A. Tuncer Erciyes | İSTANBUL TEKNİK ÜNİVERSİTESİ (original) (raw)

Papers by A. Tuncer Erciyes

Research paper thumbnail of キク科のOnopordum tauricum Willd.及びバラ科の西洋バクチノキ(Prunus laurocerasus L.)の種子油の特性

Research paper thumbnail of Vaporization from liquid film of binary mixture in a centrifugal molecular still

Journal of Chemical Engineering of Japan, 1989

Research paper thumbnail of The decomposition of secondary esters of castor oil with fatty acids

Journal of the American Oil Chemists' Society, Sep 1, 1991

Research paper thumbnail of The kinetics of the esterification reaction between castor oil and oleic acid

Journal of the American Oil Chemists' Society, Sep 1, 1991

Research paper thumbnail of Aqueous polymerization of acrylamide initiated by 4,4′-azobis (4-cyano pentanol) and chain extension of polyacrylamide by means of ceric ion redox systems

Polymer Bulletin, 1992

The polymerization of acrylamide (AA) initiated by 4,4'-azobis (4 cyanopentanol) ... more The polymerization of acrylamide (AA) initiated by 4,4'-azobis (4 cyanopentanol) (ACP) was investigated in aqueous solution at 60°C. The molecular weight and the conversion depend on polymerization duration and initiator concentration. Polymerization of AA initiated by ACP yields polyacrylamide (PAA) with hydroxyl terminal groups. Redox polymerization of AA initiated by hydroxyl terminated PAA in conjuction with Ce(IV) provided increase in

Research paper thumbnail of Drying and semidrying oil macromonomers. III. Styrenation of sunflower and linseed oils

Journal of Applied Polymer Science, Mar 17, 2003

Styrenation of drying and semidrying oils, namely sunflower and linseed oils, via the macromer te... more Styrenation of drying and semidrying oils, namely sunflower and linseed oils, via the macromer technique was studied. For this purpose, the macromonomers of the oils were prepared by transesterification of methyl methacrylate (MMA) with the corresponding partial glycerides (PG). Subsequent styrenation was achieved by free radical copolymerization of the macromonomers with sty-rene using benzoyl peroxide as the initiator. The viscosity and the film properties of the products were studied and compared.

Research paper thumbnail of Optimum operating condition of Petlyuk's distillation process for ternary separation

Journal of Chemical Engineering of Japan, 1987

Research paper thumbnail of Fruit oils of four plant species of Turkish origin

Journal of the American Oil Chemists' Society, Oct 1, 1989

Research paper thumbnail of Heavy metal removal by ion exchanger based on hydroxyethyl cellulose

Journal of Applied Polymer Science, Dec 27, 1999

In the present work, ion exchange resin based on hydroxyethyl cellulose has been synthesized to r... more In the present work, ion exchange resin based on hydroxyethyl cellulose has been synthesized to remove the heavy metals, such as iron, cobalt, copper, and zinc from their aqueous solutions. The conditions in the column and batch modes were investigated for this purpose. The resin, having an average swelling percentage of 75.94 and an exchange capacity of 2.57 meq g−1 resin, is being introduced as a new ion exchange resin in the heavy metal removal process. An investigation of the column operations using aqueous solutions of heavy metal ions indicated that the resin prepared has some advantages, including high total exchange capacity and good chemical stability. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3501–3506, 1999

Research paper thumbnail of Enzymatic hydrolysis of anchovy oil: Production of glycerides enriched in polyunsaturated fatty acids

Applied Biochemistry and Biotechnology, Dec 1, 1997

In an attempt to produce the polyunsaturated fatty acid (PUFA)-enriched glycerides, commercially ... more In an attempt to produce the polyunsaturated fatty acid (PUFA)-enriched glycerides, commercially available Turkish anchovy oil (PUFA content of 27%), was hydrolyzed with 1,3-specific Rhizomucor miehei lipase. After the hydrolysis, the triglyceride (TG), diglyceride (DG), monoglyceride (MG), and free fatty acid (FFA) composition of the reaction mixture was determined, and fatty acid components of these fractions were analyzed. R. miehei lipase released PUFA extremely slowly, resulting in their accumulation in the TG and DG fractions, especially in TG. The PUFA content in the glyceride mixture (including TG, DG, and MG) increased as hydrolysis progressed. The effects of operational parameters (pH, temperature, time, and enzyme concentration) on the extent of hydrolysis were investigated. Based on these results, optimal reaction conditions were established. At optimal conditions (pH 4.0, 35 degrees C, 3 h, and enzyme concentration of 500 U/g oil), the level of PUFA in the glyceride mixture was raised to 40%. The individual TG and DG fractions contained 45 and 30% PUFA, respectively. Less than 2% of the total PUFA was lost in the FFA fraction.

