Title: The Identification and Screening of Lower Toxicity Solvents for Contact Adhesives
Researchers: Christopher Hansen, Gregory Morose, Catherine Barry
Sponsors: Toxic Use Reduction Institute at UMass Lowell
Collaborators: ITW Polymer Sealants (Rockland, MA), Keith Begin, Michael Atwater
Description: Contact adhesives, which bond to themselves upon contact, frequently contain hazardous air pollutants (HAPs) and volatile organic compounds (VOCs) that detrimentally impact human health and the environment. Commercial formulations containing rubbers and resins impose demanding requirements that balance solubility, viscosity, evaporation, color, odor, and cost. Solvent compositions that contain safer solvent alternatives to the hazardous air pollutants toluene and hexane, and which retain the solubility of rubbers and resins in contact adhesives is predicted with Hansen Solubility Parameters (HSP). A database of solvents selected based on health and environmental data from those available in the Hansen Solubility Parameters in Practice (HSPiP) software was used to identify binary and ternary solvent blends based on solubility, evaporation rate, and density. Promising new solvent blend candidates were experimentally tested for solubility, evaporation rate, cold temperature stability, adhesive application and edge bond strength and their performance compared to commercial formulations.