Effect of Reactivity of Organics-Modified Montmorillonite on the Thermal and Mechanical Properties of Montmorillonite/Polyimide Nanocomposites

作者：Horng‐Long Tyan, Chyi‐Ming Leu, Kung‐Hwa Wei · 发表于：Chemistry of Materials · 年份：2000 · DOI：10.1021/cm000560x · 被引用次数：171 · 研究领域：Polymer Nanocomposites and Properties、Synthesis and properties of polymers、Silicone and Siloxane Chemistry

Montmorillonite/polyimide (3,3‘,4,4‘-benzophenone tetracarboxylic dianhydride - 4,4‘-oxydianiline, BTDA-ODA) nanocomposites displaying different morphological, thermal, and mechanical characteristics were synthesized by involving mono-, di-, and trifunctional group swelling-agent-modified montmorillonite and poly(amic acid). It was found that the dispersion of silicate layers in BTDA-ODA shifted from intercalated to exfoliated structures when the number of functional groups of the swelling agent increased to three as evidenced from X-ray diffraction and transmission electron microscopy studies. The improved morphology of the nanocomposites resulted in their enhanced mechanical and thermal properties. In particular, a 70% increase in Young's modulus, a 50% increase in the maximum stress, and a 30% reduction in the coefficients of thermal expansion for the case of BTDA-ODA nanocomposites containing 5 wt % trifunctional group swelling-agent-modified montmorillonite as compared to that of pure BTDA-ODA.