Synthesis and characterization of copolymers of poly(m-xylylene adipamide) and poly(ethylene terephthalate) oligomers by melt copolycondensation

Abstract

Abstract: Poly(m-xylylene adipamide)/poly(ethylene terephthalate) (MXD6/PET) copolymers are synthesized by melt copolycondensation with 1-5 wt% low molecular weight PET oligomers into the MXD6 oligomers at 260℃. FR-IR and ¹H NMR analysis results indicate that the interchange reaction has occurred between MXD6 oligomers and PET oligomers. The thermal behavior of copolymers shows that the melting temperature of MXD6/PET copolymers decreases with the increasing of amount of PET oligomers, while the crystallization temperature accordingly increases. And the equilibrium temperature T_m⁰ is evaluated to be 251.8℃ for the copolymers with 5 wt% PET oligomer adding, which is very close to that of neat MXD6. The tensile and impact strength of MXD6/PET copolymers are significantly improved than that of pure MXD6 by mechanical properties test, and the microfibril structure in the impact fracture sample's surface reveals the feature of ductile fracture.

Key words: Polymerization, Poly(m-xylylene adipamide), Poly(ethylene terephthalate), Crystallization, Mechanical properties

摘要： Poly(m-xylylene adipamide)/poly(ethylene terephthalate) (MXD6/PET) copolymers are synthesized by melt copolycondensation with 1-5 wt% low molecular weight PET oligomers into the MXD6 oligomers at 260℃. FR-IR and ¹H NMR analysis results indicate that the interchange reaction has occurred between MXD6 oligomers and PET oligomers. The thermal behavior of copolymers shows that the melting temperature of MXD6/PET copolymers decreases with the increasing of amount of PET oligomers, while the crystallization temperature accordingly increases. And the equilibrium temperature T_m⁰ is evaluated to be 251.8℃ for the copolymers with 5 wt% PET oligomer adding, which is very close to that of neat MXD6. The tensile and impact strength of MXD6/PET copolymers are significantly improved than that of pure MXD6 by mechanical properties test, and the microfibril structure in the impact fracture sample's surface reveals the feature of ductile fracture.

关键词: Polymerization, Poly(m-xylylene adipamide), Poly(ethylene terephthalate), Crystallization, Mechanical properties

CLC Number:

10.1016/j.cjche.2016.04.003

Fenglei Bi, Jianqiang Shao, Zhenhao Xi, Ling Zhao, Di Liu. Synthesis and characterization of copolymers of poly(m-xylylene adipamide) and poly(ethylene terephthalate) oligomers by melt copolycondensation[J]. , 2016, 24(9): 1290-1297.

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