Non-polar phase selective solubility of modified poly(4-n-alkylstyrene) supports
can be measured using fluorescent dyes as catalyst surrogates with thermomorphic and
latent biphasic systems. By modifying the solvent compositions in heptane/ethanol and
heptane/N, N-dimethylacetamide, increased non-polar phase selective solubility of
modified polystyrene supports can be attained. Likewise, by varying the structure and
length of the pendant alkyl chain, an increase in non-polar phase selective solubility is
measured. These heptane soluble polymer supports can be useful for applications
involving heptane soluble polymer-bound reagents and catalysts.
Various polar and non-polar polymer supports were synthesized with an attached
solvatochromic catalyst surrogates to determine the solvent accessibility of the supported
species in pure and mixed solvents. The results of these studies indicate that in pure
solvents, the influence of both polar and non-polar polymer supports on the solvent
microenvironment of these polymer-supported probes is minimal. In mixed solvent
systems, a polymer-like solvent microenvironment is measured in solvent mixtures
comprised of solvents the polymer has unfavorable interactions. Poly(4-n-alkylstyrene)
and internally functionalized polyisobutylene supports are two such polymer supports that exhibit this behavior. For terminally functionalized polymers in mixed solvents, the
solvatochromic behavior does not indicate a collapsed structure. In mixed solvents,
there is minimal influence of the polymer support on the solvent microenvironment of
these terminally functionalized polymers.
The application of soluble polyisobutylene supported copper complexes in the
ATRP polymerization of styrene was investigated. Using the difference in solubility of
the product polystyrene and the polyisobutylene copper complex in heptane, a
solid/liquid separation of the soluble copper complex from the solid product was
achieved. The results of these polymerizations indicate that the polyisobutylene copper
complex behaves exactly like a low molecular weight copper complex in terms of
control over molecular weight and molecular weight distribution. After the
polymerizations, the polyisobutylene complexes could be separated as a heptane solution
and recycled in multiple polymerizations of styrene.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-1256 |
| Date | 15 May 2009 |
| Creators | Hamilton, Patrick Neal |
| Contributors | Bergbreiter, David E. |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | electronic, application/pdf, born digital |
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