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During the second year of this Type B grant, five undergraduate students in engineering and science disciplines contributed to the investigation of fuel additives during 2009-2010.  These students conducted research in the summer and spent 20-30 hrs/week in the lab.  In preparation for graduate and medical school, three of these students presented posters at research conferences.  These students will also present posters at an upcoming symposium in the fall 2010.  Other students, who benefited from PRF funding in past years, have now graduated and entered graduate (2), pharmacy (1), and vet (1) schools.  One of these students, who received a SUMR fellowship from the PRF, has graduated with a BS in chemistry and entered graduate school. 

Over the past several years, we have been investigating a general method for the polymerization of alkenes with polar functionalities.  Given the prevalence of phenols and carboxylic acids, the ability to couple these polar groups with alkenes has a wide variety of possibilities.  These polymerizations have been catalyzed by a strong Bronsed acid, such as trifluoromethanesulfonic acid (TfOH).  This method allows the polymerization of A-B monomers containing an alkene and carboxylic acid, such as 5-norbornene-2-carboxylic acid (NBCO₂H), or monomers with an alkene and a phenol, such as eugenol.  The resulting hydrocarboxylation and hydroalkoxylation reactions can produce polyesters and polyethers, respectively. 

These polymerizations produced monomodal polymers which were soluble in organic solvents, such as tetrahydrofuran and toluene.  Due to the solubility in organic solvents, these polymers have potential to increase the miscibility of fuel blends.  In addition, these phenols also have potential as anti-oxidant groups.  Currently, an undergraduate who is majoring in petroleum and natural gas engineering is evaluating these polymers as fuel additives.  Initial results indicate the resulting polymers are soluble in ethanol fuel blends. 

FTIR spectroscopy of the eugenol polymerizations identified the formation of an ether linkage during the polymerization.  In addition to the methoxy ether absorbance at 1035 cm^-1, an ether absorbance at 1056 cm^-1 was noted after the polymerization.  The phenol OH bending absorbance and the phenol C-O stretch both decreased during the polymerization.

Control experiments were performed to determine if the polymerizations of eugenol were acid catalyzed.  First, the eugenol and TfOH were modified by adding 2,6-di-tert-butylpyridine (DTBP).  DTBP is a hindered base that scavenges acidic protons.  After 24 h, no polymer was detected by gel permeation chromatography (GPC).  Second, when TfOH was replaced with non-protic analogues, such as sodium triflate (NaSO₃CF₃), Na₂SO₄ or sodium dodecyl sulfate (SDS), no detectable amounts of polymer were observed.