Methyl Ethyl Ketone Solution Research Articles

Effects of Annealing on the Optical and Electronic Properties of Poly (vinylidene fluoride-trifluoroethylene) Copolymer Thin Films

Thin films of vinylidene fluoride with trifluoroethylene [P(VDF-TrFE)] copolymer have been deposited onto bare Si and SiO2 by spin casting from methylethylketone solutions. The structures and optical and electronic properties for P(VDF-TrFE) films after vacuum and forming gas annealing were studied. The degree of structural order and the crystallinity determined by X-ray diffraction were increased with the thermal annealing time. Ellipsometry spectroscopy were employed to investigate the changes in the thickness, refractive indices n, and the anisotropic properties. The results reflected that the n was increased with the thermal annealing time and temperature, and the anisotropy of the annealed films was strengthened with the annealing time and temperature. Metal-polymer-(oxide)-semiconductor capacitors were used to measure the static dielectric constant K and interfacial electronic properties of P(VDF-TrFE) on Si which the K increase with film thickness and thermal annealing. The interface at Al-P(VDF-TrFE) and/or P(VDF-TrFE)-Si affect the K value which is sensitive for films thinner than 120 nm. The Si-P(VDF-TrFE) interface quality determined using capacitance-voltage and current-voltage measurementswas found to be improved after forming gas annealed.

Mass Diffusion Coefficients of Cellulose Acetate Butyrate in Methyl Ethyl Ketone Solutions at Temperatures between (293 and 323) K and Mass Fractions from 0.05 to 0.60 Using the Soret Forced Rayleigh Scattering Method

The binary mass diffusion coefficients of cellulose acetate butyrate in methyl ethyl ketone solutions (CAB + MEK) have been measured under atmospheric pressure at temperatures from (293 to 323) K and mass fractions from 0.05 to 0.6. The present experimental apparatus is based on the Soret forced Rayleigh scattering method (S-FRSM), which utilizes the Soret effect to create periodic spatial concentration modulation of micrometer-order fringe spacing in a sample binary liquid mixture due to the absorption of an optical interference grating generated by two intersecting heating laser beams. The decay of the concentration modulation by the mass diffusion process is monitored by the diffraction of a probing laser beam. This method provides several advantages in comparison with conventional techniques such as Taylor dispersion or diaphragm cells; namely, a single measurement can be performed within a short time [(10−3 to 10−2) s], with small temperature and concentration changes (ΔT < 10−2 K and Δc < 10−5) usin...

Micellization in solutions of hybrid block copolymer of poly(methyl methacrylate) and hyperbranched perfluorinated poly(phenylene germane)

Fractions of the product resulting from the polymerization of methyl methacrylate in the presence of hyperbranched perfluorinated poly(phenylene germane) have been studied by dynamic and static light scattering and capillary viscometry in methyl ethyl ketone solutions. The hybrid product is obtained via the reaction of the chain transfer of methyl methacrylate propagating radicals to pentafluorophenyl groups. Eight fractions have been isolated by fractional precipitation, including fractions of the linear-dendrite block copolymer. Light scattering studies have shown that hybrid macromolecules containing 15–20 wt % hyper-branched fragments form micelles in solutions.

Synthesis, characterization and thermal properties of homo and copolymers of 3,5-dimethoxyphenyl methacrylate with glycidyl methacrylate: Determination of monomer reactivity ratios

The new methacrylic monomer, 3,5-dimethoxyphenyl methacrylate (DMOPM) was synthesized by reacting 3,5-dimethoxyphenol dissolved in ethyl methyl ketone (EMK) with methacryloyl chloride in presence of triethylamine as a catalyst. The homopolymer and copolymers of DMOPM with glycidyl methacrylate (GMA) were synthesized by free radical polymerization in EMK solution at 70 ± 1 °C using benzoyl peroxide as a free radical initiator. The copolymerization behaviour was studied in a wide composition interval with the mole fractions of DMOPM ranging from 0.15 to 0.9 in the feed. The homopolymer and the copolymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The solubility was tested in various polar and non-polar solvents. The molecular weight and polydispersity indices of the polymers were determined using gel permeation chromatography. The glass transition temperature of the copolymers increases with increase in DMOPM content. The thermogravimetric analysis of the polymers showed that the thermal stability of the copolymer increases with DMOPM content. The copolymer composition was determined using 1H NMR spectra. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman–Ross ( r 1 = 0.520, r 2 = 2.521), Kelen–Tudos ( r 1 = 0.629, r 2 = 2.554) and extended Kelen–Tudos methods ( r 1 = 0.600, r 2 = 2.502).

