含硅水凝胶角膜接触镜材料的脱水行为

Dehydration behavior of hydrogel membrane containing silicane

采用重量法研究了γ–(甲基丙烯酰氧)丙基三甲氧基硅烷(KH570)与甲基丙烯酸–2–羟基乙酯(HEMA)及N–乙烯基吡咯烷酮(NVP)共聚物水凝胶角膜接触镜材料的脱水行为。结果表明,含硅水凝胶接触镜材料的脱水机理可采用两种极限情况下的幂律模型来描述,即脱水动力学级数n=0.5和n=1;当n=1时,水凝胶的失水率(Mt/M0c)与时间t成正比,为蒸发阶段;随后的脱水阶段中n=0.5,水凝胶的Mt/M0c与时间t1/2成正比,为扩散阶段;含硅水凝胶接触镜材料的脱水速率随单体NVP和KH570含量增大而降低,随脱水温度的升高而提高,随盐离子浓度的增加而降低。

In this paper, the dehydration behavior of copolymer hydrogel membrane of KH570 with N-vinylpyrrolidone （NVP） and hydroxyethylmethacrylate （HEMA） was studied. The results showed that the dehydration mechanism could be described by two models, one was the order of kinetics being 1 and the other was the order of kinetics being 0.5. For the order of kinetics 1, it was the initial dehydration and was characterized by the evaporation of water; while for the subsequent order of kinetics 0.5, it was characterized by the diffusion of water. The dehydration rate of the hydrogel membrane increased when the temperature and the content of NVP or KH570 increased, while the dehydration rate decreased when the content of NaCl increased.