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Molecular dynamics simulations are used to examine the response of monolayers composed of alkyne chains, which contain diacetylene moieties, to compression and shear. The simulations show that both compression and shear result in cross-linking, or polymerization, between chains.

Tris(1,2ethanediolato)tungsten(VI), [W(eg)3] reacts with methylamino-N,N-bis(2-methylene-4,6-di-methylphenol) and methylamino-N,N-bis(2-methylene-4-methyl-6-tert-butylphenol) to form oxotungsten complexes. The prepared oxotungsten(VI) complexes can be activated by Et2AlCl to catalyze ring-opening metathesis polymerization of norbornene.

The first electron paramagnetic resonance (EPR) spectroscopic results that explain the nature of the diradical species involved during Bergman cyclization of bis-ortho-diynyl arene (BODA) polymerization is reported. A model compound, 1,2-bis(phenylethynyl)benzene, is used to investigate the polymerization mechanism, and aromatic radical intermediates are found to be stable indefinitely at room temperature.

The thermal and thermo-oxidative degradation of polystyrene (PS) and PS-clay nanocomposites are investigated using thermogravimetry and differential scanning calorimetry (DSC). The kinetic analysis depicted that the processes of degradation and relaxation have larger activation energies in the clay composite than in virgin PS.

The Si29 and C13 cross-polymerization (CP)/ magic-angle spinning (MAS) NMR spectroscopy technique is employed to characterize the surface species on silylated silica with different degrees of dehydroxylation, when it is modified with gamma-aminopropylalkoxysilanes from the gas phase at various deposition temperatures.

Studies done to demonstrate that M-TTR (monomeric variant of transthyretin) amyloidogenesis at low pH is a complex, multistep reaction whose kinetic behavior is incompatible with the expectations for a nucleation-dependent polymerization is reported. Results of the study suggest that amyloid formation by M-TTR under partially denaturing conditions is a downhill polymerization, in which the highest energy species is the native monomer.

Addition of arylithium followed by ring closure with boron trifluoride produced a blue-emitting ladder-type pentaphenylene. Bromination followed by reductive polymerization with nickel (0) gave new high molecular mass polymers, which show efficient blue emission with a very small Stokes shift.

Laterally varying thickness gradients of poly(acrylic acid) (PAA) were formed by Zn(ll)-catalyzed electropolymerization of acrylic acid (AA) in the presence of an in-plane electrochemical potential gradient applied to Au working electrodes. PAA thickness gradients have been mapped onto Au electrodes through electropolymerization of acrylic acid using both static and dynamic electrochemical potential gradients, according to the description.

The coordinative/insertive stereoregular homopolymerizations and copolymerizations of styrene and methyl methacrylate mediated by a highly active single-site organotitanium catalyst are described. A new mechanism involving a sequential conjugate addition steps to explain the copolymeric results are suggested.

Highly porous emulsion-templated materials are synthesized by polymerization of concentrated CO2-in-water emulsions. The findings indicate that the emulsion stability is strongly affected both by the nature of the surfactant and by the viscosity of the aqueous continuous phase.

The synthesis of random medium-size ribonucleic acid (RNA) analogues with mixed sequences in ice eutectic phases that are produced when dilute solutions of activated monomers and catalysts are frozen and maintained at -18 degree Celsius for a period of 38 days is described. The results suggest that the eutectic phases in ice are suitable for the random RNA analogue polymerization that will yield pools of medium-size polymers.

The reactions of vinyl chloride (VC) with representative late metal, single-site olefin dimerization and polymerization catalysts are investigated. Termination of chain growth by beta-Cl eliminations is the most significant obstacle of metal-catalyzed insertion polymerization of VC.

The detailed catalytic behavior of Ti complexes with fluorine-containing phenoxy-imine celate ligands for the polymerization of propylene is reported. The steric bulk of the substituent ortho to the phenoxy oxygen plays a decisive role in achieving high syndioselectivity for the chain-end controlled polymerization.

High-throughput approaches offer significant advantages over more conventional methods of catalyst discovery. For the first time, a new catalyst for olefin polymerization is discovered through the application of fully integrated high-throughput primary and secondary screening techniques supported by rapid polymer characterization methods.

The effect of variables such as shape template size, porogen composition and percentage, content of cross-linking monomer, and polymerization temperature on the properties of uniformly sized 3-[micro]m porous poly(glycidyl methacrylate-co-ethylene dimethacrylate) beads prepared by the staged templated suspension polymerization technique has been studied. The porous properties of the beads including surface morphology, pore size distribution, and specific surface area have been optimized to obtain highly efficient stationary phases for normal-phase HPLC. A column packed with diol stationary phase obtained by hydrolysis of poly(glycidyl methacrylate-coethylene dimethacrylate) beads affords an efficiency of 67 000 plates/m for toluene using THF as the mobile phase. The retention properties and selectivity of the diol beads are easily modulated by changes in the composition of the mobile phase. The performance of these beads is demonstrated with the separations of a variety of polar compounds including positional isomers, aniline derivatives, and basic tricyclic antidepressant drugs.

