Plant-based plastics are still in their infancy — that means there's an opportunity to sustainably manage their growth through so-called green chemistry.
Two leading bioplastics researchers argued that in keynote speeches May 6 during a new technology forum on advances in polymers from renewable resources at the annual Society of Plastics Engineers Antec conference in Milwaukee.
``Anybody involved in bioplastics, you've got a lot of room to grow today,'' said Jim Lunt, managing director of business development specialists Jim Lunt & Associates LLC and a co-founder of biopolymer pioneer NatureWorks LLC of Minnetonka, Minn.
Lunt said European Bioplastics eV, a Berlin-based trade association, estimates annual global production of bioplastics by 2011 will increase to 2.2 billion pounds, up from 578 million pounds produced in 2007.
``This will still only be 0.7 percent of the approximately [508 billion pounds] of plastics in use today,'' he said.
But consumer and governmental moves toward products perceived as being less dependant on petroleum and more environmentally friendly will drive up demand for bioplastics, he said.
Bioplastics have made their way into important pieces of legislation, Lunt said.
c The Japanese government has set a goal that 20 percent of all plastics consumed in Japan will be renewably sourced by 2020.
c Germany has a phased-in ban on solid waste with more than 5 percent organic content in its landfills; that will affect bioplastics starting in 2012. Korea and Taiwan have similar laws in place.
c Under the 2002 Farm Security and Rural Investment Act, each U.S. federal agency must design a plan to purchase as many bio-based plastics as practically possible.
In addition to new laws, Lunt said, petroleum feedstocks are drying up: For every four barrels of oil used, only one new barrel is discovered. Petrochemical-based plastics consume about 2.5 billion barrels of oil annually, he said. ``The incentive for bioplastics is getting much more attractive to people,'' Lunt said.
Today's bioplastics leaders — including Braskem SA, Cereplast Inc., DuPont Co., Metabolix Inc., NatureWorks, Novamont SpA and Tianan Biologic Material Co. Ltd. — will be joined by new companies including Arkema SA, BASF AG, Dow Chemical Co., Crystalsev Comerico e Representacao Ltda., Rohm and Haas Co., Royal DSM NV and Tianjin Green Bio-Science Co. Ltd., he said. Lunt is Tianan's vice president of sales and marketing.
The focus of bioplastics is changing from end-of-life cycles to making more durable products from future plant-based feedstocks, Lunt said. By 2011, automotive and electronics applications will account for almost 40 percent of the global bioplastics total, compared with 12 percent today, he said.
In addition to polylactic acid, polyhydroxyalkanoates, polyhydroxybutyrate valerate and other bioresins in use today, tomorrow's market leaders will produce green low and high density polyethylene, polypropylene, acrylics and nylon, he said.
Some in the plastics industry are getting hung up on whether bioplastics merely contain plant-based additives, are biodegradable, or both, said Lunt and Ramani Narayan, professor of material science and engineering at Michigan State University.
``What it is all about is carbon,'' Narayan said. ``We are made of carbon units. Everything we touch [and] do is based on carbon. We live in a carbon economy and are driven by a carbon economy.''
Biodegradable and bio-based are not necessarily exclusive terms, both men said. Narayan said there's no use arguing over which is better: in the end it all comes down to carbon emissions.
``When you're talking `bio-based' or you're talking `biodegradable,' or `renewable,' … you're really talking about carbon footprints and the ability to reduce it. It's a feedstock focus as opposed to petroleum,'' he said.
More importantly for plastics engineers, he said, is to bear in mind that if biodegradable products are not removed form their defined disposal environments — whether that be composting, burial, anaerobic digestion or water — degraded fragments of plastics become potential toxin carriers up the food chain, resulting in serious health risks.