As blogged on MIT Technology Review, humanity’s reliance on plastic is a significant problem. This material is derived from petroleum and generally ends its life as landfill and or in an incinerator. Either way, that’s unsustainable. So why not develop biocomposites that are more environmentally friendly?
That’s not as simple as it sounds. Most biodegradable plastics rely on a matrix structure derived from petroleum. That’s because biological matrixes generally lack the strength for most engineering and structural applications.
Then there is natural wood, which can be processed to give it properties that rival steel and ceramics. But this processing requires harsh chemical treatments that are not environmentally friendly.
So there is intense interest in finding ways to turn ordinary plants into biocomposites that are sustainable and comparable in mechanical performance to processed wood and to conventional plastics.
Enter Eleftheria Roumeli and colleagues at the California Institute of Technology. This team has found a way to turn cells from tobacco plants into a hugely strong material with wood-like mechanical properties. “We have developed a new method to create natural biocomposite materials based on plant cells,” they say. “[The materials’] stiffness and strength surpass that of commercial plastics of similar density, like polystyrene, and low-density polyethylene, while being entirely biodegradable.”
The manufacturing method is straightforward. The team start with cells from the herbaceous plant Nicotiana tabacum, which they culture in liquid suspension in the lab. This widely grown plant produces leaves that are processed into tobacco.