A plasticizer may be suitable for resins and contain an amorphous propylenic polymer having a weight-average molecular weight (Mw), measured according to a GPC method, in a range of from 5,000 to 30,000 and having a molecular weight distribution (Mw/Mn) of 3.0 or less. The amorphous propylenic polymer may be a propylene homopolymer

A recyclable crosslinked polymeric foam includes a reaction product of 0.1 to 10 parts by weight of a crosslinking agent and 0.1 to 5 parts by weight of a radical initiator, based on 100 parts by weight of a polymeric material. The crosslinking agent is represented by the following formula:

##STR00001##

wherein R is an alkylene group having 2 to 10 carbon atoms, an arylene group having 6 to 18 carbon atoms, or a cycloalkylene group having 6 to 18 carbon atoms.

A recyclable crosslinked polymeric foam includes a reaction product of 0.1 to 10 parts by weight of a crosslinking agent and 0.1 to 5 parts by weight of a radical initiator, based on 100 parts by weight of a polymeric material. The crosslinking agent is represented by the following formula:

##STR00001##

wherein R is an alkylene group having 2 to 10 carbon atoms, an arylene group having 6 to 18 carbon atoms, or a cycloalkylene group having 6 to 18 carbon atoms.

A molded product of a polypropylene-based resin composition, without containing an inorganic filler, and obtained by a polypropylene-based resin composition that does not contain an inorganic filler and includes: 60 to 90 parts by mass of a polypropylene-based resin (A) including 30 to 80 parts of a propylene-based polymer (a-1) having an MFR of 120 to 250 g/10 min and having 98 to 100 mol % of a propylene constituent unit, and 0 to 30 parts of a propylene/ethylene copolymer (a-2) having an intrinsic viscosity [η] of 4 to 7 dl/g and having 30 to 60 mol % of an ethylene constituent unit; 10 to 40 parts of an ethylene/α-olefin copolymer (B) having an MFR of 0.1 to 7 g/10 min and having an ethylene content of 65 to 90 mol %; 0.2 to 1 part of a fatty acid amide (C); and 0.1 to 1 part of a surfactant (D).

A molded product of a polypropylene-based resin composition, without containing an inorganic filler, and obtained by a polypropylene-based resin composition that does not contain an inorganic filler and includes: 60 to 90 parts by mass of a polypropylene-based resin (A) including 30 to 80 parts of a propylene-based polymer (a-1) having an MFR of 120 to 250 g/10 min and having 98 to 100 mol % of a propylene constituent unit, and 0 to 30 parts of a propylene/ethylene copolymer (a-2) having an intrinsic viscosity [η] of 4 to 7 dl/g and having 30 to 60 mol % of an ethylene constituent unit; 10 to 40 parts of an ethylene/α-olefin copolymer (B) having an MFR of 0.1 to 7 g/10 min and having an ethylene content of 65 to 90 mol %; 0.2 to 1 part of a fatty acid amide (C); and 0.1 to 1 part of a surfactant (D).

A thermoplastic elastomer compound includes polyolefin elastomer, high softening point tackifier, and, optionally, styrenic block copolymer. When styrenic block copolymer is present, the weight ratio of polyolefin elastomer to styrenic block copolymer is no less than about 1:1. The polyolefin elastomer has a POE Tan Delta Peak Temperature, the styrenic block copolymer has a SBC Tan Delta Peak Temperature, and the thermoplastic elastomer compound has a Compound Tan Delta Peak Temperature. The Compound Tan Delta Peak Temperature is greater than the POE Tan Delta Peak Temperature. When styrenic block copolymer is present, Compound Tan Delta Peak Temperature is also greater than the SBC Tan Delta Peak Temperature. The thermoplastic elastomer compound exhibits useful damping properties at or above room temperature and can be formed into plastic articles, including foamed plastic articles and/or crosslinked plastic articles, which can be useful for a variety of damping applications.

A thermoplastic elastomer compound includes polyolefin elastomer, high softening point tackifier, and, optionally, styrenic block copolymer. When styrenic block copolymer is present, the weight ratio of polyolefin elastomer to styrenic block copolymer is no less than about 1:1. The polyolefin elastomer has a POE Tan Delta Peak Temperature, the styrenic block copolymer has a SBC Tan Delta Peak Temperature, and the thermoplastic elastomer compound has a Compound Tan Delta Peak Temperature. The Compound Tan Delta Peak Temperature is greater than the POE Tan Delta Peak Temperature. When styrenic block copolymer is present, Compound Tan Delta Peak Temperature is also greater than the SBC Tan Delta Peak Temperature. The thermoplastic elastomer compound exhibits useful damping properties at or above room temperature and can be formed into plastic articles, including foamed plastic articles and/or crosslinked plastic articles, which can be useful for a variety of damping applications.

A crosslinked rubber composition contains a rubber component and para-aramid short fibers having a filament fineness of 2.5 dtex or more and dispersed in the rubber component.

A crosslinked rubber composition contains a rubber component and para-aramid short fibers having a filament fineness of 2.5 dtex or more and dispersed in the rubber component.

A crosslinked rubber composition contains a rubber component and para-aramid short fibers having a filament fineness of 2.5 dtex or more and dispersed in the rubber component.