EFFECT OF POLYPROPYLENE FIBER ON THE TENSILE PROPERTIES AND MICROSTRUCTURAL BEHAVIOR OF POLYESTER COMPOSITES

In this study, polypropylene (PP) was added to polyester material, which is widely used in theindustry and can also be utilized as a matrix material, in chopped weight fractions of 0%, 0.25%,0.5%, and 0.75% to improve its mechanical performance. Tensile tests were conducted todetermine the optimal additive ratio. The experimental results revealed that the best additiveratio was 0.5% by weight of PP in the polyester material. This ratio formed a good interfacewith the polyester matrix, thereby enhancing its tensile strength. On the other hand, the 0.75%additive ratio caused significant agglomeration issues in the polyester material, leading to areduction in its mechanical strength.Experimental analyses were extended by obtaining microscopic images after the tensile tests,and damage analyses were performed based on these images. The microscopy results showed adetailed examination of the distribution of chopped PP additives within the polyester matrix. Itwas determined that the most homogeneous structure was achieved in polyester compositeswith 0.5% by weight PP.This study demonstrates that low-cost and lightweight additive materials like polypropylenecan enhance the performance of thermoplastic matrices such as polyester when used inappropriate ratios. However, it highlights that microstructural issues like agglomerationobserved at higher additive ratios can adversely affect material performance.