微凝胶增强聚丙烯酰胺水凝胶的制备及性能

Preparation and properties of microgel reinforced polyacrylamide hydrogel

以2-丙烯酰胺-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)、N,N'-亚甲基双丙烯酰胺(MBA)为单体,通过原位自由基聚合和机械破碎法制备了微凝胶(MG)悬浮液,将其与AM溶液复合,通过引发聚合制备了微凝胶增强聚丙烯酰胺双网络(MG-PAM DN)水凝胶。采用FTIR、SEM对MG-PAM DN水凝胶结构、形貌进行了表征,结合力学性能、溶胀性能和能量耗散性能测试,考察了MG悬浮液用量(以溶液总质量计,下同)对MG-PAM DN水凝胶性能的影响。结果表明,当MG悬浮液用量为40%时,制备的MG-PAM DN水凝胶呈现出致密的三维网络结构,平均孔径为20μm;其压缩强度可达25.42MPa(95%形变),拉伸强度和断裂伸长率分别可达201.2 kPa和450.4%,在不同应变(70%、80%)下均具有良好的能量耗散性能;MG-PAM DN水凝胶还可以承受弯曲、打结、按压、切割、提重等不同的机械作用。MG的引入增加了MG-PAM DN水凝胶内部的交联密度,形成了更加致密的网络结构,使MG-PAM DN水凝胶拥有更高的损耗模量和储能模量。

Microgel reinforced polyacrylamide double network(MG-PAM DN) hydrogel was synthesized from initiation polymerization by combining AM solution with microgel(MG) suspension,which was prepared by in-situ radical polymerization and mechanical crushing using 2-acrylamide-2-methylpropanesulfonic acid(AMPS),acrylamide(AM) and N,N'-methylenebisacrylamide as monomers,and then characterized by FTIR and SEM for structure and morphology analyses.The effects of MG suspension dosage(based on the total mass of solution,the same below) on the properties of MG-PAM DN hydrogel were investigated through combination with analyses data of mechanical properties,swelling properties and energy dissipation properties.The results showed that,when the dosage of MG suspension was 40%,the prepared MG-PAM DN hydrogel exhibited a dense three-dimensional network structure with an average pore size of 20 μm,compressive strength of 25.42 MPa(95% deformation),tensile strength and elongation at break of 201.2 kPa and 450.4%,respectively,and good energy dissipation performance under different strains(70%,80%).Moreover,MG-PAM DN hydrogel could withstand bending,knotting,pressing,cutting,lifting and other mechanical exertion.The introduction of MG increased the cross-linking density inside MG-PAM DN hydrogel and formed a denser network structure,resulting in higher loss modulus and energy storage modulus.