Ethylene 1,3 Butadiene copolymers having in their structure cyclopentane rings connected in a trans 1,2 position. The ethylene copolymers of the invention may be formed from polymerization of ethylene and 1,3 butadiene and preferably have a predominance of the copolymer units formed as trans 1,2-cyclopentane,...http://www.google.es/patents/US5191052?utm_source=gb-gplus-sharePatente US5191052 - Copolymers of ethylene and 1,3-butadiene
