功能性PVA基复合水凝胶的制备与性能研究.pdf

文档介绍：华侨大学
硕士学位论文
功能性PVA基复合水凝胶的制备与性能研究
姓名:高永康
申请学位级别:硕士
专业:高分子化学与物理
指导教师:肖聪明
20070101
摘要
摘要
本文将生物相容性良好的水溶性聚乙烯醇(PVA),与多糖高分子以化学(接枝
到淀粉分子链)或物理(与含羧基的羧化淀粉和羧甲基纤维素钠混合)的方式相结
合,再经冷冻-解冻过程形成物理交联水凝胶,并对其结构和性能之间的关系进行了
分析、探讨,得到了如下结果:
1)合成出不同侧链 PVA 分子量的 Starch-g-PVA,并制得相应的物理交联水凝
胶。DSC 和 WAXD 分析结果表明,Starch-g-PVA 物理凝胶的形成机理与 PVA 物理
凝胶相似,但其形成凝胶的能力受侧链分子量的制约,当侧链分子量低于 ×104
时即无法形成物理交联水凝胶。
2)制得均匀分散的 Starch-g-PVA/HA 复合凝胶,其再溶胀性能与 PVA/HA 的
相近。
3)制得不同比例的羧化淀粉与 PVA 的复合物理水凝胶,羧基的引入,增强了
组分间的相互作用,降低了复合物理凝胶的结晶度,提高了凝胶的再溶胀性,且与
羧化淀粉的取代度大小有关。
4)制得具有 pH 响应性的 CMC/PVA 复合水凝胶。随着 CMC 含量的增加,
CMC/PVA 复合凝胶的结晶度下降,凝胶网络中的自由体积增大,再溶胀性提高;
同时,对于环境 pH 的敏感性增强。以牛血红蛋白(HB)为模拟药物,对其释放性
能进行初步研究的结果表明,CMC/PVA 复合凝胶可用作水溶性蛋白质药物的载体,
其释放速率可通过 CMC 含量来加以调节。

关键词:聚乙烯醇,羧化淀粉,羧甲基纤维素,复合水凝胶,物理交联
V
Abstract
ABSTRACT
The physically cross-plex hydrogels of poly(vinyl alcohol) (PVA), a
water-soluble and patible polymer, and harides are derived from
chemical or physical mixing way and subject to freezing/thawing subsequently. To
mix PVA with harides in chemical or physical way, PVA is grafted onto
starch chains or simply blended with carboxylic derivative of starch and sodium
carboxyl methyl cellulose (CMC) respectively. The structure, properties and their
relationship of plex hydrogels are analyzed and discussed. The main results of
this paper are summarized as follows:
1. Starch-g-PVA physical hydrogel with a controlled PVA branch length was
prepared by freezing/thawing first. The result of DSC and WAXD indicated that the
starch-g-PVA physical hydrogel was formed based on the crystallization PVA branch
as the junction points. PVA branch length can be well controlled by adding chain
transfer agent during PVAc was grafting onto starch. The ability of starch-g-PVA to
form gel relied on the molecular weight of PVA. It was found that the starch-g-PVA
could not form hydrogel when the molecular weight of PVA branch was lower than
×104.
2. Starch-g-PVA/plex hydroge