Shahram Mehdipour-Ataei | Iran Polymer And Petrocchemical Institute (original) (raw)

Papers by Shahram Mehdipour-Ataei

Organic-Inorganic Composite Polymer Electrolyte Membranes, 2017

Electrospinning is a low-cost versatile process with relatively high production rate for preparat... more Electrospinning is a low-cost versatile process with relatively high production rate for preparation of nanofibers that can be used in various fields. As the structure of electrospun mats is very similar to human tissues and organs, most of research activities in electrospinning are dedicated to biomedical applications. However, another interesting field for application of electrospun membranes is fuel cell application. The focus of this chapter is on the membrane of polymeric fuel cells and the methods of using electrospinning process for preparation of the membranes. Three important objectives of using electrospinning in membranes of polymeric fuel cells are reducing methanol crossover, improving proton conductivity, and suppressing water swelling, which will be explained in detail.

Polymers for Advanced Technologies, 2016

Journal of Polymer Science Part A: Polymer Chemistry, 2015

International Journal of Polymeric Materials and Polymeric Biomaterials, 2014

The main drawback of direct methanol fuel cells is methanol crossover. One strategy to overcome t... more The main drawback of direct methanol fuel cells is methanol crossover. One strategy to overcome this problem is design of new polymeric membranes. Two structurally different diols named as 4,4′-(1,4-phenylene diisopropylidene) bisphenol and 4,4′-(1,3-phenylene diisopropylidene) bisphenol (para- and meta-substituted monomers) were used to prepare two groups of poly(arylene ether sulfone)s with different structures and related membranes therefrom by solution casting. It was found that para- or meta-substitution positions in monomers affected the methanol permeability of membranes. Other influenced properties of resulted membranes such as ion exchange capacity, water uptake, proton conductivity, glass transition temperature, and mechanical strength were studied and compared. GRAPHICAL ABSTRACT

Polymers for Advanced Technologies, 2007

Abstract A new diamine monomer containing flexible sulfone, sulfide, and amide units was prepared... more Abstract A new diamine monomer containing flexible sulfone, sulfide, and amide units was prepared via three steps. Nucleophilic chloro displacement reaction of 4-aminothiophenol with 4-nitrobenzoyl chloride in the presence of propylene oxide afforded N-(4-mercapto-...

European Polymer Journal, 2005

European Polymer Journal, 2007

A new-type of sulfide containing diacid (1,1 0 -thiobis(2-naphthoxy acetic acid)) was synthesized... more A new-type of sulfide containing diacid (1,1 0 -thiobis(2-naphthoxy acetic acid)) was synthesized from 2-naphthol in three steps. Reaction of 2-naphthol with sulfur dichloride afforded 1,1 0 -thiobis(2-naphthol) (TBN). 1,1 0 -Thiobis(2-naphthoxy acetic ester) (TBNAE) was successfully synthesized by refluxing the TBN with methylcholoroacetate in the presence of potassium carbonate. The related diacid was synthesized by basic solution reduction of TBNAE. The obtained diacid was fully characterized and used to prepare novel thermally stable poly(sulfide ether amide)s via polyphosphorylation reaction with different aromatic diamines. The properties of these new polyamides were investigated and compared with similar polyamides. These polyamides showed inherent viscosities in the range of 0.39-0.87 dL g À1 in N,N-dimethylacetamide (DMAc) at 30 °C and at a concentration of 0.5 g dL À1 . All the polyamides were readily soluble in a variety of polar solvents such as DMAc and tetrahydrofuran (THF). These polyamides showed glass transition temperature (T g ) between 241-268 °C. Thermogravimetric analysis measurement revealed the decomposition temperature at 10% weight loss (T 10 ) ranging from 441-479 °C in argon atmosphere.