Dispersion-Flocculation Behavior of Fine Lead Particles in an Organic Solvent

Methyl ethyl ketone (MEK) is a good solvent for polyvinyl chloride (PVC) and it has been proposed for use in PVC recycling. In the recycling process, fine particles of 3PbO·PbSO 4 ·H 2 O, used as a thermal stabilizer in PVC products, are dispersed and not dissolved in the solvent. To establish methods for removing of 3PbO·PbSO 4 ·H 2 O particles from the solvent, factors affecting the dispersion-flocculation behavior of the particles in MEK were investigated. The zeta potential and particle distribution of 3PbO·PbSO 4 ·H 2 O particles in MEK solutions containing known amounts of H 2 O were measured. Above 5 vol%H 2 O in MEK solutions, the zeta potential of 3PbO·PbSO 4 ·H 2 O particles approached zero and the flocculation of particles was achieved. In addition, it was found that Pb 2+ and Cl - affect the zeta potential of the particles. These results indicate that the dispersion-flocculation behavior of lead particles can be influenced by the concentration of H 2 O, Pb 2+ , and Cl - in MEK.

Kinetics of the adsorption of polystyrene macromolecules from dilute solutions in methyl ethyl ketone on carbon black

The kinetics of the adsorption of a mixture of three polystyrenes (the weight-average molecular weight M w = 8300, 34000, and 195000) on nonporous carbon (carbon black pretreated in the argon flow at 3800 K) from dilute solutions in methyl ethyl ketone at 298 K is studied. The kinetic dependences of the adsorption of polystyrenes on carbon black nanoparticles from solutions in methyl ethyl ketone are described by adsorption kinetics equations previously used for describing the adsorption of aromatic hydrocarbons from aqueous solutions by active carbon. The correlation between the kinetic coefficients and the molecular weights of polystyrenes is discussed.

Homopolymer and copolymers of 4-nitro-3-methylphenyl methacrylate with glycidyl methacrylate: Synthesis, characterization, monomer reactivity ratios and thermal properties

The novel methacrylic monomer, 4-nitro-3-methylphenyl methacrylate (NMPM) was synthesized by reacting 4-nitro-3-methylphenol dissolved in ethyl methyl ketone (EMK) with methacryloyl chloride in the presence of triethylamine as a catalyst. The homopolymer and copolymers of NMPM with glycidyl methacrylate having different compositions were synthesized by free radical polymerization in EMK solution at 70 ± 1 °C using benzoyl peroxide as free radical initiator. The homopolymer and the copolymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The solubility tests were tested in various polar and non-polar solvents. The molecular weight and polydispersity indices of the copolymers were determined using gel permeation chromatography. The glass transition temperature of the copolymers increases with increase in NMPM content. The thermogravimetric analysis of the polymers performed in air showed that the thermal stability of the copolymer increases with NMPM content. The copolymer composition was determined using 1H NMR spectra. The monomer reactivity ratios were determined by the application of conventional linearization methods such Fineman–Ross ( r 1 = 1.862, r 2 = 0.881), Kelen–Tudos ( r 1 = 1.712, r 2 = 0.893) and extended Kelen–Tudos methods ( r 1 = 1.889, r 2 = 0.884).

