New TPOs look beyond instrument panels, fascia

Sterling Heights, MI - By 2010, North America will become a net importer of polyolefins, with the potential for an additional 10 kg of advanced thermoplastic polyolefins (TPO) being utilized in automotive applications like body panels, wheel covers, roof rails, roof drainage tubes, and inner door modules. That’s the prognostication offered by Basell’s Stephen Dwyer, senior VP Advanced Polyolefins out of Lansing, MI for the polyolefins’ supplier.

Speaking to MPW after addressing participants at the Society of Plastics Engineers’ TPOs in Automotive Conference (Oct. 10-12, Sterling Heights, MI), Dwyer said Basell’s new reactor-grade TPO grades could displace talc-filled compounded polypropylenes (PP) in bumper fascia and pillar trim applications requiring energy management. These products are also excellent building blocks for applications like instrument panels and bumper fascia where TPOs already enjoy healthy market shares. On a global polyolefins supply basis, Europe will become a larger importer of polyolefins, with China and India driving demand and new production coming from the Middle East.

“The performance requirements are increasing, and [suppliers] also have to meet the cost requirements,” Dwyer said, “so with the versatility of this material, we see opportunity that you can actually make both happen.” Basell has introduced two new reactor-grade TPOs using the company’s Catalloy polymerization technology, with the materials offering low shrinkage and coefficients of linear thermal expansion (CLTE) that reportedly match the performance of a 10-20% talc-filled product. Basell also says the plastics reportedly offer low gloss, good cosmetics (no tiger striping), and good stiffness and impact performance.

For Dow Chemical’s (Midland, MI) specialty plastics and elastomers unit, automotive remains a major market, accounting for 25% of its North American business, according to Dave Kyle, senior marketing manager automotive, who also sees more opportunities for TPOs beyond traditional applications. “For the most part, bumper fascia are virtually converted to TPO,” Kyle said. “We continue to see healthy growth in terms of new material substitution,” pointing specifically to the displacement of PC/ABS for instrument-panel substrates or carriers, and applications like molded-in-color pillars for TPOs.

Dow sees potential in soft TPOs going forward, pushing its Infuse olefinic block copolymer launched at NPE as a replacement for styrenic block copolymers, offering similar performance at a lower system cost. A foam-in-place system for instrument panel skins could take on flexible polyvinyl chloride on the low end of the price scale, and spray polyurethanes systems at the opposite end of the cost spectrum, offering the added benefit when joined with an olefin-based carrier of recyclability.

Globalization of the automotive industry was also a theme at the conference, with Dwyer saying his company is working with OEMs like General Motors to standardize the materials it supplies so that TPOs for fascia made in Michigan are the same as those offered in Mumbai. Charles Buehler, technical integration engineer at GM presented a paper at the conference entitled “Globalization of TPO at General Motors” wherein he said GM North America has reduced the number of TPO specifications from more than 20 down to two. The company is now taking on common specifications (GMW15187, GMW15188) looking at critical material properties, including CLTE, shrinkage, and stiffness.

“Right now you have some OEMs that are pretty far along as far as working on a very global basis so they have one component, one type of material, one type of process, and they want that throughout the world,” Dwyer said. “What we’ve done is established ourselves so that we can supply materials to meet those specifications.”—Tony Deligio; [email protected]