Synthesis of a novel spiro orthocarbonate and its application in epoxy resins

A novel spiroorthocarbonate( DSOC) was synthesized through the reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide( DOPO),2,3-epoxy-1-propanol,dibutyltin oxide and carbon disulfide. The structure of DSOC was confirmed by FT-IR,1H NMR spectra and elemental analysis. Then it used as anti-shrinkage additives and flame retardant in the cationic polymerization of epoxy resins( E-51). It was found that shrinkage decreased with increased concentration of DSOC. At 10wt% of DSOC,not only the shrinkage of epoxy resins was eliminated,but a small level of volume expansion was also achieved. The flame retardancy and mechanical properties of modified epoxy resins were also investigated.