Title
Viscosity of hydroxypropyl cellulose solutions in the presence of poly(N-vinylpyrrolidone)
Authors
MARIA BERCEA, ALEXANDRA LUPU, IOANA-ALEXANDRA PLUGARIU, LUIZA MADALINA GRADINARU and PATRICK NAVARD

Received Dedicated to the memory of Acad. Bogdan C. Simionescu (1948 – 2024)
Published Volume 59 Issue 7-8 July-August
Keywords hydroxypropyl cellulose, poly(N-vinylpyrrolidone), aqueous solution, viscosity, intermolecular interactions

Abstract
The paper reports viscosity data for aqueous solutions of hydroxypropyl cellulose (HPC) in the presence of poly(N vinylpyrrolidone) (PVP) in dilute, semidilute and concentrated regimes. The two polymers are miscible over the entire range of composition. In dilute solution, mixed isolated coils with more extended chain conformation are formed and binary polymer-polymer interactions are favored when a small amount of PVP is added to HPC solutions. The viscosity increases in semidilute and concentrated regimes due to chain entanglements and a pronounced synergistic effect was observed upon the addition of a small amount of PVP to the HPC isotropic solution. The intermolecular hydrogen bonding between the hydroxyl groups of HPC and the carbonyl groups of PVP influences the overall flow behavior.