Characterization of physicochemical properties of perfluorodecanoic acid–polyquaternium cellulose hydrogel

We investigated the nature and stability of the interactions established between polyquaternium (PQ10) and perfluorodecanoic acid (PFDA) in terms of different variables such as composition, ionic strength, pH and temperature. The PQ10–PFDA complex formation is interpreted in view of electrostatic associations between carboxylic and quaternary amino group. The properties of the systems were characterized by rheology analysis. The adhesive properties of complex were also assessed. One of the macroscopic features of the new material formed in solution was the increase in viscosity from 6 Pa s for 1% PQ10 (MW 1.7 × 106 g mol−1) to about 1000 Pa s by the addition of enough PFDA to reach 1:0.5 ammonium:carboxylic group molar ratio. At this proportion, PQ10 and PFDA form a network structure with a maximum viscosity and storage modulus. This maximum coincides with an increased mucoadhesive work.