Synthesis and Characterization of Polyurethane Acrylate Oligomers for Electrodes Protection Adhesives of Plasma Display Panel (PDP)

Abstract

A series of polyurethane acrylate oligomers having different molar ratio of diol and diisocyanate has been synthesized from isophorone diisocyanate (IPDI), mixture of poly(ethylene-co-1,2-butylene)diol (PEBD) and 2-butyl-2-ethyl-1,3-propanediol (BEPD) and 2-hydroxyethyl methacrylate (HEMA) using dibutyl tin dilaurate (DBTL) as a catalyst. Then, the UV curable adhesives were fabricated by mixing the prepared oligomers, acrylate monomers, photo initiators, and other additives. Subsequently, the physical and mechanical properties such as coefficient of thermal expansion (CTE), elastic modulus (E'), glass transition temperature (Tg), adhesion strength and water absorption were measured. Electrochemical migration of Ag electrodes, which was resulted in the degradation of surface insulation resistance, was also investigated by measuring insulation resistance during 100 hours of 50 degrees C, 90%RH storage test.