摘要
研究了超临界二氧化碳中聚氨酯 ,乙烯醋酸乙烯共聚物和低密度聚乙烯等 3种聚合物对几种小分子的吸附作用 ,观测了吸附小分子后的聚合物的形态变化以及无水乙醇和乙酸乙酯在这 3种聚合物中的解吸 ,实验表明低密度聚乙烯吸附能力较差 ,不适作吸附的基体材料 ,而聚氨酯 ,乙烯醋酸乙烯共聚物吸附小分子能力较强。小分子在聚合物中按时间的自然指数形式递减规律解吸 ,解吸扩散系数数量级达 10 - 7cm2 /s。
A study was undertaken in supercritical carbon dioxide to investigate the adsorption of several kinds of small molecules into three kinds of polymers, i.e., polyurethane, ethylene-vinyl acetate copolymer and low-density polyethylene. Change in appearance of the polymers was observed. The weight changes of these polymers after adsorption were monitored by a simple gravimetric method. The result indicated that LDPE had a low adsorption of small molecules while PU and EVA had a good adsorption of small molecules. The weight change of polymers after treatment in mass with time showed a dependence on the logarithm of time and the diffusion coefficient was about 10 -7 cm 2/ s.
基金
国家自然科学基金!资助项目 (2 96 74 0 35)。
关键词
超临界二氧化碳
聚合物
解吸
小分子吸附
Supercritical carbon dioxide, Polymers, Adsorption, Desorption
