| dc.description.abstract | Using carbocationic polymerization, a series of novel polyvinylether polymers and
copolymers were synthesized and characterized. A series of polysiloxane copolymers
containing polymer grafts possessing Triclosan moieties (PTVE) were synthesized using
living carbocationic polymerization followed by hydrosilylation and investigated for
potential application as environmental friendly coatings to control biofouling on marine
vessels and biomedical devices. Copolymers possessing a relatively low molecular weight
polysiloxane backbone and relatively high PTVE content exhibited very high reductions in
biofilm retention for S. epidermidis and moderate reductions for C. lytica and C. albicans.
In the second example, a novel monoallyl-functional initiator that was capable of
producing very fast initiation of the living carbocationic polymerization of chloroethyl
vinyl ether was synthesized and characterized. The monoallyl-functional polymers were
used to produce a series of block copolymers containing blocks of polyquaternary
ammonium compounds and polydimethylsiloxane (PDMS-b-PCVE-b-PQ) using
hydrosilylation followed by quaternization with an n-alkyldimethyl amine. The PDMS-bPCVE-b-PQ copolymers in solution showed very high antimicrobial activity toward E. coli
and S. aureus when the n-alkyl chains attached to the nitrogens of the quaternary
ammonium compounds are consisted of 12 - 14 carbons and 14 - 16 carbons, respectively.
In the third example, a novel, highly brominated polymer was synthesized from pentabromo-6-ethoxybenzene vinyl ether (BrVE) using cationic polymerization. The
thermal and rheological properties of the polyBrVE (PBrVE) were compared to a
commercially available oligomeric brominated flame retardant, poly(pentabromobenzyl
acrylate) (PBrBA). In addition, polymer blends based on polybutylene terephthalate (PBT)
were prepared with the two brominated polymers and the thermal stability, mechanical, and
rheological properties compared. The use of PBrVE resulted in lower melt viscosity and
better compatibility in blends with PBT which would be expected to provide enhanced
processability with regard to creating injection molded parts with relatively thin walls, such
as those encountered in the electronics industry. Finally, a process was developed to obtain
vinyl ether-functional monomers containing fatty acid pendent groups directly from
soybean oil (SBO) using base-catalyzed transesterification. Moreover, a carbocationic
polymerization process was developed for the vinyl ether monomers that allowed for high
molecular weight polymers to be produced. Compared to SBO, which possesses on average
4.5 vinyl groups per molecule, the polyvinylethers based on the soybean oil-derived vinyl
ether monomers (polyVESFA) can possess tens to hundredss of vinyl groups per molecule
depending on the polymer molecular weight produced. As a result of this difference,
coatings based on polyVESF A were shown to possess much higher crosslink density at a
given degree of functional group conversion compared to analogs based on conventional
SBO. In addition, the dramatically higher number of functional groups per molecule
associated with polyVESF A results in gel-points being reached at much lower functional
group conversion, which was shown to dramatically reduce cure-time compared to SBO based analogs. | en_US |