The nanostructured inorganic host altered the diacetylene polymerization behavior, and the resulting nanocomposites show unique thermo-, mechano-, and solvate-chromic properties, and polymerization of the incorporated surfactants resulted in polydiacetylene (PDA)/silica nanocomposites. The nanostructured inorganic framework serves to protect, stabilize, and orient the polymer, mediate its performance, and provide sufficient mechanical and chemical stability to enable integration of conjugated polymers into devices and microsystems.

Research has been conducted on the dietary flavonoid quercetin. Results demonstrate that quercetin inhibits microtubule polymerization and depolymerizes microtubules made from purified tubulin.

Ladderlike polysiloxane is normally divided into two categories, oxygen-bridged polysiloxane and organo-bridged polysiloxane and synthesis of soluble ladderlike polyphensylsilsesquioxane using equilibrium process is generally followed. A different soluble aryl amide-bridged ladderlike polymethylsiloxane was synthesized using stepwise coupling polymerization.

Synthesis of novel organoarsenic polymers, poly(vinylene-arsine)s, by a free-radical alternating copolymerization of phenylacetylene with cyclooligoarsines as an atomic biradical equivalent is explained. Reaction mechanism suggests that the addition of the arsenic radical to phenylacetylene is a rate-determining step in the coplymerization.

The reaction mechanism of the copolymerization reaction of carbon dioxide and epoxides in presence of a chiral (salen)chromium-chloride catalyst is investigated. In situ measurement at 80 degrees celsius and 58.5 bar pressure demonstrated that the mechanism for the (salen)Cr(super III)-catalyzed asymmetric ring-opening (ARO) of epoxides displays a squared dependence on [catalyst], whereas the rate of carbonate chain growth leading to copolymer or cyclic carbonate formation is linearly dependent on [catalyst].

Research has been conducted on the heterometallic compounds from the orthorhombic family. The synthesis and structures of these compounds have been carried out and their electronic structures have been investigated and are discussed.

The synthesis of chiral aluminum and yttrium alpoxides and their applications for lactide polymerization is reported. Homochiral (R)-4 was found to exhibit excellent stereocontrol in a range of polymerization.

Vanadium phthalocyanine and porphyrin complexes, in conjunction with methylaluminoxane (MAO) or EtAl[Cl.sub.2] cocatalyst, have been found to catalyze the homopolymerization of ethene. In addition, the copolymerization of ethene with propene and 1-decene was achieved with the vanadium phthalocyanine complex and MAO. Nickel phthalocyanine complex was also found to catalyze the polymerization of ethene in the presence of MAO. However, only dimerization was observed when EtAlpCl.sub.2] was used as the cocatalyst. Key words: phthalocyanine, porphyrin, polymerization, copolymerization, ethene, propene, 1-decene.

Alternating copolymerization of fluorinated olefins ([C.sub.n] [F.sub.2n + 1])[(C[H.sub.2]).sub.m]CH=C[H.sub.2] (1) and carbon monoxide was carried out using cationic Pd(II)-(R,S)-BINAPHOS complexes (2) as catalysts. To obtain polymeric products sufficiently, existence of at least two methylenes in 1 were essential (m [greater than or equal to] 2). The products thus obtained formed polyspiroketal (4) rather than polyketone (3), the structures being determined by solid- and solution-state NMR and IR analyses. The water contact angle was 108[degrees] for a sample of 4f when it was casted on a glass surface from [C.sub.6][F.sub.6] solution. Key words: copolymer, fluoroalkene, carbon monoxide, palladium, contact angle.

Two- and three dimensional covalent titanium-organic networks (CMON) are assayed for ethylene and propylene polymerization activity through the addition of methylaluminozane. CMON are mediocre Ziegler-Natta catalysts that generate polydisperse, linear polyethylene and atactic polypropylene.

Research is done on aluminum amidinate species, found to be active in ethylene polymerization, which have been studied using a variety of computational methods, including semiempirical (AMI), Hartree-Fock and density functional theory type calculations, and first-principles MD simulations. In conclusion, the study clearly indicates that it is necessary to model the real catalyst, including bulky substituents if present, to arrive at a proper understanding of structure and activity.

Research elucidates aldol addition reactions involving titanium enolates of N-acyloxazolidinethiones and N-acylthiazolidinethiones, which proceed with high selectivities and yields. Data indicate that the reactions can accommodate a variety of aldehyde structure type compounds such as Evans syn aldol, and non-Evans syn aldol products.

The nanoparticles were incorporated successfuly into the polymerized CVDAV (PCV) and retained their size and quantum size effect. The synthesized CVDAC is soluble in polar solvents such as methanol, ethanol, acetone and chloroform and also in aromatic solvents such as benzene and toluene but is soluble in paraffinic solvents.

