A production method for a cyclic olefin copolymer which is capable of efficiently producing a cyclic olefin copolymer by copolymerizing monomers including a norbornene monomer and ethylene while suppressing the formation of a polyethylene-like impurity, and a catalyst composition for the copolymerization of a norbornene monomer and ethylene. Monomers including a norbornene monomer and ethylene are polymerized in the presence of a metal-containing catalyst, and the metal-containing catalyst has a structure in which a nitrogen atom is bonded to a transition metal of Group 4 of the periodic table and an atom of Group 15 of the periodic table.

The present disclosure provides a novel transition metal compound having excellent structural stability together with polymerization reactivity, and thereby is useful as a catalyst in preparing an olefin-based polymer, particularly, a high molecular weight and low density olefin-based polymer, and a catalyst composition including the same.

The present disclosure provides a novel transition metal compound having excellent structural stability together with polymerization reactivity, and thereby is useful as a catalyst in preparing an olefin-based polymer, particularly, a high molecular weight and low density olefin-based polymer, and a catalyst composition including the same.

This invention relates homogeneous (solution) polymerization of propylene at higher temperatures (80° C. or more) using bisindenyl metallocene catalyst compounds having long (at least 4 carbon atoms) linear alkyl groups substituted at the 2-position and substituted or unsubstituted aryl groups at the 4-position.

This invention relates homogeneous (solution) polymerization of propylene at higher temperatures (80° C. or more) using bisindenyl metallocene catalyst compounds having long (at least 4 carbon atoms) linear alkyl groups substituted at the 2-position and substituted or unsubstituted aryl groups at the 4-position.

This invention is based upon the unexpected finding that the reaction product of polyisobutylene and a silane can be incorporated into tire sealant formulations to greatly reduce the level of hysteresis exhibited by such sealant formulations which decreases the rolling resistance of the tire to improve fuel economy. This is made possible by the further unexpected fining that silanes will react with polyisobutylene by a reaction which is initiated with a peroxide. This invention more specifically discloses a sealant composition which is particularly useful in manufacturing self-sealing tires and which is comprised of (a) the reaction product of polyisobutylene and a silane; and (b) a reinforcing filler. The sealant compositions also contain a peroxide to facilitate partial degradation of the polyisobutylene rubber during the curing of the tire.

This invention is based upon the unexpected finding that the reaction product of polyisobutylene and a silane can be incorporated into tire sealant formulations to greatly reduce the level of hysteresis exhibited by such sealant formulations which decreases the rolling resistance of the tire to improve fuel economy. This is made possible by the further unexpected fining that silanes will react with polyisobutylene by a reaction which is initiated with a peroxide. This invention more specifically discloses a sealant composition which is particularly useful in manufacturing self-sealing tires and which is comprised of (a) the reaction product of polyisobutylene and a silane; and (b) a reinforcing filler. The sealant compositions also contain a peroxide to facilitate partial degradation of the polyisobutylene rubber during the curing of the tire.

A terpolymer of ethylene, of 1,3-butadiene and of an aromatic α-monoolefin is provided. The terpolymer contains more than 60 mol %, preferably at least 70 mol %, and preferably at most 90 mol % of ethylene units, at most 10 mol % of aromatic α-monoolefin units and 1,2-cyclohexanediyl units.

Such a diene terpolymer rich in ethylene units has the advantage of exhibiting a reduced, or even zero, crystallinity.

A terpolymer of ethylene, of 1,3-butadiene and of an aromatic α-monoolefin is provided. The terpolymer contains more than 60 mol %, preferably at least 70 mol %, and preferably at most 90 mol % of ethylene units, at most 10 mol % of aromatic α-monoolefin units and 1,2-cyclohexanediyl units.

Such a diene terpolymer rich in ethylene units has the advantage of exhibiting a reduced, or even zero, crystallinity.

The present invention is directed towards random-heterophasic propylene copolymers with a specific ratio of stiffness to impact balance and specific relation between glass transition temperature and comonomer content. The invention is further directed to articles comprising said random-heterophasic propylene copolymer and their use.