e-Polymers, 2009

The nitro group of 4-(p-nitrobenzyl)pyridine was converted to amino group and 4-(p-aminobenzyl)py... more The nitro group of 4-(p-nitrobenzyl)pyridine was converted to amino group and 4-(p-aminobenzyl)pyridine was prepared by catalytic hydrogenation using hydrazine hydrate/Pd-C systemReaction of 4-(p-aminobenzyl)pyridine with 1,3,5-benzenetricarboxylic acid under appropriate conditions yielded a new diacid containing amide group and pyridine unit. The prepared substances were characterized using FT-IR, H-NMR, and mass spectroscopy and also elemental analysis. Polycondensation reactions of the diacid with different commercially available diols in the presence of benzenesulfonyl chloride afforded new types of poly(amide-ester)s. All the polymers were characterized and their physical and thermal properties were studied. The polymers showed high thermal stability and also enhanced solubility in polar aprotic solvents.

Catalysts

Mesoporous carbon materials have attracted both academic and industrial interests because of thei... more Mesoporous carbon materials have attracted both academic and industrial interests because of their outstanding physical and chemical properties, such as high surface area, large pore-volume, good thermostability, improved mass transport, and diffusion. Mesoporous carbon materials with various pore sizes and pore structures can be synthesized via different methods. Their unique properties have made them a suitable choice for various applications, such as energy-storage batteries, supercapacitors, biosensors, fuel cells, adsorption/separation of various molecules, catalysts/catalyst support, enzyme immobilization, and drug delivery, in different fields. This review covers the fabrication techniques of mesoporous carbon structures and their typical applications in various fields and features a brief introduction of the functionalization and modification of mesoporous carbons.

Eco-friendly and Smart Polymer Systems, 2020

A novel aromatic diamine containing pyridine unit was prepared via two-step reactions. Nucleophil... more A novel aromatic diamine containing pyridine unit was prepared via two-step reactions. Nucleophilic substitution of oxydianiline with 6-chloronicotinoyl chloride led to preparation of a dichloro-diamide compound. Subsequent reaction of this compound with 3-aminophenol resulted in synthesis of a particular diamine. After complete characterization, polycondensation reaction of the diamine with terephthaloyl chloride and isophthaloyl chloride led to preparation of related polyamides. The polymers were characterized and their physical and thermal properties were studied.

Eco-friendly and Smart Polymer Systems, 2020

A novel aromatic diamine containing pyridine units, amide, and ether groups was generated via two... more A novel aromatic diamine containing pyridine units, amide, and ether groups was generated via two-step reactions: nucleophilic substitution reaction of oxydianiline with 6-chloronicotinoyl chloride led to preparation of a dichloro compound. Subsequent reaction of this compound with 4-aminophenol resulted in synthesis of the particular diamine. After characterization, polycondensation reaction of the diamine with different dianhydrides led to preparation of related poly(ether-amide-imide)s. The nicotinic-based poly(etheramide-imide)s showed high heat resistance and improved solubility in polar solvents.

Studies in fuel cell membranes show that modification of polyimides by introduction of aliphatic ... more Studies in fuel cell membranes show that modification of polyimides by introduction of aliphatic linkages in the structure of sulfonated copolyimides, synthesis of branched/ crosslinked sulfonated polyimides, and semi and fully interpenetrating polymer networks of sulfonated polyimides restrain suitable potential for Nafion substitution. a 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

The advances in proton exchange membranes (PEM)s is critical for improving the performance of fue... more The advances in proton exchange membranes (PEM)s is critical for improving the performance of fuel cells [1]. Membranes compromising perfluorosulfonic acid polymers such as Nafion have been used extensively due to their desired conductivity and stability. However, these materials need to be saturated with water to obtain practical level of proton conductivity. There is a strong demand for the PEMs to work at lower relative humidity or under anhydrous conditions because the electrochemical reactions will be accelerated and water management of fuel cell will be simpler. Various designing strategies and advanced materials have been developed to mitigate for this issue without causing serious loss in proton conductivity or stability [2]. Among all, the introducing of inorganic proton conductors such as heteropoly acids have been considered widely. Generally, HPAs (such as phosphotungstic acid H3PW12O40, PWA) have a very strong Bronsted acidity approaching the superacid region (more acid...

