JPH0476383B

PURPOSE:To obtain a composition having high grafting efficiency and useful as an adhesive, modifier, polymer-solubilizing agent, etc., by kneading a specific grafting precursor with a specific polymer under melting. CONSTITUTION:A polypylene polymer (A) is suspended in water and the suspension is added with (B) a vinyl monomer, (C) a radical (co)polymerizing organic peroxide of formula I (R1 is H or 1-2C alkyl; R2 is H or CH3; R3 and R4 are 1-4C alkyl; R5 is 1-12C alkyl, etc.; m is 1 or 2) or formula II (R6 is H or 1-4C alkyl; R7 is H or CH3; R8 and R9 are 1-4C alkyl; R10 is 1-12C alkyl, etc.; n is 0-2) and (D) a radical polymerization initiator having a decomposition temperature of 40-90 deg.C corresponding to a half-life of 10hr. The amount of the component B is 5-400pts.wt. per 100pts.wt. of the component A, that of the component C is 0.1-10pts.wt. per 100pts.wt. of the component B and that of the component D is 0.01-5pts.wt. per 100pts.wt. of A+B. The obtained aqueous suspension is heated and impregnated into the propylene polymer and the temperature is raised to obtain a grafting precursor. 1-99wt.% of the precursor is mixed with 99-1wt.% of a propylene polymer and/or a vinyl monomer and the mixture is kneaded under melting at 100-300 deg.C to effect grafting reaction.