A study was conducted that investigated the mechanism of copper(I)-mediated 'living' atom-transfer radical polymerization (ATRP) in aqueous media. It was shown that the ATRP apparent rate constant for polymerization of methoxycapped oligo(ethylene glycol) methacrylate (OEGMA) in water [k(sub p)(super app)] at room temperature correlates with the redox potential (E1/2) of the copper complexes.

The use of microtransfer molding technique (microTM) for the rapid, high-fidelity replication of complex 3-D polymeric master structures that have extremely high aspect ratios or reentrant features, which are created via multiphoton absorption polymerization (MAP) is demonstrated. The effective combination of microTM and MAP create arrays of complex 3-D microstructures into a parallel lithographic process.

A unique polymerization reaction involving alkylsilanes and water catalyzed by gold nanoparticle surfaces is reported. A simple reflux reaction is used to prepare a large quantity of siloxane, nanowires, filaments, and tubes.

The synthesis of new alpha-aldehyde-terminated poly(methoxyPEG)methacrylates obtained through Cu(I) mediated living radical polymerization and their application for the conjugation of proteins using lysozyme as a model is presented. This method appears to be general and may be extended to many proteins and most of the monomers amenable to metal-catalyzed living radical polymerization.

Organolanthanide-catalyzed synthesis of phosphine-terminated polyethylenes is presented. The diphenylphosphine is shown to be an efficient chain transfer agent in organolanthanide-catalyzed ethylene polymerization, yielding phosphine-terminated polyethylenes.

The synthesis of peptide dendrons, the formation of cross-linked hydrogels, the analysis of hydrogel physical properties, and the use of these biomaterials to seal a corneal incision are reported. A new in situ polymerizing hydrogel is reported that gels within a few minutes from the multiple thiazolidine linkages formed between the cysteine residues of the dendron and the poly(ethylene glycol) macromers.

A rapid and convenient seeding method to chemically synthesize bulk quantities of microns-long, 60-90 nm thick nanofibers of polypyrrole is described. The findings have a potential to be leveraged beyond conducting polymers to embrace the broad class of precipitation polymerization reactions.

New neutral ansa-metallocene allyl complexes are synthesized based on the [Flu-CMe2-Cp](super 2-) ligand for syndiospecific propylene polymerization. Allyl lanthanide complex was used as the catalyst for the reaction.

The initial observation of photodissociation of a Fe-Cp bond by the use of an appropriate anionic initiator, and the discovery of a new photolytic living anionic ROP method is presented. This new photolytic anionic ROP method offers opportunities by permitting living anionic polymerization of strained metallocenophones and block copolymerizations with monomers.

The microchannel reactor is designed for controlled polymerization with the help of a microfluidic system. The conclusion suggests that continuous microreactor can be used to produce libraries of materials for direct integration with high-throughput processing and characterization methods.

A unique and simple method is reported for stabilizing surface micelles of a low molecular weight surfactant 11-acryloyloxyun-decyltriethylammonium bromide (AUTEAB) through in situ intramicellar polymerization initiated by gamma-irradiation on mica surface. A unique and feasible method to stabilize surface micelles by in situ intramicellar polymerization initiated by gamma-irradiation, is developed.

A new synthesis strategy to allow unprecedented flexibility and control in dispersion polymerization is described. Monodisperse polymeric beads of micrometer-sized diameters have many important applications as separation media, ion-exchange beads, toners, coatings, calibration standards, and in medical diagnostics.

Ethylene-styrene copolymers have received great attention due to their impressive viscoelastic behaviour, mechanical properties and compatibilities with other polymeric materials. The development of homogeneous single site polymerization catalysts led to a resurgence of interest in this field and present binuclear organotitanium catalyst not only effects styrene homopolymerization with high activity, but also is the first catalyst that can produce ethylene.

The use of chelating diborane or related compounds as activators in olefin polymerization is explored. It is found that the chelated weakly coordinating counteranions (WCA) derived from compounds present advantages in ethylene polymerization over trityl activators partnered with mononuclear WCA.

The first example of hydrogen bond templated adlayer polymerization on self-assembled monolayers (SAMs) is demonstrated. The combination of labile adlayer chemistry with crosslinkable monomers may provide a route to single monolayer two-dimensional polymer sheets that can be readily patterned using existing lithography techniques and released into solution.

Organic cations can induce polymerization of monomers in the liquid phase. Ion-molecule reactions in the gas phase can lead to the formation of large ions, clusters, and even macroscopic particles.

Mainly the saturated fluoropolymers have great amount of thermal and chemical consistency, low surface power, increased insulating capability, minimal refractive index and dual electric consistency. Moreover, the monomer vinylpentafluorocyclopropane is planned and synthesized in such a manner that it creates polymers consisting of polarized double bonds, which cannot be entered via radical polymerization of fluorinated dienes or dehydrofluorination of additional fluoropolymers.