Robert T. Mathers
, Pennsylvania State University New Kensington
During the third year
of this Type B grant, four undergraduate students in engineering and science
disciplines investigated the polymerization of olefins. These students
conducted research in the summer and spent 15-30 hrs/week in the lab. Two
of these students will be entering medical school in the next year. During
the last three years of this grant, I have published 3 papers in peer-reviewed
journals with 8 undergraduates as coauthors.
Over the past several
years, we have been investigating methods for polymerizing cyclic and acyclic alkenes.
These include bicyclic alkenes, such as norbornene derivatives, and cyclic dienes,
such as cyclohexadiene. The synthesis and subsequent
polymerization of 1,3-cyclohexadiene (1,3-CHD) from plant oils was investigated
via metathesis and isomerization reactions. The metathesis reaction required
no plant oil purification, minimal catalyst loading, no organic solvents, and
simple product recovery by distillation. After treating soybean oil with a
ruthenium metathesis catalyst, the resulting 1,4-cyclohexadiene (1,4-CHD) was
isomerized with a ruthenium hydride complex. The isomerization reaction was
conducted for 1 h in neat 1,4-CHD with [1,4-CHD]/[RuH] ratios as high as 5000.
The isomerization and subsequent polymerization of the renewable 1,3-CHD was
examined as a two-step sequence and as a one-step cascade reaction. The
polymerization was catalyzed with nickel(II)acetylacetonate/methaluminoxane in
neat monomer, hydrogenated d-limonene, and toluene. The resulting
polymers were characterized by FTIR spectroscopy, differential scanning Calorimetry
(DSC), and thermogravimetric analysis (TGA).