A novel phosphorus-containing polysiloxane for fabricating high performance electronic material with excellent dielectric and thermal properties

A novel 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) functionalized hyperbranched polysiloxane (HBPEp-DOPO) with considerable epoxy groups was synthesized. The structure was characterized by Fourier transform infrared (FTIR) spectra and nuclear magnetic resonance (¹H-NMR). HBPEp-DOPO was then introduced into O,O’-diallylbisphenol A/4,4′-bismaleimidodiphenyl methane(DBMI) resin to develop modified composite with excellent dielectric and thermal properties as well as simultaneously improved comprehensive performance. The incorporation of HBPEp-DOPO not only remarkably increased the dielectric, mechanical, and thermal properties, but also obviously improved the flame retardancy. Compared with neat DBMI resin, HBPEp-DOPO/DBMI resins exhibited decreased dielectric loss with increasing the content of HBPEp-DOPO. Besides, adding 10 wt% HBPEp-DOPO could change the UL-94V of DBMI from V-2 to V-0. Moreover, HBPEp-DOPO/DBMI exhibited an improved mechanical property and thermal stability at a small addition amount. These attractive features allows the modified hyperbranched polysiloxane to have broad potential applications in cutting-edge industries, especially in electronic and electric insulating fields.