PRODUCTION OF POLYOLEFINS HAVING IMPROVED PROPERTIES

摘要

A process for producing polypropylene having increased melt strength, the process comprising (i) homopolymerising polypropylene or copolymerising propylene with one or more comonomers selected from ethylene and C4 to C10 1-olefins to produce a polypropylene homopolymer or copolymer respectively having a double bond concentration of at least 0.1 per 10,000 carbon atoms, (ii) irradiating the polypropylene with an electron beam having an energy of at least 5 MeV and at a radiation dose of at least 5 kGray, and (iii) melting and mechanically processing the melt of polypropylene to form long chain branches on the polypropylene molecules.