采用分子动力学模拟方法研究了由带电链节与不带电的中性链节组成的交替共聚物和随机共聚物与带相反电荷表面活性剂的相互作用,考察了随机和交替共聚物中中性链节的亲、疏水性对所形成复合物的影响。结果表明,当共聚物中中性链节表现为亲水特性时,交替与随机共聚物吸附表面活性剂分子的能力差别不大,在所模拟的浓度区间内,两种聚电解质与表面活性剂均形成瓶刷结构。当中性链节表现为疏水特性时,带电链节的交替分布和随机分布不仅影响了其吸附表面活性剂的能力,也影响了复合物的最终结构。在所考察的表面活性剂浓度范围内,疏水性的随机共聚物与表面活性剂相互作用会形成较大的聚集体,而疏水性的交替共聚物与表面活性剂的作用仅能形成瓶刷结构以及较小的聚集体。
The interaction between alternative/random polyelectrolyte composed by charged and neutral blocks and negatively charged surfactants were studied by molecular dynamics simulations.The effects of hydrophilicity or hydrophobicity of neutral block of the alternative/random copolymer on the microstructure of the formed complex were investigated.The results show that the difference of adsorption abilities for alternative/random copolymer is negligible when the neutral blocks of polymer are hydrophilic and the bottle-brush complexes are observed for both systems in the range of studied surfactant concentrations.However,the distribution of the charged blocks alternatively and randomly in polymers affects both the adsorption abilities to surfactants and the microstructure of the formed complex when the neutral blocks are hydrophobic.The bigger aggregates are formed in the system composed by hydrophobic random copolymer and surfactant and both of the bottle-brush complex and smaller aggregations are observed in the mixed system of hydrophobic alternative copolymer and surfactant.