elastomeric copolymers of etheen and propene, methods for the preparation of these copolymers and mixtures on the basis of this isotaktisch polypropylene copolymers contain.

摘要

P the invention relates to elastomers of the copolymers of ethylene and propylene, in which the content of units ponderale derivatives of the ethylene is comprised between 34 and 67 and the content of units ponderale derivatives of propylene is between 33 and 66. / p & & p & these copolymers are characterized by the fact that at least 60 units derived from propylene are disposed in the sequences of at least three successive moieties and that their enthalpy of melting, measured after a heat treatment to determine, is lower at 15calg (calories per gram), and most often between 5 and 10calg. / p & & p & the copolymers of the invention may in particular be applied to the production of compositions of isotactic polypropylene. / p