Green Alternative to Traditional Plastics
Apr 06, 2011 02:05AM
● By Gerald Deredita
Imagine a biopolymer used to make everything from commercial packaging to fibers for apparel and is derived from 100% annually renewable resources instead of oil. A biopolymer that offers more disposal options and is more environmentally friendly to manufacture than traditional petroleum-based plastics. PLA or polyactic acid is just that.
NatureWorks LLC has a proprietary process for manufacturing NatureWorks® PLA which centers on the fermentation, distillation and polymerization of dextrose, a simple plant sugar made from field corn. In addition to corn, they are exploring and evaluating other abundant, inexpensive, non-food-nutrient crops for potential future use as an alternative natural source of sugar to create PLA. The company essentially harvests the carbon stored in the sugars to make polylactic acid (PLA), a polymer with similar characteristics to traditional thermoplastics. All this while decreasing fossil fuel consumption by 65% compared to traditional plastic.
After harvesting, corn is transported to a corn wet mill where the starch is separated from the other components of the corn kernel and into dextrose. In the subsequent process, the dextrose is fermented (a process similar to wine or beer) into lactic acid. Lactic acid is the naturally occurring material that gives the "tang" in yogurt and makes your muscles ache after working out. From lactic acid, they create a molecule called lactide. They remove water, crystallize it and create a polymer. The polymer is a small, clear pellet about the size of a small fishing sinker weight, or tiny pebble.
To be processed into IngeoTM fiber, filament is extruded from pellets and spun into yarn for knitting or weaving apparel. Pellets are also used in an injection stretch blow molding process to form clear PLA water bottles and jars. It can be shaped into a variety of containers, trays, film and other packaging. It can be physically and chemically recycled, composted and can break down into carbon dioxide, water and humus.
For more information on PLA and view product examples go to www.Amedank.com.