The Thinkers: For CMU scientist, the one word is plastics
Tucked inside the columned recesses of the Mellon Institute in Oakland are the laboratories of one of the world's most famous scientists.
Krzysztof Matyjaszewski, the J.C. Warner professor of natural sciences at Carnegie Mellon University, is an expert in plastics, but not the kind you're most familiar with.
Instead of working with the straightforward polymers you pack your groceries in or drink your pop from, Dr. Matyjaszewski creates exotic plastics that are used for everything from high-end auto paint to pollution-eating particles to sealants for windows in high-rise office buildings.
And while "famous" is a subjective term, there is an objective measurement that makes him worthy of the adjective.
According to the scientific division of Thomson Reuters, Dr. Matyjaszewski ranks third in the world for the number of times his research papers have been cited by other chemists in their studies. In addition, Thomson Reuters said, there is a high correlation between the most-cited scientists and those who go on to get Nobel prizes, and it has mentioned Dr. Matyjaszewski -- pronounced Matt-uh-CHEFF-skee -- as a potential Nobel winner in chemistry.
His citation count reflects the exploding popularity of the technique his lab pioneered about 15 years ago, a process for creating specialized polymers known as atom transfer radical polymerization.
- Position: University professor and J.C. Warner professor of natural sciences, Chemistry Department, Carnegie Mellon University
- Age: 58
- Residence: O'Hara
- Education: Bachelor's and master's degrees, Moscow Technical University, 1972; Ph.D. in chemistry, Polish Academy of Sciences, 1976
- Previous positions: Chairman, Carnegie Mellon Chemistry Department, 1994-98; research associate, Centre National de la Recherche Scientifique, 1984-85; research associate, Polish Academy of Sciences, 1978-84
- Professional honors: Herman F. Mark Senior Scholar Award, American Chemical Society, 2007; UK Macro Medal, outstanding achievements in polymer science, 2005; Foundation of Polish Science annual prize, 2004. Has 36 U.S. and 107 international patents, and his research has been cited more than 24,000 times in the last 10 years.
- Publications: Has co-authored or authored 10 books, 66 book chapters and more than 900 scientific papers.
Polymers are long chains of chemical units known as monomers. The polyethylene used in plastic shopping bags is made up of thousands of ethylene units, for instance.
One of the major challenges polymer chemists have faced, Dr. Matyjaszewski said, is that this chain-building can be over in the blink of an eye. It takes only one second for 1,000 monomer units to link together in a chemical reaction, he said, and that makes it hard to control the synthesis of specialized polymers.
That is where Dr. Matyjaszewski's radical polymerization has made a major difference.
Using his technique, scientists can break the chain-building into tiny increments, "putting it to sleep" and then restarting it, he said. In the process, they can change the kind of monomers or other chemical units being added to the chain, and stretch a reaction that would have taken one second into a precision assembly line that takes a day.
The method has led to some amazing specialty polymers. Several have been commercialized, but most are still in the experimental phase, and could one day play a key role in everything from medicine and cheap energy to environmental cleanup and advanced computing.
One of the products that has been licensed is a sealant for windows in high-rise office buildings.
It has been particularly helpful in the glazing around so-called self-cleaning windows. Those windows are covered with a thin transparent layer of titanium dioxide, which can decompose dirt when it reacts to ultraviolet sunlight, making the window easier to clean.
The problem that arose was that the oil in traditional silicone glazing around those windows could migrate across the surface, contaminating the titanium dioxide layer, he said.
His lab used the radical polymerization process to help develop a soft sealant that would not contaminate the glass, and it's now being marketed by a Japanese firm.
Another commercial use for the process has been to develop thin plastic films for sensitive versions of a lab test known as liquid chromatography.
The test analyzes organic compounds as they flow through a tube that is lined with material that interacts with the different compounds. The Matyjaszewski lab developed polymers for the lining that are so sensitive they can discriminate between molecules that differ by only one amino acid.
Still in development are extremely tiny nanospheres that one day might clean up trichlorethylene, one of the nation's worst pollutants.
Using funds from the National Science Foundation, the lab is trying to perfect plastic-coated iron pellets that could migrate through groundwater and neutralize TCE, a carcinogenic solvent.
Another exciting research area is various kinds of biomedical devices, he said.
The lab is hoping to develop biocompatible polymers that could be used to cover wound openings and speed healing.
It also is working on polymers that might one day help maintain sharp vision in older people. One of the main effects of aging is presbyopia -- literally, elderly eyes -- that stems from the lens becoming stiff and causes near-sightedness.
The eye muscles that control focus are usually fine, Dr. Matyjaszewski said, so if they could be attached to a flexible plastic lens, there is no reason theoretically that people couldn't continue to see well as they aged, without glasses or contacts.
Another possible product: a two-layer polymer that could kill bacteria on countertops and other surfaces in hospitals and nursing homes.
In this case, he said, the lab is exploring "smart materials" that could change shape when the temperature shifts.
That way, there could be an outer polymer layer that kills the bacteria, and then, when the temperature was lowered, that layer would shrink inside the spaces of an underlying polymer layer, expelling the dead bacteria and allowing them to be washed off. Raising the temperature would then bring the bacteria-killing layer back to the surface.
In a way, Pittsburgh can credit martial law and a resemblance to Eastern Europe for drawing Dr. Matyjaszewski to Carnegie Mellon 23 years ago.
He was working in his native Poland in the heady days of the early 1980s, during the rise of the Solidarity trade union and after the election of Polish Cardinal Karol Wojtyla as Pope John Paul II. Then, suddenly, martial law was imposed.
"I thought for my family and myself it would be better to be exposed to different possibilities," he said, and so they moved to Paris, where he taught until a friend told him about an opening at Carnegie Mellon.
"I visited Pittsburgh and at that time it was the named the most livable city in the United States, and Pittsburgh's landscape was very European in nature, and we decided to come here."
The discovery of the atom transfer radical polymerization process in the early 1990s not only opened the door to unusual new products, but made it much easier for people to design complex polymers, including the combination plastics known as block copolymers.
"We can now take undergraduate students and after three hours of training, they can make block copolymers.
"When I was a student it took me three months to make a block copolymer, purifying solvents and doing vacuum distillation, and I had to learn to do glass blowing.
"And after all that, I made one copolymer that was not as good as what one undergraduate makes after three hours today."
First Published October 6, 2008 12:00 am