基于随机共聚高分子溶液的格子模型,建立了一个可以描述温度和pH双重响应的随机共聚高分子凝胶溶胀行为的分子热力学模型。该模型考虑了溶剂与不同高分子的混合、高分子网络的弹性以及包含小分子离子在凝胶内外分布的Donnan平衡和聚合物网络上的大分子离子及其反离子之间的静电相互作用的离子影响对化学势的贡献。与其他模型不同的是,该模型还考虑了高分子的组成f。该模型有两类可调的模型参数,一类是溶剂与不同高分子网络之间的相互作用能参数ε槇ij,另一类是高分子网络自身的尺寸参数Mc。研究结果表明,该分子热力学模型只需较少的模型参数就可较好地描述温度和pH双重敏感的随机共聚高分子凝胶的溶胀行为。
Based on the lattice model of random polymer solution,a new molecular thermodynamic model for describing the swelling behavior of temperature and pH-sensitive random copolymer gels was developed.This model considers three contributions of chemical potential:mixing of different polymer and solvent,elasticity of polymer network,and ionic effect with Donnan equilibrium of ions distributed inside and outside gels and electrostatic interactions between the charges carried by polymer network and counter ions.Compared with other models,this model considers the composition of two polymers f.Two kinds of model parameters are included,which are the interaction energy parameters between polymer network and solvent εij,and a size parameter,which is the molecular weight of the network between two cross-linking points Mc.The results show that this model can describe the swelling behavior of temperature and pH-sensitive random copolymer gels by using fewer model parameters.