Polypropylenes having a reduced tendency to white fracture

US5686533A · kind A · utility

Assignee

• PCD Polymere Gesellschaft m.b.H. · AT

Inventors

• Markus Gahleitner · Ansfelden, AT
• Klaus Bernreitner · Linz, AT
• Norbert Hafner · Linz, AT
• Kurt Hammerschmid · Linz, AT
• Hermann Heinemann · Steyr, AT

Key dates

• Filing date: Oct 16, 1996
• Grant date: Nov 11, 1997
• Expiry date: Oct 16, 2016

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08L2205/02
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Polypropylenes having a reduced tendency to white fracture, which contain PA1 A) from 70 to 95% by weight of a highly isotactic polypropylene having anisotactic index of more than 90 and a melt flow index between 0.1 and 100 g/10 min, it being possible for the polypropylene to be a homopolymer of propylene or a copolymer of propylene with one or more .alpha.-olefins, having a propylene content of at least 50 mol %, and PA1 B) from 5 to 30% by weight of a highly amorphous polypropylene having a crystalline polypropylene fraction of up to 10% by weight with an enthalpy of fusion of not more than 40 J/g and a melt flow index between 0.1 and 100 g/10 min, it being possible for the polypropylene to be a homopolymer of propylene or a copolymer of propylene with one or more .alpha.-olefins, having a propylene content of at least 80 mol %.