Electricity And Plastic

In Mike Nichols' classic film, The Graduate, a businessman takes young Benjamin Braddock (Dustin Hoffman) aside and gives him advice for finding a long-term career in an up-and-coming industry. The one word Benjamin is told will change his life? "Plastics." Indeed, plastics have become ubiquitous in our daily lives, but scientists have not stopped innovating in terms of design and figuring out additional ways they can be used for the betterment of mankind. In addition to making our automobiles lighter and keeping our food fresh, plastics will soon help generate and conduct the electricity we need.

What are plastics in the first place? Most any kind of malleable substance that can be bent, molded or pressed and consists of large, repeating molecules is a plastic. The molecules usually have covalent chemical bonds, which means that the molecules are bound by the outer shells of electrons, which means the bonds aren't as strong as in some other materials. This somewhat weaker bond is what allows you to fold a plastic sandwich bag. The term "plastic" comes from the Greek "plastikos," which means "fit for molding."

While it may seem that plastics are all man-made, they are actually common in nature. Rubber, produced from rubber trees, is a natural plastic. Advances in bioplastics are allowing engineers to develop an increasing number of materials that aren't derived from fossil fuels, as most consumer plastics are.

Researchers at the University of Washington are working to create plastics out of nanomaterials that will generate electricity, much like traditional solar panels do today. (Nano means small; the plastics are made from microscopic fibers.) Once the research team, headed by David Ginger, is able to create a stable material and perfect the process on an industrial scale, the demand on the American power grid could be reduced somewhat. Instead of charging your cell phone through standard wall outlet, you could plug it into your purse. As you go about your day, the purse will be hit by photons (the light/wave components of light) and the juice your phone needs will be produced without a second thought from the user. According to an article on Chemistry Times, Ginger and his team don't expect to reach the ten percent energy threshold, the point at which the polymer would convert ten percent of the electricity possible. Still, the progress they have already made is amazing, considering they are working with details "roughly 10,000 times smaller than a human hair."

The larger applications of such plastics are still in the planning stages, but these materials could serve the same purpose as solar panels, but eventually do so with a much smaller area. These electricity-generating plastics could also be incorporated into MP3 players, backpacks and other accessories we take everywhere.

Another interesting development in the convergence of plastic and electricity has been accomplished by scientists at the Frauenhofer Manufacturing Engineering and Applied Materials Research Institute (The IFAM) in Bremen, Germany. Plastics are ordinarily brittle, poor conductors of electricity. Metals, on the other hand, are easy to shape and conduct electricity quite well. A recent article in Science Daily described the IFAM's attempts to merge the properties of plastics and metals. As the article notes, metals and plastics are currently two separate components that must be joined together instead of simply molded. A computer circuit board, for example, is a sheet of plastic, on which copper and other metals are stamped and otherwise attached. If a computer board could be simply poured instead of stamped over many steps, manufacturing efficiency would be greatly increased.

Scientists at the IFAM have created a combined, composite material that is lightweight like plastic, but conducts current after the fashion of a metal. The end result is seamless and less susceptible to damage from the rigors of phase changes during power-ups and power-downs. (Each time you start up your computer, for example, the metal connections on your motherboard expand from the heat and then cool after you shut it down. This expansion and contraction can, in time, result in a break.)

These electrical plastics will likely be used in places in which a lightweight material should conduct electricity. When an airplane with a fiberglass fuselage is hit by lightning, there is no efficient place for the charge to go. (Metal has been bypassed in many aircraft fuselages because weight reduction saves a great deal of fuel and the engine.) If the aircraft body were made from one of these new materials, a lightning strike would be slightly less dangerous.

Although science has already changed our society in so many ways, there are always further advances. The possibilities granted humanity by photoelectric and electrically sensitive plastics will be explored and change our lives for the better.