【摘要】 以L-乳酸和季戊四醇为原料,采用缩聚法合成了星形结构的聚L-乳酸(SPLLA)。用NMR、GPC、X射线衍射、粘度计等手段对聚合物的结构进行了表征,并证明了支化结构的存在。所合成的SPLLA分子量分布指数DI<1·2,特性粘度、均方根末端距均小于同分子量的线型聚L-乳酸(LPLLA)。反应速度明显快于同催化剂合成LPLLA时的反应速度,有利于合成较高分子量的聚L-乳酸。更多还原

【Abstract】 Star-shaped poly(L-lactic acid(SPLLA) was synthesized using L-lactic acid and pentaerythritol as starting material by means of polycondensation. The branched structure of the polymer was confirmed by characterization with nuclear magnetic resonance, gel permeation chromatography, X-ray diffraction spectrum and viscometry. The polydispersity index of synthesized star-shaped PLLA was below 1.2. The SPLLA show a smaller intrinsic viscosity, root-mean-square end-end distance than the linear one with same molecular weight, and an obviously faster reaction rate than the linear one in presence of same amount of catalyst was also seen. It was propitious to prepare poly(L-lactic acid with higher molecular weight.更多还原