主链型不饱和聚磷酸酯交联体系体外降解性能

研究了主链重复结构单元中含富马酸酯的不饱和聚磷酸酯（UPPE）与N-乙烯基吡咯烷酮（NVP）交联体系的体外降解过程，采用扫描电镜观察了降解一定时间后试样断面的形态结构．结果表明：交联体系试样是按照先表层、后中心。由外至内的规律进行降解，降解过程包括表层扩散溶出和基体降解两部分．在表层扩散溶出占主导阶段。交联试样中聚乙烯基吡咯烷酮（PVP）和NVP快速溶出，试样失重明显，试样吸水率、长度、直径也迅速增大；在基体降解占主导阶段，试样降解比较缓慢，试样失重、吸水率、长度和直径变化较小．

In vitro degradation properties of unsaturated polyphosphoester containing unsaturated olefinic bonds in repeat units

This study investigated the in vitro degradation of polymeric networks formed by the cross-linking of unsaturated polyphosphoester(UPPE) and N-vinyl pyrrolidone(NVP).At certain degradation point,the cross-sectional morphology of dagradation sample was imaged by scanning electron microscopy(SEM).The result indicated that the surface of the samples degraded firstly,and then the core of the samples.The degradation process contained the diffusive phase and the erosion phase.When the degradation was dominated by the diffusion,the samples exhibited rapid poly(N-vinyl pyrrolidone)(PVP),NVP release,dramatic mass decrease,rapid increase of water absorption,length and diameter of sample.When the degradation was dominated by erosion,the samples degraded slowly,exhibited unremarkable changes in mass loss,water absorption,length and diameter.