Stabilization of PVA/Chitosan/TiO2 Nanofiber Membrane with Heat Treatment and Glutaraldehyde Crosslink

Abstract

PVA/chitosan/TiO2 nanofiber membrane have been prepared by electrospinning method. PVA/Chitosan/TiO2 nanofibers are poor stability in water. In this paper, the stabilization of PVA/chitosan/TiO2 nanofiber membrane was improved by heat treatment and GA crosslink. The structure and morphology of PVA/chitosan/TiO2 nanofibers were characterized by FTIR, SEM, and EDAX. The result showed that the stabilization methods affected the morphology of nanofiber membranes and their stability in water. Heat treatment reduces fiber diameter and membrane pore size, in contrast, GA crosslink increase fiber diameter and membrane pore size. Stability in water of nanofiber membranes was examined by immersing in the water for 24 h. The SEM result shows that after immersing in water for 24 h, PVA/Chitosan/TiO2 nanofibers without stabilization rapidly shrink and dissolve after dipped in water and finally form transparent gel shape material with a grain of TiO2 nanoparticle. PVA/Chitosan/TiO2 nanofibers with heat treatment don’t dissolve after immersing but present a certain degree of aggregation and swelling, which indicates that heat treatment can improve the stability of the fiber but still low. Meanwhile, PVA/Chitosan/TiO2 nanofibers with GA crosslink do not dissolve and change morphology and fiber diameter after immersing 24 h. It indicates that PVA/Chitosan/TiO2 nanofibers with GA crosslink have excellent stability in water.