Chemistry at Aquinas College

Li-Heng Chen, Ph. D.

Emeritus Professor of Chemistry
(616) 632-2187
AH 325


Research Interests:

I am interested in studying the chemical conversion of scrap rubber tires to useful ion exchange polymers by utilizing the well-established technologies of functionalizing styrene rings in polymer matrix. The use of ion exchange polymers to remove and recover metal ions is an important environmental remediation technique in industrial wastewater treatment. The most commonly used ion exchangers are polystyrene-based cross-linked copolymers. Currently 70% of synthetic tires made from styrene-butadiene rubber (SBR) are discarded in landfills.

Many polymers have both hydrophobic and hydrophilic terminal groups. Modification of these groups should result in changing the solubility and expanding the application of the polymers. A large proportion of the simple reactions in organic chemistry have never been tried on commercially available polymers. One of my other research goals is to explore these reactions; for example, esterification of the sulfate end of amberlites or hydrolysis of polyvinylpyrrolidone followed by reacting with diepoxides.

Another of my interests is in obtaining the complete vibrational spectrum of compounds (especially nitrogen oxides, polymers, and superconductors) by means of Fourier transform infrared spectrometry and laser Raman spectrometry, and then doing the vibrational assignment of the spectra and force constant calculation to more fully understand the vibrational motion and bonding of the molecule.

The addition of nitric acid changes the color of an egg. Do other acids produce similar effects on eggs? Will egg white and egg yolk react differently, perhaps giving two different colors? What is the minimum concentration of acid which will result in the color change? Does the color change more quickly under certain conditions? This project should produce a better understanding of the mechanism of the observed reaction.


  • Ph.D., Texas A&M University
  • M.S., State University of New York at Stony Brook
  • B.S., National Taiwan University