The basic method for synthesizing syndiotactic polystyrene-delta-polybutadiene graft copolymers was investigated. First, the syndiotactic polystyrene copolymer, poly(styrene-co-4-methylstyrene), was prepared by the copolymerization of styrene and 4-methylstyrene monomer with a trichloro(pentamethyl cyclopentadienyl) titanium(IV)/modified methylaluminoxane system as a metallocene catalyst at 50 degrees C. Then, the polymerization proceeded in in argon atmosphere at the ambient pressure, and after purification by extraction, the copolymer structure was confirmed with H-1-NMR. Lastly, the copolymer was grafted with polybutadiene (a ready-made commercialized unsaturated elastomer) by anionic grafting reactions with a metallation reagent. In this step, poly(styrene-co-4-methylstyrene) was deprotonated at the methyl group of 4-methylstyrene by butyl lithium and further reacted with polybutadiene to graft polybutadiene onto the deprotonated methyl of the poly(styrene-co-4-methylstyrene)backbone. After purification of the graft copolymer by Soxhlet extraction, the grafting reaction copolymer structure was confirmed with H-1-NMR. These graft copolymers showed high melting temperatures (240-250 degrees C) and were different from normal anionic styrene-butadiene copolymers because of the presence of crystalline syndiotactic polystyrene segments. Usually, highly syndiotactic polystyrene has a glass-transition temperature of 100 degrees C and behaves like a glassy polymer (possessing brittle mechanical properties) at room temperature. Thus, the graft copolymer can be used as a compatibilizer in syndiotactic polystyrene blends to modify the mechanical properties to compensate for the glassy properties Of pure syndiotactic polystyrene at room temperature. (c) 2008 Wiley Periodicals', Inc. J Appl Polym Sci 112: 335-344, 2009