Dynamic mechanical properties of short sisal fibre reinforced polypropylene composites

The dynamic mechanical properties of short sisal fibre reinforced polypropylene composites containing both untreated and treated fibres have been studied with reference to fibre loading, fibre length, chemical treatments, frequency and temperature. By the incorporation of short sisal fibre into polypropylene, the storage moduli (E')and loss moduli (E) have been found to be increasing whereas the mechanical loss factor (tan delta) decreasing. The storage modulus decreases with increase in temperature. The treated fibre composites show better properties compared to untreated system. The Arrhenius relationship has been used to calculate the activation energy for the glass transition. The use and limitations of various theoretical equations to predict the tan delta and storage modulus of the fibre reinforced plastic composites have been discussed. Cole-Cole analysis has been carried out to understand the phase behaviour of the composite samples. A master curve for the modulus of the blend is drawn by applying the time-temperature super position principle. (C) 2003 Published by Elsevier Science Ltd.