Crystallization of R-BAPB type polyimide modified by carbon nano-particles

A new semicrystalline polyimide, based on 1,3-bis-(3,3′,4,4′-dicarboxyphenoxy)benzene (R) and 4,4′-bis-(4-aminophenoxy)biphenyl (BAPB), was modified by carbon nanotubes and other carbon type fillers. This R-BAPB type polyimide, with a molecular weight Mw = 30,000 g/mol has a low melting temperature of 320 °C and a melt viscosity of about 1000 Pa s at 340 °C that gives the possibility to mix it with carbon particles by using solvent- and melt-based mixing. This study, based on calorimetric and rheological measurements, presents the nucleating effect on the polyimide of four types of carbon fillers, namely, carbon nanotubes, vapor grown carbon fibers and regular and graphitized carbon black. The strongest nucleating effect is observed for fillers with highly ordered graphitic structure, for which the highest degree of crystallinity of the polyimide matrix can be regenerated.