PURPOSE: To obtain graft propylene copolymers which exhibit high graft ratio and improved bonding strength without using a peroxide.
CONSTITUTION: The propylene copolymers comprise a random propylene copolymer (I) with 0.1-15 wt.% polymerized 2-10C 1-alkenes and a random propylene copolymer (II) with 15-80 wt.% polymerized 2-10C 1-alkenes and are grafted with an α,β-ethylenically unsaturated carboxylic acid or carboxylic acid derivatives. They are obtained by reacting the graft monomer with the propylene copolymer under a pressure of 1-300 bar, wherein 0.01-1.0 wt.% (based on the propylene copolymer) of the graft monomer is mixed with the molten propylene copolymer in the absence of a free radical initiator, and the grafting reaction is carried out at 200-350°C.
PATORITSUKU MIYURAA
YURUGEN KERUTO
