Octyl Methacrylate Research Articles

Superhydrophobic coatings on textiles based on novel poly(perfluoro-tert-hexylbutyl methacrylate-co-hydroxyethyl methacrylate) copolymer deposited from solutions in supercritical carbon dioxide

A novel 6,6,7,7,8,8,8-Heptafluoro-5,5-bis(trifluoromethyl)octyl methacrylate monomer is synthesized. Corresponding homopolymers and copolymers with hydroxyethyl methacrylate are obtained by means of radical polymerization in supercritical carbon dioxide using azobisisobutyronitrile as an initiator. The resulting homopolymers are highly soluble in supercritical carbon dioxide. Solubility of copolymers is decreased with increase in hydroxyethyl methacrylate content. Simultaneous deposition of copolymers with diisocyanate crosslinking agents from supercritical carbon dioxide solutions allows one to obtain uniform coating of individual fibers of cotton/polyester fabrics. Such coatings show higher water contact angles and delayed transition from Cassie-Baxter to Wenzel state during droplet evaporation than 6,6,7,7,8,8,8-Heptafluoro-5,5-bis(trifluoromethyl)octyl methacrylate or perfluorohexylethyl methacrylate homopolymer coatings.

Electro- and Photophysical Properties of Polymeric Film Composites with Monomers of Pyrido[2,1-b]benzothiazole Derivatives

It was found that film composites of the copolymer of styrene with octyl methacrylate with additions of the monomers of pyrido[2,1-b]benzothiazole derivatives have hole-type photoconductivity while the internal photoelectric effect in this medium is determined by the photogeneration of charge carriers from the monomers and transfer of nonequilibrium charge carriers through these monomers. In transition to a monomer with a more efficient conjugation system the photoconductivity and photovoltaic response are increased.

Automated microfluidic devices integrating solid-phase extraction, fluorescent labeling, and microchip electrophoresis for preterm birth biomarker analysis.

We have developed multichannel integrated microfluidic devices for automated preconcentration, labeling, purification, and separation of preterm birth (PTB) biomarkers. We fabricated multilayer poly(dimethylsiloxane)-cyclic olefin copolymer (PDMS-COC) devices that perform solid-phase extraction (SPE) and microchip electrophoresis (μCE) for automated PTB biomarker analysis. The PDMS control layer had a peristaltic pump and pneumatic valves for flow control, while the PDMS fluidic layer had five input reservoirs connected to microchannels and a μCE system. The COC layers had a reversed-phase octyl methacrylate porous polymer monolith for SPE and fluorescent labeling of PTB biomarkers. We determined μCE conditions for two PTB biomarkers, ferritin (Fer) and corticotropin-releasing factor (CRF). We used these integrated microfluidic devices to preconcentrate and purify off-chip-labeled Fer and CRF in an automated fashion. Finally, we performed a fully automated on-chip analysis of unlabeled PTB biomarkers, involving SPE, labeling, and μCE separation with 1h total analysis time. These integrated systems have strong potential to be combined with upstream immunoaffinity extraction, offering a compact sample-to-answer biomarker analysis platform. Graphical abstract Pressure-actuated integrated microfluidic devices have been developed for automated solid-phase extraction, fluorescent labeling, and microchip electrophoresis of preterm birth biomarkers.

Integrated electrokinetically driven microfluidic devices with pH-mediated solid-phase extraction coupled to microchip electrophoresis for preterm birth biomarkers.

Integration in microfluidics is important for achieving automation. Sample preconcentration integrated with separation in a microfluidic setup can have a substantial impact on rapid analysis of low-abundance disease biomarkers. Here, we have developed a microfluidic device that uses pH-mediated solid-phase extraction (SPE) for the enrichment and elution of preterm birth (PTB) biomarkers. Furthermore, this SPE module was integrated with microchip electrophoresis for combined enrichment and separation of multiple analytes, including a PTB peptide biomarker (P1). A reversed-phase octyl methacrylate monolith was polymerized as the SPE medium in polyethylene glycol diacrylate modified cyclic olefin copolymer microfluidic channels. Eluent for pH-mediated SPE of PTB biomarkers on the monolith was optimized using different pH values and ionic concentrations. Nearly 50-fold enrichment was observed in single channel SPE devices for a low nanomolar solution of P1, with great elution time reproducibility (<7% RSD). The monolith binding capacity was determined to be 400 pg (0.2 pmol). A mixture of a model peptide (FA) and a PTB biomarker (P1) was extracted, eluted, injected, and then separated by microchip electrophoresis in our integrated device with ∼15-fold enrichment. This device shows important progress towards an integrated electrokinetically operated platform for preconcentration and separation of biomarkers.

