High-density polyethylene matrix hybrid composites: a review of their characterization, processing techniques, and promising applications

Thermoplastic matrix polymer composite materials have gained considerable attention in various applications as a result of their good versatility, durability, corrosion and wear resistance, rigidity, high dimensional stability, high ductility, lightweight, and ease of processability. High-density polyethylene (HDPE) is one of the most versatile and mostly utilized thermoplastic due to its desirable properties such as reduced production cost, chemical resistance, excellent thermal insulation properties, physical properties, reasonable tensile strength, low temperature toughness, flexibility, considerable hardness, high crystallinity, minimal water absorption and good resistance to corrosion. This paper is designed to provide a comprehensive review of HDPE matrix and its comparison with some other polyethylene plastics, reinforcement types of natural fibers, synthetic fibers, and particulate fillers and their contributions to composite properties. It further delves into characterization techniques (mechanical, thermal, morphological) of hybrid HDPE composites and effects of hybridization the properties. Different processing techniques were also addressed and lastly promising applications of hybrid HDPE were discussed. After reviewing previous studies, it is clear that blending two or more reinforcements brings significant improvement in mechanical and thermal properties of composites and has the potential to be utilized in high end applications such as medicine, aerospace and military applications.