Research paper thumbnail of <i>In situ</i>Synthesis of Oil Based Polymer Composites Containing Silver Nanoparticles

Journal Of Macromolecular Science, Part A, Jul 1, 2008

Using electron transfer reaction and free radical polymerization processes a series of triglyceri... more Using electron transfer reaction and free radical polymerization processes a series of triglyceride oil based polymer-silver nanocomposites were successfully prepared. The whole process was divided into two simultaneous stages; (i) copolymerization of macromonomers obtained from partial glycerides with styrene and (ii) the reduction of silver nitrate to metallic silver nano particles with radicals stemming from the thermolysis of 2,2 0-azoisobutyronitrile (AIBN). Nanocomposites were characterized by TEM and TGA. The obtained polymer nanocomposite was also examined in view of antibacterial effect against Gram-positive, Gram-negative, and Spore forming bacteria. It was demonstrated that nanocomposite samples exhibited an antibacterial effect against these bacteria. Film properties of the samples as potential coating material were also studied. Nanocomposite samples showed better film properties than that of the polymer without silver nanoparticles.

Research paper thumbnail of Oil-modified alkyd type resin based on secondary esters of castor oil

Journal of Coatings Technology, 1993

This study investigates the preparation of an oil-modified alkyd resin, starting from secondary e... more This study investigates the preparation of an oil-modified alkyd resin, starting from secondary esters of castor oil. Secondary esters of castor oil with mixed fatty acids of sunflower oil were subjected to thermal splitting. Partial glycerides resulting from the reaction between the thermal splitting mixture and glycerol were reacted with phthalic anhydride to obtain the proposed oil-modified alkyd resin. Due to the occurrence of diene conjugation on the ricinoleic acid chain during thermal splitting, this process can be viewed as an alternate way of preparing an alkyd resin partially modified with dehydrated castor oil

Research paper thumbnail of Kinetics of Esterification Reaction between Glycerol and Oleic Acid in the Presence of Pyridine

Fette, Seifen, Anstrichmittel, 1995

In this study the kinetics of esterification reaction between glycerol and oleic acid was investi... more In this study the kinetics of esterification reaction between glycerol and oleic acid was investigated in the presence of pyridine as a cosolvent, ~~~~~j~~ was carried a t 180y-, 2 0 0 0~ and 2 2 0 0~ using equivalent proportion of the reactants. A second-order rate equation Kinetik der Esterbildung zwischen Glycerin und dlsaure bei Anwesenheit von Pyridin In der vorliegenden Arbeit wurde die Kinetik der Reaktion zwischen Glycerin und dlsdure bei Anwesenheit von Pyridin als Losungsmittel untersucht. Die Reaktionen wurden bei 180"C, 200°C und 2 2 0 0~ Reaktanden durchgeffihrt. ~i~ Re&gleichen Anteilen was fitted to the experimental data Bt 1800c while a third-order rate tionsgeschwindigkeit bei 180°C laDt sich durch eineGleichung 2. Grades darstellen. Fur die iibrigen Temperaturen gelten Gleichungen 3. equation was fitted for the data obtained at the other temperatures. Grades.