Arabian Journal of Chemistry, 2017

Carbon-based catalysts are gained significant interest for improving a number of catalytic proces... more Carbon-based catalysts are gained significant interest for improving a number of catalytic processes due to their unique set of benefits. However, a few of such catalysts are proper for synthesis of organic compounds in water. Therefore, there is a strong need for developing water-tolerant and dispersible catalysts. Here, we demonstrate a simple and efficient method for the preparation of highly dispersible phosphonic acid functionalized carbocatalyst. The applied functionalization method was flexible in controlling the functionalization level. The prepared nanocatalyst exhibited superior catalytic performance toward multicomponent synthesis of pyrano[2,3-c]pyrazole, with 80-90% yield within 15 min in water. Moreover, this water-tolerant solid acid catalyst could be simply retrieved and after 6 successive cycles of reactions, the reaction time and yield still keeps within the same level.

Designed Monomers and Polymers, 2016

Direct copolymerization of sulfonated and non-sulfonated difluorodiphenyl sulfones as dihalide mo... more Direct copolymerization of sulfonated and non-sulfonated difluorodiphenyl sulfones as dihalide monomers with hydroquinone and also 4,4′-(4,4′-sulfonylbis-(1,4-phenylene)bis(oxy)) diphenol as diols led to preparation of two series of poly(arylene ether sulfone)s. Copolymers with different degrees of sulfonation (40, 50 and 60%) were synthesized in order to evaluate their potential for fuel cell application. 1 H-NMR, FT-IR, and mass spectroscopy were used for characterization of prepared monomers and copolymers. Differential scanning calorimetry and thermogravimetric analysis were applied for investigation and comparison of the thermal properties of copolymers. Laser light scattering (LLS) was employed to calculate zeta potential, conductivity, and molecular weight of copolymers. Copolymers were obtained in high and sufficient molecular weight that was basic need to reach reasonable physical and thermal properties for applications as fuel cell membrane. The effect of similar structural repeating units with different sizes on the final properties of sulfonated poly(ether sulfone)s was investigated to compare their potential in fuel cell membrane.

Designed Monomers and Polymers, 2016

The aim of study was to prepare novel polyamides with improved solubility and processability with... more The aim of study was to prepare novel polyamides with improved solubility and processability without sacrifice of their thermal and mechanical properties. Polyamides containing ether and sulfone units were obtained via condensation of a special diamine with various diacid chlorides. Poly(ether ether sulfone amide)s were obtained in good inherent viscosities ranging from 0.72 to 0.84 dL/g. All the polyamides were amorphous and readily soluble in polar solvents and swelled in CH 2 Cl 2 and tetrahydrofuran. Flexible films of polymers were obtained by solution casting. Polyamide films exhibited good mechanical and thermal stability including the temperature for 10% weight loss of 449-476 °C.

RSC Advances, 2015

In this study, nanocomposite blends of fully sulfonated poly(ether ketone) (PEK) and non-sulfonat... more In this study, nanocomposite blends of fully sulfonated poly(ether ketone) (PEK) and non-sulfonated poly(ether sulfone) (PES) were prepared from a dual electrospinning process.

Designed Monomers and Polymers, 2015

A sulfone ether diamine was synthesized by three-step reactions. Firstly, 4-(4-nitrophenoxy) phen... more A sulfone ether diamine was synthesized by three-step reactions. Firstly, 4-(4-nitrophenoxy) phenol was synthesized via nucleophilic substitution reaction of 1-fluoro-4-nitrobenzene with hydroquinone in the presence of K 2 CO 3 in NMP. In the second step, 4-(4-nitrophenoxy) phenol was reduced to 4-(4-aminophenoxy) phenol by Pd/activated carbon catalyst in ethanolic hydrazine hydrate. Finally, 4-(4-aminophenoxy) phenol was reacted with 4,4′-dichlorodiphenyl sulfone (with 2:1 M ratio) to produce the sulfone ether diamine. Then three different kinds of poly(sulfone ether imide)s were prepared by solution polycondensation of synthesized diamine with commercially available aromatic dianhydrides including pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, and hexafluoroisopropylidene diphthalic anhydride. The structure of synthesized compounds, monomers, and prepared polymers was characterized using 1 H NMR and FT-IR spectroscopy and also elemental analysis method. Thermal behavior and stability, solubility, solution viscosity, mechanical properties, crystallinity, water uptake, and optical properties of samples were studied.

