Evaluation and characterisation of urinary catheter coating utilising Hansen solubility parameters and FEA analysis.

Abstract

This work investigated the Hansen solubility parameters required to optimise a functional polyurethane base coat as an attachment for a lubricious polyvinyl pyrrolidone coating for polyvinyl chloride urinary catheters. Solvents included benzyl alcohol, tetrahydrofuran, acetonitrile, and cyclohexanone and blends thereof. The viscosity of the polymer–solvent compositions was characterised using Redwood No.1 viscometer. The UV cured polymer–solvent blends were fully characterised using scanning electron microscopy, differential scanning calorimetry, and digital goniometry. A finite element analysis (FEA) model of the urethra during catheterisation was also developed to illustrate the magnitude of deflection expected with the hydrophilic coating on the catheter. Based on the theoretical modelling and subsequent experimental results this demonstrated that the materials dissolved in short succession of immersion in the calculated solvent blend. Also, the various compositions of polyvinyl pyrrolidone in the solutions produced noticeable variations in coating thicknesses ranging from 8 μm to 26 μm.