Wednesday, October 19, 2011
Exhibit Hall B (Minneapolis Convention Center)
Catalytic synthesis of Poly(butylene succinate) (PBS) by lipase was carried out through condensation polymerization of diethyl succinate and 1,4-butanediol using Diphenyl ether as solvent. Using Novozyme 435 as catalyst, the condensation polymerization started by 2 h pre-polymerization under atmospheric pressure, followed by 20 h polymerization under high vacuum (<10 mmHg) at 80~95 ºC. The product was characterized by FT-IR, 1H-NMR, 13C-NMR and gel permeation chromatography (GPC). The effects of monomer, the molar ratio of reactants and solvents on the polymerization were examined, respectively. The final product PBS with Mw of 44000 g/mol and Mn of 27,000 g/mol while a melting point of 114 ºC, is similar to that obtained by chemical synthesis, as well as thermal and mechanical properties determined by DSC and direct tension test. The biodegradability of this new PBS by lipase was also confirmed by scanning electron microscope (SEM). This novel property would ignite a great interest in the invention and application of new materials involving this new PBS synthesized with lipase as catalyst.