氨基官能化聚乳酸电纺纤维的制备、表征和应用

Preparation,Characterization and Application of Amine-functionalized Poly(lactic acid) Electrospun Fibers

通过聚乳酸（PLA）和氨基丙基三乙氧基硅烷（KH550）混合进行静电纺丝制备氨基官能化聚乳酸纳米纤维。采用滴定法测定了纤维表面氨基含量，证明当 KH550的添加量为3%~13%（质量分数）时，有19%~26%的氨基出现在纤维的表面。利用场发射扫描电子显微镜、差示扫描量热（DSC）仪、接触角测试仪和电子拉伸机对纤维形貌、 PLA 的玻璃化转变温度和熔点以及纤维膜的亲水性和力学性能进行了表征。结果表明， KH550的加入可以在电纺纤维表面引入氨基，同时使纤维直径变细，使 PLA 的玻璃化转变温度上升，熔点下降，电纺纤维膜的亲水性略有增加，力学性能有所下降。通过吸附将金纳米粒子负载到氨基官能化聚乳酸电纺纤维膜上，得到负载型催化剂，对硼氢化钠还原对硝基苯酚的反应具有良好的催化活性和重复使用性。

Amine-functionalized poly（lactic acid）（PLA） nanofibers were prepared by co-electrospinning of PLA and aminopropyltriethoxysilane（KH550） in 1,1,1,3,3,3-hexafluoroisopropanol. The contents of amine groups on the surfaces of the fibers were measured by chemical titration. The results show 19% -26% of total amine groups appeared on the fiber surfaces when 3% -13% of KH550 to PLA is added. The amine-functionalized PLA nanofibers were also characterized by field emission scanning electron microscopy, differen-tial scanning calorimetry（DSC）, contact angle measurements and uniaxial tensile tests. It has been shown that the addition of KH550 can introduce amine groups on PLA fiber surfaces, meantime the fiber diameter decrea-ses, Tg of PLA increases, Tm of PLA decreases, the hydrophilicity of the fiber mat slightly increases and its mechanical properties decreases. Au nanoparticles were adsorbed on the surface of amine-functionalized PLA nanofibers, which showed good catalytic activity and reusability for the reduction of 4-nitrophenol.