Three polyamidoamine(PAMAM) dendrimers have been synthesized by divergence method with ethylenediamine as core. The surface tensions of aqueous solution of different generation PAMAM were determined by traditional sur...Three polyamidoamine(PAMAM) dendrimers have been synthesized by divergence method with ethylenediamine as core. The surface tensions of aqueous solution of different generation PAMAM were determined by traditional surfactant method. The results showed that the whole PAMAM doesn′t have surface acti- vity and the half PAMAM have certain surface activity. Their critical micelle concentrations(CMC) were obtained from surface tension curves, and the hydrophile-lipophile balance number(HLB), saturated adsorption capacity, molecular cross section area and molecular diameter were calculated. The results revealed that the molecular diameter of 0.5G, 1.5G and 2.5G PAMAM were 0.743, 0.998 and 1.371 nanometer, respe- ctively. The dendrimer obtained was also proved to be of nanometer order.展开更多
A series of gemini surfactants 12-s-12 were successfully prepared and characterized,and their surface activities were evaluated by means of surface tension and electrical conductivity methods.The results showed that a...A series of gemini surfactants 12-s-12 were successfully prepared and characterized,and their surface activities were evaluated by means of surface tension and electrical conductivity methods.The results showed that all products have better surface activities.However,the space groups have a great influence on the surface activites of these gemini surfactants—the shorter the space group,the better the surface activities.展开更多
文摘Three polyamidoamine(PAMAM) dendrimers have been synthesized by divergence method with ethylenediamine as core. The surface tensions of aqueous solution of different generation PAMAM were determined by traditional surfactant method. The results showed that the whole PAMAM doesn′t have surface acti- vity and the half PAMAM have certain surface activity. Their critical micelle concentrations(CMC) were obtained from surface tension curves, and the hydrophile-lipophile balance number(HLB), saturated adsorption capacity, molecular cross section area and molecular diameter were calculated. The results revealed that the molecular diameter of 0.5G, 1.5G and 2.5G PAMAM were 0.743, 0.998 and 1.371 nanometer, respe- ctively. The dendrimer obtained was also proved to be of nanometer order.
文摘A series of gemini surfactants 12-s-12 were successfully prepared and characterized,and their surface activities were evaluated by means of surface tension and electrical conductivity methods.The results showed that all products have better surface activities.However,the space groups have a great influence on the surface activites of these gemini surfactants—the shorter the space group,the better the surface activities.
