Development of a polyurethane sealing gasket with excellent sealing and opening properties

Alternative materials to replace the currently used poly(vinyl chloride) (PVC) plastisols as sealing gaskets for use in wide-mouth glass jars have been desired. In this study, we propose a novel urethane-based polymer as a better replacement for PVC plastisols. This polymer was prepared by reacting a diol with a molecular weight (MW) of 1000 g mol -1, a triol with an MW of 500 g mol -1 and an aliphatic diisocyanate adduct with MW of 430 g mol -1. When additives, such as hollow particles as a blowing agent and lubricants, were incorporated into this urethane polymer, the resulting material exhibited a rubbery plateau with a low modulus over a wide temperature range, from a temperature <0 °C to a temperature >100 °C. These properties favorably support this material for use as a sealing gasket owing to its remarkable sealing and opening characteristics.