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Electrocatalytic Properties Of Platinum Doped Polyaniline And Polypyrrole Electrodes, F. Kadirgan, F. Fiçicioğlu, İ. Beceri̇k Jan 1998

Electrocatalytic Properties Of Platinum Doped Polyaniline And Polypyrrole Electrodes, F. Kadirgan, F. Fiçicioğlu, İ. Beceri̇k

Turkish Journal of Chemistry

This review paper aims to show how the electrochemical behaviour of polyaniline (PANI) and polypyrrole (PPy) electrodes modified by platinum help to improve the oxidation of organic molecules such as methanol, ethylene glycol and glucose. Although the amount of platinum deposited was very small, i.e., 0.1 mg.cm$^{-2}$, the catalytic activity obtained was comparable to bulk platinum. Another notable point is the reduction of the poisoning effect, which is the main problem faced in the electrooxidation of organic molecules for fuel cell applications.


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Heat Treatment Of Maceral Groups Obtained From Turkish Bituminous Coals, Elif Sultan Vayi̇soğlu, Nevin Gaye Erbatur Jan 1998

Heat Treatment Of Maceral Groups Obtained From Turkish Bituminous Coals, Elif Sultan Vayi̇soğlu, Nevin Gaye Erbatur

Turkish Journal of Chemistry

The dilatation properties of parent coals and their maceral fractions were examined. In all the coal samples, the main petrographic constituent was the vitrinite maceral. Reflectance of the vitrinite and inertinite macerals increased after carbonization, while the liptinite maceral disappeared and caused large pores in the vitrinite macerals. All of the coals developed anisotropic coke.


Heme Transfer Reactions: An Important Prerequisite For Synthetic Oxygen Carriers, Jan Paul, Wenhua Chen, Per-Ingvar Ohlsson, Michael Smith Jan 1998

Heme Transfer Reactions: An Important Prerequisite For Synthetic Oxygen Carriers, Jan Paul, Wenhua Chen, Per-Ingvar Ohlsson, Michael Smith

Turkish Journal of Chemistry

Electronic changes of iron- and metal free porphyrins are reviewed in light of their importance to modify the ferri/ferro reduction potential and energy dissipation between ligated carbon monoxide and the porphyrin chelate. Substitutions at positions 2 and 4 are effective ways to exercise this influence. Other measures include exposure to water and modifications of axial ligation, including the \lq three-ligand' case. These measures will also influence the stability of recombined hemin-protein entities, as apparent from the kinetics of heme-transfer from a modified donor protein to apomyoglobin, but the stability appears to be related to the bulkiness of 2,4-substitutional groups rather …


Some Recursive Relationships Between Acenes And Cyclacenes, Lemi Türker Jan 1998

Some Recursive Relationships Between Acenes And Cyclacenes, Lemi Türker

Turkish Journal of Chemistry

Some structural relationships between acenes and cyclacenes both H\\"{u}ckel- and Mobius-type and within the same class of compounds were demonstrated by the recursive analysis of their $E_{\pi}$ and $I_{\pi}$ values or the first differences thereof. It was found that the first differences of $E_{\pi}$ and $I_{\pi}$ tend to have certain limit values as the number of benzenoid rings increases in each class of compounds studied.


The Amido And Bisalkoxo-Complexes Of [Tri(3,5-Dimethylpyrazolyl)Borato]Molydenum Nitrosyl, Işıl Topaloğlu Jan 1998

The Amido And Bisalkoxo-Complexes Of [Tri(3,5-Dimethylpyrazolyl)Borato]Molydenum Nitrosyl, Işıl Topaloğlu

Turkish Journal of Chemistry

In this study, the amido nitrosyl molybdenum complex, [Mo{HM(3,5-Me_2C_3HN_2)_3}(NO)Cl(NH_2)], was prepared. This compound reacts with alocohols, yielding the bisalkoxo complexes, [Mo{HM (3,5-Me_2C_3HN_2)_3}(NO)(OR)_{2}] (R = Me, Et, Pr^n, Bu^n). The new complexes were analyzed by IR and ^1H-NMR spectroscopy.


