An experimental study of impregnation conditions on glass fiber reinforced thermoplastic polyester elastomer composites

A study was conducted on the effects of variables such as impregnation and cooling conditions on bending properties of glass fiber reinforced thermoplastic elastomer composites. The impregnation time was varied between 5 and 30 minutes and samples were cooled under rapid and gradual cooling conditions. A bending test was carried out on samples with different fiber orientations. Detailed evaluations on thermal properties and morphology were obtained using a differential scanning calorimeter (DSC), a scanning electron microscope (SEM) and an optical microscope. Impregnation of matrix resin into glass fiber was completed before 30 minutes impregnation time. Bending properties were found to increase with increasing impregnation time. SEM micrographs revealed poor adhesion between the matrix resin and glass fiber. This was attributed to the structure of the thermoplastic polyester elastomer. Thermal properties such as melting and glass transition temperatures were not affected by the cooling conditions. The degree of crystallinity by rapid cooling was less than by gradual cooling.