New Technology Yields Bioplastic Molding Blends
Physical properties of high-impact polystyrene are maintained
Doug Smock, Contributing Editor -- Design News, October 26, 2009
New options for use of plastics with plant-based content continue to grow for design engineers.
The most recent is a compound for injection molding applications that blends starch with high-impact polystyrene (HIPS) from the Bioplastics Div. of Teknor Apex Co.
TerraloyTM BP-18003A is a blend of thermoplastic starch (TPS) with HIPS, with up to 30 percent starch content. As an alternative, Teknor Apex also offers a new masterbatch, TerraloyTM MB-18003A, with TPS content ranging up to 50 percent. Both products are for use in typical HIPS applications such as cutlery, disposable razors and other consumer products.
"The new Terraloy products are the first polystyrene/starch blends that make it possible to effectively substitute for 100 percent HIPS in many applications," says Edwin Tam, manager of new strategic initiatives for the Teknor unit. "While starch acts like a filler in conventional blends with HIPS and is incorporated through techniques that cause a dramatic fall-off in physical properties, the proprietary technology employed by Teknor Apex for Terraloy products disperses TPS in the host polymer in a unique morphological form that minimizes property losses."
The new blend can be used with existing tooling and requires no modifications. The recommended letdown ratio for the Terraloy MB-18003A masterbatch is 1:1.
The announcement on Friday follows a flurry of activity in bioplastics at the 2009 National Plastics Exposition held in Chicago.
Highlights included:
· DuPont announced a fully commercial bioplastic product lineup.
· NatureWorks showed the latest developments for its Ingeo line of bioplastics,
· PolyOne announced a breakthrough series of solutions for natural fibers that expand processing and material options for the composites market, and
· Metabolix announced the next-generation injection molding grade for its Mirel bioplastic.
In a new technology, blends of bioplastic and polystyrene can be used for injection molding applications. Photo: Teknor-Apex
