Airplane tire tread (2), having an axial width L, comprises a middle part (3) having an axial width L.sub.C at least equal to 50% and at most equal to 80% of L and composed of a middle rubber composition, and two lateral parts (41, 42), positioned axially on either side of the middle part (3), each having an axial width (L.sub.S1, L.sub.S2) between 10% and 25% of L and each composed of a lateral rubber composition. The middle rubber composition comprises at least 50 phr of a first diene elastomer, a reinforcing filler and a crosslinking system, which first diene elastomer comprises ethylene units and diene units comprising a carbon-carbon double bond, which units are distributed randomly within the first diene elastomer, the ethylene units representing at least 50 mol % of all the monomer units of the first diene elastomer.

Airplane tire tread (2), having an axial width L, comprises a middle part (3) having an axial width L.sub.C at least equal to 50% and at most equal to 80% of L and composed of a middle rubber composition, and two lateral parts (41, 42), positioned axially on either side of the middle part (3), each having an axial width (L.sub.S1, L.sub.S2) between 10% and 25% of L and each composed of a lateral rubber composition. The middle rubber composition comprises at least 50 phr of a first diene elastomer, a reinforcing filler and a crosslinking system, which first diene elastomer comprises ethylene units and diene units comprising a carbon-carbon double bond, which units are distributed randomly within the first diene elastomer, the ethylene units representing at least 50 mol % of all the monomer units of the first diene elastomer.

[Problem] The purpose of the invention is to provide: a thermoplastic elastomer composition capable of providing molded articles that are lightweight, have better oil resistance than those provided by conventional cross-linked thermoplastic elastomers, and have hardness and mechanical properties such as tensile strength and tensile elongation that are equal to or superior to those provided by conventional cross-linked thermoplastic elastomers; and an ethylene/α-olefin/unconjugated polyene copolymer having little compression set at low temperature as well as flexibility and an excellent balance of rubber elasticity at low temperature and tensile strength at normal temperature. [Solution] Produced are: a thermoplastic elastomer composition obtained by dynamically crosslinking a mixture containing a crystalline olefin polymer (A), an ethylene/α-olefin (having 4-20 carbon atoms)/unconjugated polyene copolymer (1B) that satisfies specific requirements, and a phenol resin-based crosslinking agent (C); and an ethylene-α-olefin/unconjugated polyene copolymer (2B) that satisfies specific requirements.

[Problem] The purpose of the invention is to provide: a thermoplastic elastomer composition capable of providing molded articles that are lightweight, have better oil resistance than those provided by conventional cross-linked thermoplastic elastomers, and have hardness and mechanical properties such as tensile strength and tensile elongation that are equal to or superior to those provided by conventional cross-linked thermoplastic elastomers; and an ethylene/α-olefin/unconjugated polyene copolymer having little compression set at low temperature as well as flexibility and an excellent balance of rubber elasticity at low temperature and tensile strength at normal temperature. [Solution] Produced are: a thermoplastic elastomer composition obtained by dynamically crosslinking a mixture containing a crystalline olefin polymer (A), an ethylene/α-olefin (having 4-20 carbon atoms)/unconjugated polyene copolymer (1B) that satisfies specific requirements, and a phenol resin-based crosslinking agent (C); and an ethylene-α-olefin/unconjugated polyene copolymer (2B) that satisfies specific requirements.

A method of crosslinking a polyolefin resin with a silyl hydride crosslinking agent is disclosed. Crosslinkable compositions containing a polyolefin resin having about 0.9% to about 10% diene groups and a silyl hydride crosslinking agent are also disclosed.

A method of crosslinking a polyolefin resin with a silyl hydride crosslinking agent is disclosed. Crosslinkable compositions containing a polyolefin resin having about 0.9% to about 10% diene groups and a silyl hydride crosslinking agent are also disclosed.

A copolymer of ethylene and of isoprene, which comprises from 10 to 35 mol % of isoprene units, at least 70% of which are in the 3,4 configuration and a portion of which is in the 1,2 configuration is provided. A copolymer of this type with a reduced crystallinity is synthesized with a much higher productivity than its homologues of ethylene and of butadiene, and also confers improved curing properties on rubber compositions.

A copolymer of ethylene and of isoprene, which comprises from 10 to 35 mol % of isoprene units, at least 70% of which are in the 3,4 configuration and a portion of which is in the 1,2 configuration is provided. A copolymer of this type with a reduced crystallinity is synthesized with a much higher productivity than its homologues of ethylene and of butadiene, and also confers improved curing properties on rubber compositions.

Disclosed is a propylene-based resin composition comprising more than 15 parts by mass and 40 parts by mass or less of an ethylene/α-olefin copolymer (E1) and 4 to 20 parts by mass of an ethylene/α-olefin/diene copolymer (E2), and comprising also a propylene-based polymer (P1) having an amount of a n-decane-soluble part at 23° C. of 5 to 25% by mass, wherein the ethylene content of the n-decane-soluble part is more than 40% by mass and 60% by mass or less, a propylene homopolymer (P2) and an inorganic filler (F) [providing that the total amount of the components (P1), (P2), (E1), (E2) and (F) is taken as 100 parts by weight]. The propylene-based resin composition is capable of producing a molded article which is excellent in mechanical properties, unnoticeable flow marks, low gloss.

In at least one embodiment, a process of forming a polymer includes supplying a feed having one or more olefin monomers and a solvent; contacting the feed with a catalyst to form a reaction mixture; treating the reaction mixture in a first separator to form a first polymer-rich mixture; introducing the first polymer-rich mixture into a second separator; introducing a volatile component and/or inert component into the first separator, the second separator and/or a line between the first separator and the second separator; treating the first polymer-rich mixture to form a second polymer-rich mixture; and devolatilizing the second polymer-rich mixture to obtain the polymer.