Synthesis And Characterization Of Poly(Butyiene Itaconate)

The application of polymer materials made our daily life more comfortable and convenient. However, it also causes serious environmental problems because they are hard to degrade in nature. Therefore, development of biodegradable polymers will help to improve the capability and expanding its applicaiton field. Aliphatic polyesters, with outstanding biodegradability, bioabsorbability and biocompatibility, have attracted great interest of researchers in recent years. While the aliphatic polyesters obtained from petrol are not biobased materials, although they are biodegradable. In this paper, a novel unsaturated aliphatic polyesters was prepared with a biomass material-itaconic acid, and had enhanced its structural properties by crosslinking. In addition, the biodegradability of polyester was studied.In this article, the hydroxyl-terminated unsaturated aliphatic polyester-poly(butyene itaconate)(PBI) was prepared from itaconic acid (IA) and1,4-butanediol (BD) by direct esterification-polycondensation method. The effects of mole ratio of BD to IA, the kind of catalyst, the content of catalyst, reactive temperature, reactive time and nitrogen (N2) on the polyester were discussed. The resultant polyester was characterized by fourier transform infrared (FT-IR) spectroscopy and1H nuclear magnetic resonance (1HNMR) spectrum. The optimal conditions was that the mole ratio of BD to IA was1.05, SnCl2as catalyst, catalyst content was0.16%(the mole ratio to itaconic acid), esterification temperature at N2was150℃, polycondensation temperatrue was180℃under low air pressure (-0.1MPa).Two kinds of methods were used for crosslinking modification of PBI: heat-crosslinked and styrene-crosslinked. While PBI was heat-crosslinked at185～200℃, its crosslinking degree increasesed with time and the rising of temperature. While PBI was crosslinked with styrene, its crosslinking degree rised with the increasing content of styrene. Thermogravimetric analysis (TGA) shows that the operating temperature of polyester was rised after crosslinked.The enzymatic degradation was performed in phosphate buffer solution with porcine pancrease lipase (pH=7.4), and characterized by weight remaining. The results showed that the biodegradability of PBI decreased with the increasing molecular weight. Biodegradability of PBI decreased after crosslinked, and the higher crosslinking degree,the slower enzymatic degradation.