Reasearch On Novel Organic Hybrid Hexagonal Boron Nitride And High Performance Bismaleimide Resin

Bismaleimide resin is a typical high performance thermosetting resin, but its thermalconductivity and flame retardancy are still need to be improved to meet the needs ofcutting-edge-industry applications. Numerous studies have shown that the development ofmultifunctional material is the key to increase the flame retardancy and high thermalconductivity property of polymers. However, conventional flame retardants do not havehigh thermal conductivity. Therefore, it is of great interesting to make progress on thisissue, and this is the subject of this thesis.Based on the molecular design of novel organic hybridized hexagonal boron nitride(hBN), a novel multifunctional material, organic hybridized hexagonal boron nitride flameretardant (CPBN) was synthesized, which can combine the high thermal conductivity ofhBN and the excellent flame retardancy, surface activity of hexachlorocyclotriphosphazene(HCCP). Our research work includes following two parts.First, hexagonal boron nitride/bismaleimide (BD) composites (hBN/BD) wereprepared; then the effects of hBN on integrated properties of hBN/BD composite wereintensively evaluated. The results demonstrate that hBN can not only improve the thermalproperties (thermal conductivity, thermal expansion and thermal stability) of the BD resin,but also effectively improves the flame retardancy of the BD resin.Second, in order to overcome the poor compatibility between hBN and BD resin,HCCP was grafted on hBN, and a novel organic hybridized multifunctional flame retardant(CPBN) was successfully synthesized. Compared with hBN, CPBN has a large amount offunctional groups, and these groups show high activity, which provides a very favorablesecurity for CPBN to get a good dispersion and interfacial adhesion with BD resin. A seriesof CPBN/BD composite were prepared, and their curing behavior, thermal properties,flame retardancy and mechanism were intensively studied. It is found that the CPBN/BDcomposites exhibit good integrated performances, especially excellent flame retardancy.This is attributed to the unique hybrid structure of CPBN that changes the burning behavior and flame retardancy mechanism.