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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

The Study of Polydimethylsiloxane (PDMS) Coatings for Controlled Drug Release

Gao, Zongming 07 October 2004 (has links)
No description available.
172

Terminal-functionalized poly-t-butyl acrylates via living anionic polymerization

Mollberg, William Carl, 1967- January 1993 (has links)
Block copolymers were made containing peptides coupled to a hydrophobic regions that could be cleaved to obtain a hydrophilic region, similar to globular proteins. These polymers were synthesized by anionic polymerization of t-butyl acrylate followed by coupling with polypeptides. Anionic polymerization allowed control of molecular weight, polydispersity as well as end groups of the polymer. The polymer was terminated with a carboxylic acid or a primary amine, the desired end groups needed to couple this polymer to peptides by conventional peptide coupling reactions. Upon hydrolysis of the esters, the resulting hydrophilic-hydrophobic polymer may be used to act as specific channels through lipid membranes, to increase the solubility of peptides in hydrophilic and hydrophobic solvents or to modify particle growth of inorganic salts.
173

Kinetics and characterization of conducting and insulating polymers by in situ and ex situ techniques

Unknown Date (has links)
The kinetics of polypyrrole, polyaniline, polystyrene and polyurethane syntheses were examined using in-situ techniques. The resulting polymers were analyzed by ex-situ analytical techniques. Comparison of results obtained by different techniques was made. / Polypyrrole was synthesized by the chemical oxidative route. The polymerization using potassium ferricyanide was monitored by Raman spectroscopy, potentiometry and microelectrode analysis. The kinetics were found to resemble exponential decay. The stoichiometry of the polymerization was 2.5 ferricyanide per pyrrole that polymerized and remained constant throughout the experimental period. / The polymerization of aniline by ammonium peroxysulfate was monitored by Raman, potentiometry, calorimetry, quartz crystal microbalance (QCM), conductance measurements, viscometry and visible absorption spectroscopy. QCM and visible absorption spectroscopy were used to probe the nucleation stage. The results showed that polymerization occurred following an induction period. The stoichiometry of aniline polymerization was found to be 1.2 peroxysulfate per aniline consumed. / The induction period of aniline-peroxysulfate system can be reduced by using mixed oxidizers. In the experiment, cerium (IV) was used as co-oxidant with peroxysulfate. A significant decrease in the induction period was observed with 0.01% of cerium (IV). The same effect can also be achieved by adding polyaniline to provide reaction sites for the monomers. / The kinetics of styrene polymerization were monitored by Raman. The decrease in the 1630 cm$\sp{-1}$ aliphatic C=C stretching was interpreted as percent styrene conversion. The 1600 cm$\sp{-1}$ aromatic C=C stretching was used as an internal standard. UV absorption spectroscopy (UV) was used to quantify the amount of styrene in the polymerizing mixture. / IR spectroscopy (IR) and Raman were used to monitor the reaction of modified diphenylmethane-4-4$\sp\prime$-diisocyanate (MDI) and polyether polyol (polyol). The area under the isocyanate IR stretching peak was quantified using the C-H stretching peak as internal standard. In the Raman experiment, the decrease in the 1060 cm$\sp{-1}$ Raman feature and the increase in the 1140 cm$\sp{-1}$ peak were analyzed. / Source: Dissertation Abstracts International, Volume: 54-03, Section: B, page: 1371. / Major Professor: Joseph B. Schlenoff. / Thesis (Ph.D.)--The Florida State University, 1993.
174

Synthesis and properties of novel thermally stable polymers

Kim, Whan-Gi January 1992 (has links)
No description available.
175

Theoretical and numerical study of twist grain boundaries in block copolymers

Zhang, Xusheng, 1980- January 2006 (has links)
No description available.
176

Morphology of block ionomers : a study by SAXS and SANS

Gouin, Jean-Pierre January 1992 (has links)
No description available.
177

Characterization of polystyrene based diblock copolymer micelles

Khougaz, Karine January 1995 (has links)
No description available.
178

X-ray diffraction analyses of synthetic polymers in the 3,3-substituted polyoxetane family and their copolymers

Parris, Juanita M. January 1992 (has links)
No description available.
179

In vitro enzymatic synthesis and degradation of polyhydroxyalkanoates

Nobes, Geoffrey A. R. January 1997 (has links)
No description available.
180

New polymerization reactions : sulfur containing cyclic oligomers and high performance polymers

Ding, Yong. January 1997 (has links)
No description available.

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