Relation between Morphology and Thermo-Elastic Properties of Carbon Nanotube Polymer/Carbon Fiber Hybrid Composites

Abstract

The morphology of polyimide nanocomposite with single-walled carbon nanotubes (CNT) was considered. The effect of CNT agglomeration and twisting into a bundle was incorporated by the proposed hierarchical helical bundle model. The bundle model was used in predicting the effective thermo-elastic properties of the nanocomposite. The micromechanical analytical models were found useful in predicting the effective thermo-elastic properties of the nanocomposite. Finite element micromechanical analysis was used to calculate the residual cooling stresses inside the nanocomposite matrix with carbon fiber reinforced composites. The reduced residual stresses and transverse coefficient of thermal expansion of unidirectional lamina in the case of nanocomposite matrix were attributed to the reduced mismatch between the thermo-elastic properties of matrix and fiber. Reduction in the residual processing stresses of the hybrid composite opens the way for the use of polymeric nanocomposites as matrices in carbon fiber reinforced materials.