Effect of the Graphene Nanoplatelets (GnPs) on the Mechanical Properties in Recycled PP-Based Hybrid Composites

Abstract

© 2022, The Society for Experimental Mechanics.In the day we fight against Covid-19, the use of disposable masks and isolation clothing is multiplied by 12 compared to the time before the Covid-19 pandemic. Considering that these disposable masks are made of polypropylene (PP), an average of 480 kilotons of PP waste is produced each year, exclusively from masks. After the use of these masks, it is important to collect and re-evaluate them in a controlled manner so as not to pose a risk of contamination and not to threaten the environment. Because of its advantageous properties, PP is used in the production of many parts in the automotive industry. With this study, it is aimed to develop composite materials to be used in car bumper manufacturing by using recycled PP obtained from melt blown PP fabrics (surgical mask fabric). Due to accidents or road conditions, impact damage can occur on the bumpers. Therefore, the impact resistance of the bumpers must be improved. In addition, in case of microscale damage resulting from the impacts received, microcracks may develop and cause material failure below the maximum tensile stress. In summary, effective reinforcements should be used to improve impact strength in composites for use in car bumpers. Accordingly, novel recycled PP (rPP) based composites are manufactured by using elastomer-styrene-ethylene-butylene-styrene (SEBS) and graphene nanoplatelets (GnPs) as compatible reinforcements with rPP. As experimental characterization, three-point bending tests and Charpy impact tests were carried out. Incorporation of GnPs increased the flexural strength and blending with SEBS improved the impact resistance of the developed composites. Certain clusters of the graphene nanoplatelets were observed by means of microscopy.