-base resin compositions, which process comprises heating at a temperature of 170°-280° C. a mixture containing a crystalline ethylenepropylene block copolymer having a specific composition, an ethylene-propylene copolymer rubber having a specific composition and viscosity, an inorganic filler having a specific particle size, and an organic peroxide, all in specified amounts. The thus-obtained polypropylene-base resin compositions are suitable for use in the production of large moldings such as automobile bumpers, fenders and body sidemembers because of their excellent low-temperature impact resistance, high molding fluidity, good paintability and high stiffness as well as their low preparation cost.

Preparation process for polypropylene-base resin compositions

PURPOSE: To prepare a thermoplastic elastomer with good elastic properties by the reaction of a curing agent with an intimate blend of a monoolefin copolymer rubber which was previously blended with a crystalline resin. COPYRIGHT: (C)1977,JPO&Japio

Hideo Nakanishi

Papers

Preparation of thermoplastic elastomer

Manufacture of thermoplastic elastomer