A novel approach to determine the molecular overlap of polyelectrolyte using an ultrafiltration membrane

作者：Zhu Xinsheng; Choo Kwang Ho^*

来源：Colloids and Surfaces A: Physicochemical and Engineering Aspects , 2008, 312(2-3): 231-237.

DOI：10.1016/j.colsurfa.2007.06.062

• overlap concentration
• polyelectrolyte
• stirred flow ultrafiltration
• resistance-in-series model
• gyration radius

The overlapping of charged polymers (e.g., polyelectrolyte) in the liquid phase is one of the key parameters affecting the processing of the macromolecular solutions. This work focused on the development of a novel method for determining the overlap concentration of polyelectrolytes with stirred cell ultrafiltration (UF) techniques. A new, simplified equation that incorporated the resistance-in-series UF model into the osmosis phenomenon caused by polymers was developed, and then applied to estimate the threshold concentration for macromolecular overlap. The overlap concentrations of model polymers, such as poly(dimethylamine-co-epichlorohydrin-co-ethylenediamine) and poly(diallyldimethylammonium chloride), were evaluated with different, initial polymer concentrations and membrane pore sizes. In the correlation between In R-t/C-r and In C-r, the concentration where In R-t/C-r had the minimal value was referred to as the overlap concentration. The gyration radius of polyelectrolytes was calculated using the overlap concentration, which can provide insight into the understanding of the size of polymers and their rejections by membranes. Determining the overlap concentration of polymers with a UF membrane appeared to be viable and practical.

• 出版日期2008-1-15
• 单位苏州大学; 宿州学院