羧甲基纤维素钠/聚(N-异丙基丙烯酰胺)纳米复合水凝胶的制备及结构性能表征

以无机粘土为交联剂制备了具有温度、pH双重敏感特性的羧甲基纤维素钠/聚(N-异丙基丙烯酰胺)/粘土半互穿网络纳米复合水凝胶(CMC/PNIPA/Clay semi-IPN),并通过红外和透射电镜对其结构和形态进行了表征。在酸性(pH=1.2)和20℃条件下,分别研究了温度和不同pH缓冲液对该凝胶溶胀度的影响,测定了复合水凝胶的力学性能。结果表明:水凝胶中的粘土被剥离成单片层,且均匀分散在凝胶网络中,起交联剂的作用,而CMC以线性大分子的形态存在;CMC/PNIPA/Clay具有良好的温度、pH双重敏感特性;凝胶的断裂伸长率>1 000%。

Preparation and Characterization of Sodium Carboxymethylcellulose/Poly(N-isopropylacrylamide) Nanocomposite Hydrogel

Sodium carboxymethylcellulose(CMC)/poly(N-isopropylacrylamide)(PNIPA) semi-interpenetrating(semi-IPN) hydrogel was prepared incorporating CMC into PNIPA cross-linked by clay to form a new kind of nanocomposite hydrogel CMC/PNIPA/Clay was obtained.The structure was characterized using FT-IR and TEM.Mechanical properties and swelling behavior of CMC/PNIPA/Clay hydrogels at different pH were studied.In the hydrogel,clay is almost exfoliated and acted as a multifunctional crosslinker;CMC is existed in the form of linear chain.The hydrogel shows both temperature and pH sensitive properties.The elongation at break of CMC/PNIPA/Clay hydrogels is more than 1 000%.