April 2001

From Virginia Tech

Manufacturers, researchers urged to monitor polymer synthesis as it occurs

(Blacksburg, Va., April 2, 2001) -- Polymer chemists -- whether they do basic research in academe or product development in industry -- will speed discovery, improve quality control, and reduce waste and byproduct production if they observe what they are doing as they do it.

Virginia Tech Chemistry Professor Timothy E. Long has organized an international symposium on in-situ infrared spectroscopy, to be held April 2 and 3 during the 221st national meeting of the American Chemical Society (ACS) in San Diego.

Long explains that researchers who use in-situ infrared spectroscopy during the synthesis of materials, rather than doing the spectroscopy afterwards, can see the new molecular structures form in real-time.

"Looking at the molecules as the polymer is formed lets you know if the synthesis is successful and if it is generating any byproducts. You can monitor changes in molecular structure and functional groups, observe reaction variables, and determine reaction rates at each stage," says Long. Such information about real-time events will make it easier for scientists to develop new materials with improved processing properties and fewer byproducts, and will allow manufacturers to monitor and control quality.

"Today's advanced products require real-time measurements beyond temperature and pressure," Long explains. "For instance, the composition of a polymeric coating (photoresist) must be well defined in order to optimize the manufacture of computer chips that contain images (lines or circuits) less than 0.1 microns wide or thick. (A human hair can be 75 to 100 microns in diameter.) "Temperature measurements would also not detect an imbalance in composition that can create unwanted byproducts or a flawed material."

Producing and analyzing the material in one step, instead of creating a material then pulling it apart, is also important to the environment. In-situ analysis avoids the creation of waste and byproducts and the use of solvents. "Also, you have your analytical results instantly, rather than having to wait for them," he says.

"With infrared spectroscopy we are using light energy to see how the molecules respond as materials form. The increase or decrease in light absorption will reveal the different molecular structures," Long says.

The two-day symposium, "In-situ Spectroscopy in Monomer and Polymer Synthesis," is being offered by the Division of Polymer Chemistry of the ACS beginning at 8:30 a.m. Monday, April 2. The final presentation will be at 11:30 a.m. Tuesday April 3. The symposium will be in the San Diego Marriott Columbia 1-2 room. There will be a poster session at 6 p.m. Tuesday at the Convention Center Sails Pavilion.

Reach Dr. Long at 540-231-2480 or telong@vt.edu.

This article comes from Science Blog. Copyright 2004

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