Designed Monomers and Polymers, 2015

Reactions of 3-aminophenol with dichlorodiphenylsilane in the presence of triethylamine resulted ... more Reactions of 3-aminophenol with dichlorodiphenylsilane in the presence of triethylamine resulted in the preparation of a diamine named as bis(m-aminophenoxy)diphenylsilane. Reaction of the diamine with two moles of trimellitic anhydride led to the preparation of a diacid with preformed imide structures. Silicon-containing poly(amide-imide)s were then prepared by polycondensation reactions of the diacid with different diamines in the presence of triphenyl phosphite. All the products and polymers were characterized and the physical properties of the polymers including solubility, solution viscosity, thermal stability, thermal behavior, flameretardency, crystallinity, and morphology were studied. The polymers showed high thermal stability and flameretardency, as well as enhanced solubility in polar solvents. The glass transition temperature of the polymers was about 187-196°C, the temperature for 10% gravimetric loss was in the range of 375-400°C, and also the weight of the polymer remaining at 700°C was about 39-44%. They were flame-retardant, soluble in dipolar aprotic solvents, and showed some crystalline structures.

Polymers for Advanced Technologies, 2008

New sulfonated aromatic copolyimides with controlled degree of sulfonation were prepared via poly... more New sulfonated aromatic copolyimides with controlled degree of sulfonation were prepared via polycondensation reactions of a sulfonated diamine and two unsulfonated diamines with 1,4,5,8-naphthalene tetracarboxylic dianhydride (NDA). The sulfonated diamine 3,3(-disulfonic acidbis[4-(5-amino-1-naphthoxy)phenyl]sulfone (DANPS) was synthesized through nucleophilic substitution reaction of 5-amino-1-naphthol with disodium-3,3(-disulfonate-4,4(-dichlorodiphenysulfone (SDCDPS) and subsequent acidification. Two unsulfonated diamines 4,4(-(5-amino-1-naphthoxy)diphenylsulfone (ANDS) and 4,4(-(4-aminophenoxy)diphenylsulfone (APDS) were prepared by nucleophilic reaction of 5-amino-1-naphthol and 4-aminophenol with 4,4(-dichlorodiphenylsulfone in the presence of potassium carbonate, respectively. After characterization of the monomers and polymers with common methods, the physical properties of the polymers including thermal behavior and stability, viscosity, molecular weight, and ion exchange capacity (IEC) were studied. The polymers showed high thermal stability and ion exchange capacity which were the basic requirements for application as fuel cell membranes.

Organic-Inorganic Composite Polymer Electrolyte Membranes, 2017

Electrospinning is a low-cost versatile process with relatively high production rate for preparat... more Electrospinning is a low-cost versatile process with relatively high production rate for preparation of nanofibers that can be used in various fields. As the structure of electrospun mats is very similar to human tissues and organs, most of research activities in electrospinning are dedicated to biomedical applications. However, another interesting field for application of electrospun membranes is fuel cell application. The focus of this chapter is on the membrane of polymeric fuel cells and the methods of using electrospinning process for preparation of the membranes. Three important objectives of using electrospinning in membranes of polymeric fuel cells are reducing methanol crossover, improving proton conductivity, and suppressing water swelling, which will be explained in detail.

