PET/PEI合金的相结构模拟及性能研究

Phase structure simulation and properties of PET/PEI alloy XIU Haobo 1,GUO Chengxin 2,PENG Zhihong 2,WANG Chaosheng 3,JI Peng 3

采用聚对苯二甲酸乙二醇酯(PET)与本征阻燃材料聚醚酰亚胺(PEI)共混、熔融制备PET/PEI合金,基于Materials Studio 7.0软件构建PET/PEI分子模型,进行相结构模拟,研究PET/PEI合金的相容性,并探讨PEI含量对PET/PEI合金力学性能及阻燃性能的影响。结果表明:在任意共混比下PET/PEI合金为互不相容体系,当PEI质量分数为10%时,PET-PEI分子间C—C原子对之间的径向分布函数值为4.09,大于PEI-PEI分子间C—C原子对之间的径向分布函数值,PET/PEI合金相容性相对较好;当PEI质量分数为10%时,PET/PEI合金拉伸强度最高,为47.2 MPa;PET/PEI合金的极限氧指数(LOI)随PEI含量的增加而增大,PEI质量分数为10%时合金的LOI为24.3%,PEI质量分数为15%时合金的LOI为27.0%;PET与PEI相容性不佳,但加入PEI仍能有效改善PET/PEI合金的力学性能和阻燃性能,PEI质量分数为10%时PET/PEI合金相容性较好,力学性能好,同时阻燃性能也得到提升。

Polyethylene terephthalate/polyetherimide(PET/PEI)alloy was prepared by blending and melting PET with an intrinsic flame retardant material of PEI.A PET/PEI molecular model was established using Materials Studio 7.0 software to simulate the phase structure and study the compatibility of PET/PEI alloy.The influence of PEI content on the mechanical and flame retardant properties of PET/PEI alloy was also investigated.The results showed that PET/PEI alloy was an incompatible system at any blending ratio,and the radial distribution function value of C-C atom pairs between PET-PEI molecules was 4.09 when the PEI mass fraction was 10%,which was higher than the radial distribution function value of C-C atom pairs between PEI-PEI molecules,indicating that the compatibility of PET/PEI alloy was comparatively good;the tensile strength of PET/PEI alloy was maximized as 47.2 MPa when the mass fraction of PEI was 10%;the limit oxygen index(LOI)of PET/PEI alloy increased with the increase of PEI content,and the LOI of the alloy was 24.3%and 27.0%when the PEI mass fraction was 10%and 15%,respectively;PET and PEI did not exhibit a satisfying compatility,but the addition of PEI could still improve the mechanical properties and flame retardancy of PET/PEI alloys,and the PET/PEI alloy with 10%PEI by mass fraction possessed a good compatibility,good mechanical properties and an increasing flame retardancy.