Influence of organoclay on flexural fatigue behavior of polyamide 66/hectorite nanocomposites at laboratory condition

Abstract Polyamide 66/hectorite nanocomposites exhibit superior mechanical properties compared with pure polymers and are promising for structural applications. X‐ray diffraction results revealed reduced degree of exfoliation with increase in organoclay content. Flexural fatigue characteristics of polyamide 66/hectorite nanocomposites containing different quantities of clay content were investigated, under deflection control mode, using a custom built flexural fatigue test rig. Addition of organoclay improved the moduli of the material. An enhanced resistance to cyclic softening was noticed at high temperatures with the incorporation of organoclay. Nanocomposite samples exhibited a significant improvement in fatigue life compared with pure polymers; however, the degree of enhancement is governed by the nanostructure of organoclay in polymer matrix. The fatigue life of nanocomposite samples is strongly affected by specimen temperature and induced stress. Macroscopic fracture surfaces changed from flat featureless structure to a highly perturbed structure with increase in organoclay content. POLYM. COMPOS., 31:1977–1986, 2010. © 2010 Society of Plastics Engineers.