Application of tin(IV) porphyrin complexes as novel catalysts for the synthesis of new copolyurethanes with cyclopeptide moiety

摘要

New electron deficient tin(IV) porphyrins were used as efficient catalysts for the reaction of 4,4a-methylene-bis-(4-phenylisocyanate) (MDI), with L-leucine anhydride cyclodipeptide (LAC) and polyethyleneglycol-400 (PEG-400) and the results were compared with those obtained in the presence of a commercial catalyst, dibutyltin dilaurate (DBTDL). Molar ratio of catalysts to MDI, polymerization reaction time, viscosity, and yield of the resulting poly(ether-urethane-urea)s (PEUU) were compared in the presence of different catalysts. The rate of N?C?O conversion in the presence of each catalysts under the same reaction conditions was also compared and followed by FT-IR N?C?O absorption band. FT-IR, GPC, and viscosity studies have shown that tin(IV) porphyrins afford higher viscosity and reaction progress.