The Analysis of Synergistic Effects of Zeolites applied in Intumescent Halogen-free Flame-retardant ABS Composites

Abstract

Ammonium polyphosphate (APP) and pentaerythritol (PER) were selected to form intumescent flame-retardant (IFR) and halogen-free flame-retardant ABS/IFR/zeolite composites were prepared by melt blending. The influences of zeolite 4A, 13X on thermal behavior of mass loss, flame-retardant performance, microstructure, mechanical properties, and processability of composites were investigated. The results showed that zeolite 4A with a lower Si/Al ratio, stronger surface polarity, and lower loading not only had a better synergistic effect with IFR, which promoted the catalytic esterification of IFR, stabilized the charred residue, and made ABS/IFR composites possess higher flame-retardant performance, but also was beneficial to improving the mechanical properties and processability of composites. When the content of zeolite 4A was 1 wt%, ABS/IFR composites had better comprehensive properties. Its limiting oxygen index (LOI) value, impact strength, tensile strength, flexural strength, modulus, and melt index were 32.6%, 3.4 KJ/m², 39 MPa, 38.7 MPa, 1337 MPa, and 24.5 g/10 min, respectively.

Keywords:

• Halogen-free flame retardant ABS
• Intumescent flame retardant
• Synergistic effect
• Zeolite

ACKNOWLEDGMENT

This work was financially supported by the Natural Science Foundation of Liaoning Province (No. 20052159) and the Youth Science and Technology Foundation of Dalian, China (No. 2002114).

Notes

Note: T _onset represents the temperature at which mass loss is 5 wt%; T _p represents the temperature at the peak in DTG curve; R _max represents the loss rate at the peak in DTG curve.