Thermodynamic Studies Of Some Complexes Of 2-Benzoylpyridine 4-Phenyl-3-Thiosemicarbazone, T. Atalay, E. Güler Akgemci̇ Jan 1998

Thermodynamic Studies Of Some Complexes Of 2-Benzoylpyridine 4-Phenyl-3-Thiosemicarbazone, T. Atalay, E. Güler Akgemci̇

Turkish Journal of Chemistry

The stability constants of the Co(II), Ni(II), Cu(II) and Zn(II) complexes with 2-benzoylpyridine 4-phenyl-3-thiosemicarbazone were determined using a spectrophotometric method at different temperatures (25, 30, 35 and 40 $\pm$ 0.1^oC) and ionic strengths (0.05, 0.01 and 0.20 M KNO$_3$) in 50 \% (v/v) aqueous ethanol. Plots of thermodynamic stability constants at zero ionic strength ($\ln$ K^o) versus T$^{-1}$ gave linear curves and $\Delta$ H^o and $\Delta$ S^o were also calculated from these plots. Moreover, the changes in free energy for each metal-ligand system were calculated from the following equation. $\Delta$ G^o = -RT $\ln$ K^o.


The Removal Of Organic Sulfur From Two Turkish Lignites By Chlorinolysis, Yücel Y. Kadioğlu, Semra Karaca, Samih Bayrakçeken, M. Şahin Gülaboğlu Jan 1998

The Removal Of Organic Sulfur From Two Turkish Lignites By Chlorinolysis, Yücel Y. Kadioğlu, Semra Karaca, Samih Bayrakçeken, M. Şahin Gülaboğlu

Turkish Journal of Chemistry

The removal of organic sulfur from two Turkish lignites by chlorinolysis with chlorine gas in water and water-carbon tetrachloride media at ambient pressure was examined. The effects of stirring speed (5-20 s^{-1}), particle size (250-425, 150-180 and 74-88 \mu m), temperature (13-70°C) and time (0-10800 s) were investigated. Significant portions of the organic sulfur in the coal samples were removed.


Reaction Of 3,4-Diformyl-2,5-Dimethylpyrrole With 1,2(Substituted)Diphenyl-1,2-Diaminoethanes, Cemil Öğreti̇r, Fatma Severcan Jan 1998

Reaction Of 3,4-Diformyl-2,5-Dimethylpyrrole With 1,2(Substituted)Diphenyl-1,2-Diaminoethanes, Cemil Öğreti̇r, Fatma Severcan

Turkish Journal of Chemistry

3,4-Diformyl-2,5-dimethylpyrrole (1) reacts with 1,2-diphenyl-1,2-diamine derivatives to form the potentially tautomeric 2:2 macrocyclic adduct (1)=(1). ^1H and ^{13}C n.m.r. spectral data along with acidity measurements indicate that the 2-azafulvene structure (7) is predominant for all adducts.


The Adsorption Isotherms Of The Bleaching Of Sun Ower-Seed Oil, Hüseyin Topallar Jan 1998

The Adsorption Isotherms Of The Bleaching Of Sun Ower-Seed Oil, Hüseyin Topallar

Turkish Journal of Chemistry

In this study, the absorbance measurements were taken for the bleaching of sunflower-seed oil with wt. 0.3, 0.5, 0.7 and 0.9 % of clay at 60, 70, 80 and 90°C. Bentonite EY-09 was used as the bleaching clay. Since the heat evolved during adsorption (0.33-1.07 kJ mol^{-1}) was less than 20 kJ mol^{-1}, the forces between the adsorbent and adsorbate appear to be van der Waals forces, and this type of adsorption is physical or van der Waals adsorption. Thus, it was seen that the Freundlich equation was more applicable than the Langmuir equation to the experimental adsorption isotherms for …


Recovery Of Copper, Cobalt, Nickel, Cadmium, Zinc And Bismuth From Electrolytic Copper Solution, Fırat Aydin, Ömer Yavuz, Berrin Zi̇yadanoğullari, Recep Zi̇yadanoğullari Jan 1998

Recovery Of Copper, Cobalt, Nickel, Cadmium, Zinc And Bismuth From Electrolytic Copper Solution, Fırat Aydin, Ömer Yavuz, Berrin Zi̇yadanoğullari, Recep Zi̇yadanoğullari

Turkish Journal of Chemistry

An electrolytic Copper Solution (ECS) was electrolyzed using platinum electrodes. Copper was obtained in solid form. In order to precipitate Cd(II), Bi(III), As(III), Sb(III) and the rest of the Cu(II) ions, H_2S gas was passed through the remaining solution. The remaining solution was evaporated to obtain metal sulphates. The sample containing metal sulphates was roasted at temperatures between 550 and 800°C. Cobalt, nickel and zinc in the solid sample remained in the form of metal sulphates, while the iron in the sample was converted into Fe_2O_3. This solid sample was dissolved in water and filtered in order to crystallize the …


