PMIA@PVDF同轴电纺纤维膜的制备及其油水分离性能研究

Preparation and oil water separation performance of PMIA@PVDF coaxial electrospun nanofibrous membrane

以聚间苯二甲酰间苯二胺(PMIA)为芯、聚偏氟乙烯(PVDF)为壳,使用22-17G同轴静电纺丝针头制备不同纺丝液芯壳流速比的PMIA@PVDF同轴电纺纤维膜,对纤维膜的芯壳结构、力学性能、热性能及油水分离性能进行了表征。结果表明:在纺丝液芯壳流速比为35时,PMIA@PVDF同轴电纺纤维膜具有理想的表面形貌和芯壳结构,具有较好的力学性能和热性能,且具有最佳疏水性和油水分离性能;纤维膜的纤维直径分布较为均匀,很少出现不规则的细丝,有比较分明的分层结构,PVDF包裹PMIA比较均匀;纤维膜的拉伸强度为10.42 MPa,断裂伸长率为38.76%;纤维膜在250℃有轻微的质量损失,最终质量保持率高于纯PVDF电纺纤维膜;纤维膜的水接触角达145.7°,对油水混合物(二氯甲烷-水、三氯甲烷-水)的分离流量都在1900 L/(m^(2)·h)之上、分离效率均达99%以上。

Using polyisophthaloyl m-phenylenediamine(PMIA)as the core and polyvinylidene fluoride(PVDF)as the shell,PMIA@PVDF coaxial electrospun nanofibrous membranes were prepared from the spinning solutions with different core-to-shell flow rate ratio by using a 22-17G coaxial electrospinning needle.The core-shell structure,mechanical properties,thermal properties and oil water separation performance of the nanofibrous membranes were characterized.The results showed that the PMIA@PVDF coaxial electrospun nanofibrous membranes possessed satisfying surface morphology and core-shell structure,good mechanical properties and thermal properties and optimal hydrophobicity and oil water separation performance when the core-to-shell flow rate ratio of spinning solution was 35;the nanofibrous membrane showed the relatively uniform fiber diameter distribution with few irregular filaments,distinct layered structure and the relatively uniform PVDF wrapped PMIA;the tensile strength and elongation at break of the nanofibrous membrane were 10.42 MPa and 38.76%,respectively;the nanofiberous membrane had slight mass loss at 250℃,and the final mass retention rate was higher than that of pure PVDF electrospun fiber membrane;and the water contact angle of the nanofiberous membrane was 145.7°and the separation flow rate of oil-water mixture(dichloromethane-water and trichloromethane-water)above 1900 L/(m^(2)·h),and the separation efficiency above 99%.