Preparation And Properties Of Hybrid Material Cyanate Ester/Epoxy Resin/Flame Retardant Containing Phosphorus-Silicon

With the improvement of electrical and electronic technology and environmental protection awareness, the widely used FR-4epoxy laminate has been unable to meet the high requirements of the environment-friendly flame retardant, low dielectric constant. The new phosphorus flame retardant DOPO and its derivatives, which is small load to environment, have received widespread attention and research. Overall, The development trend of the flame retardant is using the synergistic flame retardant combined with varieties of flame-retardant composition. And there were many reports on the effect of synergistic flame retardant was prominent, such as phosphorus-silicon and phosphorus-nitrogen.In this paper, three phosphorus-silicon flame retardants had been synthesized, which combined two flame-retardant composition in a molecule through covalent bonds and were incorporated into cyanate ester/epoxy resin(CE/EP) to study the performances of hybrid materials. The main contents of this article is as follow.A phosphorus-silicon flame retardant (P-POSS) was synthesized with DOPO, IPDI and AminopropylIsobutyl POSS, and thencharacterized by FTIR, NMR,element analysis, which was incorporatedinto EP/CE to study its effect on flame retardant properties, dielectricproperties,gel time andothers.The result showedthat,comparedwiththepure EP/CE,the hybridmaterialshavebetterflame-retardanteffect,lowerdielectric constant, longer gel time. Although the glass transitiontemperature(Tg) is reduced, the degradation temperature almost didn’tchanged. When the P-POSS content reaches7wt%, the hybrid materialhasan LOI value of32, a UL94rating V-0and22.4%char residue.Andthe dielectric constant was the lowest2.74at1MHz with5%P-POSScontent,lower0.7thanthat of pure EP/CE.Two phosphorus-silicon flame retardant (ODOPB-9007,DOPO-9007)weresynthesizedwith DOPO,ODOPBandKBE-9007,andthen characterized by FTIR, NMR and element analysis, which wereincorporated into EP/CE to study their effects on flame retardantproperties, dielectric properties, gel time and others. The two hybridsystems had similar properties due to the similar chemical structurebetweenODOPB-9007andDOPO-9007.Comparedwith the pure EP/CE,the hybrid materials have higher LOI value, lower dielectric constant,more char residue. With the flame retardant content increasing, Tg andgel time frist increased and then reduced. When the T5%reduced, thedegradation temperature almost didn’t changed. The comprehensive performance of EP/CE/ODOPB-9007was better than that ofEP/CE/DOPO-9007.