Copolymerization of 4-biphenyl methacrylate with glycidyl methacrylate: Synthesis, Characterization, thermal properties and determination of monomer reactivity ratios

The methacrylic monomer, 4-biphenylmethacrylate (BPM) was synthesized by reacting 4-biphenyl phenol dissolved in ethyl methyl ketone (EMK) with methacryloyl chloride in presence of triethylamine as a catalyst. The copolymers of BPM with glycidyl methacrylate (GMA) were synthesized by free radical polymerization in EMK solution at 70±1 °C using benzoyl peroxide as a free radical initiator. The copolymerization behaviour was studied in a wide composition interval with the mole fractions of BPM ranging from 0.15 to 0.9 in the feed. The copolymers were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. The solubility was tested in various polar and non polar solvents. The molecular weight and polydispersity indices of the polymers were determined using gel permeation chromatography. The glass transition temperature of the copolymers increases with increase in BPM content. The thermogravimetric analysis of the polymers showed that the thermal stability of the copolymer increases with BPM content. The copolymer composition was determined using 1H-NMR spectra. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman-Ross (r1=0.392 ± 0.006, r2 = 0.358 ± 0.007, Kelen-Tudos (r1= 0.398 ± 0.004, r2= 0.365 ± 0.013) and extended Kelen-Tudos methods (r1= 0.394 ± 0.004, r2= 0.352 ± 0.006).

Reflectionless absorption of superhigh-frequency radiation in solutions of methyl ethyl ketone and methyl isobutyl ketone in n-heptane

Investigations of dielectric properties of solutions of methyl ethyl ketone and methyl isobutyl ketone in n-heptane in a microwave range established the existence, in these solutions, of a spectrum of concentrations and thicknesses of the solution layer at which resonant reflectionless radiation absorption originates.

Polymer–nanoparticle interfacial interactions in polymer nanocomposites: Confinement effects on glass transition temperature and suppression of physical aging

AbstractThe effects of confinement on glass transition temperature (Tg) and physical aging are measured in polystyrene (PS), poly(methyl methacrylate) (PMMA), and poly(2‐vinyl pyridine) (P2VP) nanocomposites containing 10‐ to 15‐nm‐diameter silica nanospheres or 47‐nm‐diameter alumina nanospheres. Nanocomposites are made by spin coating films from sonicated solutions of polymer, nanofiller, and dye. The Tgs and physical aging rates are measured by fluorescence of trace levels of dye in the films. At 0.1–10 vol % nanofiller, Tg values can be enhanced or depressed relative to neat, bulk Tg (Tg,bulk) or invariant with nanofiller content. For alumina nanocomposites, Tg increases relative to Tg,bulk by as much as 16 K in P2VP, decreases by as much as 5 K in PMMA, and is invariant in PS. By analogy with thin polymer films, these results are explained by wetted P2VP–nanofiller interfaces with attractive interactions, nonwetted PMMA–nanofiller interfaces (free space at the interface), and wetted PS–nanofiller interfaces lacking attractive interactions, respectively. The presence of wetted or nonwetted interfaces is controlled by choice of solvent. For example, 0.1–0.6 vol % silica/PMMA nanocomposites exhibit Tg enhancements as large as 5 K or Tg reductions as large as 17 K relative to Tg,bulk when films are made from methyl ethyl ketone or acetic acid solutions, respectively. A factor of 17 reduction of physical aging rate relative to that of neat, bulk P2VP is demonstrated in a 4 vol % alumina/P2VP nanocomposite. This suggests that a strategy for achieving nonequilibrium, glassy polymeric systems that are stable or nearly stable to physical aging is to incorporate well‐dispersed nanoparticles possessing attractive interfacial interactions with the polymer. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 2935–2943, 2006

Studies on copolymers of 3-methacryloyloxystyryl-4′-methylphenyl ketone and methyl methacrylate