Research paper thumbnail of Seed Oil Characteristics of <i>Onopordum tauricum</i> Willd. and <i>Prunus laurocerasus</i> L

Fette, Seifen, Anstrichmittel, 1995

ABSTRACT The characteristics of fatty oils recovered from seeds of Onopordum tauricum Willd. and ... more ABSTRACT The characteristics of fatty oils recovered from seeds of Onopordum tauricum Willd. and Prunus laurocerasus L. have been investigated. Gas chromatographic analysis showed that linoleic and oleic acids are predominant component fatty acids of Onopordum tauricum and Prunus laurocerasus seed oils, respectively. In view of technological evaluation, Onopordum tauricum seed oil can be regarded as a semidrying oil while the other shows characteristics of a nondrying oil.Charakteristische Eigenschaften der Samenöle von Onopordum tauricum Willd. und Prunus laurocerasus L.Die Zusammensetzung der Fettsäuren von Onopordum tauricum Willd. und Prunus laurocerasus L. wurde untersucht. Die gaschromatographische Analyse zeigte, daß in Onopordum tauricum und in Prunus laurocerasus Linolsäure und Ölsäure die Hauptkomponenten sind. In technischer Hinsicht ist das Öl von Onopordum tauricum als halbtrocknend anzusehen. Demgegenüber besitzt das Öl von Prunus laurocerasus einen nichttrocknenden Charakter.

Research paper thumbnail of Styrenation of triglyceride oils by macromonomer technique

Journal of Coatings Technology, 2000

Research paper thumbnail of Effects of Lewis acid catalysts on the esterification kinetics of castor oil with oleic acid

Journal of the American Oil Chemists' Society, Sep 1, 1994

The effects of two Lewis acid catalysts, tin chloride and cobalt chloride, on the kinetics of the... more The effects of two Lewis acid catalysts, tin chloride and cobalt chloride, on the kinetics of the esterification reaction between castor oil and oleic acid have been investigated. Uncatalyzed and catalyzed reactions were carried out both in the presence of excess oil and with equivalent amounts of reactants at various temperatures. The reaction, with respect to castor oil concentration, is first-order in all cases, whereas with acid concentration the reaction was observed to change from second-order for the uncatalyzed reaction to first-order for tin chloride-catalyzed and to zero-order for cobalt chloride-catalyzed reactions. The order {with respect to acid} also changed with temperature for the cobalt chloride-catalyzed reaction.

Research paper thumbnail of Mechanism and kinetics of the CoCl2‐catalyzed esterification reaction of castor oil with oleic acid

Journal of the American Oil Chemists' Society, 1995

The apparent orders of the Lewis acid‐catalyzed esterification reactions between castor oil and o... more The apparent orders of the Lewis acid‐catalyzed esterification reactions between castor oil and oleic acid are known to change with the catalyst used and with the reaction temperature. A mechanism is proposed in this study to explain the variations (with temperature) in the apparent orders of the cobalt chloride‐catalyzed esterification reaction between castor oil and oleic acid. According to the proposed mechanism, an acid‐catalyst intermediate forms in an initial, fast quasi‐equilibrium step, and this intermediate then reacts with the oil to yield the products and to regenerate the catalyst in the rate‐determining second step. A general rate expression, with an acid concentration term and a temperature‐dependent constant in the denominator, is derived from the proposed mechanism and is verified with data obtained at different temperatures.

Research paper thumbnail of Study of film properties of some urethane oils

Journal of Coatings Technology, 2002

O ne of the most widely used type of organic coatings is urethane oil which is produced by the re... more O ne of the most widely used type of organic coatings is urethane oil which is produced by the reaction of isocyanate with hydroxyl containing oil derivatives. Urethane oils can be considered as an alkyd resin in which the phthalic anhydride is replaced by a diisocyanate. In the ...

Research paper thumbnail of Biodiesel production from castor oil by transesterification reaction and investigation of the fuel properties

Research paper thumbnail of Effect of sonication on the synthesis of exfoliated polymer clay nanocomposites

Zenodo (CERN European Organization for Nuclear Research), Sep 1, 2019

Research efforts on polymer clay nanocomposites have been drawing a great deal of attention due t... more Research efforts on polymer clay nanocomposites have been drawing a great deal of attention due to their great enhancement of properties in many areas. Here, we synthesized exfoliated polymer clay nanocomposites (PCNs) by in situ polymerization of oil based vinyl macromonomer with styrene in the presence of clay. In order to facilitate the clay dispersion mixing was carried out by sonication besides classical mixing. The polymer clay nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction spectroscopy (XRD) and thermal gravimetric analysis (TGA). The samples prepared by mixing in sonication bath gave lower char yield compared to the samples of classical mixing.

