Bridging the gap between rubbers and plastics: a review on thermoplastic polyolefin elastomers

Thermoplastic elastomers (TPE) are studied for their unique properties of being easily processes and recycled. This paper focuses on the wide scope of thermoplastic polyolefin elastomers (TPO/TPE-O) which is one of the major classes of TPE. The performance of TPO is the cumulative effect of polyolefins and rubbers with the ease of processing due to the presence of thermoplastics. The study focuses on the classification of TPO, their routes of synthesis, composites, applications, and its impact on environment. The mechanical blending of polyolefins and conventional rubber was carried out to manufacture TPO. In further developments, the polyolefin elastomers (POE) were synthesized by copolymerization techniques to overcome the drawback of mechanical blending techniques. Environment-friendly blends of TPO are synthesized using industrial and municipal waste which includes scrap rubber tires, marble waste-filled polypropylene, computer body waste, etc. This technology will help in reducing the issue of landfills. The composites of TPO have been studied using different types of fillers which may be synthetic or bio-based. These include talc, carbon black, carbon nanotubes (CNT), Kenaf fiber, pineapple leaf fiber, etc. TPO have found their use in encapsulation, in electrical insulation, roofing, medical devices, and the automobile industry. Also, impact of using TPOs on environment is discussed here qualitatively.