Copolymers with various contents of 3-methacryloyloxystyryl-4′-methylphenyl ketone (MSMPK) and methyl methacrylate (MMA) were prepared in methyl ethyl ketone solution using benzoyl peroxide as a free radical initiator at 70 °C. Characterization of the resulting polymers was done by UV, FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The copolymer compositions were determined by 1H NMR analysis. The monomer reactivity ratios were calculated using linearization methods such as Finemann–Ross ( r 1 = 0.9439 and r 2 = 0.3656), Kelen–Tüdös ( r 1 = 0.9726 and r 2 = 0.4172), and extended Kelen–Tüdös ( r 1 = 0.9731 and r 2 = 0.4055) methods as well as by a non-linear error-in-variables model (EVM) method using the computer program RREVM ( r 1 = 0.9043 and r 2 = 0.3901). The molecular weights ( M ¯ w and M ¯ n ) and the polydispersity index of the copolymers were determined by gel permeation chromatography. The thermal stability of the copolymers solution increases with increase in concentration of MSMPK. Glass transition temperatures were determined by differential scanning calorimeter under nitrogen atmosphere. The photoreactivity of the copolymers having pendant chalcone moieties was studied in chloroform.

A study of the optical and electronic properties of poly (vinylidene fluoride–trifluoroethylene) copolymer thin films

Thin films of poly(vinylidene fluoride–trifluoroethylene) copolymer were prepared by spin casting from methylethylketone solutions onto SiO 2, Si, and quartz slides substrates. The films were optically transparent in the 1.5–4.5 eV (830–280 nm) photon energy range and found to be uniform and smooth as determined using near ultraviolet–visible spectrum and atomic force microscopy, respectively. A Cauchy model was used to fit spectroscopic ellipsometry (SE) data to obtain the refractive index in 1.5–4.5 eV (830–280 nm) that was found to decrease for thinner films. SE performed at several sensitive angles of incidence has revealed slight optical anisotropy for films thicker than 120 nm. Annealing in vacuum densified the films as evidenced by an increase in the refractive index and a decrease in the film thickness. Capacitance versus voltage measurements revealed a static dielectric constant of about 7.5.

Homopolymer and copolymers of 4‐methacrylamidophenyl‐4‐methoxystyryl ketone with methyl methacrylate: Synthesis, characterization, reactivity ratios, and photocrosslinkable properties

Abstract4‐Aminophenyl‐4‐methoxystyryl ketone (APMSK) was prepared by reacting 4‐aminoacetophenone and 4‐methoxybenzaldehyde in the presence of sodium hydroxide as base catalyst. The methacrylamide monomer, 4‐methacrylamidophenyl‐4‐methoxystyryl ketone (MPMSK), was synthesized by reacting APMSK with methacryloyl chloride in the presence of triethylamine. Free‐radical solution polymerization technique was used to prepare the homo‐ and copolymers of different feed compositions of MPMSK with methyl methacrylate in methyl ethyl ketone solution at 70°C, using benzoyl peroxide as the initiator. The polymers were characterized by UV, IR, 1H‐NMR, and 13C‐NMR spectral techniques. The reactivity ratios of both comonomers were calculated using Fineman–Ross, Kelen–Tüdös, extended Kelen–Tüdös, and a nonlinear error‐in‐variables model (EVM) method using a computer program, RREVM. The molecular weights (M̄w and M̄n) and polydispersity indices of the polymers were determined using size exclusion chromatography. The glass‐transition temperatures of the polymers were determined by differential scanning calorimetry. The thermal stability of the polymers was measured by thermogravimetric analysis in air. The photoreactivity of the polymers was studied in chloroform solutions in the presence and absence of various triplet sensitizers. The effect of concentration of homopolymer and composition of the copolymers on the rate of photocrosslinking of the polymers was investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci, 2006

Poly[bis(2,2,2-trifluoroethoxy)phosphazene] Superhydrophobic Nanofibers

Nanofibers of poly[bis(2,2,2-trifluoroethoxy)phosphazene] were produced by electrospinning from solutions in tetrahydrofuran, methylethyl ketone, and acetone. The fiber diameter varied from 80 nm to 1.4 microm by changes in the concentration of the polymer solution. The electrospun nonwoven mats showed enhanced surface hydrophobicity compared to spun cast films with up to a 55 degrees increase in water contact angle. The hydrophobicity varied with fiber diameter and surface morphology, with contact angles to water being in the range of 135 degrees -159 degrees. A low value of hysteresis (<4 degrees) was recorded for the superhydrophobic surfaces. The extremely high hydrophobicity of these mats is a combined result of a fluorinated surface and the inherent surface roughness of an electrospun mat.

