High flow, foamed PC alloy grades make inroads in exterior components

Japan’s Kaneka Corp. (Osaka) is developing a polycarbonate alloy that can be foamed by a factor of up to two. The company is targeting automobile exterior panels as a key market for the new product, which has been successfully injection molded using the “core back” process in a thickness of 2 mm.

Kaneka has molded 1500 x 200 mm sample panels using the new grade in a thickness of 2 mm. Compared with a 0.8-mm-thick steel panel weighing in at approximately 1.9 kg, the foamed PC alloy panel weighs just 610 g or so. This compares with around 830 g for a panel molded from Kaneka’s Hyperlite JP PC/PET high flow alloy.

Kaneka employs a chemical blowing agent in its process that reportedly delivers a superior surface finish after painting versus panels that are foamed with gases such as nitrogen.

Kaneka introduced its prototype, patent-pending PC alloy at the recent Automotive World show incorporating the 7th Automotive Lightweight Technology Expo held January 18–20 in Tokyo. The supplier’s Hyperlite JP high flow PC/PET alloy was also showcased for adoption in components such as front hood covers, rear spoilers and garnishes, roof side covers, and slide door end garnishes. The first commercial application is in the rear roof garnish of the latest Toyota Prius model.

With 15% filler loading, the grade’s spiral flow is 525 mm at a thickness of 2 mm. This compares with 390 mm for a conventional grade.