Research paper thumbnail of キク科のOnopordum tauricum Willd.及びバラ科の西洋バクチノキ(Prunus laurocerasus L.)の種子油の特性

Research paper thumbnail of Vaporization from liquid film of binary mixture in a centrifugal molecular still

Journal of Chemical Engineering of Japan, 1989

Research paper thumbnail of The decomposition of secondary esters of castor oil with fatty acids

Journal of the American Oil Chemists' Society, Sep 1, 1991

Research paper thumbnail of The kinetics of the esterification reaction between castor oil and oleic acid

Journal of the American Oil Chemists' Society, Sep 1, 1991

Research paper thumbnail of Aqueous polymerization of acrylamide initiated by 4,4′-azobis (4-cyano pentanol) and chain extension of polyacrylamide by means of ceric ion redox systems

Polymer Bulletin, 1992

The polymerization of acrylamide (AA) initiated by 4,4&amp;amp;#39;-azobis (4 cyanopentanol) ... more The polymerization of acrylamide (AA) initiated by 4,4&amp;amp;#39;-azobis (4 cyanopentanol) (ACP) was investigated in aqueous solution at 60°C. The molecular weight and the conversion depend on polymerization duration and initiator concentration. Polymerization of AA initiated by ACP yields polyacrylamide (PAA) with hydroxyl terminal groups. Redox polymerization of AA initiated by hydroxyl terminated PAA in conjuction with Ce(IV) provided increase in

Research paper thumbnail of Drying and semidrying oil macromonomers. III. Styrenation of sunflower and linseed oils

Journal of Applied Polymer Science, Mar 17, 2003

Styrenation of drying and semidrying oils, namely sunflower and linseed oils, via the macromer te... more Styrenation of drying and semidrying oils, namely sunflower and linseed oils, via the macromer technique was studied. For this purpose, the macromonomers of the oils were prepared by transesterification of methyl methacrylate (MMA) with the corresponding partial glycerides (PG). Subsequent styrenation was achieved by free radical copolymerization of the macromonomers with sty-rene using benzoyl peroxide as the initiator. The viscosity and the film properties of the products were studied and compared.

Research paper thumbnail of Optimum operating condition of Petlyuk's distillation process for ternary separation

Journal of Chemical Engineering of Japan, 1987

Research paper thumbnail of Fruit oils of four plant species of Turkish origin

Journal of the American Oil Chemists' Society, Oct 1, 1989

Research paper thumbnail of Heavy metal removal by ion exchanger based on hydroxyethyl cellulose

Journal of Applied Polymer Science, Dec 27, 1999

In the present work, ion exchange resin based on hydroxyethyl cellulose has been synthesized to r... more In the present work, ion exchange resin based on hydroxyethyl cellulose has been synthesized to remove the heavy metals, such as iron, cobalt, copper, and zinc from their aqueous solutions. The conditions in the column and batch modes were investigated for this purpose. The resin, having an average swelling percentage of 75.94 and an exchange capacity of 2.57 meq g−1 resin, is being introduced as a new ion exchange resin in the heavy metal removal process. An investigation of the column operations using aqueous solutions of heavy metal ions indicated that the resin prepared has some advantages, including high total exchange capacity and good chemical stability. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3501–3506, 1999

Research paper thumbnail of Enzymatic hydrolysis of anchovy oil: Production of glycerides enriched in polyunsaturated fatty acids

Applied Biochemistry and Biotechnology, Dec 1, 1997

In an attempt to produce the polyunsaturated fatty acid (PUFA)-enriched glycerides, commercially ... more In an attempt to produce the polyunsaturated fatty acid (PUFA)-enriched glycerides, commercially available Turkish anchovy oil (PUFA content of 27%), was hydrolyzed with 1,3-specific Rhizomucor miehei lipase. After the hydrolysis, the triglyceride (TG), diglyceride (DG), monoglyceride (MG), and free fatty acid (FFA) composition of the reaction mixture was determined, and fatty acid components of these fractions were analyzed. R. miehei lipase released PUFA extremely slowly, resulting in their accumulation in the TG and DG fractions, especially in TG. The PUFA content in the glyceride mixture (including TG, DG, and MG) increased as hydrolysis progressed. The effects of operational parameters (pH, temperature, time, and enzyme concentration) on the extent of hydrolysis were investigated. Based on these results, optimal reaction conditions were established. At optimal conditions (pH 4.0, 35 degrees C, 3 h, and enzyme concentration of 500 U/g oil), the level of PUFA in the glyceride mixture was raised to 40%. The individual TG and DG fractions contained 45 and 30% PUFA, respectively. Less than 2% of the total PUFA was lost in the FFA fraction.

