Molecular characterization of sodium poly(acrylate) by an aqueous g.p.c./LS method

The molecular characterization of a commercial sample of sodium poly(acrylate) (NaPA) has been carried out by a g.p.c./LS method in 0.3 N NaCl at 25°C. The sample is fractionated into eight fractions. The agreements between the weight-average molecular weights of the NaPA fractions determined by light scattering and those measured directly by the g.p.c./LS method are excellent. Universal calibration is established for both the standard poly(ethylene oxide) and the NaPA fractions. The degree of branching for the fractions with high molecular weights are estimated using the experimental results obtained by the g.p.c./LS method.