Influences of material and process parameters on the properties of pultruded glass fiber/polypropylene composites

摘要

In a series of experiments, optimum processing windows (preheating temperature, heated die temperature, pulling speed) for pultrusion of rectangular profiles out of commingled glass fiber/polypropylene (GF/PP) yarn with different glass fiber volume fractions and pre-impregnated GF/PP tapes were determined. Mechanical properties such as flexural modulus, flexural strength and shear strength were determined. Mechanical properties such as flexural modulus, flexural strength and shear strength were measured as a basis for comparison to studies of other investigators and as data for establishing process models. As a quality criterion, a shear strength of 80 percent of the maximum achievable shear strength was shosen. Furthermore, the influence of processing parameters on the void content of the pultruded beams was determined and compared to values predicted by a model approach. The maximum allowable void content was set in the model as 2 percent. It resulted in a surve for the minimum processing time at a given heated die pressure. The results obtained were in good agreement with experimental data.