New milestones for biodegradable plastics in Japan and U.S.

Toray Industries in Tokyo, Japan, claims to have developed the first flexible bi-oriented film based on polylactide (PLA) biodegradable polymer, which is derived from cornstarch by bacterial fermentation. Until now, PLA has been lacking in flexibility, Toray says. Its answer is proprietary microstructure control based on alloying. No plasticizers are used. The PLA base resin is NatureWorks from Cargill Dow LLC, Minnetonka, Minn.

A second novel application of PLA is a biodegradable pipe developed by Mitsubishi Plastics, Inc. in Tokyo. The pipe is said to possess mechanical strength comparable to PVC. However, it can be completely degrad- ed in soil overthree to five years. Mitsu-bishi foresees its use as temporary pipe for short-term service in places where pipe recovery is difficult.

In the U.S., a water bottler and a dairy are the first beverage companies to package their products in NatureWorks PLA. Biota Water from Biota Brands of America Inc., Ouray, Colo., is now available in liter, half-liter, and 12-oz PLA bottles. The film labels are also made of PLA, although the cap is not. Monolayer PLA bottles can be molded on the same two-stage injection stretch-blow machinery as PET with no loss of output, according to cargill Dow. Sensory panel tests reportedly also show that PLA bottles have organoleptic (taste/odor) properties comparable to PET.

Meanwhile, a dairy farm consortium, Naturally Iowa, LLC in Clarinda, Iowa, is offering milk in a half-gallon "grip" bottle of PLA and is working with Cargill Dow to develop bottles for single-serve yogurt drinks. Cargill Dow is developing PLA bottle applications with makers of juices, ready-to-drink teas, and edible oils. Tel: [phone] * PTDirect: 112BV