Preparation of grafted copolymers via oxidized polypropylene

A new and novel class of oxidized polypropylene containing bound peroxide functionalities can be used as polymerization initiators to produce polypropylene‐grafted copolymers. Upon heat treatment, the peroxide functionalities in the oxidized polypropylene act as a source of free radicals, reacting with the unsaturated double bonds of the monomer and initiating polymerization. The grafting reaction is carried out in the solid state in a reactor. The advantage of grafting via this new class of oxidized polypropylene is the elimination of expensive and environmentally unfriendly organic peroxides. A number of monomers have been grafted using oxidized polypropylene, including vinyl acetate, vinyl pyrrolidinone, methacrylic anhydride, and maleic anhydride. Oxidized polypropylene‐grafted copolymers are effective compatibilizers for PP/ETP blends and good coupling agents in glass‐ reinforced formulations. Preparation, characterization, and mechanical properties of terpolymers prepared from sequential grafting of oxidized polypropylene are also discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007