New Resins for Cut Sheet Thermoformers

Large part thermoforming is growing by leaps and bounds, affording thermoformers an unparalleled opportunity to expand their businesses into new market segments. Previously, the delicate balance of impact, stiffness and formability requirements had prevented large part thermoforming from being completely effective. However, new advances in material science are making these concerns a thing of the past.

The Dow Chemical Company has developed a new performance plastic specifically designed to meet the needs of cut sheet thermoformers. The new polymer, INSPIRE™ EFP 500 Performance Polymer, overcomes key barriers in existing thermoplastic olefin (TPO) technology.

Dow worked with thermoformers to identify performance gaps in current thermoforming options. INSPIRE EFP 500 Performance Polymer was engineered using Dow’s patented technologies for both polypropylene and elastomers. It addresses concerns about sag and warpage in large thermoformed parts where achieving the optimum balance between stiffness and formability is crucial. The polymer provides enhanced design flexibility, enabling curvatures and three-dimensional shapes expected from thermoformed parts. At the same time, it contributes to excellent dent resistance and durability in the finished product, providing a combination of performance characteristics that exceeds existing TPO technology.

The polymer addresses two additional gaps in current thermoforming technology – melt strength and regrind. Its high melt strength is expressly formulated for optimum performance in thermoforming applications. The new polymer also enables thermoformers to use up to 40 percent regrind without significant loss of properties. This is a substantial improvement over current technology, where even small amounts of regrind can result in decreased performance of the final part.

The polymer provides excellent low temperature toughness, ductility, chemical resistance and fastening capabilities, designed to meet the evolving needs of today’s thermoformers.

It works extremely well at high output rates, allowing for increased processing speeds, and can be used on existing sheet and forming equipment. For finishing, it can be used by itself or with a complementary high gloss cap layer with UV and scratch resistance.

INSPIRE EFP 500 Performance Polymer is suitable for many durable goods, such as sporting goods, automotive parts, RV parts, canoes/kayaks, all-terrain vehicles and tractors.

In the coming months, Dow plans to introduce another TPO compound specifically designed for cut sheet thermoforming. Developed using Dow’s material science-based approach, the new material has a flexural modulus greater than 500,000 psi with excellent impact resistance. It has shown dramatic results in production speed and performance.

These new materials significantly broaden the application opportunities available to large part thermoformers. By overcoming traditional barriers, Dow and other resin producers are opening the door for thermoformers to take advantage of this high-potential process technology. With the aid of polymer innovations that raise the bar for performance, large part thermoforming is poised for significant growth.

Written by Ben Matuska, North American Market Manager for Plastic Durable Goods, The Dow Chemical Company, 400 W. Sam Houston Parkway, Houston, TX 77042, 713-978-2312, Fax: 713-978-6259, Web: www.dow.com