【摘要】 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)的半互穿网络水凝胶(CM C/PN IPAAm sem i-IPN)。研究了温度、pH对该凝胶溶胀度的影响。结果表明,在酸性(pH=1.0)和弱碱性(pH=7.4)条件下,sem i-IPN凝胶溶胀度均随着温度的升高而下降,但在pH=1.0时,sem i-IPN凝胶的溶胀度小于PN IPAAm凝胶的溶胀度;在pH=7.4时,结果正好相反。20℃时,该凝胶有良好的pH敏感性;而37℃时,敏感性不明显。同时对该凝胶的消溶胀动力学进行了研究,结果发现,该凝胶的消溶胀速率随着凝胶中CM C组分含量的增加而增大。更多还原

【Abstract】 A new kind of the semi-IPN hydrogels based on linear sodium carboxymethylcellulose (CMC) and cross-linked poly (N-isopropylacrylamide)(PNIPAAm), which exhibits pH and temperature sensitivities, was synthesized. The swelling behaviors of the semi-IPN hydrogel, which can act as a function of temperature and pH value of the medium, were investigated in detail, respectively. It is found that at acidic condition (pH=(1.0)) or weak alkaline condition (pH=(7.4)), the swelling ratios of the semi-IPN hydrogel decrease with increasing temperature, the swelling ratio of the semi-IPN hydrogel at pH=(1.0) is lower than those of pure PNIPAAm hydrogels, whereas the swelling ratio of the semi-IPN hydrogel at pH=(7.4) is higher than those of pure PNIPAAm hydrogels. The influence of pH on the swelling ratios of the semi-IPN hydrogel displays that pH-response of this hydrogel at 20 ℃ is more significant than that of at 37 ℃. In addition, the deswelling rate increases with increasing CMC content in the semi-IPN hydrogel at a temperature over the LCST(45 ℃).更多还原