Investigation Of Aggregation Behavior And Mixing Performance Of α-capric Betaine Surfactant

αlong chain alkyl betaine is a new type of zwitterionic surfactant derived from natural oils and fats.The simple and economical synthesized route has been developed.In general, the betaine type zwitterionic surfactant is mild to the skin and eyes,exhibits low toxicity, displays excellent compatibility,good biologic degradation and resistance to hard water and high concentration electrolyte.The research onαlongchain alkyl betaine is useful in view of its broad prospects for practical application as a green surfactant.This thesis studies the aggregation behavior and the mixing performance of zwitterionic surfactantα-capric betaine(α-CB),and the main points are as follows:The steady-state fluorescence has been employed to determine the aggregation number ofα-capric betaine.The aggregation numbers have been found to increase with the increasing of the surfactant concentration and salt concentration.The temperature exhibit different effect on the aggregation numbers ofα-CB in different concentration region:the aggregation numbers increase with the increase of temperature at high concentration region, decrease slightly with the increase of temperature at low concentration region.The interaction in binary mixed systems betweenα-CB and the nonionic surfactant AEO₈,cationic surfactant DTAB,anionic surfactant SDS,SL has been studied respectively. The binary mixed system of SDS/α-CB exhibits extensive synergism performance both in the capability of mixed micelle formation and in the ability of surface tension reducing.But the mixed systems ofα-CB/DTAB andα-CB/SL were found to behave synergically only in the capability of micelle formation.And the surface tension of the mixed system ofα-CB and AEO₈ is similar to the ideal blend system.The application performance ofα-CB/SDS shows that the mixed system has better performance in wetting and foam stability.And the solubilizing and emulsifying ability of mixture surfactants forα-CB and SDS is stronger than that of single surfactant solution forα-CB obviously,the mixed sysem ofα-CB and SDS present maximum emulsification at the molar fraction 0.8 ofα-CB,and maximum solubilized amount at the molar fraction 0.2.