The Use of the Hansen Solubility Parameters in the Selection of Protective Polymeric Materials Resistant to Chemicals

This article focuses on solubility of chemicals on polymeric materials as an approach for selecting the best protective materials. The Hansen three-dimensional solubility parameters (HSP) were used to obtaining the solubility parameters of five of the most used polymer materials from swelling tests with forty chemicals covering a broad spectrum of HSP values. The approach considers that for chemical substances that are soluble in a polymer protective material, this material will not be resistant. Inversely, for polymer materials for which chemical substances are not soluble, the material will be resistant. Based on the experimental data, the Hansen HSPiP software was used to calculate the solubility parameters (the center of the sphere) and radii, R, of the polymer spheres for Nitrile, Neoprene, Natural Rubber, Viton and Butyl Rubber glove materials. Based on the calculated HSP values for the glove materials, the differences with the HSP values (dissimilarity A value following the Hansen approach) for more 1 200 chemical solvents were calculated. The Hansen solubility approach states that for chemicals where the solubility parameter distance (A) of a given chemical to the center of the polymer sphere is higher than the R value, A/R >1, the material will be resistant and inversely, for A/R < 1 the material will be not resistant. In this study, a new approach that considers the Hansen Sphere with a modified R was developed. An algorithm that compared the predicted values with close to nine hundred experimental data from the literature, allows defining for each material a zone of uncertainty with minimum and maximum R values. A Software (ProtecPo) was developed that allows the selection of the best glove materials avoiding a dangerous “trial and errors” approach. In any case this software is a substitute of permeation tests to determine the level of chemical resistance to a chemical or mixtures of chemicals.