Синтез и применение сополимеров 4-((2-нитрофенил)диазенил)фенилметакрилата с октилметакрилатом для создания поляризационно-чувствительных голографических сред

Синтез и применение сополимеров 4-((2-нитрофенил)диазенил)фенилметакрилата с октилметакрилатом для создания поляризационно-чувствительных голографических сред

Effect of External Electric Field on Diffraction Efficiency of Polarized Holograms in Films of 4-[(2-Nitrophenyl)Diazenyl]Phenyl Methacrylate Copolymer With Octyl Methacrylate

Holograms with a plane wavefront for parallel and orthogonal orientation of polarization of the light beams were obtained in films of the 4-[(2-nitrophenyl)diazenyl]phenyl methacrylate copolymer with octyl methacrylate, and the effect of an external electric field on their diffraction efficiency was investigated. Two effects from the electric field on the diffraction efficiency of the reconstructed holograms were observed: a fast effect leading to decrease of the diffraction efficiency and a slow effect leading to increase of the diffraction efficiency in the reconstructed holograms. The mechanism of formation of the latent holographic image and the effect of the external electric field on it are due not to the photosemiconducting properties of the films but to optical anisotropy in the isomers of the azobenzene groups and the formation of regular surface relief in the films.

On chip preconcentration and fluorescence labeling of model proteins by use of monolithic columns: device fabrication, optimization, and automation.

Microfluidic systems with monolithic columns have been developed for preconcentration and on-chip labeling of model proteins. Monoliths were prepared in microchannels by photopolymerization, and their properties were optimized by varying the composition and concentration of the monomers to improve flow and extraction. On-chip labeling of proteins was achieved by driving solutions through the monolith by use of voltage then incubating fluorescent dye with protein retained on the monolith. Subsequently, the labeled proteins were eluted, by applying voltages to reservoirs on the microdevice, and then detected, by monitoring laser-induced fluorescence. Monoliths prepared from octyl methacrylate combine the best protein retention with the possibility of separate elution of unattached fluorescent label with 50% acetonitrile. Finally, automated on-chip extraction and fluorescence labeling of a model protein were successfully demonstrated. This method involves facile sample pretreatment, and therefore has potential for production of integrated bioanalysis microchips.

Electrooptical Properties of Polymer Composites with Bisazobenzene Dyes and their Metal Complexes

Polymeric composites based on the copolymer - octyl methacrylate:acrylonitrile (1:1) with incorporated azo dyes: [4-((E)-{4-[(E)-(4-nitrophenyl)diazenyl]phenyl}diazenyl) phenyl]amine, 1-[4-((E)-{4-[(E)-(4-amino phenyl)diazenyl]phenyl}diazenyl)phenyl] ethanone, 4-((E)-{4-[(E)-(4-aminophenyl)diazenyl] phenyl}diazenyl)benzoic acid and its complex with Co were synthesized and their electro-optical properties were investigated. The influence of the electric field on the absorption spectra of new polymer composites with azodyes and complex was investigated. The influence of electronic nature of substitutes in the bisazo chromophores on the electro-optical effect was investigated.

