The research presented in this thesis is focused towards applying Surface-Initiated Atom Transfer Radical Polymerization (SI-ATRP) for the synthesis of functional biomaterials. ATRP is a method of living radical polymerization which gives control over the polymer chain length and the end group. SI-ATRP is carried out after immobilization of the molecules that initiate ATRP on surfaces (Gold, Glass, and Silicon). When a surface modified with the initiator molecules is exposed to polymerization solution, the resulting polymer chains are covalently bound; yielding a densely grafted polymer brush. I have developed the SI-ATRP of commercially available oligo(ethylene glycol) methacrylate (OEGMA) monomers to prepare nanoscale poly(OEGMA) coatings that expose PEG chains in high surface density. Protein adsorption for plasma proteins (lysozyme, fibrinogen, and albumin) as measured by XPS shows that, these coatings exhibit remarkable resistance against protein adsorption that depends on the attributes of the monomer. Polymer films thicker than 3 nm are effective in retarding protein adsorption with the level of proteins adsorbed on these films being 99.4% less than that on a bare Silicon surface. I have also evaluated the effects of chain length and end group of the monomers on the kinetics of their polymerization and the wettabilities of the resulting films. Poly(NiPAAm) gels that exhibit a thermal phase transition at 32°C have been widely studied for possible applications in drug delivery systems. I have applied SI-ATRP to synthesize diblock, random, and gradient copolymer brushes of NiPAAm and OEGMA with a goal to obtain polymeric films with an outer biocompatible surface and an inner bulk capable of swelling-deswelling transition. XPS and wetting studies are employed to characterize these coatings. Reactivity ratios in the copolymerization of NiPAArn and OEGMA through SI-ATRP are determined by application of the Mayo-Lewis terminal model of copolymerization. Observed monomer reactivity ratios---r1 (for NiPAAm) and r 2 (for PEGMA, MW 300)---are 0.07 and 3.85, respectively. Finally, the techniques developed above are applied to create a nanoscale device capable of photothermally triggered drug release. Nanoshell-PNiPAAm hybrids are synthesized by SI-ATRP of NiPAAm on gold nanoshells and characterized by XPS and TEM.

Emission at the Na D lines has previously been observed from the intersection of crossed effusive beams of K and NaCl irradiated by a dye laser at wavelengths form 590nm to 735nm. The three beam signal is attributed to direct photoexcitation of KClNa transition region species. Further interpretation of these experiments is hampered, however, by broad translational and internal energy distributions of reacting partners. Supersonic beams of K and NaCl, both seeded in argon, were developed in order to reduce the distribution of translational and internal energies. It was hoped that insight into the reaction dynamics of the K+NaCl system would be revealed by the difference in collision energy between crossed effusive beams and crossed seeded beams. In addition, the rotational broadening of the K$\sb2$B$\sp1\Pi\sb{\rm u}$-X$\sp1\Sigma\sb{\rm g}\sp{+}$ spectrum collapses on cooling and therefore "artifact-clean" frequencies could be probed by the laser. Extensive characterization studies of the seeded beam sources were carried out. Mean velocities of K and NaCl were measured to be 1.3 $\times$ 10$\sp5$ and 1.1 $\times$ 10$\sp5$ cm/sec, respectively. Measurements of the rotational and vibrational energy distributions of K$\sb2$ present in the potassium beam reveal a rotational temperature of 12 $\pm$ 1$\sp\circ$K and vibrational temperature of 77 $\pm$ 13$\sp\circ$K. Time of flight experiments demonstrate a translational temperature for NaCl and K beams of 170$\sp\circ$K and 12$\sp\circ$K, respectively. Significant three beam emission at the 589.0nm Na D line is observed at the intersection of crossed seeded reagent beams of K and NaCl irradiated by a dye laser from 610nm to 750nm. This three beam signal is comparable to that previously observed with effusive sources. However, contrary to expectations the photoluminescence of the K beam at 589.0nm when laser excited in the region 610-750nm was much larger than for an effusive source. The seeded source potassium photoluminescence at 589.0nm is an order of magnitude larger than the seeded source three beam signal. In contrast, the three beam signal with an effusive K beam is substantially the largest signal in that system. Nevertheless, the narrow energy distribution of these supersonic sources and their ability to change the collision energy makes them very useful for further probing of the KClNa transition region species.

