On the Potential of Upcycling Plastic Wastes to Carbon-Capturing Materials Using Supercritical Fluid-Assisted Injection Molding Process

<div>With the extensive production and widespread use of plastics, the issue of environmental pollution caused by plastic waste has become increasingly prominent. Consequently, researchers have been focusing on developing efficient methodologies for upcycling waste plastics and converting them into value-added materials. This hybrid review–conceptual article first provides an overview of strategies for upcycling waste plastic into carbon-capturing materials. It presents carbonization and activation as key steps in converting plastic waste into adsorbent materials and explores strategies for converting common waste plastics. Building upon this foundation, the article introduces and conceptualizes a novel upcycling approach with two manufacturing routes to convert plastic waste into carbon-capturing materials using supercritical fluid (ScF)-assisted injection molding process. It continues by investigating the potential of developing lightweight components made of such carbon-capturing materials for transportation and construction applications. Through a combination of review and conceptual exploration, this research demonstrates that the ScF-assisted foaming process can effectively convert plastic waste into materials with enhanced mechanical properties and effective carbon dioxide (CO<sub>2</sub>) absorption capacity. Successful realization of this concept will be a promising advancement in developing sustainable materials and technologies that can contribute to mitigating the negative effects of both plastic waste and CO<sub>2</sub> emission, hence supporting the shift toward sustainable, environment-friendly transportation.</div>