Synthesis and characterization of phosphorus-containing methacrylate-baseddifunctional crosslinkers and their use in UV-curable resin systems

Two new phosphorus-containing methacrylate-based difunctional crosslinking agents [bis(4-(2-methacryloyloxy)ethyl carboxyl)phenyl phosphine oxide (BEP PPO) and bis(4-(2-methacryloyloxy)ethylcarbonylaminophenyl)phenyl phosphine oxide (BUPPPO)], which can be good candidates for W-curable coating applic ations, were synthesized by reacting either a phosphorus-containing diisocy anate [bis(4-isocyanatophenyl)phenyl phosphine oxide] or a phosphorus-conta ining diacid chloride [bis(4-chloroformylphenyl)phenyl phosphine oxide] wit h hydroxyethyl methacrylate. The structures of the monomers thus obtained w ere characterized by FTIR, mass, and H-1-NMR spectroscopies. The contents o f the new crosslinking agents in the UV-cured polymeric films were varied b etween 10 and 30% by weight. Mechanical, physical, and thermal characteriza tions of the W-cured films were investigated. An increase in crosslinking a gent content caused an increse in mechanical properties. Films containing B UPPPO had higher tensile strength values compared to the films containing B EPPPO. Thermogravimetric analysis of phosphorus-containing crosslinking age nts revealed that incorporating phosphorus into the structure resulted in a high char yield up to 24.5% at 600 degrees C. Water absorption values of U V-cured films were also affected by the amount and type of crosslinking age nt. (C) 1999 John Wiley & Sons, Inc.