A review of the early development of the thermodynamics of the complex coacervation phase separation.
A review of the early development of the thermodynamics of the complex coacervation phase separation.
复制标题
DOI：
10.1016/j.cis.2011.01.007
复制
发表时间：
2011-09-14
影响因子：
15.6
通讯作者：
Veis A
中科院分区：
文献类型：
--
作者：
Veis A
凝聚被定义为胶体分散体在相同的溶剂下分成富胶相(凝聚相)和贫胶相的现象。复凝聚是指两个电荷相反的聚合物多离子的混合物在同一溶剂中分成液体稀相和浓相，两相处于平衡状态，同时含有两种多离子。Voorn和Overbeek首次提出了复杂凝聚的理论分析，他们应用Flory-Huggins聚合物统计来模拟多离子及其反离子在溶液中的随机混合，假设每个相中的多离子完全随机混合，静电自由能ΔGelect提供驱动力。然而，实验上完全的随机性并不适用：多离子大小、异质性、链硬度和电荷密度(σ)都会影响平衡相分离和相浓度。此外，在稀散体系中，经常会观察到多相。作为另一种选择，Veis和Aranyi提出了形成电荷配对的对称聚集体(SA)的初始步骤，随后是由相互作用参数χ23驱动的相分离，该相分离结合了除ΔGelect静电项之外的熵和焓因素。这种平衡相分离的两阶段路径允许理解、量化和模拟具有不同电荷密度、σ和本征多离子结构的聚两性离子分子之间的相互作用产生的各种聚集体。
Coacervation was defined as the phenomenon in which a colloidal dispersion separated into colloid-rich (the coacervate), and colloid-poor phases, both with the same solvent. Complex coacervation covered the situation in which a mixture of two polymeric polyions with opposite charge separated into liquid dilute and concentrated phases, in the same solvent, with both phases, at equilibrium, containing both polyions. Voorn and Overbeek provided the first theoretical analysis of complex coacervation by applying Flory-Huggins polymer statistics to model the random mixing of the polyions and their counter ions in solution, assuming completely random mixing of the polyions in each phase, with the electrostatic free energy, ΔGelect, providing the driving force. However, experimentally complete randomness does not apply: polyion size, heterogeneity, chain stiffness and charge density (σ) all affect the equilibrium phase separation and phase concentrations. Moreover, in pauci-disperse systems multiple phases are often observed. As an alternative, Veis and Aranyi proposed the formation of charge paired Symmetrical Aggregates (SA) as an initial step, followed by phase separation driven by the interaction parameter, χ23, combining both entropy and enthalpy factors other than the ΔGelect electrostatic term. This two stage path to equilibrium phase separation allows for understanding and quantifying and modeling the diverse aggregates produced by interactions between polyampholyte molecules of different charge density, σ, and intrinsic polyion structure.
登录
查看更多内容
影响因子：
--
作者：
VEIS, A;ARANYI, C
通讯作者：
ARANYI, C
影响因子：
--
作者：
VEIS, A;ANESEY, J
通讯作者：
ANESEY, J
影响因子：
2.9
作者：
Dahl, T;Veis, A
通讯作者：
Veis, A
影响因子：
4.4
作者：
SCOTT, RL
通讯作者：
SCOTT, RL
影响因子：
2.9
作者：
VEIS, A;BODOR, E;MUSSELL, S
通讯作者：
MUSSELL, S