Synergistic antioxidant effect of phosphonite P-EPQ and hindered phenol in polypropylene
Hydrogen peroxide clearance experiments and thermogravimetric analysis were conducted to compare the anti-oxidant activity and thermal stability of tetrakis(2,4-di-tert-butylphenyl)4,4′-biphenylene diphosphonate(Hostanox P-EPQ)and tris(2,4-di-tert-butylphenyl)phosphite(Irgafos 168).The results demonstrated that due to its higher phos-phorus content and unique P—C bond in the structure,P-EPQ exhibited superior antioxidant performance and thermal stability.Furthermore,hindered phenolic antioxidants Irganox 1010 and Irganox 1076 were selected to be compounded with P-EPQ to investigate their synergistic antioxidant effects in isotactic polypropylene(iPP).The comparison of chang-es in melt volume flow rate(MVR)and yellowing index(YI)during multiple extrusion,as well as the oxidation induc-tion period(OIT)in oxygen atmosphere of iPP stabilized by compound antioxidants indicated that the combination of an-tioxidant 1010 and P-EPQ exhibits a significant synergistic effect.When the mass ratio of 1010 to P-EPQ was 6/4,the stabilized iPP had the optimal overall stability performance.At this stage,the MVR and YI of antioxidant-modified sam-ple after the fifth extrusion were only 19.8%and 79.9%of pure iPP,while the OIT at 180℃significantly increased from 0.8 min to 74.8 min.
国家科技期刊平台
NSTL
万方数据