Copolymerization of Benzoylphenyl Methacrylate with Methyl Methacrylate: Synthesis, Characterization and Determination of Monomer Reactivity Ratios

4‐Benzoylphenyl methacrylate (BPM) was prepared by reacting 4‐hydroxy benzophenone dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine. The copolymers of BPM with methyl methacrylate (MMA) having different copolymer composition were synthesized in a MEK solution using benzoyl peroxide (BPO) as a free radical initiator at 70±1°C. The copolymers were characterized by FT‐IR, 1H‐NMR and 13C‐NMR spectroscopic techniques. The molecular weights (M¯w and M¯n) and polydispersity indices (M¯w/M¯n) of the polymers were determined using gel permeation chromatograph. The glass transition temperatures (Tg) of the copolymers determined by differential scanning calorimeter reveals that Tg increases with increase in BPM content in the copolymer. Thermogravimetric analysis of the polymers performed in air shows that the stability of the copolymer increases with an increase in BPM content. The solubility of the polymers was tested in various polar and non‐polar solvents. Copolymer compositions were determined by the 1H‐NMR spectroscopy by comparing the integral peak areas of well separated aromatic and aliphatic proton peaks. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman‐Ross (r1=2.201: r2=0.814), Kelen Tüdös (r1=2.121: r2=0.634), extended Kelen Tüdös (r1=2.153: r2=0.698), as well as by a non‐linear error‐in‐variable model method (EVM) using a computer program RREVM (r1=1.638: r2=0.543).

Studies on photocrosslinkable copolymers of 4-methacryloyloxyphenyl-3′,4′-dimethoxystyryl ketone and methyl methacrylate

Copolymers with various contents of 4-methacryloyloxyphenyl-3′,4′-dimethoxystyryl ketone (MPDSK) and methyl methacrylate (MMA) were prepared in methyl ethyl ketone solution using benzoyl peroxide as a free radical initiator at 70 °C. Characterization of the resulting polymers was done by UV, FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The copolymer compositions were determined by 1H NMR analysis. The monomer reactivity ratios were calculated using linearisation methods such as Finemann–Ross ( r 1 = 0.4283 and r 2 = 0.3050), Kelen–Tudos ( r 1 = 0.4264 and r 2 = 0.2606), and extended Kelen–Tudos ( r 1 = 0.4022 and r 2 = 0.2704) methods as well as by a non-linear error-in-variables model (EVM) method using the computer program RREVM ( r 1 = 0.4066 and r 2 = 0.2802). The molecular weights ( M ¯ w and M ¯ n ) and the polydispersity index of the copolymers were determined by gel permeation chromatography. The thermal stability of the copolymers increases with increase in concentration of MPDSK. Glass transition temperatures were determined by differential scanning calorimeter under nitrogen atmosphere. The photoreactivity of the copolymers having pendant chalcone moieties was studied in chloroform solution.

Chemiluminescence in the course of methyl ethyl ketone oxidation by ozone in acidic aqueous solutions

Chemiluminescence in the visible spectral region is observed in the course methyl ethyl ketone oxidation by ozone in neutral and acidic aqueous solutions. The spectral composition of the chemiluminescence is studied. On going from neutral to acidic aqueous solutions of methyl ethyl ketone, the initial intensity of the signal increases and the kinetics of a decrease in the chemiluminescence intensity changes. A radical scheme of the process is proposed to explain the results obtained.

