利用酸敏感超支化聚缩醛制备聚乳酸多孔微球

发布时间：2018-07-17 04:32

【摘要】：通过缩醛转移聚合合成了一种具有酸敏感特性的超支化聚缩醛(HBPAs),对该聚合物降解行为的研究表明,该聚合物具有很强的酸敏感特性,在pH为5.0时,短时间内可发生迅速的降解,而在pH为7.4时,该聚合物基本不发生降解.利用该聚合物的酸敏感特性,其在弱酸性条件下降解速率远远超过PLA的降解速率,制备了多孔PLA微球.进一步研究发现,通过调控超支化聚缩醛(HBPAs)与PLA的投料比,可以线性调控PLA多孔微球的孔径尺寸,并拟合得到了线性方程.DSC结果以及对微球降解过程的观察表明,在共混微球内部,HBPAs与PLA会发生一定的相分离,使得在酸降解的过程中,更有利于微球内部的HBPAs组分发生降解.
[Abstract]:An acid-sensitive hyperbranched polyacetal (HBPAs) was synthesized by acetal transfer polymerization. The degradation behavior of the polymer was studied. When pH is 7.4, the polymer does not degrade. The porous PLA microspheres were prepared by using the acid-sensitive properties of the polymer and the degradation rate of the polymer was much higher than that of the PLA under weak acid conditions. It was found that the pore size of porous PLA microspheres could be adjusted linearly by adjusting the feed ratio of hyperbranched polyacetals (HBPAs) to PLA, and the linear equation .DSC results and the degradation process of the microspheres were obtained by fitting the results. The phase separation of HBPAs and PLA in the microspheres will lead to the degradation of HBPAs in the microspheres in the process of acid degradation.
【作者单位】：浙江大学高分子科学与工程学系;教育部高分子合成与功能构造重点实验室;
【分类号】：R318.08

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