Polymers for Advanced Technologies, 2016

Journal of Polymer Science Part A: Polymer Chemistry, 2015

International Journal of Polymeric Materials and Polymeric Biomaterials, 2014

The main drawback of direct methanol fuel cells is methanol crossover. One strategy to overcome t... more The main drawback of direct methanol fuel cells is methanol crossover. One strategy to overcome this problem is design of new polymeric membranes. Two structurally different diols named as 4,4′-(1,4-phenylene diisopropylidene) bisphenol and 4,4′-(1,3-phenylene diisopropylidene) bisphenol (para- and meta-substituted monomers) were used to prepare two groups of poly(arylene ether sulfone)s with different structures and related membranes therefrom by solution casting. It was found that para- or meta-substitution positions in monomers affected the methanol permeability of membranes. Other influenced properties of resulted membranes such as ion exchange capacity, water uptake, proton conductivity, glass transition temperature, and mechanical strength were studied and compared. GRAPHICAL ABSTRACT

Polymers for Advanced Technologies, 2007

Abstract A new diamine monomer containing flexible sulfone, sulfide, and amide units was prepared... more Abstract A new diamine monomer containing flexible sulfone, sulfide, and amide units was prepared via three steps. Nucleophilic chloro displacement reaction of 4-aminothiophenol with 4-nitrobenzoyl chloride in the presence of propylene oxide afforded N-(4-mercapto-...

European Polymer Journal, 2005

European Polymer Journal, 2007

A new-type of sulfide containing diacid (1,1 0 -thiobis(2-naphthoxy acetic acid)) was synthesized... more A new-type of sulfide containing diacid (1,1 0 -thiobis(2-naphthoxy acetic acid)) was synthesized from 2-naphthol in three steps. Reaction of 2-naphthol with sulfur dichloride afforded 1,1 0 -thiobis(2-naphthol) (TBN). 1,1 0 -Thiobis(2-naphthoxy acetic ester) (TBNAE) was successfully synthesized by refluxing the TBN with methylcholoroacetate in the presence of potassium carbonate. The related diacid was synthesized by basic solution reduction of TBNAE. The obtained diacid was fully characterized and used to prepare novel thermally stable poly(sulfide ether amide)s via polyphosphorylation reaction with different aromatic diamines. The properties of these new polyamides were investigated and compared with similar polyamides. These polyamides showed inherent viscosities in the range of 0.39-0.87 dL g À1 in N,N-dimethylacetamide (DMAc) at 30 °C and at a concentration of 0.5 g dL À1 . All the polyamides were readily soluble in a variety of polar solvents such as DMAc and tetrahydrofuran (THF). These polyamides showed glass transition temperature (T g ) between 241-268 °C. Thermogravimetric analysis measurement revealed the decomposition temperature at 10% weight loss (T 10 ) ranging from 441-479 °C in argon atmosphere.

e-Polymers, 2009

The nitro group of 4-(p-nitrobenzyl)pyridine was converted to amino group and 4-(p-aminobenzyl)py... more The nitro group of 4-(p-nitrobenzyl)pyridine was converted to amino group and 4-(p-aminobenzyl)pyridine was prepared by catalytic hydrogenation using hydrazine hydrate/Pd-C systemReaction of 4-(p-aminobenzyl)pyridine with 1,3,5-benzenetricarboxylic acid under appropriate conditions yielded a new diacid containing amide group and pyridine unit. The prepared substances were characterized using FT-IR, H-NMR, and mass spectroscopy and also elemental analysis. Polycondensation reactions of the diacid with different commercially available diols in the presence of benzenesulfonyl chloride afforded new types of poly(amide-ester)s. All the polymers were characterized and their physical and thermal properties were studied. The polymers showed high thermal stability and also enhanced solubility in polar aprotic solvents.

Catalysts

Mesoporous carbon materials have attracted both academic and industrial interests because of thei... more Mesoporous carbon materials have attracted both academic and industrial interests because of their outstanding physical and chemical properties, such as high surface area, large pore-volume, good thermostability, improved mass transport, and diffusion. Mesoporous carbon materials with various pore sizes and pore structures can be synthesized via different methods. Their unique properties have made them a suitable choice for various applications, such as energy-storage batteries, supercapacitors, biosensors, fuel cells, adsorption/separation of various molecules, catalysts/catalyst support, enzyme immobilization, and drug delivery, in different fields. This review covers the fabrication techniques of mesoporous carbon structures and their typical applications in various fields and features a brief introduction of the functionalization and modification of mesoporous carbons.