Potentiometric Titrations Of Semicarbazone Derivatives 6-Keto 9-17 Mono Methyl Substituted Octadecanoic Acids In Non-Aqueous Media, Mustafa Yalçin, Süleyman Tanyolaç, İrfan Kizilcikli, Aydın Tavman Jan 1998

Potentiometric Titrations Of Semicarbazone Derivatives 6-Keto 9-17 Mono Methyl Substituted Octadecanoic Acids In Non-Aqueous Media, Mustafa Yalçin, Süleyman Tanyolaç, İrfan Kizilcikli, Aydın Tavman

Turkish Journal of Chemistry

The pK$_a$ values of 6-semicarbazone 9-17 monomethyl substituted octadecanoic acids were determined using the potentiometric titration method. 2-Propanol was used as the non-aqueous medium and tetrabutylammonium hydroxide (TBAH) as the titrant in the experiments. The contribution of semicarbazone and methyl groups to the pK$_a$ values of octadecanoic acids was investigated and evaluated. In addition, observations were made on the IR spectra of the compounds.


Polymerization Of Pyrrole And Thiophene On Polyethylene Adipate Electrodes, Seyfettin Erturan, Burcu Yalvaç, Sena Toraman Jan 1998

Polymerization Of Pyrrole And Thiophene On Polyethylene Adipate Electrodes, Seyfettin Erturan, Burcu Yalvaç, Sena Toraman

Turkish Journal of Chemistry

Polymerizations of pyrrole and thiophene on a platinum foil coated by polyethylene adipate (PEA) were carried out in acetonitrile by electrochemical methods. Different compositions of semi-conducting composite films of PEA/Polypyrrole(PPy), PEA/Polythiophene(PT) were prepared by the electrochemical polymerization of pyrrole and thiophene on PEA electrode. The polymerization was possible only for a certain thickness of the polyethylene adipate(PEA) on the platinum. Conductivities of PEA/PPy, PEA/PT, films at different compositions were obtained. The films were examined by FTIR spectroscopy. The topography of surface films were analyzed by a scanning electron microscope(SEM). The conductivity behaviour of (PEA/PPy), (PEA/PT) films at different compositions when …


Effect Of Alkanols On The Micellar Behavior Of Chromium Laurate, Hüseyin Topallar, Yüksel Bayrak Jan 1998

Effect Of Alkanols On The Micellar Behavior Of Chromium Laurate, Hüseyin Topallar, Yüksel Bayrak

Turkish Journal of Chemistry

The critical micelle concentration, CMC, degree of dissociation, and dissociation constant of chromium laurate in alcohols (methanol, ethanol, propanol-1, butanol-1 and pentanol-1) were determined using conductometric measurements. The results show that chromium laurate behaves as simple electrolyte in dilute solutions below the CMC, and the conductance results can be explained according to Ostwald's formula and Debye-Huckel's theory of electrolytes.


Voltammetric Determination Of Salbutamol Based On Electrochemical Oxidation At Platinum And Glassy Carbon Electrodes, Niyazi Yilmaz, Sibel A. Özkan, Bengi Uslu, Zühre Şentürk, İnci Bi̇ryol Jan 1998

Voltammetric Determination Of Salbutamol Based On Electrochemical Oxidation At Platinum And Glassy Carbon Electrodes, Niyazi Yilmaz, Sibel A. Özkan, Bengi Uslu, Zühre Şentürk, İnci Bi̇ryol

Turkish Journal of Chemistry

The oxidative behavior of salbutamol was studied as a function of pH at platinum and activated glassy carbon electrodes. Between pH 1.9 and 12.0, the drug was characterized by a single oxidation step at both electrodes. The process was found to be dependent on the nature and the pH of the supporting elctrolyte. The procedure yielded a linear concentration range of $1 \times 10^{-4}$ to $1 \times 10^{-3}$ M and $2 \times 10^{-5}$ to $1 \times 10^{-3}$ M in 0.2 M sulphuric acid and a phosphate buffer of pH 6, at platinum and glassy carbon electrodes, respectively. The method was …


Cover And Contents Jan 1998

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Pixe, Particel Induced X-Ray Emission A Concise Review, A. İnhan Gari̇p Jan 1998

Pixe, Particel Induced X-Ray Emission A Concise Review, A. İnhan Gari̇p

Turkish Journal of Chemistry

PIXE-Particle Induced X-Ray Emission is a multielemental, sensitive and non-estructive method which has been in use in trace elemental analysis since 1970. This review aims to explain the main features of PIXE. References will be given at the end for those that seek more detailed knowledge on the principles and applications of this technique.


