Polymerization of Glycidyl Phenyl Ether with Phosphonic Acid Esters as Novel Thermally Latent Initiators

Novel phosphonic acid esters, O, O -di-1-phenylethyl phenylphosphonate ( 1 ), O, O -di- tert -butyl phenylphosphonate ( 2 ), and O, O -dicyclohexyl phenylphosphonate ( 3 ), were synthesized from phenylphosphonic dichloride and the corresponding alcohols. The phenylphosphonic esters 1 − 3 decomposed into phenylphosphonic acid and the corresponding olefins by heating at 150−170 °C. Their initiator activities were examined in the cationic polymerization of glycidyl phenyl ether (GPE). They converted GPE only 4% even at 190 °C in the absence of ZnCl 2 . In the presence of ZnCl 2 along with 1 − 3, GPE did not convert below 90 °C in the case of 1 and 2, and below 140 °C in the case of 3, but it rapidly converted to afford polyGPE with M n of 2000−7000 above those temperatures. It was found that 1 − 3 served as thermally latent initiators in the polymerization of GPE in the presence of ZnCl 2 .