Eco-friendly and Smart Polymer Systems, 2020

A novel aromatic diamine containing pyridine unit was prepared via two-step reactions. Nucleophil... more A novel aromatic diamine containing pyridine unit was prepared via two-step reactions. Nucleophilic substitution of oxydianiline with 6-chloronicotinoyl chloride led to preparation of a dichloro-diamide compound. Subsequent reaction of this compound with 3-aminophenol resulted in synthesis of a particular diamine. After complete characterization, polycondensation reaction of the diamine with terephthaloyl chloride and isophthaloyl chloride led to preparation of related polyamides. The polymers were characterized and their physical and thermal properties were studied.

Eco-friendly and Smart Polymer Systems, 2020

A novel aromatic diamine containing pyridine units, amide, and ether groups was generated via two... more A novel aromatic diamine containing pyridine units, amide, and ether groups was generated via two-step reactions: nucleophilic substitution reaction of oxydianiline with 6-chloronicotinoyl chloride led to preparation of a dichloro compound. Subsequent reaction of this compound with 4-aminophenol resulted in synthesis of the particular diamine. After characterization, polycondensation reaction of the diamine with different dianhydrides led to preparation of related poly(ether-amide-imide)s. The nicotinic-based poly(etheramide-imide)s showed high heat resistance and improved solubility in polar solvents.

Studies in fuel cell membranes show that modification of polyimides by introduction of aliphatic ... more Studies in fuel cell membranes show that modification of polyimides by introduction of aliphatic linkages in the structure of sulfonated copolyimides, synthesis of branched/ crosslinked sulfonated polyimides, and semi and fully interpenetrating polymer networks of sulfonated polyimides restrain suitable potential for Nafion substitution. a 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

The advances in proton exchange membranes (PEM)s is critical for improving the performance of fue... more The advances in proton exchange membranes (PEM)s is critical for improving the performance of fuel cells [1]. Membranes compromising perfluorosulfonic acid polymers such as Nafion have been used extensively due to their desired conductivity and stability. However, these materials need to be saturated with water to obtain practical level of proton conductivity. There is a strong demand for the PEMs to work at lower relative humidity or under anhydrous conditions because the electrochemical reactions will be accelerated and water management of fuel cell will be simpler. Various designing strategies and advanced materials have been developed to mitigate for this issue without causing serious loss in proton conductivity or stability [2]. Among all, the introducing of inorganic proton conductors such as heteropoly acids have been considered widely. Generally, HPAs (such as phosphotungstic acid H3PW12O40, PWA) have a very strong Bronsted acidity approaching the superacid region (more acid...

Arabian Journal of Chemistry, 2017

Carbon-based catalysts are gained significant interest for improving a number of catalytic proces... more Carbon-based catalysts are gained significant interest for improving a number of catalytic processes due to their unique set of benefits. However, a few of such catalysts are proper for synthesis of organic compounds in water. Therefore, there is a strong need for developing water-tolerant and dispersible catalysts. Here, we demonstrate a simple and efficient method for the preparation of highly dispersible phosphonic acid functionalized carbocatalyst. The applied functionalization method was flexible in controlling the functionalization level. The prepared nanocatalyst exhibited superior catalytic performance toward multicomponent synthesis of pyrano[2,3-c]pyrazole, with 80-90% yield within 15 min in water. Moreover, this water-tolerant solid acid catalyst could be simply retrieved and after 6 successive cycles of reactions, the reaction time and yield still keeps within the same level.

