Effect of Organoclay on the Morphology, Mechanical, and Thermal Properties of Polyimide/Organoclay Nanocomposite Foams

A series of polyimide (PI)/organoclay nanocomposite foams containing different contents of organoclay were prepared by the monomer in situ intercalative polymerization. The effect of organoclay on the chemical structure, morphology, mechanical, and thermal properties of the nanocomposite foams was studied. Fourier transform infrared spectra showed that the hydrogen bonds between organoclay and the polymer matrix were formed. X-ray diffraction and transmission electron microscope results indicated that the organoclay were well dispersed in the PI matrix. The compressive strength and tensile strength of the nanocomposite foams enhanced significantly, especially for the nanocomposite foam containing 4 wt% organoclay, increasing by 15% and 9%, respectively, compared with these of the neat PI foam, and the presence of the organoclay in the PI foam improved apparently the cellular structure of the nanocomposite foams. Besides, thermogravimetric analysis revealed that the addition of organoclay improved the thermal stability of the nanocomposite foams strongly, and dynamic mechanical analysis indicated that the incorporation of organoclay significantly influenced the storage modulus of the nanocomposite foams. (C) 2014 Society of Plastics Engineers