Huntsman makes splash with liquid TPU 'first' for footwear

The Woodlands, Texas – Huntsman has claimed a ‘footwear industry first’ with the development of a liquid thermoplastic polyurethane (LTPU) for 'rapid manufacture' of midsoles.

The LTPU system can be processed in a single step that uses “significantly less water and energy and generates less waste and carbon emissions,” Huntsman announced 19 Sept.

As unveiled at the Italy Simac machinery show in Milan, the Smartlite O LTPU can also be converted and repurposed into new materials either in its post-industrial or post-consumer form.

The product, according to Huntsman, is easier to use than expanded forms of TPU, which require complex procedures such as supercritical foaming and steam chest moulding.

To launch the lightweight product, Huntsman joined forces with Framas Group, a Germany-based polymer processor focused particularly on the footwear industry.

The group, Huntsman said, has capacity to produce up to two million soling constructions per annum using its new material.

The liquid TPU enables short cycle times as it provides “in-situ polymerisation, adhesive-free bonding of midsoles to TPU outsoles, and fast demould rates,” continued Huntsman.

Furthermore, the polymer system yields “hydrolysis resistant midsoles” and step-in cushioning comfort with a rebound of more than 50%, the materials company added.

“A number of big brands have already expressed considerable interest in the technology, Alexis Bortoluzzi, senior director at Huntsman global elastomers, reported in the release.