聚两性电解质凝胶DMAEMA/AAc的紫外合成与性质研究

【作者】 陈延锋； 伊敏； 哈鸿飞；

【机构】 北京大学技术物理系；

【摘要】 本文通过紫外辐照引发聚合合成了含甲基丙烯酸-N,N-二甲氧基乙基酯(DMAEMA)和丙烯酸(AAc)的两性共聚凝胶。并对pH和离子强度对于平衡溶涨比的影响,pH值对凝胶溶涨动力学的影响进行了系统研究。结果表明,通过控制原料配比可以合成具有不同等电点的凝胶。不同的共聚凝胶存pH性质上表现出很大的共性,那就是在等电点(IEP)时平衡溶涨比最小。当pH偏离等电点时,平衡溶涨比迅速增大。在凝胶等电点附近,凝胶表现出明显的反聚电解质性质,离子强度增大,平衡溶涨比增大。溶涨动力学的研究结果表明,在IEP时溶涨过程为Fickian动力学,在其他pH值时,则表现出non-Fickian性质。更多还原

【Abstract】 Polyampholyte hydrogels containing dimethylaminoethyl methacrylate (DMAEMA) and acrylic acid(AAc) have been synthesized by VV-irradiation polymerization. Effect of pH and ionic strength on the equilibrium swelling ratios(ESR) and influence of pH on the swelling kinetics have been studied. It was found that each hydrogel with different component ratio has its own isoelectric points(IEP). The polyampholyte hydrogels showed minimal equilibrium swelling ratios at the IEP. As pH deviated from IEP. ESR would increase rapidly. Antielcetrolyte effect was observed for the hydrogel. Near the IEP, ESR increased when ionic strength increased. At other pH values, ESR would decrease with ionic strength increasing. The swelling kinetics of the hydrogels was studied. The swelling process turned out to be Fickian at IEP and non-Fickian when pH deviated from IEP.更多还原