交联改性对敷料用壳聚糖/聚氧化乙烯纳米纤维膜性能的影响

为改善壳聚糖基纳米纤维膜的耐水性和结构稳定性,对静电纺丝制得的壳聚糖/聚氧化乙烯(PEO)纳米纤维膜进行戊二醛交联改性,研究不同交联时间下纳米纤维膜在模拟人体缓冲液中微观形态结构、化学结构和结晶结构的变化,并对交联后纤维膜的耐水性和力学性能进行表征。结果表明:壳聚糖基纳米纤维膜经戊二醛交联处理后,在缓冲液中浸泡24 h纤维形态的稳定性得到明显改善,且随着交联时间的增加,纤维膜在缓冲液中的吸水率逐渐增加,溶失率逐渐降低;交联改性改变了壳聚糖大分子固有的结晶结构,使纤维膜的初始模量提高,力学强度随交联时间的增加先增加后降低。

Effect of cross-linking modification on properties of chitosan/polyoxyethylene nanofiber membranes towards wound care

In order to improve the structural stability and water resistance of chitosan-based nanofiber membranes, the glutaraldehyde cross-linking modification to the chitosan/polyoxyethylene nanofiber membranes prepared by electrospinning was carried out. Then,the nanofiber membranes of different crossing-linking time were immersed into phosphate buffer saline simulating body fluid environment in order to characterize its microstructure, chemical and crystalline structure, and the water resistance and mechanical properties was measured. The experimental results show that after glutaraldehyde cross-linking modification, the stability of the fiber structure is improved after soaking in the buffer for 24 h,and the water absorption ratio of nanofiber membranes in phosphate buffer saline gradually increases with the cross-linking time and the dissolution ratio gradually decreases, revealing that the cross-linking treatment has a positive effect on the structural stability and water resistance of the fiber membrane. It is also found that the cross-linking modification causes a strong interaction between the molecules, and changes the inherent crystalline structure of chitosan macromolecules, resulting in an increase in the initial modulus of the fiber membrane. In addition, the research shows that the mechanical strength of the nanofiber membranes increases first and then decreases with the extension of the cross-linking time. The cross-linking treatment increases both the strength and brittleness of the fiber membranes.