Theoretical Studies On The Configurations Of Benzhomobarrelene Derivatives, Rıza Abbasoğlu, Abdullah Menzek, Metin Balci Jan 1998

Theoretical Studies On The Configurations Of Benzhomobarrelene Derivatives, Rıza Abbasoğlu, Abdullah Menzek, Metin Balci

Turkish Journal of Chemistry

Reaction of 7-carbomethoxy-cycloheptatriene with benzyne resulted in the formation of only one benzhomobarrelene isomer, {\bf 5A}. Theoretically, four addition products, {\bf 5A-D}, can be formed from this reaction. Certain molecular mechanic calculations (MM2 force field) have been undertaken on these isomers. It has been shown that the isomers {\bf 5A} and {\bf 5C} have the lowest energies. The non-existence of {\bf 5C} has been discussed in terms of a benzyne approach to a norcaradiene structure. Furthermore, MM2 calculations on two different conformers of {\bf 5A} have revealed that the bisected conformer {\bf 5AE} has the highest strain energy. However, AM1 …


Determination Of The Protonation Constants Of 2-[4-Dimethylaminocinnamalamino] Benzoic Acid (Dacab) In Dioxane - Water Medium And Preparation Of Some Of Its Transition Metal Complexes, Mustafa Yalçin, Harun Mutluay, Hüsnü Cankurtaran Jan 1998

Determination Of The Protonation Constants Of 2-[4-Dimethylaminocinnamalamino] Benzoic Acid (Dacab) In Dioxane - Water Medium And Preparation Of Some Of Its Transition Metal Complexes, Mustafa Yalçin, Harun Mutluay, Hüsnü Cankurtaran

Turkish Journal of Chemistry

In this study, the Schiff base 2-[4-Dimethylaminocinnamalamino]- benzoic acid [(CH$_3$)$_2$N.C$_6$H$_4$.CH:CH.N.C$_6$H$_4$.COOH] (DACAB) was prepared by the reaction of 2-Aminobenzoic acid with p-Dimethylaminocinnamaldehyde. The protonation constants of the ligand were determined in a 50\% (v/v) dioxane - water medium using the Irving-Rossotti and PKAS-BEST computer methods. The complexes of Fe(III), Co(II), Ni(II), Cu(II) with DACAB were synthesized and the structures of these complexes were elucidated by means of data obtained from elemental analysis, using IR, $^1$H-NMR methods. The magnetic properties of the solid complexes were measured.


Indirect Complexometric Determination Of Mercury Using Potassium Iodide As Selective Masking Agent, B. Muralidhara Rao Jan 1998

Indirect Complexometric Determination Of Mercury Using Potassium Iodide As Selective Masking Agent, B. Muralidhara Rao

Turkish Journal of Chemistry

This paper describes a indirect complexometric method for the determination of mercury in the presence of co-ions, based on the selective masking ability of potassium iodide. To the mixture of mercury (II) and other metal ion solution, EDTA solution was added in excess of the metal ions present. The pH of the solution was adjusted to 5.0-6.0 using solid hexamine ($10 \pm 2$ g) and surplus EDTA was titrated with zinc sulfate solution using xylenol orange indicator. An excess of solid potassium iodide was then added to decompose the Hg-EDTA complex and the released EDTA was titrated with standard zinc …


Optimization Of Starting Time And Period Of Induction And Inducer Concentration In The Production Of The Restriction Enzyme Ecori From Recombinant Escherichia Coli 294, Candan Yildir Tamerler, Z. İlsen Önsan, Betül Kirdar Jan 1998

Optimization Of Starting Time And Period Of Induction And Inducer Concentration In The Production Of The Restriction Enzyme Ecori From Recombinant Escherichia Coli 294, Candan Yildir Tamerler, Z. İlsen Önsan, Betül Kirdar

Turkish Journal of Chemistry

Induction parameters including inducer concentration, period of induction and the cell concentration at which inducer is to be added to the fermentation broth were optimized in order to increase the yield of the {\em Eco}RI restriction endonuclease isolated from recombinant {\em E. coli}. Bacterial cells harboring the plasmid pPG430 containing {\em Eco}RI endonuclease and the methylase genes under the control of {\em lac} promoter were used in the experiments where induction was accomplished by using lactose isopropyl-$\beta$-D-thiogalactoside (IPTG). An IPTG concentration of 0.1mM, the late exponential phase of growth (at an optical density of 1.2 at 595 nm) and an …


