聚丙烯酸钠/聚乙烯醇复合水凝胶的制备及其电响应行为

Preparation and Electrical Response Behavior of PAAS/PVA Composite Hydrogels

以过硫酸钾为引发剂,N, N′-二甲基双丙烯酰胺为交联剂结合冷冻-解冻交联,制备了一系列不同配比的聚丙烯酸钠(PAAS)/聚乙烯醇(PVA)互穿网络水凝胶,并用傅里叶红外光谱仪(FTIR)、场发射扫描电子显微镜(SEM)、热失重分析仪(TG)、万能试验机等对其进行表征。结果表明,PVA均匀分散于互穿网络水凝胶中,PVA的加入可以提高PAAS水凝胶的热性能;使PAAS水凝胶的溶胀速率和最大溶胀度减小,在PVA含量达到14%(质量分数,下同)时最低,随后又提高;PVA的加入可以显著提高其力学性能,断裂伸长率和拉伸强度均随PVA含量的增加而增大;PVA的加入提高了互穿网络的电响应灵敏度,且其最佳含量为21%。

A series of PAAS/PVA composite hydrogels with an interpenetrating network structure were prepared by using potassium persulfate as an initiator and N,N′-dimethylbisacrylamide as a crosslinking agent through a freeze-thaw cross-linking pathway, and their chemical structure and performance were characterized by means of Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy, thermogravimetric analysis (TG) and universal mechanical testing machine. FTIR characterization identified that the PVA was uniformly dispersed in the interpenetrating network-structured hydrogels. TG results indicated that the addition of PVA improved the thermal properties of the composite hydrogels. Moreover, the addition of PVA reduced the swelling rate and maximum swelling of the composite hydrogels, and incorporation of 14 wt.% PVA into PAAS led to a minimum swelling rate for the composite hydrogels. The introduction of PVA could significantly improve the mechanical properties of the composite hydrogels, and their elongation at break and tensile strength increased with an increase of PVA content. The electrical response experimental results indicated that the electrical response sensitivity of the composite hydrogels was improved due to the addition of PVA with an optimum content of 21 wt.% PVA.