Liquid Crystallinity of Random Copolymers of Polymethacrylates Containing Biphenyl Moieties Synthesized by Atom Transfer Radical Polymerization

4-(4′-Cyanobiphenyloxy)butyl methacrylate, MA(4OCB), was copolymerized with 8-(4′-hexyloxybiphenyloxy)octyl methacrylate, MA(8O6RB), or butyl methacrylate, MA(Bu), by atom transfer radical polymerization. Phase transition behaviors and liquid crystalline properties of the random copolymers with small polydispersity were compared with those of respective homopolymers. The thermal analysis suggested that both biphenyl mesogens in the p[MA(4OCB)-co-(8O6RB)] random copolymers were oriented together rather than segregated. In the case of the p[MA(4OCB)-co-MA(Bu)] random copolymers, the butyl side-chains worked to diminish liquid crystallinity by disturbing orientation of the biphenyl mesogen due to thermal fluctuation.

Synthesis, Characterization, and Properties of Thermotropic Novel Liquid Crystal Photosensitive Polymers Containing Mesogen and Photocrosslinkable Group

A series of side chain liquid crystalline photosensitive polymers containing methyl methacrylate followed by the spacer and chalcone moiety were synthesized and characterized. Monomers, namely 4-[4{biphenyl oxy carbonyl phenyl oxy carbonyl} phenyl carbonyl ethylene phenyl] oxy butyl methacrylate (BOCPOCPCEPOBMA) and 4-[4{1-methoxy phenyl oxy carbonyl phenyl oxy carbonyl} phenyl carbonyl ethylene phenyl] oxy octyl methacrylate (MPOCPOCPCEPOOMA) was synthesized and subsequently polymerized using benzoyl peroxide as an initiator. The chemical structures and purity were characterized by FT-IR, 1H- NMR, and 13C-NMR analyses. The photocrosslinking studies of the polymers were investigated by UV spectroscopy. The rate of crosslinking increased with increase in the length of the methylene chain. The results of differential scanning calorimeter (DSC) analysis confirmed the formation of mesophase in the polymers. Hot stage optical polarized microscopy (HOPM) showed presence of nematic phase for poly (BOCPOCPCEPOBMA) and poly (MPOCPOCPCEPOOMA).

Electro-optical properties of film polymer composites with bis-azo dyes and bis-azo metal complexes

New bis-azo dyes and complexes of these with cobalt are synthesized and used in photo-active film polymer composites based on an octyl methacrylate:acrylonitrate (1:1) copolymer. After creation of an optical anisotropy in these films, the kinematics and spectral characteristics of the electro-optical effect are studied. A huge change (greater than 80 %) is detected in the intensity of the light passing through a polarizer, the film, and an analyzer. The giant electro-optical effect and its rather fast kinetics are explained by the elasticity of the polymer matrix, which contains polar groups, and by the compatibility of the new azo-compounds with the matrix.

A New Acrylamide-Based Peroxide Monomer: Synthesis and Copolymerization with Octyl Methacrylate

N-[(tert-Butylperoxy)methyl]acrylamide (tBPMAAm), a new peroxide monomer containing a primary-tertiary peroxide group, was synthesized and employed for radical copolymerization with octyl methacrylate (OMA) to yield a novel functional polyperoxide (FPP). Copolymerization kinetics were analyzed to find tBPMAAm and OMA monomer reactivity ratios (r1, r2) and Q − e values. Kinetic characteristics provide a way to control FPP composition and its reactivity in radical processes. It is expected that the developed functional polyperoxide containing long alkyl fragments provides an affinity to polymeric surface. At the same time, since the peroxide groups readily decompose at elevated temperatures, the FPP can be used as a macroinitiator of radical polymerization. As a result, we expect that in the future the FPP will be applied as an efficient modifier of the polymeric surface.

