A new type of NaCS/PDMDAAC polyelectrolyte complex membrane prepared by interfacial reaction of sodium cellulose sulfate as polyanions and poly(dimethylallylammonium chloride)as polycations was proposed.The static con...A new type of NaCS/PDMDAAC polyelectrolyte complex membrane prepared by interfacial reaction of sodium cellulose sulfate as polyanions and poly(dimethylallylammonium chloride)as polycations was proposed.The static contact angle of the polyelectrolyte complex(PELC)membrane surface was measured to characterize membrane wettability.The effects of concentration of polyelectrolyte,molecular weight,and reaction time on contact angle were investigated.It was found that NaCS/PDMDAAC PELC membrane was hydrophilic.Its contact angle decreased with the increasing concentration of NaCS and molecular weight of PDMDAAC,and increased with the increasing concentration of PDMDAAC and reaction time.展开更多
氧气在微胶囊膜中的扩散行为将直接决定微囊内细胞的生长代谢行为。以海藻酸钠-壳聚糖聚电解质复合平板膜为研究模型,利用渗透池法,重点考察溶氧在膜中的扩散行为及其影响因素。结果显示:复合膜的扩散系数和孔隙率均低于海藻酸钙,复合...氧气在微胶囊膜中的扩散行为将直接决定微囊内细胞的生长代谢行为。以海藻酸钠-壳聚糖聚电解质复合平板膜为研究模型,利用渗透池法,重点考察溶氧在膜中的扩散行为及其影响因素。结果显示:复合膜的扩散系数和孔隙率均低于海藻酸钙,复合膜中溶氧扩散系数为(7～13)×10 10m2 s 1,为水中的23.3%～43.3%,孔隙率为93%～97%;扩散系数随海藻酸钠特性黏度的增大而减小,随壳聚糖分子量的增大而减小。微胶囊膜是氧传质主要的阻力部位,孔隙率、三维结构和材料极性是影响扩散性能的重要因素,改变海藻酸钠特性黏度和壳聚糖分子量可以改变膜孔隙率、结构和材料极性,进而调节膜扩散性能。展开更多
文摘A new type of NaCS/PDMDAAC polyelectrolyte complex membrane prepared by interfacial reaction of sodium cellulose sulfate as polyanions and poly(dimethylallylammonium chloride)as polycations was proposed.The static contact angle of the polyelectrolyte complex(PELC)membrane surface was measured to characterize membrane wettability.The effects of concentration of polyelectrolyte,molecular weight,and reaction time on contact angle were investigated.It was found that NaCS/PDMDAAC PELC membrane was hydrophilic.Its contact angle decreased with the increasing concentration of NaCS and molecular weight of PDMDAAC,and increased with the increasing concentration of PDMDAAC and reaction time.
文摘氧气在微胶囊膜中的扩散行为将直接决定微囊内细胞的生长代谢行为。以海藻酸钠-壳聚糖聚电解质复合平板膜为研究模型,利用渗透池法,重点考察溶氧在膜中的扩散行为及其影响因素。结果显示:复合膜的扩散系数和孔隙率均低于海藻酸钙,复合膜中溶氧扩散系数为(7～13)×10 10m2 s 1,为水中的23.3%～43.3%,孔隙率为93%～97%;扩散系数随海藻酸钠特性黏度的增大而减小,随壳聚糖分子量的增大而减小。微胶囊膜是氧传质主要的阻力部位,孔隙率、三维结构和材料极性是影响扩散性能的重要因素,改变海藻酸钠特性黏度和壳聚糖分子量可以改变膜孔隙率、结构和材料极性,进而调节膜扩散性能。
