Pressure-sensitive adhesives (PSAs) are those sticky materials that can stick to various substrates under light pressure at room temperature. PSAs are widely used for production of tapes such as duct tape and package tapes, labels, stamps, post-it® notes and many other products. At present, PSAs are mainly derived from petrochemical-based polymers such as polyacrylates. Petrochemicals are not renewable. Most of existing tapes and labels made with petrochemical-based PSAs are produced in two major steps: 1) production of PSA polymers through an emulsion or solution polymerization process, 2) coating of the PSA emulsion or PSA solution in an organic solvent onto films or paper. The PSA-coated film or paper then goes through a heated oven for evaporation of water or an organic solvent, which is an energy-consuming process. Organic solvents and other toxic chemicals are typically required in the production and application of petrochemical-based PSAs. Scientists at Oregon State University have recently invented novel PSAs that are based on vegetable oils, more specifically epoxidized fatty acids. The epoxidized fatty acids are directly coated onto release liners without use of water or any organic solvent, cured in a heated oven, and then transferred to paper or plastic films to form labels and tapes. The process of making tapes and labels from this new PSA eliminates the process of coating a PSA emulsion or solution and subsequent evaporation of water or an organic solvent, which requires much less energy than processes of making tapes and labels with petrochemical-based PSAs. No volatile organic compounds are released in the entire process. The process is simple and very environmentally friendly. The new PSAs are cost-competitive to those petrochemical-based PSAs. Petrochemical-based PSAs are not readily biodegradable after their useful lives, thus resulting in environmental pollution. The new PSA is based on fatty acid, and is expected to be easily biodegradable. In this project, we will build a pilot scale of a prototype process for making labels and tapes from epoxidized fatty acids and investigate if the process can be operated efficiently and cost-competitively in a commercially viable production speed.
