Research Of Biodegradable Polyurethane Material Synthesis With Poly-ε-Caprolactone-co-Lactic Acid

Biodegradable materials have been researched for more than30years and become more and more interested in the recent years. Polyurethane is the perfect biodegradable material due to the universal sensitivity to the normal microbes. As well known, poly-ε-caprolactone (PCL) and polylactic acid (PLA) are good biodegradable materials, therefore materials with better biodegradable properties can be obtained by the copolymerization of PCL and PLA. Usually the polyethylene glycol (PEG) is introduced into the material to increase the water absorption thereby the biodegradation speed is increased. And in the isocyanate part, aliphatic isocyanate like hexamethylene diisocyanate is normally taken into the research, polyurethane obtained with this material has good biological compatibility and biodegradation, can be used as the biological material.In this study, poly-ε-caprolactone-co-lactic acid (PCLA) are synthesized through ring-opening polymerization, and biodegradable materials are prepared with this copolymer and HDI as the isocyanate component. In the synthesis process, PCLA with molecular weight of1500and2000are prepared with different initiaters like BDO, PEG400and PEG1000, and chain extenders BHB (BDO-HDI-BDO) and HBH (HDI-BDO-HDI) are also synthesized for the biodegradable materil preparation. In this study, the effect of reaction temperature, the synthesis sequence, the different chain extender to the target are investigated, also discussed the polyurethane properties made from these intermediates. The final results show that polyurethanes made with the prepolymer of HDI blocked PCLAs initialized with PEG1000, BDO as the chain extender have excellent overall properties. The tensile strength reaches16MPa, the elongation at break reaches689%, and the Molecular weight from82702to2743and the weight loss%reaches19.95%after168hours biodegradation in the buffer solution of KH2PO4and Na2HPO4.