Development of polymer matrix composites reinforced with natural fibers for automotive industries

Recently, researchs on the development of the composite materials have focused on the development of alternative natural additives, instead of the synthetic materials due to easy access and low cost of natural resources. The use of plant fibers in the production of fiber reinforced polymer matrix composite materials is an environmentally friendly and sustainable process. The use of cellulose fibers from natural plants as an alternative to synthetic fibers as an additive in the production of polymer matrix composite materials has increased in many industrial fields due to their low weight, low cost, non-destructive properties for production equipments and good mechanical strength. The aim of the present study is to develop a new composite material with improved mechanical properties by using polymers such as polystyrene (PS) and polyvinyl chloride (PVC) which are used in the structure of many automobile components in the automotive industry with natural plant fibers. In this study, waste artichoke stalks were used to obtain natural cellulose fibers. In the first stage of the study, the structural composition of the artichoke stalks was determined and microcrystalline cellulose (MCC) was obtained. The chemical structure, crystal structure and morphological structure of the obtained MCC were examined by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) method and scanning electron microscopy (SEM), respectively. Based on the SEM micrographs, MCC exhibits an ordered structure consisting of fibers with diameter in micro level and oriented along an axis. Then, MCC reinforced polymer matrix composites were produced by solution casting method. The chemical interactions between the constituents of the composite materials were analyzed by FTIR. The effects of PVC, glycerol and MCC additives and also the additive ratios on the mechanical properties, thermal decomposition behavior, morphological structures and dielectric properties of the PS matrix were investigated by tensile tests, thermogravimetric analysis (TGA), SEM and dielectric constant measurements, respectively. According to the tensile tests, it was determined that the composite film having a PS:PVC mass ratio of 5: 3 and containing 3% MCC exhibits the highest tensile strength (20,32 MPa) and the tensile strength increased by 55% compared to the neat PS film.