摘要
聚乙烯醇(PVA)物理微晶水凝胶由于化学稳定性好、无毒、生物相容性好等特点,近年来成为物理微晶凝胶研究的模板聚合物。但其力学性能较差,如何提高凝胶的力学性能,拓展其应用范围一直是水凝胶领域的研究难点和热点。Hofmeister盐析效应是提升凝胶力学性能一种高效、绿色的制备手段,但之前的研究多集中在小分子无机盐对凝胶性能的影响,对聚电解质盐的盐析效应鲜见报道。本文研究了三聚磷酸钠(STPP)聚电解质对PVA凝胶性能的影响,系统比较了其与氯化钠及氢氧化钠处理的PVA凝胶;重点从微观形态和结晶结构两方面研究了聚电解质盐与小分子盐引起PVA凝胶的微观结构差异,并分析了结构与性能间的响应关系。聚电解质STPP处理的PVA凝胶薄膜应力达到了23 MPa,应变高达1 100%,断裂韧性(110 MJ/cm^(3)),比纯水凝胶提升55倍之多,并兼具良好的阻燃性能。
Polyvinyl alcohol(PVA)physical hydrogels are becoming a template polymer for the study of physical microcrystalline gels due to their good chemical stability,non-toxicity and biocompatibility.However,the mechanical properties are poor.How to improve the mechanical properties and expand their application scope is still a challenge.Hofmeister salting out effect is an efficient and green preparation method to improve the mechanical properties of gels.Previous studies mostly focused on the influence of small molecular inorganic salts(such as NaCl,Na_(2) SO_(4) etc.)on the gel properties,and the salting out effect of polyelectrolyte salts was rarely reported.In this paper,the effect of sodium tripolyphosphate(STPP)polyelectrolyte on the gel properties of PVA was studied and compared with the PVA treated with sodium chloride and sodium hydroxide.The microstructure difference of PVA gels caused by polyelectrolyte salts and small molecular salts was researched in detail in terms of microstructure and crystal structure,and the reasons for the difference in properties caused by the structural difference were analyzed.The stress of PVA gel film treated by STPP reached 23 MPa,the strain reached 1100%,and the fracture toughness(110 MJ/cm^(3))was 55 times higher than that of pure hydrogel.The gels also exhibit good flame retardancy.
作者
张宁
逄勇
张建明
段咏欣
ZHANG Ning;PANG Yong;ZHANG Jianming;DUAN Yongxin(School of Polymer Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,Shandong,China)
出处
《化学研究》
CAS
2023年第3期189-198,共10页
Chemical Research
基金
国家自然科学基金(51773103)。