Preparation of stir bars for sorptive extraction based on monolithic material

A stir bar for sorption extraction based on monolithic material (SBSEM) was prepared in this study. The monolithic material was obtained by in situ copolymerization of octyl methacrylate and ethylene dimethacrylate in the presence of a porogen solvent containing 1-propanol, 1,4-butanediol, and water with azobisisobutyronitrile as the initiator. The influences of polymerization parameters and the thickness of monolithic materials on the adsorption and desorption efficiencies were investigated, using naphthalene, phenanthrene and fluoranthene as detected solutes. The results show that monolithic material possessed good permeability resulting in fast adsorption and desorption for detected solutes. Spiked seawater samples containing eight polycyclic aromatic hydrocarbons (PAHs) and urine samples containing four anabolic steroids were preliminarily analyzed by using the sorptive bars and liquid desorption followed by high performance liquid chromatography with diode array detection. The results demonstrate that prepared stir bar was suitable for preconcentration of both apolar and polar analytes. The enrichment factors for phenanthrene, anthracene and pyrene were 150, 134 and 189, respectively. The SBSEM shows good batch-to-batch reproducibility and good stability, and can be reused a least 10 times for the extraction of polycyclic aromatic hydrocarbons in seawater.

Phase behavior on the poly[octyl (meth)acrylate] + supercritical fluid solvents + monomer and CO 2 + monomer mixtures at high pressure

Experimental cloud-point data to 220 °C and 2660 bar are reported for binary and ternary mixtures of poly(octyl acrylate) [P(OA)] + CO 2 + octyl acrylate (OA), poly(octyl methacrylate) [P(OMA)] + CO 2 + octyl methacrylate (OMA), and P(OA) + supercritical solvents systems. The cloud-point curves for the P(OA) + CO 2 + OA (or dimethyl ether (DME)) system changes the pressure–temperature ( P– T) curve from upper critical solution temperature (UCST) region to lower critical solution temperature (LCST) region as the OA (or DME) concentration increases. The P(OA) + C 4 hydrocarbons cloud-point curves are ∼150 bar lower than the P(OA) + C 3 hydrocarbons curves at fixed temperature. The phase behavior for the system P(OMA) + CO 2 + OMA are measured in changes of the P– T slope, and with cosolvent concentrations of 0–42.4 wt.%. High pressures phase behavior data are measured for the CO 2 + OA and CO 2 + OMA systems at the temperature range from 40 to 120 °C and pressures up to ∼208 bar. Both system exhibit type-I phase behavior with a continuous mixture-critical curve and both are adequately modeled with the Peng–Robinson equation of state.

Photosensitivity of holographic recording media based on films of polymer compositions with cadmium sulfide nanoparticles

The effect of doping with CdS nanoparticles of recording medium films for the thermoplastic holographic recording process, which are based on photosemiconductors (oligomers and cooligomers of glycidylcarbazole) and a dielectric (a styrene copolymer with octyl methacrylate) containing a photoconductivity sensitizer, on their photosensitivity was studied. The enhancement of photosensitivity of films by doping with nanoparticles is associated with the appearance of an additional channel for transport of electrons generated from sensitizer molecules. A difference in informational properties between the oligomer and the polymer films was revealed.

Reversible oxygen-binding and facilitated oxygen transport in membranes of polyvinylimidazole complexed with cobalt-phthalocyanine

A membrane with an oxygen-binding capability and nanometer thickness was prepared by complexing cobalt-phthalocyanine as an oxygen carrier with the copolymer of vinylimidazole and octyl methacrylate. The complex showed reversible oxygen-binding in the solution state at low temperature. The permeability coefficient of oxygen ( P O 2 ) through this membrane was much higher than that of nitrogen ( P N 2 ) ( P O 2 / P N 2 > 20 ) and increased at lower upstream oxygen pressure. The facilitation of oxygen transport was augmented by increasing the concentration of the oxygen carrier, cobalt-phthalocyanine fixed in the membrane.

Photophysical processes and photochemical reactions involved in poly( N-vinylcarbazole) and in copolymers with carbazole units

This paper is devoted to the analysis of the photochemical behaviour of copolymers with carbazole units exposed to long-wavelength radiation. These copolymers are constituted of two types of carbazolylethyl methacrylate units (CEM) with octyl methacrylate moieties (OMA). The exposure of copolymers and PVK to UV light results in dramatic modifications of the physical and photophysical properties of the polymer. These modifications can be correlated with modifications of the chemical structure of the matrix. The photoageing of copolymers and PVK has been analysed by fluorescence, ESR, UV–vis and infrared spectroscopies. The effects of crosslinking and chain scissions were determined by gel fraction measurements and size exclusion chromatography.

