Continuous melt impregnation process: materials parameters

The first step in the manufacturing of long and high fibre volume fraction of thermoplatic composite is the prepreg production with a melt impregnation process. During this process a polymeric matrix is introduced into the fibre tow. In this research an extruder equipped with a specially designed cross-head die was used for producing long and high fibre volume fraction of thermoplastic prepregs and to study the continuous melt impregnation of glass fibre roving with a polypropylene melt. A suitable relation determined from the cross-sectional area of the bundles and prepreg was selected as a proper indication of the impregnation quality. Our study shows that process and material parameters such as melt temperature and melt flow index have positive effect on the impregnation and those like line speed and melt pressure inside the cross-head die having a negative effect on fibre wetting.