Patent ID: 6204348
Filing Date: 2001-03-20
Classification: C08F,Y10S

Abstract:
A modified propylene homopolymer of improved processability produced by a continuous method from a propylene homopolymer having a melt index of 0.05 to 35 g/10 min at 230.degree. C./2.16 kg and an ethylenically unsaturated, multifunctional monomer, in which the propylene homopolymer, in particulate form as powder, granulate or grit having particle sizes in the range of 0.001 to 7 mm, is treated with a gas mixture which consists of 5 to 65% by volume of ethylenically unsaturated, multifunctional monomer, which is readily volatile, and 95 to 35% by volume of inert gas or oxygen or an inert gas-oxygen mixture in any mixing ratio, whereina) the treatment is conducted in a continuous mixer, with the gas mixture at a temperature of 20.degree. C. to 120.degree. C. and an average residence time of 10 seconds to 1,000 seconds and the particulate propylene homopolymer is in the solid phase, whereby the readily volatile, ethylenically unsaturated monomer is absorbed into the particulate propylene homopolymer without condensation of the readily volatile, ethylenically unsaturated monomer at the surfaces of the particulate propylene homopolymer in a proportion of 0.05 to 2% by weight, based on the weight of the particulate propylene homopolymer, without grafting thereonto,b) the particulate propylene homopolymer into which the readily volatile, multifunctional, ethylenically unsaturated monomer has been absorbed is melted under an atmosphere of said gas mixture at 110.degree. C. to 210.degree. C. during a residence time of 0.3 to 8.0 minutes whereby at least most of the multifunctional, ethylenically unsaturated monomer grafts onto the propylene homopolymer,c) the melt thereupon is heated to a temperature of 220.degree. C. to 300.degree. C. during a period of 0.3 to 7.0 minutes, unreacted, readily volatile, multifunctional, ethylenically unsaturated monomer and decomposition products being removed, andd) the melt is granulated.