Polypropylene Nanocomposites with Thermally Stable Imidazolium Modified Clay: Mechanical Modeling and Effect of Compatibilizer

Abstract

Thermally stable imidazolium modification as compared to the conventional ammonium modification is chosen to prepare polypropylene nanocomposites. Different volume fractions of organo-montmorillonite are used to generate polymer nanocomposites and the effect of the modified clay on mechanical properties is studied. The mechanical properties are also compared with Halpin—Tsai models and its modified versions to achieve better insight into the system. Addition of small amount of compatibilizer enhanced the extent of delamination of the filler. Compatibilizers are selected on the basis of their chemical nature, molecular weight, amount of grafting, and location of the polar groups. Incompatibility of the surface modification with the compatibilizer is suspected to counterbalance the delamination effect thus resulting in no change or deterioration of the oxygen permeation through the composite films. However, the tensile modulus is enhanced on addition of comaptibilizer owing to increased exfoliation, which exceeded the amount of matrix plasticization caused by the addition of the low-molecular weight compatibilizer. The compatibilizers neither affected the crystallization behavior of polymer nor the thermal behavior of the resulting composite.