PURPOSE: To prepare a self-adhesive compsn. excellent in the heat resistance, weathering resistance, transparency ad stickiness to an adherend consisting mainly of a polyolefin by copolymerizing a (meth)acrylate ester, an ethylenically unsatd. functional monomer, and an unsatd. chlorinated polypropylene.

CONSTITUTION: A self-adhesive compsn. comprises a copolymer of 60-98.9wt.% (meth)acrylate ester, 0.1-10wt.% ethylenically unsatd. functional monomer, and 1-30wt.% unsatd. chlorinated polypropylene. Said unsatd. chlorinated polypropylene is compd. obtd. by reacting or mixing a chlorinated polypropylene consisting of structural units of formula I(wherein 0<x<1) with a chlorinated polybutadiene consisting of structural units of formula II(wherein 0≤y<1), and pref. has a chlorine content of 20-50% an MW of 5,000-50,000, and an iodine value of 100-150.