SYNTHESES AND CURED FILMS PROPERTIES OF UV-AUTOCURABLE BTDA-BASED MULTIACRYLATE RESINS

A series of UV-autocurable 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA) and benzophenone tetracarboxylic acid (BTAc) -based multiacrylate resins containing pendant glycidyl methacrylate (GMA) or glycidyl acrylate (GA) and 2-hydroxyethyl acrylate (HEA) or 2-hydroxyethyl methacrylate (HEMA) were synthesized. The effects of the acrylic functional groups, the moles of GMA, and the molar ratio of HEMA/HEA on their properties were investigated. The prepared autocurable resins are cured rapidly when exposed to UV or sunlight radiation without addition of any photoinitiator or photosensitizer and the acrylate-type resin resulted in a lower thermal curing temperature and a fast curing rate. Increasing the moles of GMA or the molar ratio of HEMA/HEA on reaction leads to a higher cross-linking density and resulted in film with a higher Young's modulus, breaking strength, and lower elongation. The methacrylate-type resin cured to a very hard, but brittle film with a higher Young's modulus and lower elongation. However, the acrylate-type resin cured to a hard tough film with a lower Young's modulus and higher elongation. The cured methacrylate-type resin results in a lower weight loss at temperature below 300-degrees-C due to a higher cross-linking density and lower residual weight percent at 600-degrees-C due to the lower percent of benzene rings in the resin. The film properties of the resins coated on steel plates were also investigated. (C) 1994 John Wiley & Sons, Inc.