MC尼龙和MC尼龙/纳米ZnO复合材料晶面间距的膨胀系数和收缩系数

Expansion and Shrinkage Coefficient of Crystal Face Distance of the MC Nylon and MC Nylon/ZnO Nanocomposites

采用原位聚合反应制备铸型(MC)尼龙6/纳米ZnO复合材料,并用动态高温X射线衍射(XRD)法对合成的MC尼龙/纳米ZnO复合材料进行研究,考察其在升温和降温过程中α1和α2晶面间距的变化、结晶结构的热稳定性。结果表明,随着温度的升高,MC尼龙的α1(200)和α2(002+202)晶面分别发生了收缩和膨胀,降温过程中分别为膨胀和收缩。纯MC尼龙在升温过程中晶面的线膨胀系数为ααT1=-1.45515×10-4℃-1、ααT2=4.03985×10-4℃-1;降温过程中晶面的线收缩系数为βαT1=-2.53341×10-4℃-1、βαT2=3.77188×10-4℃-1。MC尼龙/纳米ZnO复合材料在升温过程中α1和α2晶面的线膨胀系数为ααT1=-1.45984×10-4℃-1、ααT2=3.18063×10-4℃-1;降温过程中α1和α2晶面的线收缩系数为βαT1=-1.23801×10-4℃-1、βαT2=2.98470×10-4℃-1。可见,纳米ZnO的加入,使MC尼龙对温度的敏感度降低,提高了MC尼龙的热稳定性。

MC nylon/ZnO nanocomposite was prepared by in-situ polymerization and analyzed by the dynamic high temperature X-ray diffraction（XRD）.Changes of interplanar （crystal） spacing between α1（200） and α2（002＋202） and thermal stability of crystal structure in war ming and cooling process were in research.The results show that α1 and α2 of MC nylon shrunk and expanded respectively,as the temperature increased and reversed as the temperature decreased.The thermal expansion coefficient of the lattice planes of MC nylon is αα1T=-1.45515×10-4℃-1 and αα2T=4.03985×10-4℃-1 and the shrinkage coefficient of the lattice planes of MC nylon is βα1T=-2.53341×10-4℃1 and βα2T=3.77188×10-4℃-1.The thermal expansion coefficients of MC nylon/ZnO nanocomposites is αα1T=-1.45984×10-4℃-1 and αα2T=3.18063×10-4℃-1 and the shrinkage coefficient of the lattice planes of MC nylon/ZnO nanocomposites is βα1T=-1.23801×10-4℃-1 and βα2T=2.98470×104℃-1.It can be concluded that the addition of nano-ZnO reduces the sensitivity of MC nylon to the temperature,and enhances the thermal stability of MC nylon.