Research paper thumbnail of <i>In situ</i>Synthesis of Oil Based Polymer Composites Containing Silver Nanoparticles

Journal Of Macromolecular Science, Part A, Jul 1, 2008

Using electron transfer reaction and free radical polymerization processes a series of triglyceri... more Using electron transfer reaction and free radical polymerization processes a series of triglyceride oil based polymer-silver nanocomposites were successfully prepared. The whole process was divided into two simultaneous stages; (i) copolymerization of macromonomers obtained from partial glycerides with styrene and (ii) the reduction of silver nitrate to metallic silver nano particles with radicals stemming from the thermolysis of 2,2 0-azoisobutyronitrile (AIBN). Nanocomposites were characterized by TEM and TGA. The obtained polymer nanocomposite was also examined in view of antibacterial effect against Gram-positive, Gram-negative, and Spore forming bacteria. It was demonstrated that nanocomposite samples exhibited an antibacterial effect against these bacteria. Film properties of the samples as potential coating material were also studied. Nanocomposite samples showed better film properties than that of the polymer without silver nanoparticles.

Research paper thumbnail of Oil-modified alkyd type resin based on secondary esters of castor oil

Journal of Coatings Technology, 1993

This study investigates the preparation of an oil-modified alkyd resin, starting from secondary e... more This study investigates the preparation of an oil-modified alkyd resin, starting from secondary esters of castor oil. Secondary esters of castor oil with mixed fatty acids of sunflower oil were subjected to thermal splitting. Partial glycerides resulting from the reaction between the thermal splitting mixture and glycerol were reacted with phthalic anhydride to obtain the proposed oil-modified alkyd resin. Due to the occurrence of diene conjugation on the ricinoleic acid chain during thermal splitting, this process can be viewed as an alternate way of preparing an alkyd resin partially modified with dehydrated castor oil

Research paper thumbnail of Kinetics of Esterification Reaction between Glycerol and Oleic Acid in the Presence of Pyridine

Fette, Seifen, Anstrichmittel, 1995

In this study the kinetics of esterification reaction between glycerol and oleic acid was investi... more In this study the kinetics of esterification reaction between glycerol and oleic acid was investigated in the presence of pyridine as a cosolvent, ~~~~~j~~ was carried a t 180y-, 2 0 0 0~ and 2 2 0 0~ using equivalent proportion of the reactants. A second-order rate equation Kinetik der Esterbildung zwischen Glycerin und dlsaure bei Anwesenheit von Pyridin In der vorliegenden Arbeit wurde die Kinetik der Reaktion zwischen Glycerin und dlsdure bei Anwesenheit von Pyridin als Losungsmittel untersucht. Die Reaktionen wurden bei 180"C, 200°C und 2 2 0 0~ Reaktanden durchgeffihrt. ~i~ Re&gleichen Anteilen was fitted to the experimental data Bt 1800c while a third-order rate tionsgeschwindigkeit bei 180°C laDt sich durch eineGleichung 2. Grades darstellen. Fur die iibrigen Temperaturen gelten Gleichungen 3. equation was fitted for the data obtained at the other temperatures. Grades.

