Jiang Ping, Chen Shaowei, Lv Linda, Ji Hongmin, Li Gen, Jiang Zhechao, Wu Yiqiang
College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha 410004, Hunan, PR China.
J Nanosci Nanotechnol. 2020 Mar 1;20(3):1799-1806. doi: 10.1166/jnn.2020.17341.
The novel double responsive cellulose/poly 2-(dimethylamino) ethyl methacrylate (PDMAEMA) hydrogel was synthesized via free radical polymerization. The results from light transmittance measurements, scanning electron microscopy (SEM), mechanical property testing as well as swelling experiments demonstrated that DMAEMA played a significant impact on in hydrogel's nanostructure.With increasing DMAEMA concentration, the transparency of hydrogels dropped and texture became softer. The incorporation of relatively hard cellulose and increase in crosslink density significantly enhanced 3D network structure of hydrogel. The tensile strength, compression and bending capabilities of the composite responsive hydrogels were fine with the DMAEMA in a certain range. When the DMAEMA concentration increased to 6 g/g, the mechanical strength decreased noticeably. An increase in DMAEMA concentration resulted in a faster initial swelling rate and higher equilibrium swelling ratio. Further, three-dimensional structure and increase of DMAEMA concentration can also improve pH and temperature response sensitivity of hydrogels. Thus, the mechanical, swelling and responsive properties of hydrogel could be adjusted by the DMAEMA and polymerization modes.
通过自由基聚合反应合成了新型双响应性纤维素/聚甲基丙烯酸2-(二甲氨基)乙酯(PDMAEMA)水凝胶。透光率测量、扫描电子显微镜(SEM)、力学性能测试以及溶胀实验结果表明，DMAEMA对水凝胶的纳米结构有显著影响。随着DMAEMA浓度的增加，水凝胶的透明度下降，质地变得更软。相对坚硬的纤维素的加入和交联密度的增加显著增强了水凝胶的三维网络结构。在一定范围内，随着DMAEMA的加入，复合响应水凝胶的拉伸强度、压缩和弯曲性能良好。当DMAEMA浓度增加到6 g/g时，机械强度显著下降。DMAEMA浓度的增加导致初始溶胀速率加快和平衡溶胀率提高。此外，三维结构和DMAEMA浓度的增加还可以提高水凝胶的pH值和温度响应灵敏度。因此，水凝胶的力学、溶胀和响应性能可以通过DMAEMA和聚合方式进行调节。
