Some peculiar features of radiation grafting of monomers of various structures and reactivities onto polyolefins

Some peculiar features were studied for radiation grafting of monomers of v arious structures and reactivities in radical polymerization onto polyolefi ns (polyethylene and polypropylene). From the point of view of the kinetics and mechanism of grafting, the monomers are divided into two classes: The first class includes all monomers active in radical polymerization. When ir radiated together with the polymeric matrix, they are grafted onto it as lo ng polymeric chains and parallel to this occurs homopolymerization. The sec ond class includes nonactive or slightly active monomers for radical polyme rization. They are characterized by the formation of single units or short grafted chains. The possibility to add nonactive monomers with high radiati on chemical yields was demonstrated. A mechanism was proposed to explain hi gh radiation yields for a number of nonactive monomers by transferring the radical state along and/or between polymer macromolecules. (C) 2000 John Wi ley & Sons, Inc.