Triscycloproparenes 1 and 2 were synthesized by treating the Diels-Alder adducts of 1-bromo-2-chlorocyclopropene and either hexaradialene (3) or hericene (4) with potassium t-butoxide. New cycloproparenes 5 and 6 were also isolated using this approach.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) The thermolysis of cyclopropa (b) naphthalene with C$\sb{60}$ was investigated and was found to yield a new Fullerene adduct. The biradical addition was also performed with $\sp3$He labeled Fullerene, and the product (7) was studied by $\sp3$He NMR.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) Silver (I) catalyzed reactions of several cycloproparenes were also investigated. In the absence of nucleophilic protic solvents or other reactants, benzocyclopropene (and its derivatives) could be dimerized to yield linearly fused six-membered rings as illustrated by the reaction of cycloproparene 8. Further aromatization of the dimers could be achieved (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) using DDQ in benzene. This technique was also employed with biscycloproparenes such as 11 and the new triscycloproparenes to obtain ladder polymers and more intricate nonrandomly cross-linked polymers.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI)

Experiments using the laser vaporization technique for production of metal clusters have been performed. The reactions of neutral metal clusters with various gases have been studied using a fast flow reactor. Dramatic reactivity variations were observed which depended on cluster size, metal, and reactant. A laser vaporization disc source has been developed for the study of semiconductor clusters. Some preliminary studies on neutral germanium and silicon clusters were performed. Their ionization potentials have been bracketed and the clusters were found to fragment by a fissioning process and to have long lived (100 nanoseconds) excited electronic states. A detailed study has been undertaken into carbon clusters. Laser synthesis of astrophysically important polyyne molecules such as H-C-(C-C)$\sb{\rm 2n}$-N has been done. Chains containing up to 22 carbon atoms are formed in a vaporized carbon and reactant gas plasma. A photophysically stable and chemically inert cluster, C$\sb{60}$, has been discovered and hypothesized to have the structure of a truncated icosahedron. All even clusters in the 60 atom size range were found to be inert to highly reactive gases, while odd clusters readily reacted. The results are consistent with a whole series (30-90 atoms) of closed cage-like structures. Closure of even clusters only is possible via the inclusion of twelve pentagons into a hexagonal network. Odd clusters show neither the photophysical nor chemical stability of the even clusters. A mechanism for the formation of spherical soot particles has been developed. Stable organometallic complexes of the formula C$\sb{\rm 2n}$M (20 $<$ n $<$ 40 and M = La, Ba, Sr, Ca) have been laser synthesized. The dominant complex observed was C$\sb{60}$M$\sp+$. These species are photophysically stable, chemically inert, and no C$\sb{\rm 2n}$M$\sb2$ species were detected. The ultraviolet and visible absorption spectrum of C$\sb{60}$ has been measured. Because excited electronic states are not expected to live long in a molecule of this size, a unique spectroscopy independent of excited state lifetime was developed. Predissociation spectroscopy was performed on the cold van der Waals complexes C$\sb{60}$--CHCL$\sb2$ and C$\sb{60}$--benzene. A single sharp (50 cm$\sp{-1}$ wide) absorption band was found at 3860 A and 3863 A for the two complexes respectively. This peak is tentatively assigned to the 0-0 band of the lowest $\sp1$T$\sb{\rm 1u}$ $\gets$ $\sp1$A$\sb{\rm g}$ (LUMO+1 $\gets$ HOMO) transition of a truncated icosahedral carbon shell structure.

The Statistical Associating Fluid Theory (SAFT) equation of state is a statistical mechanics based equation of state based on Wertheim's theory of associating fluids. Since SAFT is a statistical mechanics based equation of state, it is possible to include more physics in the model to make it more predictive. In this work we show the versatility of SAFT by applying it to monomers and polymers and include dipolar interactions in SAFT. SAFT is used to model phase equilibria in long chain-short chain alkane mixtures. It is shown that SAFT accurately models phase equilibria in these systems even when there is a large disparity between the chain lengths of the two alkanes. We then use the statistical associating fluid theory (SAFT) to model liquid-liquid phase equilibria in solutions of linear low density polyethylene (LLDPE) with hexane, heptane and octane. The effect of temperature, pressure, polymer concentration and polymer molecular weight on phase separation is studied. Finally, the effect of polydispersity on cloud point is also considered. SAFT results are compared with experimental data by de Loos et al. [1]. It is shown that SAFT can model the phase behavior of the polymer in different solvents at various state conditions with a single adjustable parameter. The applicability of SAFT to these monomers and polymers shows that it is a versatile thermodynamic model. We propose an algorithm for calculating phase equilibria of polydisperse polymer systems using the SAFT equation of state. The algorithm is formally exact and the computation time is independent of the number of pseudo-components used to represent the polymer molecular weight distribution. The algorithm makes use of the form of the SAFT equation of state and simplifications resulting from it to simplify the flash calculations. Distinctive features of the phase diagrams of polydisperse systems are illustrated by calculating the cloud point and shadow point curves of polyethylene solutions in ethylene using the algorithm proposed in this work. We present results from molecular simulation and statistical mechanics based theory for dipolar hard sphere chains and dipolar Lennard-Jones (LJ) chains. We consider the chains with dipoles on alternate segments. The equation of state is obtained by applying Wertheim's associating fluid theory in the total bonding limit to a mixture of non-polar and dipolar segments. It is shown that the theory developed here is in very good agreement with computer simulation. This theory simultaneously accounts for chain and dipolar effects and can handle multiple dipolar sites in a molecule. This is demonstrated by generalizing the theory to mixtures and applying it to dipolar monomers and copolymers. The theory accurately predicts the phase behavior of real dipolar fluids.

