| In this paper, the MMT was modified by different intercalation reagents. Mole ratio of 1:1.1 MMT to cetyl trimethyl ammonium chloride was used, at 80℃for 2h, the interlayer distance of organic MMT increased from 1.26nm to 2.26nm characterized by XRD. The coupling agent was used to modify the surface and edge of MMT to enhance the compatibility of MMT and polymer.PET was prepared through direct-esterification process, and the PET/I-MMT, PET/CEPP, PET/I-C-MMT/CEPP, PET/I-C-MMT/ PSPP were synthesized by adding reactive or additive flame retardant before esterification, and organic MMT was added before polycondensation.The viscidity of the PET/I-MMT, PET/CEPP, PET/I-C-MMT/CEPP and PET/I-C-MMT/ PSPP were lower than that of PET, especially PET/I-C-MMT/ PSPP. The structure of modified PET was characterized by FT-IR and TEM. It showed that CEPP and MMT were incorporated into polyester and the addition of coupling agent can decrease the aggregation of MMT.Thermal stability properties of modified PET were analyzed by TG, It indicated that Tmax and the heat-decomposed remainders of PET/I-C-MMT/CEPP and PET/I-C-MMT/ PSPP were high. Kissinger method was used to analysis the thermal degradation kinetic behavior of modified PET, and it revealed that the degradation activation energies of PET/I-C-MMT/CEPP and PET/I-C-MMT/ PSPP were higher than that of PET .The flame retardancy of modified PET was investigated by Cone Calorimeter. It showed that the HRR, THR and EHC of the PET containing MMT and flame retardant decreased obviously. MMT and flame retardant CEPP have good flame retardancy for PET.Non-isothermal crystallization kinetics of the polymers were investigated by DSC. It found that the MMT could act as an efficient nucleating agent. The crystallization of PET/MMT composites decreased because MMT may cause the formation of physical crosslink points so that the crystallization decreased. And the incorporation of CEPP and PSPP could decrease the crystallization of modified PET. |
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