Osmotic pressures of aqueous polyvinylpyrrolidone solutions

Abstract

The osmotic pressures of six well‐fractionated samples of polyvinylpyrrolidone were measured in aqueous solution in a Lucite‐block type osmometer. The molecular weights and interaction parameters were determined by employing the theory proposed by Maron for osmotic pressure. It was shown that for all of the fractions, a linear relation existed for ψ and y as predicted by the theory. This new method for expressing osmotic pressure data is compared with the more commonly used expression: It was found that the molecular weights and T2 are in satisfactory agreement. However, the value ofg was not a constant equal to 0.25, but varied with the molecular weight. The expression for the osmotic pressure given by Maron's theory appears to be an accurate and rapid method of converting osmometric data to molecular weights.

Determination of solvent/polymer interaction parameters of moderately concentrated polymer solutions by vapor pressure osmometry

“…For infinite diluted solutions, Cerny et al [31] obtained a value of 0.48 (virial expansion truncated at second virial term) using membrane osmometry. Boom et al [9] found in the concentration range of 2.5-30 wt.% a linear dependency of the interaction parameter on the concentration with parameter values between 0.475 (infinite diluted) and 0.63 (30 wt.%) at solution (FH model) using high-pressure membrane osmometry.…”

Characterisation of Hyaluronic Acid Blends Modified by Poly(N-Vinylpyrrolidone)

“…The Mark–Houwink constants for HA were obtained from the literature [ 27 ] with values of K = 3.36 × 10 −2 cm 3 /g and a = 0.79 at 25 °C in 0.1 mol/L NaCl. PVP in water had the constants of K = 3.93 × 10 −2 cm 3 /g and a = 0.59 at 30 °C [ 28 ]. All reagents, materials and chemicals used in this study were purchased from POCh (Avantor, Gliwice, Poland) and Chempur (Piekary Slaskie, Poland).…”

Kinetics of azo-initiated 1-vinyl-2-pyrrolidone polymerizations at low conversions in aqueous media

“…Capillary viscometry was conducted using Ubbelohde‐suspended level instruments with a 0.4‐mm precision bore at T (°C) = 30.00 + 0.02. The conversion of intrinsic viscosity values to viscosity average molecular weights was made using the relationship [η]O = 3.93 × 10 −4 M 10…”