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Abstract

DMA spectra were taken from tensile loaded neat and glass-fiber mat- reinforced polypropylene (GMT-PP) with different reinforcement fractions (V_f ). Reliable data were achieved by using rectangular specimens of proper dimension, i.e., having a clamped surface of 60 x 15 mm². It was established that the β- or T_g -transition of PP re mains unaffected by adding GF mat. This was attributed to the fact that GF does not inter fere with the crystallization. The α-transition, linked to the crystalline morphology, disap peared by GF mat incorporation. It is reasonable that the GF mat, wetted by the matrix, overtakes the control in the rubbery region (between T_g and melting temperature, T_m ) for the deformability from the matrix in the unreinforced state. The complex dynamic tensile modulus (E*) of the GMT-PP's changed linearly with V_f for various temperatures, which allows a reliable estimation of the stiffness for different GMT-PP types.

Keywords

dynamic mechanical analysis DMA elastic-modulus glass mat- reinforced thermoplastics GMT mechanical relaxation polypropylene.

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Dynamic Mechanical Analysis of Glass Mat-Reinforced Polypropylene (GMT-PP)

Abstract

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References