CRYSTALLIZATION OF CARBON-FIBER REINFORCED POLYPROPYLENE

Polypropylene (PP) was compounded with carbon fibre of various contents (0, 5, 10, 15, 20 vol%) using a single and a twin screw extruder. The influence of both the carbon fibre content and the compounding method on the thermal behaviour and characteristics of crystallization was studied using differential scanning calorimetry (DSC), polarizing optical microscopy and scanning electron microscopy (SEM). Melting and crystallization temperatures increased with the amount of carbon fibre. Isothermal crystallization was observed using DSC and it was found that crystallization was accelerated by the presence of carbon fibres. Using polarizing optical microscopy, it was found that the nucleation of polypropylene started at the crossing point of two or more fibres. © 1990 Chapman and Hall Ltd.