Research paper thumbnail of Seed Oil Characteristics of <i>Onopordum tauricum</i> Willd. and <i>Prunus laurocerasus</i> L

Fette, Seifen, Anstrichmittel, 1995

ABSTRACT The characteristics of fatty oils recovered from seeds of Onopordum tauricum Willd. and ... more ABSTRACT The characteristics of fatty oils recovered from seeds of Onopordum tauricum Willd. and Prunus laurocerasus L. have been investigated. Gas chromatographic analysis showed that linoleic and oleic acids are predominant component fatty acids of Onopordum tauricum and Prunus laurocerasus seed oils, respectively. In view of technological evaluation, Onopordum tauricum seed oil can be regarded as a semidrying oil while the other shows characteristics of a nondrying oil.Charakteristische Eigenschaften der Samenöle von Onopordum tauricum Willd. und Prunus laurocerasus L.Die Zusammensetzung der Fettsäuren von Onopordum tauricum Willd. und Prunus laurocerasus L. wurde untersucht. Die gaschromatographische Analyse zeigte, daß in Onopordum tauricum und in Prunus laurocerasus Linolsäure und Ölsäure die Hauptkomponenten sind. In technischer Hinsicht ist das Öl von Onopordum tauricum als halbtrocknend anzusehen. Demgegenüber besitzt das Öl von Prunus laurocerasus einen nichttrocknenden Charakter.

Research paper thumbnail of Styrenation of triglyceride oils by macromonomer technique

Journal of Coatings Technology, 2000

Research paper thumbnail of Effects of Lewis acid catalysts on the esterification kinetics of castor oil with oleic acid

Journal of the American Oil Chemists' Society, Sep 1, 1994

The effects of two Lewis acid catalysts, tin chloride and cobalt chloride, on the kinetics of the... more The effects of two Lewis acid catalysts, tin chloride and cobalt chloride, on the kinetics of the esterification reaction between castor oil and oleic acid have been investigated. Uncatalyzed and catalyzed reactions were carried out both in the presence of excess oil and with equivalent amounts of reactants at various temperatures. The reaction, with respect to castor oil concentration, is first-order in all cases, whereas with acid concentration the reaction was observed to change from second-order for the uncatalyzed reaction to first-order for tin chloride-catalyzed and to zero-order for cobalt chloride-catalyzed reactions. The order {with respect to acid} also changed with temperature for the cobalt chloride-catalyzed reaction.

Research paper thumbnail of Mechanism and kinetics of the CoCl2‐catalyzed esterification reaction of castor oil with oleic acid

Journal of the American Oil Chemists' Society, 1995

The apparent orders of the Lewis acid‐catalyzed esterification reactions between castor oil and o... more The apparent orders of the Lewis acid‐catalyzed esterification reactions between castor oil and oleic acid are known to change with the catalyst used and with the reaction temperature. A mechanism is proposed in this study to explain the variations (with temperature) in the apparent orders of the cobalt chloride‐catalyzed esterification reaction between castor oil and oleic acid. According to the proposed mechanism, an acid‐catalyst intermediate forms in an initial, fast quasi‐equilibrium step, and this intermediate then reacts with the oil to yield the products and to regenerate the catalyst in the rate‐determining second step. A general rate expression, with an acid concentration term and a temperature‐dependent constant in the denominator, is derived from the proposed mechanism and is verified with data obtained at different temperatures.

Research paper thumbnail of Study of film properties of some urethane oils

Journal of Coatings Technology, 2002

O ne of the most widely used type of organic coatings is urethane oil which is produced by the re... more O ne of the most widely used type of organic coatings is urethane oil which is produced by the reaction of isocyanate with hydroxyl containing oil derivatives. Urethane oils can be considered as an alkyd resin in which the phthalic anhydride is replaced by a diisocyanate. In the ...

Research paper thumbnail of Biodiesel production from castor oil by transesterification reaction and investigation of the fuel properties

Research paper thumbnail of Effect of sonication on the synthesis of exfoliated polymer clay nanocomposites

Zenodo (CERN European Organization for Nuclear Research), Sep 1, 2019

Research efforts on polymer clay nanocomposites have been drawing a great deal of attention due t... more Research efforts on polymer clay nanocomposites have been drawing a great deal of attention due to their great enhancement of properties in many areas. Here, we synthesized exfoliated polymer clay nanocomposites (PCNs) by in situ polymerization of oil based vinyl macromonomer with styrene in the presence of clay. In order to facilitate the clay dispersion mixing was carried out by sonication besides classical mixing. The polymer clay nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction spectroscopy (XRD) and thermal gravimetric analysis (TGA). The samples prepared by mixing in sonication bath gave lower char yield compared to the samples of classical mixing.