S+B: How much are we seeing current industries attempt to mirror the abalone’s process?
BENYUS: Just about any ceramics manufacturer would be interested in a material that is twice as tough as what they’re currently making. One major roadblock is that translating the natural self-assembly process into an industrial process is very challenging. However, it is being done in a variety of places, like the Sandia National Laboratories at Albuquerque, where Jeff Brinker [a materials scientist at Sandia and the University of New Mexico] is creating self-assembling materials. He’s working on optically clear glass that could be used in windshields for cars. He starts with the liquid precursors of glass — basically, liquefied beach sand. Then he puts in a detergent kind of molecule that herds the organic material together into layers. You dip an object into a pot of the precursors and when you lift it out of the pot, the liquid evaporates and all the other materials set up like oil and water. You wind up with hundreds of layers of optically clear glass, separated by a thin layer of organics. It’s a very, very tough material — seven times tougher than our windshields.
It’s happening in other realms as well. In electronics, any chip manufacturer is looking into self-assembly of components, including the work with diatoms that I mentioned. Similar work is being done with dye-sensitive thin-film solar cells, which will eventually make solar power more affordable. Another promising technique is solid free-form fabrication, also called rapid prototyping, which builds three-dimensional objects layer by layer without any need for molding or shaping. Right now, it’s being used for product prototyping in all kinds of engineering and design studios, but some researchers are looking at how to scale the technique up to “print” a whole house. A CAD program would instruct a crane to lay down layer after layer of cement, or whatever building material you’d use, to build walls.
The researcher leading the charge on this, Rupert Soar at Loughborough University in Leicestershire in the United Kingdom, is finding all sorts of innovative applications for free-form fabrication. Right now he’s taking a slice-by-slice scan of termite mounds to see how their tunnels are formed; those tunnels are of great interest because they help keep the mounds at a consistent temperature, no matter what the weather. Dr. Soar wants to use the free-form fabricator to emulate the channels of a termite mound in the walls of your house to create a passive air-conditioning system. Self-assembly is a huge paradigm shift, but it’s the future of manufacturing.
Fringe to Mainstream
S+B: What will it take for manufacturing to abandon “heat, beat, and treat” for self-assembly?
BENYUS: It’s hard to predict when companies will start jumping in. Rising energy costs will certainly help push things along. But to catch on, any new manufacturing technique has to offer higher performance, and it’s got to be cost-effective. In biomaterials, people look for high-value products first. So, for instance, medical-products companies funded the research into mussel glue and have been investigating it for bonding knee ligaments and other surgical purposes. It was viewed strictly for high-value medical applications until they figured out how to make a mimic of the mussel glue inexpensively. Then it jumped over into very cheap products like plywood. Columbia Forest Products is now a big proponent of mussel glue.
A lot of companies are at the point where they’ve proven the concept and it makes sense for a manufacturer with a high-value application to fund the development costs. They need that next step of funding to bring it to industrial scale.