| Abstract: | Glass laminates have been readily obtained by photocuring at ambient temperature of an acrylic adhesive consisting either of a liquid resin or a solid thermoplastic polymer. The light-induced polymerization process was followed by real-time infrared spectroscopy. Close to 100% conversion was reached within a few seconds of exposure, by taking as the photoinitiator an α-hydroxy alkylphenone or an aryl phosphine oxide. A liquid formulation containing an aliphatic polyurethane–acrylate oligomer, acrylic acid, and butyl acrylate gives the best performance in terms of reactivity, adhesion, impact resistance, and transparency. The impact resistance was further increased by introducing a polycarbonate core between the two glass plates. The solid thermoplastic polymer was obtained either by casting from a solution containing an aliphatic polyurethane, an acrylate oligomer, and the photoinitiator or by mixing these compounds in the molten state and further extrusion. The glass assembly was heated above the softening temperature (80°C) under a 1 MPa pressure and cured by a 1 min exposure to UV radiation to give a strongly adhesive laminate showing good transparency and long term weatherability. © 1995 John Wiley & Sons, Inc. |
