超支化表面活性剂乳状液的稳定性

Stability of Hyperbranched Surfactants Emulsion

以超支化不饱和聚(酰胺-酯)(HP)和琥珀酸单十二酰胺磺酸为原料,合成了系列超支化聚(酰胺-酯)表面活性剂HPSA,并对其进行了FTIR和EA表征。从宏观相分离、介观液滴粒度及微观界面膜稳定性3个尺度考察了取代度、pH、电解质浓度以及温度对HPSA-煤油乳状液稳定性的影响。结果表明,随着取代度的增加,HPSA的乳化能力先增大后减小;HPSA具有pH响应性,在酸性条件下疏水性较强,碱性环境下亲水性较强,可以在较宽的pH范围(6~11)形成稳定的乳状液;NaCl质量浓度小于1.5×105mg/L时,HPSA-4在油水界面上形成的界面膜强度高,Zeta电位低,乳状液稳定性较好;温度主要影响HPSA-4的分子热运动,使其在界面膜上的碰撞几率增大,乳状液在120℃以下稳定性较好。从微观上看,HPSA分子在水溶液中自组装形成不同亲水/亲油性质的胶束聚集体,使其具有较强增溶乳化煤油的能力。

A series of hyperbranched unsaturated poly(amide-ester)surfactants(HPSA)were synthesized from hyperbranched unsaturated poly(amide-ester)(HP)and succinate monododecamide sulfonic acid.These surfactants were characterized by FTIR and elemental analysis(EA).The influences of degree of substitution,p H value,electrolyte concentration and temperature on the stability of HPSA-kerosene emulsion from macroscopic phase separation,mesoscopic droplet size and microscopic interface film stability.The results showed that the emulsifying ability of HPSA first increased and then decreased with the increase of degree of substitution.HPSA exhibited a pH response in aqueous solution,which was more hydrophobic under acidic conditions,and more hydrophilic under alkaline conditions and it could form a stable emulsion in a wide pH range(6~11).When NaCl mass concentration was less than 1.5×105 mg/L,the interface film formed by HPSA-4 at the oil-water interface had high strength,low Zeta potential and good emulsion stability.Temperature mainly affected the molecular thermal motion of HPSA-4,which made the collision rate of the emulsion increase.The emulsion had better stability at 120℃.Microscopically,HPSA molecules could self-assemble into micelle aggregates with different hydrophilic/lipophilic properties in aqueous solution,which made it had stronger ability of solubilizing and emulsifying kerosene.