Homopolymer of 4-benzoylphenyl methacrylate and its copolymers with glycidyl methacrylate: synthesis, characterization, monomer reactivity ratios and application as adhesives

The methacrylic monomer, 4-benzoylphenyl methacrylate (BPM) was synthesized by reacting 4-hydroxy benzophenone dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine. The homopolymer and various copolymers of BPM with glycidyl methacrylate were synthesized by free radical polymerization in MEK solution at 70 ± 1 °C using benzoyl peroxide as initiator. The homopolymer and the copolymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The molecular weight ( M w ¯ and M n ¯ ) and polydispersity indices of the copolymers determined using gel permeation chromatograph suggest that the chain termination by radical recombination was predominant when the mole fraction of GMA was high in the feed. The glass transition temperature of the copolymer increases with increase in BPM content. The thermal stability of the copolymers increases with increases in BPM content. The copolymer composition was determined using 1H NMR spectra. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman–Ross ( r 1 = 1.490; r 2 = 0.824), Kelen–Tudos ( r 1 = 1.411; r 2 = 0.712), Extended Kelen–Tudos ( r 1 = 1.437; r 2 = 0.707) as well as by a non-linear error in variables model (EVM) method using a computer program, RREVM ( r 1 = 1.364; r 2 = 0.69). The copolymer having 56%, 41% and 28% of GMA content were chosen for making adhesives by curing with diethanolamine in choloroform. The cured resins were tested for the adhesion properties on leather–leather bonding at 50 and 90 °C. It was found that the resin cured at 50 °C exhibited maximum peel strength of 0.73, 0.58 and 0.30 N/mm, respectively, revealing a good adhesive behaviour.

Segmental and secondary dynamics in hydrogen‐bonded poly(4‐vinylphenol)/poly(methyl methacrylate) blends

AbstractBroadband dielectric spectroscopy was used to study the segmental (α) and secondary (β) relaxations in hydrogen‐bonded poly(4‐vinylphenol)/poly(methyl methacrylate) (PVPh/PMMA) blends with PVPh concentrations of 20–80% and at temperatures from −30 to approximately glass‐transition temperature (Tg) + 80 °C. Miscible blends were obtained by solution casting from methyl ethyl ketone solution, as confirmed by single differential scanning calorimetry Tg and single segmental relaxation process for each blend. The β relaxation of PMMA maintains similar characteristics in blends with PVPh, compared with neat PMMA. Its relaxation time and activation energy are nearly the same in all blends. Furthermore, the dielectric relaxation strength of PMMA β process in the blends is proportional to the concentration of PMMA, suggesting that blending and intermolecular hydrogen bonding do not modify the local intramolecular motion. The α process, however, represents the segmental motions of both components and becomes slower with increasing PVPh concentration because of the higher Tg. This leads to well‐defined α and β relaxations in the blends above the corresponding Tg, which cannot be reliably resolved in neat PMMA without ambiguous curve deconvolution. The PMMA β process still follows an Arrhenius temperature dependence above Tg, but with an activation energy larger than that observed below Tg because of increased relaxation amplitude. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3405–3415, 2004

Homopolymer of 4-propanoylphenyl methacrylate and its copolymers with glycidyl methacrylate: synthesis, characterization, reactivity ratios and application as adhesives

The methacrylic monomer, 4-propanoylphenyl methacrylate (PPM) was synthesized by reacting 4-hydroxyl propiophenone dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine. The homopolymer and various compositions of copolymers with glycidyl methacrylate (GMA) were synthesized using free radical polymerization in MEK solution at 70 ± 1 °C using benzoyl peroxide as initiator. The polymers were characterized by FT-IR, 1H NMR and 13C NMR techniques. The polydispersity indices of the copolymers determined using gel permeation chromatograph suggest that the chain termination by disproportionation predominates coupling when the mole fraction of GMA in the feed is high and radical recombination was predominant when the mole fraction of PPM was high in the feed. The glass transition temperature of the copolymer increases with increase in PPM content. The thermal stability of the copolymers increases with increase in PPM content. The copolymer compositions were determined using 1H NMR analysis. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman–Ross ( r 1=1.441: r 2=0.747), Kelen–Tüdös ( r 1=1.497: r 2=0.713), extended Kelen–Tüdös ( r 1=1.441: r 2=0.708) and a non-linear error-in-variables model (EVM) method using a computer program, RREVM ( r 1=1.264: r 2=0.653). These values suggest that PPM is more reactive than GMA and the copolymer will be richer in PPM units. The adhesives based on poly(PPM- co-GMA) were prepared for the application on leather and their peel strength were determined at 50 and 70 °C.