Using perfluoropolyether as the solvent, cutting of pristine SWNT has been achieved by extensive ozonolysis with 80% carbon yield at room temperature. The intense disorder mode in the Raman spectra of ozonated SWNT indicates that extensive reaction with the sidewalls of SWNT occurs during ozonolysis. AFM provided a measure of the extent of the cutting effects. Monitoring of the evolved gases indicates CO2 was produced during the ozonolysis process with a dependence on both system pressure and temperature. During heating, FTIR analysis of gases released indicates carbon oxygen groups on the sidewalls of SWNT are released as CO2. Room temperature ozonolysis of fluorinated SWNT and phenol-sulfonated SWNT have also been studied in PFPE. For fluorinated SWNT, etching at the end caps has been demonstrated to be the dominating effect during this process. The improved suspension in 96% sulfuric acid after ozonolysis enables the cutting by ammonia peroxydisulfate without defluorination with a hydrazine treatment. PS-SWNT was found to be effectively cut by ozonolysis in a water suspension with preserved water solubility. Controlled by the electron dosage, a high energy electron beam (3MeV) has been demonstrated to cut ozonated SWNT. Besides ozonolysis, 700&deg;C has been shown an optimal temperature to cut F-SWNT by pyrolysis in an argon atmosphere.

The ability of an artificial surface to resist the non-specific adsorption of proteins in biological solutions greatly improves its biocompatibility---a desirable property to overcome many problems across the biomedical and biochemical processing areas. This thesis demonstrates the effectiveness of surface-initiated atom transfer radical polymerization for the synthesis of hydrophilic, protein resistant coatings with controlled thicknesses in the nanoscale regime (1--100 nm). The strategy uses the surface initiated atom transfer radical polymerization of commercially available oligo(ethylene glycol) methacrylate monomers with different chain lengths and either hydroxyl or methoxy group terminations. This thesis evaluated the effects of chain length and end group of the monomers on the kinetics of their polymerization and the protein resistance of the resulting films. Protein adsorption for plasma proteins (lysozyme, fibrinogen, and albumin) as measured by XPS shows that, these coatings show remarkable resistance against protein adsorption that depends on the attributes of the monomer.

The technique of infrared kinetic spectroscopy has been used to study the reaction of the propargyl radical (C3H3) with nitric oxide (NO). The overall rate constant at the high pressure limit for the reaction was determined to be 1.09 +/- .28 * 10-11 cc molec-1 s -1 at 296 K. The reaction has an apparent negative activation energy for temperatures between 195--473 K and its rate constant is pressure dependent at 195 K and 296 K. At these temperatures the mechanism is believed to involve adduct formation. The establishment of an adduct equilibrium is not observed at higher temperatures, however. Instead the reaction is thought to form final stable products. A search was carried out for several possible reaction products including HCN, HCCN, HCNO, HCCH, HNC and H2CN. Several of these species were observed and their yields determined. These species were at most produced in 5% yield and are therefore not a major product channel. An alternative sources of these species are reactions between NO and other photolysis products. A possible explanation for the failure to observe any smaller molecular products is that the adduct does not dissociate at high temperatures and instead, rearranges to a stable isomer of C3H 3NO. Transient IR laser spectroscopy near 3100 cm-1 was used to observe the nu1 and nu13 transitions of the allyl radical, with their band origins found to lie at 3113.9779(3) cm -1 and near 3110.5 cm-1, respectively. Detailed assignment and analysis of the nu1 transition identified over 1100 transitions, and yielded improved values for DeltaK and phiK ground state centrifugal distortion constants, as well as a new set of excited state (nu1 = 1) rotational and centrifugal distortion constants, in addition to determining the band origin. Transitions involving states with quantum number up to Ka = 11 and N = 27 were identified. Strong perturbations were found in the excited state, included global perturbations of the Ka' = 3 branch, extensive perturbations in the Ka' = 2 and 4 branches, and very localized perturbations in the Ka' = 6 branch. The K a' = 9 and 10 branches appear to be the most perturbed. Possible sources for these perturbations are discussed.

