Investigation of block/graft copolymerization of Styrene and ɛ-Caprolactone using Castor Oil and Ricinoleic Acid

In this work, the synthesis and characterization of new biodegradable graft copolymers have been studied. For this purpose, castor oil and ricinoleic acid were exposed to the oxygen of the air in the sunlight at room temperature. Thus, macroperoxide initiators were obtained for use in styrene polymerization. In the first part of the study, macroperoxide initiators polymerized styrene by free radical polymerization method to obtain graft copolymer series. The obtained graft copolymers were reacted with ε-caprolactone to cause ring opening polymerization. Thus, multi-block graft copolymers were synthesized. In the second part of the study, ring opening polymerization and free radical polymerization were used simultaneously. The peroxidated castor oil contains the carboxyl acid group and the peroxide group. Carboxyl acid groups polymerize ε-caprolactone by ring-opening polymerization, while peroxide groups polymerize styrene by free radical polymerization. In the last part of the study, PEG derivatives were synthesized by attaching polyetilene glycol (PEG) to the –OH ends of ricinoleic acid. The polymers were characterized by GPC, NMR, FT-IR, DSC techniques.