A new type of dialkyl group hypophosphite flame retardant was synthesized in this paper. The dicyclohexenyl sodium hypophosphite was first prepared via cyclohexene and sodium hypophosphite

and then reacted in free radical initiator and normal pressure conditions with ethanol as the solvent. Dicyclohexenyl aluminum hypophosphite (DCAH) was obtained by adding aluminum sulfate. Molecular structures were characterized by FT-IR. Phosphorus and carbon element contents were measured by energy dispersive X-ray spectroscope. Product thermostability was analyzed via thermogravimetric analyzer. Flame retardant properties were investigated by adding DCAH to polyamide (PA); limiting oxygen index (LOI) and vertical burning were determined. The influences of initiator species

initiator dosage

temperature

and reaction time on target product yield were discussed

and synthesis condition was optimized. The effect of DCAH additive content was also studied. Benzoperoxide was the best initiator

and the optimum dosage was 5%. The product could yield up to 84% when reacted for 10 h at 85℃. LOI was 34. 1 %

and flame class was FV-0

whereas 12% DCAH was added to PA material.