PEG含量对水性可降解聚氨酯性能的影响简

本文采用“预聚-乳化法”合成了软段为聚（ε-己内酯）（PCL）和聚乙二醇（PEG），硬段为异佛尔酮二异氰酸酯（IPDI）和小分子扩链剂的无毒水性可降解聚氨酯（PCLPU），通过红外光谱（FTIR）和差示扫描量热（DSC）曲线分析、偏光显微镜（PLM）观察以及相对分子质量、水接触角和降解失重测定，研究了PEG含量对聚氨酯微相分离程度、软段结晶性能和降解行为的影响。发现随着PEG含量的增加，PCLPU的微相分离程度增加，软段PCL的结晶受到阻碍。材料的亲水性和结晶性对PCLPU的降解影响明显，当PEG和PCL比例（PCLPU50）适当时，所获得的亲水性、酯基含量以及结晶程度均适中，这时材料的降解速率最快。细胞毒性测试表明PCLPU降解液质量浓度低于1 mg/mL时，细胞生长正常。此类水性无毒可降解聚氨酯将在生物工程领域具有广阔的应用前景。

Effect of polyethylene glycol on the properties of biodegradable waterborne polyurethane

A series of nontoxic waterborne biodegradable polyurethanes （PCLPU）have been synthesized using IPDI,DMPA and L-lysine as the hard segment,PCL and PEG as the soft segment.The structures and properties of these PCLPUs were character-ized by Fourier transform infrared spectroscopy （FTIR）,differential scanning calorimetry （DSC）,gel permeation chromatogra-phy （GPC）,water contact angle （WCA）and polarizing light microscope （PLM）.The degree of microphase separation of PCLPUs increased and the crystallinity of PCL was decreased with the increase of PEG content.Alternatively,the biodegradable rates of PCLPUs were closely related to their hydrophility and crystallinity,and especially,these PCLPUs had relatively faster degradation rate when their PCL/PEG ratio was close to one.In vitro cytotoxicity analysis suggests that PCLPUs degradation products showed no significant inhibitory effect against fibroblasts at lower concentrations （〈1 mg/mL）.Thus,these water-borne biodegradable polyurethanes should have potential applications in the biomedical engineering.