A novel intumnescent flame melamine salt of dipentaerythriol phosphate (MDP)

was prepared from dipentaerythritol (DPE) polyphosphoric acid

and melamine. The flammability

combustion behavior

and thermal degradation and stability of PP-MDP were characterized. When MDP loading was 20 wt%

LOI values of the composites reached up to 27%

and UL94 rating

V-2. PP-MDP containing 1 wt% Cu-ZSM-5 presented the highest LOI value of 30.5% and UL94 rating

V-0

and released lest heat during cone test. TG data showed that the thermal degradation of PP was improved by the addition of MDP. While the loading of ZSM-5 was 1 wt% or higher

the main weight loss delayed with 50oC

and 80oC

compared with PP and PP-MDP respectively. The appropriate loading Cu-ZSM-5 made PP-MDP possess higher thermal oxidative stability. By SEM

the formation of a dense and thick char layer was observed on the char layer of PP-MDP-containing Cu-ZSM-5

responsible for high flame retardancy. So

the synergistic flame retardancy effects of MDP and Cu-ZSM-5 on PP existed. The mechanism of synergistic effect of Cu-ZSM-5 zeolite on flame retarded PP by MDP was discussed.