Octyl-type monolithic columns of 530μm i.d. for capillary liquid chromatography

A novel monolithic capillary column (530 microm i.d.) was prepared for capillary liquid chromatography (CLC) by in situ copolymerization of octyl methacrylate (MAOE) and ethylene dimethacrylate (EDMA) in the presence of a porogen solvent containing 1-propanol, 1,4-butanediol, and water with azobisisobutyronitrile as the initiator. The influences of the contents of the porogen solvent, EDMA and the various concentration ratios of 1-propanol to 1,4-butanediol in the polymerization mixture on the morphology, porosity, globule size, stability and column efficiency were investigated. The morphology and pore size distribution of monolithic capillary columns were characterized by SEM and mercury intrusion porosimetry, respectively. Chromatographic evaluations of the columns were performed under CLC mode. The results showed that good permeability and stability can be obtained under optimal experimental conditions. The separation results of some acid, neutral and basic analytes demonstrated the hydrophobicity and low affinity to basic analytes of the new column. Three metal ions, i.e. Mg(II), Zn(II) and Cd(II) were also separated under ion-pair mode on the new monolithic capillary column and the results were acceptable.

Synthesis and characterization of acrylic terpolymers with RGD peptides for biomedical applications

The goal of this research was to design a biomaterial, using acrylic terpolymers, which could support endothelial cells and function in small diameter vascular graft applications. Hexyl methacrylate (HMA) and octyl methacrylate (OMA) were used as comonomers to produce a material with a low glass transition temperature ( T g). Methacrylic acid (MAA) was used to provide ionic character, and methyl methacrylate (MMA) was selected because of its wide usage in biomedical applications. Cation neutralization was employed to modify the mechanical properties. RGD-based peptide sequences were attached to promote endothelial cell adhesion, because vascular grafts seeded with endothelial cells have fewer problems with thrombosis. The two methods used to incorporate peptide sequences were a chain transfer reaction during polymerization, and a coupling reaction attaching the peptides to carboxyl groups on the polymer after polymerization. The compositions that produced T gs of approximately 0°C were 75 mol% OMA and 92 mol% HMA. The Young's modulus of the HMA copolymer was approximately 0.37 MPa, well below the desired value of 0.9 MPa. Likewise, the Young's modulus of approximately 0.50 MPa for the OMA copolymer was also below the desired value. After partial neutralization with sodium cations, the Young's moduli increased to approximately 0.93 and 0.99 MPa, respectively. The chain transfer reaction lowered the molecular weights and mechanical properties of the copolymers, while the coupling reaction method had little effect on these properties. The chain transfer method appears to be a promising one-step method to produce polymers with a wide range of peptide concentrations.

Kinetic modeling of the effect of solvent concentration on primary cyclization during polymerization of multifunctional monomers

Controlling the swelling ratio, diffusion rate, and mechanical properties of a crosslinked polymer is important in hydrogel design for biomedical applications. Each of these factors depends strongly on the degree of crosslinking. Primary cyclization, where a propagating radical reacts intramolecularly with a pendant double bond on the same chain, decreases the crosslinking density and increases the molecular weight between crosslinks. Processing conditions, specifically the solvent concentration, strongly affect the extent of primary cyclization. In this work the effects of solvent concentration and comonomer composition on primary cyclization are investigated using a novel kinetic model and experimental measurement of mechanical properties. Two divinyl crosslinking agents were investigated, diethyleneglycol dimethacrylate (DEGDMA) and polyethyleneglycol 600 dimethacrylate (PEG(600)DMA), and each was copolymerized with hydroxyethyl methacrylate (HEMA) and octyl methacrylate (OcMA). The model is further used to predict the gel point conversion and swelling ratio of PAA hydrogels polymerized in the presence of varying amounts of water. Model results show how increasing the solvent concentration during the polymerization increases the molecular weight between crosslinks by nearly a factor of three and more than doubles the swelling ratio. Where possible, experimental results provide quantitative agreement with model predictions.