TPU Material Testing & Final Decision on EVA Foam

Date: 11/15/2025

Status: Prototype Material Evaluation

Over the last phase of development, we ran structured tests comparing TPU (Thermoplastic Polyurethane) against our previous EVA-based prototypes. The goal was simple: confirm whether TPU could deliver the stability, comfort, and long-drive support required for PillowFlow™.

We tested multiple TPU densities, molding variations, and structural designs to see how the material behaves under real driving loads.

TPU Testing Results

1. Compression Under Load

TPU showed excessive compression, especially under sustained weight. After 20–30 minutes of driving simulation, the lift under the thigh decreased noticeably, reducing support and increasing fatigue.

2. Shape Recovery Issues

While TPU is flexible, it struggled to return to its exact original shape after prolonged pressure. This created small but measurable dips in height that accumulated over longer trips.

3. Heat Sensitivity

Car interiors get hot. TPU softened significantly when tested inside a warmed cabin, leading to even more compression and instability.

4. Edge Deformation

The TPU prototypes developed rounded edges after repeated pressure cycles, losing the crisp geometry required for proper thigh alignment.

5. Comfort Feedback

Testers consistently reported:

• Less support

• More leg effort

• Reduced feeling of lift

• Faster onset of numbness during long sits

TPU simply felt “too soft and too rubbery” for structured ergonomic support.

Conclusion — EVA Foam Is the Superior Choice for Production

After TPU testing, the verdict is clear:

EVA Foam outperforms TPU in every category that matters:

• Support

• Stability

• Heat resistance

• Shape retention

• Comfort

• Long-term durability

EVA maintains its height, stays firm under heat, absorbs pressure gradually, and returns to its original form instantly — exactly what a thigh-support device needs.

Final Decision:
🔧 All production units of PillowFlow™ will be manufactured from premium molded EVA Foam.
This ensures maximum comfort, long-term reliability, and consistent ergonomic performance for every driver.