CHARACTERIZATION OF BENZENE AS A SOLVENT FOR POLY(2-VINYLPYRIDINE)

Static and dynamic light scattering and intrinsic viscosity measurements have been performed on dilute solutions of poly(2-vinylpyridine) in benzene. Several workers have reported a THETA-point for this system in the range of 11-16-degrees-C as determined by intrinsic viscosity and virial coefficient measurements. In our laboratory, samples prepared with spectral grade benzene "as received" exhibited an apparent THETA-point near 18-degrees-C by virial coefficient and cloud point measurements. Samples which were extensively dried to remove traces of water exhibited good-solvent properties. For these samples second virial coefficients range from 1.1 x 10(-4) to 2.0 x 10(-4) cm3 mol g-2 over the range 2.5-25-degrees-C, and the Houwink-Mark-Sakurada molecular weight exponent for intrinsic viscosity was 0.58 at 11.40-degrees-C, the lowest of the reported THETA-temperatures.