Depending on thickness, parts made from Ingeo may be compostable in industrial compost facilities. This after-use treatment generally makes sense only when the plastics are contaminated with organic residuals, which is not usually the case in engineering applications, Diodato said. In these segments, NatureWorks directs its efforts toward recycling.
"If Ingeo and the alloy material it's blended with are treated effectively, there's no reason that an Ingeo blend has any less utility than the traditional petroleum-based blend after recycling," Diodato said. "The challenge is in the supply, in getting these products into the marketplace, so they create the need for a waste stream of recycled content. Until these materials are out there, they can't be recycled. Recycling is now happening at the post-industrial level, where manufacturers are collecting their own scrap."
"Most industries that use durable plastics are looking to use some type of green engineering polymer," said Vinny Sirani, business manager for BASF's Ultrason and Ultramid Specialties. With engineering polymers such as Ultramid Balance, engineers compare price to performance, and both must be in the right combination. "For example, Ultramid Balance has good performance compared to standard engineering polymers, but how can we make it more economical? They are also looking at the material's lifecycle to determine how sustainable it is."
For example, when automotive engineers make a materials decision about whether to go with a bioplastic or a standard engineering plastic for a part, if both are similar in performance, they will then consider price. "If it's not outside their range, they may consider a green product," he said. "But they won't consider one just because it's green."
Johan van Walsem, vice president of strategy and commercial development at Metabolix, said it offers Mirel, a biobased PHA (polyhydroxyalkanoate), the only nonstarch bioplastic that is both biobased and biodegradable. It can replace several petroleum-based plastics, including polypropylene, ABS, olefins, styrenics, and polycarbonate. The injection-molding grade can be processed on current equipment to make components for printers and computer peripherals with a cycle time similar to that of traditional thermoplastics.
Furst said most biobased feedstocks come from food-based crops, not the separated-out trash made as a byproduct such as cane trash. But efforts are increasing to develop alternative feedstocks that don't require growing food crops solely to harvest their waste and don't compete with food crops for land.