聚氨酯-羧甲基壳聚糖席夫碱水凝胶的制备与性能

Preparation and properties of polyurethane- Carboxymethylation chitosan Schiff base hydrogel

摘要:

将2,4-二羟基苯甲醛（DDBA）作为扩链剂，丙烯酸羟乙酯(HEA)作为封端剂制备了含有醛基的水性聚氨酯（DPU），在温和的条件下引入羧甲基化壳聚糖（CMCh）合成了聚氨酯-CMCh席夫碱，再由自由基聚合法引入聚丙酰胺合成了聚氨酯-羧甲基壳聚糖席夫碱水凝胶（DPU-Ch）。通过FTIR、SEM、力学性能、溶胀保水试验、抗菌试验和血液相容性测试等对水凝胶结构和性能进行表征。结果表明，水凝胶的机械性能随着CMCh质量分数的增加而提升，同时水凝胶也显示出良好的溶胀能力和保水能力；当CMCh添加量为2%时，水凝胶对革兰氏阳性和阴性细菌菌株均显示出良好的抗菌性能；水凝胶溶血率均低于5%表明其具有良好的细胞相容性，NIH3T3细胞存活率在90%以上证明其没有细胞毒性，因此在生物医疗领域中具有潜在的应用前景。

Abstract:

Waterborne polyurethane(WPU) was prepared by using 2,4-dihydroxybenzaldehyde (DDBA) as the chain extender and hydroxyethyl acrylate (HEA) as the blocking agent. The polyurethane-CMCh Schiffbase was synthesized by the carboxymethylated chitosan (CMCh) under mild conditions. Then the polyurethane-carboxymethyl chitosan Schiff base (DPU-Ch) hydrogel was synthesized by free radical polymerization. The structure and properties of hydrogels were characterized by FTIR, SEM, mechanical properties, swelling water retention test, antibacterial test and blood compatibility test. The results show that the mechanical properties of the hydrogel increase with the increase of the CMCh mass fraction. At the same time, the hydrogel also shows good swelling ability and proper water retention capacity. When the amount of CMCh added is 2%, the hydrogel shows good antibacterial properties against E. coli and S.aureus; The hemolysis rate of the hydrogel is lower than 5%, indicating that it has good cell compatibility, and the survival rate of NIH3T3 cells above 90% proves that it is not cytotoxic, so It has potential application prospects in the field of biomedicine.