2018/8/30 · After 60 h electrospinning, the PVA fibers was cross-linked with GA by placing the nascent composite membrane above a beaker in which the temperature of GA solution (3 wt%) maintained at 90 C for 3 h. The cross-linking reaction of PVA with GA is illuminated in Fig. 1, b, and the cross-linking treatment is to avoid PVA swelling and to ensure its long-term stability during MD experiment.