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TPE Seat Belt Retention Solution


An automotive customer had been using ThermoPlastic Vulcanisate (TPV) in a specific seat belt retention boot application. However, the existing TPV material had cost, appearance and performance problems. The TPV supplier’s products could not meet the color specifications for the part in question, leaving the very real possibility that the customer could lose business.

The customer requested Mexichem Specialty Compounds to develop a lower cost, performance equivalent TPE solution to deliver the following improved properties:

  • A broader processing window
  • Consistent natural colour
  • Reduced Cycle times
  • Non-Hydroscopic
  • Better surface appearance
  • Cost savings over TPV material
  • Reduce lead-time

The Problem

The customer was receiving the TPV with inconsistencies in the natural colour. Consequently, the customer had difficulty in maintaining a consistent colour in the parts during injection moulding. To overcome this colour inconsistency, the customer shipped the natural TPV to a colour-compounding house in order to colour the natural TPV in the desired colours. The colour compounder had a long lead-time, and that added both delay and additional cost to the process.

The Application

Seatbelt retention boot.

The Challenges

Mexichem Specialty Compounds offered to develop a TPE compound to replace the problematic TPV product. The new TPE product would deliver several advantages. It would broaden the process window, reduce cycle times as well as be fully recyclable.

The TPE compound had a consistent natural colour, so the customer would be able to colour it during injection moulding. This would save on the long lead-time for custom colouring and the additional cost this generated. The Mexichem Specialty Compounds TPE compound, being non-hydroscopic, would also not require drying.

The Solution

The supplied new TPE product met all the customer’s key performance objectives. The TPE compound processed smoothly, had a better surface appearance and a consistent natural colour. It reduced cycle times and met the customer’s pricing needs. The TPE compound conformed to Chrysler and Ford specification.

The result

The prime advantage gained was that the customer received a TPE compound tailored to their specific and exacting need. The product delivered a better performing compound with shorter cycle times and, being non-hydroscopic, it contributed to a considerable time saving in the production process. It also eliminated the need for a colour-compounding house, therefore saving both time and money.

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