Study Of The Effects Of PPTA/EG/APP On Mechanical And Flame Retardant Properties Of ABS Resin

In this paper, PPTA/EG/APP as halogen-free and nontoxic intumescent flame retardant was used to enhance the flame retardancy of ABS resin by melt blending method. On the basis of ABS that reinforced by inorganic filler CaCO3/SiO2, EG/APP intumescent flame retardant was added to ABS with other additives to prepare flame retardant ABS/EG/APP composites. In order to solve the worsening problem of ABS/EG/APP composites mechanical properties, PPTA short fiber was added into intumescent flame retardant to prepare ABS/PPTA/EG/APP composites. The mechanical properties, flame retardancy, thermal stability, combustion behavior and fracture surface were investigated by the tests and characterizations such as mechanical properties tests, limited oxygen index(LOI), vertical firing(UL-94), thermogravimetric analysis(TG)and scanning electron microscopy(SEM).The results showed that when CaCO3/SiO2 dosage was 10wt%, and CaCO3/SiO2 mass ratio was 1/1, ABS/CaCO3/SiO2 composites presented great mechanical properties. In the experiment, CaCO3 and SiO2 showed a good compatibility with ABS. Compared to the ABS/CaCO3/SiO2 composites, when the addition of flame retardant EG/APP was 15wt%, its thermal stability increased. Under such conditions, the composites showed the best thermal stability and flame retardancy when the EG/APP mass ratio was 3/1. This part of the work kept the EG/APP mass ratio on 3/1, and kept the flame retardants PPTA/EG/APP dosage on 15wt%, the ABS/PPTA/EG/APP composites showed better mechanical properties, but the thermal stability got worse. When the PPTA addition was more than 7.5wt%, the mechanical properties greatly improved. And when the PPTA addition was less than 7.5wt%, the best dosage was 5wt% when it showed a great mechanical property. What’s more, When the amount of PPTA was more than 3.75wt%, its flame retardancy showed a sharp decline. Taking into the economical technical indicators account, the content of PPTA could be controlled in the range of 3wt%~5wt% in the composites.