粒状温敏性水凝胶的溶胀行为

Study on the Swelling Processes of Temperature-sensitive Gel Beads

研究了具有温敏性的PNIPA粒状水凝胶在不同水溶液中的溶胀过程。考察了水溶液的离子强度、pH值、温度以及凝胶组成等因素对水凝胶溶胀速率和倍率的影响。研究发现,粒状PNIPA水凝胶粒子的溶胀很快,在1到2分钟内就能达到溶胀平衡。温度和凝胶的交联度是影响溶胀速率的主要因素。由于溶质改变了网络的亲水性或离子基团的作用强度,使得凝胶的溶胀速率和倍率也相应发生变化。

The swelling processes of thermo-sensitive poly(N-isopropylacrylamide-bis-sodium acylate, NIPA-Bis-SA) and poly(N-isopropylacrylamide, NIPA) hydrogel beads in aqueous solution were studied. The effects of ionic strength, pH value, temperature and component of the hydrogels were investigated. The gel beads were swollen very quickly and equilibrated just within two minutes in pure water and diluted aqueous solution of NaCl etc. The swelling ratio and speed depend on the hydrophilic and ionic groups in the hydrogels. Moreover, the influence of initial swelling temperature on the swelling ratio and speed is very sensitive.