中文摘要：

利用冻融循环法制备了羧基化多壁碳纳米管（MWCNTs）/聚乙二醇（PEG）-聚乙烯醇（PVA）复合水凝胶。考察了不同质量配比下MWCNTs/PEG-PVA复合水凝胶的微观形貌变化,并研究了复合凝胶的溶胀性能、拉伸强度、热稳定及导电性能。结果表明,加入MWCNTs后MWCNTs/PEG-PVA复合凝胶仍具有多孔的三维网状结构但孔径尺寸变小。当MWCNTs与PVA的质量比大于1.0∶100时,MWCNTs/PEG-PVA复合凝胶的孔洞均匀性降低。随着MWCNTs量的增加,MWCNTs/PEG-PVA复合凝胶的溶胀度及拉伸强度均先升高后降低。当MWCNTs与PVA的质量比为1.0∶100时,MWCNTs/PEG-PVA复合凝胶的溶胀度达到最大（1450%）,孔隙率最高（75.8%）,拉伸强度及断裂伸长率达到最大值,分别为0.97 MPa和384.0%。MWCNTs的加入提高了MWCNTs/PEG-PVA复合凝胶的热稳定性,MWCNTs/PEG-PVA复合凝胶的初始热分解温度从235℃上升至260℃;随着MWCNTs量的增加,MWCNTs/PEG-PVA复合凝胶的电导率从1.10×10-6 S/cm升高至6.96×10-4 S/cm。

英文摘要：

Carboxy-functionalized multi-walled carbon nanotubes （MWCNTs）/polyethylene glycol （ PEG）-poly- vinyl alcohol （PVA） composite hydrogels were prepared by the freezing/thawing method. The microstructure, swelling property, tensile strength, thermal stability and conductivity of MWCNTs/PEG-PVA composite hydrogels with different mass ratios were studied. The results show that the MWCNTs/PEG-PVA hydrogel still has a porous 3D structure, but the pore size becomes smaller after the addition of MWCNTs. When the mass ratio of MWCNTs to PVA is larger than 1.0：100, the uniformity of the porous structure of the MWCNTs/PEG-PVA hydrogel decreases. With the increment of MWCNTs content, the swelling degree and tensile strength of the MWCNTs/PEG-PVA composite hydrogel increase first and then decrease. When the mass ratio of MWCNTs to PVA is 1.0 ： 100, the swelling degree and porosity of the MWCNTs/PEG-PVA hydrogel reach the maximum （1450% and 75.8%, respectively）. The tensile strength and elongation reach a maximum value of 0.97 MPa and 384.0%, respectively. The addition of MWCNTs improves the thermal stability of the composite hydrogel, and the initial thermal decomposition temperature of MWCNTs/PEG-PVA composite hydrogel increases from 235℃ to 260℃. With the increment of the amount of MWCNTs, the conductivity of the composite hydrogel increases from 1.10×10^-6 S/cm to 6.96×10^-4 S/cm.