Synthesis and Characterization of Epoxy Resin Flame
Retardant
Abstract
A novel phosphorus-containing hydroxyl benzoaldehyde (DOPO-HB) from 9,10-dihydro-9-oxa-10– phosphaphenanthrene -10-oxide (DOPO) and 4-hydroxyl benzoaldehyde was obtained via simple addition reactions.The synthesis conditions of DOPO-HB were also optimized A novel phosphorous -containing flame retardants 10-(2,5-dicarbonylpropyl) 9,10-dihydro-9-oxa-10-phospha- phenanthrene-10- oxide (DOPO-ITA) was synthesized using 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (DOPO) and itaconic acid(ITA) as starting materials.The chemical structure of the obtained DOPO-HB and DOPO-ITA were characterized with FTIR, 1H and 31P NMR and elemental analysis. The DOPO-HB, with multi-phenol groups in the molecular chain, was used as a poly functional curing agent for epoxies. The activity and activation energies of the DOPO-HB curing reactions with epoxies were investigated with differential scanning calorimetry (DSC). The thermal properties and thermal degradation behaviors of the DOPO-HB-cured epoxy resins were also studied with DSC and thermo gravimetric analysis(TGA). The paper also focuses on the solubility of DOPO-HB in different solvents with the temperature trend, the results show that, the solubility of DOPO-HB in benzene, toluene and xylene, and water increases with the temperature rising. Moreover, the benzene> xylene> toluene> Water