Removal Of Water-Soluble Cationic Dyes With Trisyl Silicas, Erdener Karadağ, Dursun Saraydin, Fatma Aydin Jan 1998

Removal Of Water-Soluble Cationic Dyes With Trisyl Silicas, Erdener Karadağ, Dursun Saraydin, Fatma Aydin

Turkish Journal of Chemistry

In this study, the adsorption of certain water-soluble cationic dyes, (basic blue 9, basic blue 12, basic blue 17, brilliant cresyl blue, janus green B, basic green 4, basic violet 1, basic violet 3, and thionin) onto TriSyl silicas by batch adsorption at 25^oC was investigated. In the adsorption experiments, Langmuir type adsorption in the Giles classification system was found. Binding parameters such as the initial binding constant (K$_i$), the equilibrium binding constant (K), monolayer coverage(n), site-size(u), maximum fractional occupancy ($\hat{\theta}$), and the thermodynamic parameter free energy of adsorption $(\Delta G)$ were calculated for TriSyl silica and cationic dye systems …


Reactions Of 4-Amino-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones And 4-Amino-4h-1,2,4-Triazoles With Some Carboxylic Acid Anhydrides, Şule Bahçeci̇, Nurhan İnce, Asun İki̇zler Jan 1998

Reactions Of 4-Amino-4,5-Dihydro-1h-1,2,4-Triazol-5-Ones And 4-Amino-4h-1,2,4-Triazoles With Some Carboxylic Acid Anhydrides, Şule Bahçeci̇, Nurhan İnce, Asun İki̇zler

Turkish Journal of Chemistry

3-Alkyl(Aryl)-4-tetrachlorophthalimido-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) and 3-alkyl(aryl)-4-(1,8-naphthalimido)-4,5-dihydro-1H-1,2,4-triazol-5-ones (3) were synthesized from the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (1) with tetrachlorophthalic anhydride and 1,8-naphthalic anhydride, respectively. In addition, the reactions of 4-amino-4H-1,2,4-triazoles (4) with succinic anhydride and phthalic anhydride were studied.


Cu And Pb Adsorption On Some Bentonitic Clays, Oğuz İnel, Fehmi Albayrak, Ayşgül Aşkin Jan 1998

Cu And Pb Adsorption On Some Bentonitic Clays, Oğuz İnel, Fehmi Albayrak, Ayşgül Aşkin

Turkish Journal of Chemistry

Cu$^{2+}$ and Pb$^{2+}$ adsorption isotherms were measured on some clay samples obtained from various regions of Turkey. Also specific surface areas of clays were determined from adsorption data of ortho-phenanthroline(OP). The adsorptions of ions and OP were studied using the batch equilibration technique as a function of adsorbate concentration. The adsorption data, over the whole range of concentrations used, follow the Langmuir adsorption isotherm. The retention capacities of the adsorbates and the cation exchange capacities of the clays were determined. Plots of K$_d$, the distribution coefficient of ions between the solid and solution phases, vs. $\Gamma$, the surface density of …


The Effectof Lanthanum And Barium Additives On The Thermal Stabilization Of \Gamma-Al_2o_3, A. İnci İşli̇, A. Erhan Aksoylu, Z. İlsen Önsan Jan 1998

The Effectof Lanthanum And Barium Additives On The Thermal Stabilization Of \Gamma-Al_2o_3, A. İnci İşli̇, A. Erhan Aksoylu, Z. İlsen Önsan

Turkish Journal of Chemistry

The effect of La and Ba additives on the thermal stabilization of $\gamma$-Al$_2$O$_3$ was investigated through total-surface-area measurements. The parameters considered were additive content, calcination temperature, and calcination period. The effect of precalcination was also studied. It was found that thermal stabilization caused by 3 wt\% La and Ba is superior to 6 wt \% La or Ba, and the positive effect of 3 wt\% La and 3 wt\% Ba are almost identical. The nearly threefold increase in the total surface area of 3 wt\% La or Ba doped samples calcined above the $\gamma - \alpha$ phase-transition temperature indicates that …


Synthesis Of New Bisamidoxime Ligands And Their Monocharged Metal Complexes, Niyazi Biçak, Tülay Atay Jan 1998

Synthesis Of New Bisamidoxime Ligands And Their Monocharged Metal Complexes, Niyazi Biçak, Tülay Atay

