Thermoplastic compositions of isotactic propylene polymers and flexible propylene polymers having reduced isotacticity and a process for the preparation thereof

摘要

Described is a thermoplastic composition including:;(A) 10 to 99% by weight of a propylene polymer optionally containing from 0.1 to 5% by moles of units derived from an olefin of the formula CH₂CHR, R being hydrogen, a C₂-C₂₀-alkyl or a C₆-C₁₂-aryl group, having the following characteristics:;50isotactic triads (mm)85;;melting point (Tm) from 60 C. to 120 C., and;(B) 1 to 90% by weight of a propylene polymer having an essentially isotactic structure, optionally containing from 0.1 to 5% by moles of units derived from an olefin of the formula CH₂CHR, R being hydrogen, a C₂-C₂₀-alkyl or a C₆-C₁₂-aryl group, which has a melting point (Tm) higher than 153 C. Also described is a process for the preparation of this thermoplastic composition.