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以芳氧基稀土三(2,6-二叔丁基-4-甲基苯氧基)镧(La(OAr)3)为催化剂,通过加入少量(8.5 mol%)碳酸2,2-二甲基三亚甲基酯(DTC)与ε-己内酯(CL)进行无规共聚合,成功制备了低结晶度的脂肪族内酯-碳酸酯无规共聚酯(PCD)材料,并用1H-NMR、SEC、DSC和WAXS证明了产物的结构和性能.以聚ε-己内酯(PCL)和PCD为基质、以水杨酸为模型药物,通过静电纺丝的方法制备了载药量为8 wt%、直径为1μm的电纺纤维膜,并测试了其体外药物释放行为.结果表明,PCD电纺纤维膜显示了可控的药物缓释行为而PCL电纺纤维则呈现了药物暴释的现象.DSC和WAXS分析表明,这两个体系药物释放行为的差异是由基质结晶度的差别产生的.PCD电纺膜的结晶度(χc=40.3%)远远低于PCL电纺膜(χc=79.3%),且晶区也更加不完善,药物能更多更好地融合在非晶区中,并通过高分子链的热运动缓慢释放.
Using La (OAr) 3 (aryloxide) tris (2,6-di-t-butyl-4-methylphenoxy) lanthanum as catalyst, a small amount of 8.5 mol% 2,2- The low crystallinity aliphatic lactone-carbonate random copolyester (PCD) material was successfully prepared by random copolymerization of ε-caprolactone (DTC) and ε-caprolactone (CL) NMR, SEC, DSC and WAXS were used to confirm the structure and properties of the product.Polysaccharide was prepared by electrospinning using poly-ε-caprolactone (PCL) and PCD as matrix and salicylic acid as model drug 8 wt% and 1 μm diameter electrospun fibers were prepared and their in vitro drug release behavior was tested.The results showed that PCD electrospun fibers showed controlled drug release behavior and PCL electrospun fibers showed drug release .CDS and WAXS analysis showed that the difference of drug release behavior between these two systems was caused by the difference of matrix crystallinity.The crystallinity of PCD electrospun film (χc = 40.3%) was much lower than that of PCL electrospun film χc = 79.3%), and the crystal area is also more imperfect, the drug can be more and better integrated in the amorphous region, and slowly released by the thermal movement of the polymer chain.