Automotive & Transportation

Circular Automotive Foams: Recyclable TPE for Soft-Touch Parts

Foamed TPE and PP could replace non-recyclable automotive soft-touch structures while reducing weight and increasing recycled content.

Upcoming European regulations require automotive applications to incorporate at least 15% post-consumer recycled plastic by 2032, and 25% by 2036. With this increasing pressure, there is a need to look for circular material solutions for end-of-life vehicles (ELV).

You can also read: Polypropylene Recycling from Disposable Face Masks

Recyclable TPE for Soft-Touch Parts

Foams, in particular, are widely used in soft-touch applications inside the vehicle and are the focus of several new developments. One approach aims to replace thermoset foams and composite foamed structures with thermoplastic, recyclable alternatives.

A research project at the IKV, Institute of Plastics Processing in Aachen, Germany, aims to develop circular foamed products for soft-touch applications. In this case, the objective is the substitution of non-recyclable composites through foamed TPE (thermoplastic elastomers).

Conventionally, soft-touch components are made from a thermoplastic carrier (such as PP or fiber-reinforced PP), a polyurethane foam, and a decorative layer made of PVC or leather. The project “Foam2Cycle”, currently under development and funded by the German Federal Ministry for Economic Affairs and Energy, investigates a thermoplastic structure that combines structural PP with TPE, produced via foam injection molding using physical foaming agents.

A new process developed at the IKV targets the production of a mono-material soft-touch thermoplastic component. This alternative replaces composite structures, and the foaming is achieved via foam injection molding with an expansion of the mold cavity. Image courtesy of IKV.

IKV has used “breathing mold” technology for several years to promote cell growth after the cavity fills. In this process, the mold cavity expands after filling, allowing the blowing-agent-rich material to develop a cellular structure.

The process starts with a rigid PP core that already contains a cellular morphology. Manufacturers then overmold the core with a mixture of TPE and physical blowing agent. Once the cavity is filled, the mold expands and creates a sudden pressure drop. This pressure change promotes nucleation and enables cell growth throughout the TPE, significantly reducing material density.

The approach offers several advantages for automotive soft-touch applications. First, manufacturers can integrate the soft-touch function into a single molding process. In addition, the all-thermoplastic structure improves recyclability compared with conventional multimaterial assemblies. The process may also lower production costs by reducing the number of separate layers and assembly steps.

However, successful foaming depends on precise process control. Mold-wall temperature, opening stroke, and opening speed all influence cell morphology and the achievable degree of foaming. Therefore, manufacturers must balance these parameters carefully to obtain a homogeneous structure and consistent part performance.

Controlling Foam Morphology and Weight Reduction

The project currently studies the interaction between these parameters and the molding processing windows to achieve homogeneous foam morphology with significant weight reduction. Currently, it is possible to achieve a weight reduction between 50% and 80%.

An inadequate control of the expansion process may result in several defects in the foam structure. For example, the foam structure in the core may tear up. Also, insufficient nucleation or foaming-agent escape before foaming can result in a low degree of foaming. The target is to obtain a homogeneous foam structure, as seen in the middle section of the image below.

Homogeneous foam structure (middle) in contrast to defects (left and right) caused by unfavorable process control. Image courtesy of IKV.

Tailoring Soft-Touch Performance

The project furthermore studies how to tailor the haptics of the soft-touch component. At K 2025, a demonstration showed the incorporation of over 30% recycled material to meet ELV regulations.

Typically, the injection molding process delivers surface qualities that are not acceptable for automotive indoor standards. Another objective was to develop texturized mold surfaces, which may mask defects inherent to the foaming process.

Finally, to ensure part quality, the project analyses how to couple an optimized indentation test method to obtain relevant information about foam quality, within the limited time of a production cycle. This test may allow parameter adjustments to ensure consistent part properties.

By Laura Florez | September 24, 2026

Recent Posts

  • Artificial Intelligence

New German Project Uses AI and Batch Data to Improve PCR Quality

AI sorting, data-driven compounding, and digital traceability improve PCR purity, consistency, and confidence across recycling…

1 day ago
  • PFAS

Chemical Safety in Plastics 2026 Tackles PFAS Reformulation

PFAS restrictions are forcing plastics suppliers to reformulate high-performance materials without sacrificing heat, friction, or…

2 days ago
  • Injection Molding

Similar Settings, Different Flow Marks: The Role of Melt Behavior

Dimensionless analysis links flow-mark formation in polypropylene injection molding to melt relaxation, cavity scale, and…

3 days ago
  • Industry

AI Injection Molding Ecosystem: Smarter Together

The AI Injection Molding Ecosystem is not about predicting the future. It connects materials, simulations,…

5 days ago
  • Recycling

Flexloop Targets High-Purity Recycling for Flexible Packaging

Flexloop uses solvent extraction to remove inks, adhesives, odors, and contaminants from flexible films, enabling…

6 days ago
  • Additives & Colorants

Why Plastic Additives Matter for Performance and Circularity

Plastic additives enabled global polymer growth, but today they also create new challenges for recycling,…

1 week ago