TY - JOUR
T1 - A novel approach to determine the molecular overlap of polyelectrolyte using an ultrafiltration membrane
AU - Zhu, Xinsheng
AU - Choo, Kwang Ho
PY - 2008/1/15
Y1 - 2008/1/15
N2 - 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 ln Rt/Cr and ln Cr, the concentration where ln Rt/Cr 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.
AB - 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 ln Rt/Cr and ln Cr, the concentration where ln Rt/Cr 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.
KW - Gyration radius
KW - Overlap concentration
KW - Polyelectrolyte
KW - Resistance-in-series model
KW - Stirred flow ultrafiltration
UR - http://www.scopus.com/inward/record.url?scp=36849033061&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfa.2007.06.062
DO - 10.1016/j.colsurfa.2007.06.062
M3 - Article
AN - SCOPUS:36849033061
SN - 0927-7757
VL - 312
SP - 231
EP - 237
JO - Colloids and Surfaces A: Physicochemical and Engineering Aspects
JF - Colloids and Surfaces A: Physicochemical and Engineering Aspects
IS - 2-3
ER -