碳酸乙烯酯对聚己内酯/冰乙酸电纺纤维的影响

Effect of Ethylene Carbonate on Fibers of Polycaprolactone/Glacial Acetic Acid System by Electrospinning

在聚己内酯(PCL)/冰乙酸(GAC)溶液体系中加入低毒低挥发性溶剂碳酸乙烯酯(EC),采用静电纺丝法成功制备纳米纤维,采用扫描电子显微镜研究了不同EC浓度对制得的纤维形貌和直径的影响。结果表明,当溶液中PCL质量分数为20%,EC体积分数从0%变化到9%时,纳米纤维数量增加,平均直径逐渐变小;当EC体积分数从9%变化到15%时,微米纤维或珠串状纤维数量开始增加,平均直径逐渐变大。对比研究了EC体积分数为9%的溶液与未加EC的溶液的纺丝稳定性,同时对比研究了由这两种溶剂分别制备的纳米纤维膜和微米纤维膜的结构和性能。结果表明,PCL/GAC/EC溶液体系黏度可在24h内保持稳定,满足连续电纺要求;X射线衍射测试结果表明两种纤维膜结晶构型一致,只是结晶度和晶粒大小有所区别;傅里叶变换红外光谱分析结果表明EC对PCL的化学结构没有影响;与微米纤维膜相比,纳米纤维膜的比表面积提高了362.6%,平均孔直径有所减小,接触角有所增大;纳米纤维膜的拉伸断裂应力稍大但断裂应变明显小于微米纤维膜。

Less toxic and nonvolatile solvent ethylene carbonate(EC)as the addition was utilized in polycaprolactone(PCL)/glacial acetic acid(GAC)solution system to successfully fabricate nanofibers by electrospinning.The influences of EC concentration on the fiber morphology and diameter were studied.The results show that,when mass fraction of PCL in the solution is 20%,the number of nanofibers increases and the average fiber diameter decreases as EC volume fraction varies from 0%to 9%,the number of microfiber or beaded fiber begins to increase and the average fiber diameter gradually becomes larger as EC volume fraction changes from 9%to 15%.Then,the spinning stability of the PCL/GAC solutions with 9%of EC volume fraction and without EC were compared,the structure and properties of the nanofiber membrane obtained under the former solution system were compared with the microfiber membrane prepared under the latter solution system.The results are as follows,The viscosity of PCL/GAC/EC solution system is stable in natural status within 24 h,meeting the requirement of continuous electrospinning.X-ray diffraction results show that the crystal structure of the two membranes are the same,just with different crystallinity and grain size.Fourier infrared spectroscopy results show that EC has no effect on the chemical structure of PCL.Compared with the microfiber membrane,the specific surface area of the nanofiber membranes is improved by 362.6%,the average pore diameter decreases and contact angle increases,the tensile fracture stress of the nanofiber membranes is slightly larger but the fracture strain is significantly smaller than that of the microfiber membranes.