Preparation and Properties of Hairy-Rod Molecular Composites

Abstract

Molecular composites are polymer blends, in which rigid rod-like “fiber” polymers are molecularly dispersed in flexible polymer matrix^1,2. To obtain excellent mechanical properties of the composites, fiber polymers must be so isotropically dispersed in the blend system that no phase separation can be observed^3,4. Once phase separation has taken place, the molecular composite transforms to a macroscopic composite, and this phase separation is a serious problem in most of molecular composites. In polymer systems containing rigid-rod polymers a phase separation is particularly facile to occurr, since between the rigid backbones a strong van der Waals attraction is present to form a separate phase. To overcome this phase separation problem a number of novel methods has been introduced for making molecular composites with satisfactory properties.