An unique linear aliphatic trisazoalkane was synthesized. Its thermolysis proceeded stepwise to yield seven fragments, with an overall reaction enthalpy of -93.6 kcal/mol, 66.6 kcal/mol lower than that for azo-t-butane. Due to the stepwise feature, the difference in overall reaction enthalpy resulted in only an 8.6 fold rate increase for the trisazoalkane relative to azo-t-butane at 153.46&deg;C. Photolysis of a novel cyclic azimine obtained during the synthesis of the trisazoalkane yielded a highly strained triaziridine and an unusual triazane. The triaziridine rapidly reverted to the azimine with a rate constant of 2.05 x 10-4 s-1 at 24.4&deg;C. Arylmethylenecyclopropanes with para azo, azoxy and other related N-containing substituents were synthesized to study radical stabilizing effects. The order of increasing radical stabilizing ability was determined to be -N(O)=NBu-t, -N3, CH=NBu-t, -N=NBu-t, -NH2, -CH=NOMe, -CH=NNMe 2, -N=N(O)Bu-t, -N=NPh and -CH=N(O)Bu-t. The last three groups, azoxy, nitrone and phenylazo, were the best non-ionic radical stabilizers ever studied. The large rate enhancements in the thermal rearrangement resulted from radical stabilization through spin delocalization by the para-substituents in the transition state. A cumyl type 1,3,5-trisazoalkane and its monoazo, para-bisazo and meta-bisazo analogs were synthesized. Thermolysis of C3 and C4 followed a stepwise mechanism; that is, the two azo groups decomposed sequentially. Mathematical models were developed for analyzing the kinetics data. The rate constants for these azoalkanes increased statistically with the number of -N=N-groups. In addition to the stepwise mechanism, the para-bisazo compound also decomposed concertedly to a quinodimethane. To demonstrate that the 1,3,5-triazoalkane could serve as a radical initiator, different trapping products were made by thermolysis of the 1,3,5-trisazoalkane in the presence of PhSH and nitroxyl radicals. In the binary system of C4 and TEMPO, low polydispersity (1.13) was obtained for polystyrene.

Composite polymer particles were made of two or more polymers. If these polymers are incompatible, the particles after polymer phase segregation exhibit complex morphologies which determine their properties and applications. Such particles may have applications in both academia and industry. In this work, polystyrene (PS)/ poly(2-cinnamoyloxyethyl methacrylate) (PCEMA) and poly(acetyloxyethyl methacrylate) (PAEMA)/PCEMA composite polymer particles are prepared by the evaporation of toluene from PS/PCEMA/toluene and PAEMA/PCEMA/toluene droplets dispersed in an aqueous solution containing surfactants. The surfactants used for the two systems are poly(glyceryl methacrylate)100-block-poly(2-cinnamoyloxyethyl methacrylate)15 (PGMA100-b-PCEMA15) and poly(glyceryl methacrylate)300-block-poly(2-cinnamoyloxyethyl methacrylate-ran-acetyloxyethyl methacrylate)37 (PGMA300-b-P(CEMA-ran-AEMA)37), respectively, for the PS/PCEMA and the PAEMA/PCEMA systems. The morphologies of the PS/PCEMA and PAEMA/PCEMA composite particles are analyzed by transmission electron microscopy (TEM), atomic force microscopy (AFM), and dynamic light scattering (DLS). The results indicate that the particles are polydisperse and of nanometer size. For the PAEMA/PCEMA particles, the preferred morphology is hemisphere, while for the PS/PCEMA system the morphology is a mixture of acorn and occluded core-shell. Based on Gibbs free energy theory, and knowing the corresponding surface tensions and interfacial tensions, the thermodynamic equilibrium morphologies for both kinds of composite particles were found. Due to the uncertainty during measurements and calculations, and the influence of kinetic factors, the theoretical predictions agreed only partially with the experimental observations. / Thesis (Master, Chemistry) -- Queen's University, 2008-08-27 12:16:37.142