Genomatica - Plastic-Producing Bacteria  

Inhabitat has an interesting post on a new bioplastic developed by a company called Genomatica - Scientists Develop Plastic-Producing Bacteria. More at Cleantech.com.

Scientists at Genomatica Inc. recently announced that they have developed strains of bacteria that are able to produce plastic without the use of oil or natural gas. The sustainable process utilizes little more than sugar and water to produce butanediol (BDO), which can be manufactured into everything from plastics and fibers to pharmaceuticals. Genomatica estimates that within a year the energy-efficient process will cost less than current hydrocarbon-based processes - a revolutionary development since close to 3 billion pounds of BDO manufactured each year.

Currently BDO is made exclusively with oil and natural gas, and its production is very energy-intensive. Utilizing sugar and E. Coli to create the chemical allows the production process to be conducted under normal pressure and temperatures, which drastically cuts it energy use: “By using advanced computational modeling and evolution‐based methods to rapidly engineer living organisms, Genomatica can produce valuable chemicals from renewable feedstocks at low cost.”

The bacteria-grown plastic can be produced in large fermentation tanks in a manner similar the way that algae is being used to produce biofuels, and the company plans on using sugars that are non-competitive with the food industry to steer clear of some of the conflicts that have been brought up with ethanol-based fuels.

Bioplastics were the first choice. We've written about the researchers at the University of Warwick who made cell phone cases out of a biodegradable polymer which comes with an embedded sunflower seed--just drop the case in the ground and it composts and releases its seed. We've also mentioned how NEC made a cell phone whose case was made out of the bio-plastic PLA reinforced with kenaf fiber. Both of these projects were groundbreaking and took extensive R&D to accomplish. They have yet to be duplicated by other manufacturers. PLA is being used by itself in many applications--mostly food packaging--and although it is still new to the market, it is quickly becoming the most successful bio-plastic. We've written about PLA before, but the best article about it on the web is by Smithsonian Magazine. The more prosaic Nylon 11, which has been around for decades, is also a bio-plastic: it is made from castor bean oil. However, since it was not invented with ecological impact in mind, it is not compostable and does not save significant energy in its manufacture like PLA does.

Unfortunately the company I was working for, like most normal companies, does not have years to research cutting-edge materials like the University of Warwick or NEC. They also have tight engineering requirements for the product which made it unfeasible to use off-the-shelf PLA or Nylon of any kind. In fact, as great as PLA is, it has the problem of melting at 114°C, which means it'll melt if you leave the product on your dashboard on a hot sunny day.

In the end, the product's engineering requirements dictated that we use polycarbonate or ABS. At first I was dead-set against that because they are recycling coded "other", so almost no cities in the US recycle them. However, the biggest impact of our little electronic device will be the circuit board, not the case, and we will have a takeback program with a strong incentive for users to send their old devices back to us. The companies who take electronics for recycling all recycle polycarbonate and ABS, so we can consider them recyclable materials after all. Still, using recyclable plastic is not enough. You're not really recycling unless you're making your device from recycled material. I investigated using 100% recycled plastic as our material, so that we do not cause any new plastic to be manufactured, and so that we can prevent existing plastic waste from going to landfills.