Turkish Journal of Chemistry

This paper describes the synthesis of two new bisamidoxime ligands with dithioether connecting groups. The ligands were obtained from ethane dithiol in two steps; i) cyanoalkylation ii) oximation with hydroxylamine. Cyanoalkylation of ethanedithiol was carried out by condensing with chloro acetonitrile and base-catalysed addition of acrylonitrile, yielding bis(cyanomethylthio) ethane and bis(cyanoethyl thio) ethane, respectively. Upon subsequent oximation with hydroxylamine, these bisnitrile compounds gave corresponding bis(amidoxime) ligands in reasonable yields. The ligands behave as tetradentate ligands and on interaction with Cu(II), Ni(II), Co(II) chlorides produces monocharged metal complexes in a [ML]$^+$Cl$^-$ composition.


Gas Chromatography In The Low Concentration Determination Of Nitrous Oxide And Volatile Anaesthetics, Ahmet Uyanik Jan 1998

Gas Chromatography In The Low Concentration Determination Of Nitrous Oxide And Volatile Anaesthetics, Ahmet Uyanik

Turkish Journal of Chemistry

A previously reported single-column gas chromatographic separation method was modified for dual-detection gas chromatography (TCD+FID) and evaluated for the low concentration analysis of volatile anaesthetics (halothane, isoflurane) and nitrous oxide. It was found that no serious problem occurs in the determination of volatile anaesthetics with FID ($


Crystal Structure Of Dichlorodiaquabis-(P- Dimethylaminobenzaldehyde)Manganese(Ii), Veysel T. Yilmaz, Turan K. Yazicilar, Halis Ölmez, R. Alan Howie Jan 1998

Crystal Structure Of Dichlorodiaquabis-(P- Dimethylaminobenzaldehyde)Manganese(Ii), Veysel T. Yilmaz, Turan K. Yazicilar, Halis Ölmez, R. Alan Howie

Turkish Journal of Chemistry

The crystal structure of dichlorodiaquabis-($p$-dimethylaminobenzaldehyde)manganese(II), [MnCl$_2$(OH$_2$)$_2$(C$_9$H$_{11}$NO)$_2$], was determined from X-ray intensity data. The structure consists of the isolated molecules of the complex. The central Mn atom in the complex is coordinated by txo $p$-dimethylaminobenzaldehyde and two water molecules and also two chlorine atoms, resulting in a distorted octahedral environment. The same molecules or ions occupy {\it trans} positions. The crystal structure is stabilized by weak hydrogen bonds present between the isolated molecules.


Synthesis And Characterization Of Amorphous-Liquid Crystalline Poly(Vinyl Ether) Block Copolymers, İ. Ersin Serhatli, Müge Serhatli Jan 1998

Synthesis And Characterization Of Amorphous-Liquid Crystalline Poly(Vinyl Ether) Block Copolymers, İ. Ersin Serhatli, Müge Serhatli

Turkish Journal of Chemistry

A new series of amorphous-liquid crystalline poly(vinyl ether) block copolymers was synthesized using living cationic polymerization and free-radical polymerization techniques. Vinyl ether monomer was polymerized using a trifluoromethane sulfonic acid and methyl triflouoromethanesulfonate/tetrahydrothiophene initiator system in dichloromethane at -18^oC, and quantitatively terminated with labile azo compounds in order to obtain poly(vinyl ether) with well-defined molecular weight and end groups. This polymer was used in a subsequent blocking step in which azo groups were decomposed at 80^oC in the presence of methyl methacrylate and styrene monomer. In both copolymers, blocks of different chemical composition were segregated in the solid and melt-phase …


Potential Utilization Of Fusel Oil: A Kinetic Approach For Production Of Fusel Oil Esters Through Chemical Reaction, Zeki Küçücük, Kadim Ceylan Jan 1998

Potential Utilization Of Fusel Oil: A Kinetic Approach For Production Of Fusel Oil Esters Through Chemical Reaction, Zeki Küçücük, Kadim Ceylan

Turkish Journal of Chemistry

Fusel oil is a by-product of the distillation of ethyl alcohol from the fermentation of molasses and contains mainly C3-C5 alcohols. Acetic acid and butyric acid esters of its major alcohol components have economic value as chemicals for flavor and fragrance manufacturing. This study presents some data regarding the uncatalyzed esterification of fusel oil with acetic acid, propionic acid and butyric acid. The reactions were carried out at two temperatures, i.e., $45^{\circ}$C and under the reflux conditions ($80-85^{\circ}$C). The composition of raw fusel oil and the reaction mixtures were determined by gas chromatography. The reaction rate constants for the formation …