Transcrystallisation in natural fibre reinforced polypropylene

The influence of thermal conditions (recrystallisation temperature, cooling rate) as well as of different fibre treatments on the crystallisation of polypropylene was examined by using melting-microscopic analysis. The results of these investigations show that the nucleation density of untreated and MAH-grafted polypropylene treated jute fibres is higher in comparison with alkalised jute fibres because of differences in the chemical composition and physical properties of the fibre surface. With increasing recrystallisation temperature the maximum of transcrystalline layer thickness was shifted to higher crystallisation times. Experimental data of this coherence were successfully fitted by using a simple Arrhenius-type relationship. Regarding non-isothermal crystallisation, the beginning of transcrystallisation was shifted, as expected, to lower temperatures with increasing cooling rate.