In this work, the influence of curing temperature on microstructures of isobutylene-isopropene rubber/ clay nanocomposites (IIRCNs) prepared by melt compounding was characterized using wide-angle X-ray diffraction and TEM. The gas barrier and tensile properties of IIRCN cured under different temperature were examined. The results reveal that high pressure, curing reactions, and reactions of amine intercalants with curing agents together play important roles on determining the final microstructures of cured IIRCNs. Changing curing temperature would dramatically alter intercalated structure, dispersion homogeneity, filler-rubber interaction strength, and crosslinking density of obtained IIRCN, resulting in great difference in final properties. Finally some suggestions for the preparation of successful RCNs were proposed. (c) 2008 Wiley Periodicals, Inc.