Abstract:

In view of the problem of low combustion performance of polymer, two charring agents tris (2-hydroxyethyl) isocyanurate terephthalate ester (T-ester43 and T-ester45) with different degree of esterification were synthesized by using tris (2-hydrooxyethyl) isocyanurate (THEIC) and purified terephthalic acid (PTA) as raw materials. Two kinds of intumescent flame retardants (IFR43 and IFR45) were prepared by combination of T-ester and ammonium polyphosphate (APP).The preformed IFR were melt blended with four commercial thermoplastics to obtain flame retardant polymer blends. It is found that, after esterification, the decomposition temperature of charring agent increased up to 300℃ and char residue at 700 ℃ increases up to 10% from 1%. With 20% mass loading of IFR43 into PA6, PET, PLA, and PP, the char residue increased by 14.97%, 9.69%, 11.59%, and 7.25%, respectively. Correspondingly, the limiting oxygen index (LOI) value of polymers enhanced by 6%~7%. The melt drops during LOI test decreased. In addition, crystallization acceleration effect is found in the sample of PLA after addition of IFR.

Key words: intumescent flame retardant, charring agent, tris(2-hydroxyethyl) isocyanurate, polymer, combustion performance