Toyoda Gosei Launches Automotive Parts With High Recycled Rubber Content

Toyoda Gosei has commercialized automotive weatherstrip components with a significantly increased proportion of recycled rubber material, introducing these parts on Toyota Motor’s RAV4 and targeting broader deployment in vehicle sealing and hose applications.

New automotive parts using high recycled rubber content
Rubber recycling poses unique technical challenges in the automotive data ecosystem due to crosslinked sulfur bonds that give elastomers their mechanical properties. Devulcanization to break those bonds traditionally reduces tensile strength and retains odor-causing byproducts, limiting the recycled fraction in new parts to below 5 percent and thereby constraining rubber circularity in transportation supply chains. Toyoda Gosei reports that incremental improvements to its proprietary devulcanization processes have delivered regenerated rubber of sufficient mechanical quality to raise the recycled fraction to 20 percent in mass-balance-managed components.

The initial deployment in vehicle sealing systems places the technology in weatherstrip applications, which are typical elastomeric interfaces for doors, windows, and other apertures used across most light-duty vehicles.

Technical basis and mechanism of improvement
The innovation centers on refining the devulcanization step, which uses heat and pressure to break sulfur crosslinks. Optimizing this reaction mitigates collateral cleavage of polymer backbone bonds, improving recovered material strength. While the specific reaction parameters are not disclosed, the company states that progress in these processing conditions increases the usable proportion of regenerated rubber in components without unacceptable loss of mechanical performance or additional odor.

The manufacturing facilities include ISCC PLUS certification and use a mass balance approach, which quantifies sustainable material content across processes and enables verifiable allocation of recycled feedstock to finished goods.

Applications and prospective expansion
The technology applies predominantly to ethylene–propylene rubber (EPR-type) formulations used for weatherstrips, with development underway to extend it to natural rubber and to systems such as automotive hoses. Commercial deployment in Toyota’s RAV4 acts as a functional demonstration within the digital supply chain of vehicle components, validating the material properties for sealing duties at scale.

Industry significance and collaboration model
Industrialization of a higher recycled-content elastomer addresses one of the harder-to-recycle material streams in vehicles, where rubber is typically incinerated for thermal recovery rather than reused. By collaborating with automakers and partners to collect rubber from end-of-life vehicles and regenerate it into components, the company aims to operationalize a circular system for elastomers, integrating recycling logistics with component manufacturing.

This positioning aligns with broader decarbonization goals in transportation by reducing reliance on virgin elastomer feedstocks and associated lifecycle emissions.

Circularity initiatives for metals and plastics in vehicles have clearer benchmarks and established closed-loop models, whereas elastomer recycling has lagged due to mechanical degradation in devulcanization. The reported increase from less than 5 percent to 20 percent recycled content in functional parts provides a measurable improvement relative to typical recycled rubber incorporation rates, offering a reference point for evaluating similar technologies.

The development of weatherstrip parts with 20-percent recycled rubber content demonstrates a functional approach to elastomer circularity in vehicles. While dependent on devulcanization quality and mass-balance certification, the advance suggests a path to broader recycling of both synthetic and natural rubber in automotive components, subject to further engineering validation and scaling within supply and recovery networks.

www.toyoda-gosei.com