Designed Monomers and Polymers, 2016

Direct copolymerization of sulfonated and non-sulfonated difluorodiphenyl sulfones as dihalide mo... more Direct copolymerization of sulfonated and non-sulfonated difluorodiphenyl sulfones as dihalide monomers with hydroquinone and also 4,4′-(4,4′-sulfonylbis-(1,4-phenylene)bis(oxy)) diphenol as diols led to preparation of two series of poly(arylene ether sulfone)s. Copolymers with different degrees of sulfonation (40, 50 and 60%) were synthesized in order to evaluate their potential for fuel cell application. 1 H-NMR, FT-IR, and mass spectroscopy were used for characterization of prepared monomers and copolymers. Differential scanning calorimetry and thermogravimetric analysis were applied for investigation and comparison of the thermal properties of copolymers. Laser light scattering (LLS) was employed to calculate zeta potential, conductivity, and molecular weight of copolymers. Copolymers were obtained in high and sufficient molecular weight that was basic need to reach reasonable physical and thermal properties for applications as fuel cell membrane. The effect of similar structural repeating units with different sizes on the final properties of sulfonated poly(ether sulfone)s was investigated to compare their potential in fuel cell membrane.

Designed Monomers and Polymers, 2016

The aim of study was to prepare novel polyamides with improved solubility and processability with... more The aim of study was to prepare novel polyamides with improved solubility and processability without sacrifice of their thermal and mechanical properties. Polyamides containing ether and sulfone units were obtained via condensation of a special diamine with various diacid chlorides. Poly(ether ether sulfone amide)s were obtained in good inherent viscosities ranging from 0.72 to 0.84 dL/g. All the polyamides were amorphous and readily soluble in polar solvents and swelled in CH 2 Cl 2 and tetrahydrofuran. Flexible films of polymers were obtained by solution casting. Polyamide films exhibited good mechanical and thermal stability including the temperature for 10% weight loss of 449-476 °C.

RSC Advances, 2015

In this study, nanocomposite blends of fully sulfonated poly(ether ketone) (PEK) and non-sulfonat... more In this study, nanocomposite blends of fully sulfonated poly(ether ketone) (PEK) and non-sulfonated poly(ether sulfone) (PES) were prepared from a dual electrospinning process.

Designed Monomers and Polymers, 2015

A sulfone ether diamine was synthesized by three-step reactions. Firstly, 4-(4-nitrophenoxy) phen... more A sulfone ether diamine was synthesized by three-step reactions. Firstly, 4-(4-nitrophenoxy) phenol was synthesized via nucleophilic substitution reaction of 1-fluoro-4-nitrobenzene with hydroquinone in the presence of K 2 CO 3 in NMP. In the second step, 4-(4-nitrophenoxy) phenol was reduced to 4-(4-aminophenoxy) phenol by Pd/activated carbon catalyst in ethanolic hydrazine hydrate. Finally, 4-(4-aminophenoxy) phenol was reacted with 4,4′-dichlorodiphenyl sulfone (with 2:1 M ratio) to produce the sulfone ether diamine. Then three different kinds of poly(sulfone ether imide)s were prepared by solution polycondensation of synthesized diamine with commercially available aromatic dianhydrides including pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, and hexafluoroisopropylidene diphthalic anhydride. The structure of synthesized compounds, monomers, and prepared polymers was characterized using 1 H NMR and FT-IR spectroscopy and also elemental analysis method. Thermal behavior and stability, solubility, solution viscosity, mechanical properties, crystallinity, water uptake, and optical properties of samples were studied.

Designed Monomers and Polymers, 2015

Reactions of 3-aminophenol with dichlorodiphenylsilane in the presence of triethylamine resulted ... more Reactions of 3-aminophenol with dichlorodiphenylsilane in the presence of triethylamine resulted in the preparation of a diamine named as bis(m-aminophenoxy)diphenylsilane. Reaction of the diamine with two moles of trimellitic anhydride led to the preparation of a diacid with preformed imide structures. Silicon-containing poly(amide-imide)s were then prepared by polycondensation reactions of the diacid with different diamines in the presence of triphenyl phosphite. All the products and polymers were characterized and the physical properties of the polymers including solubility, solution viscosity, thermal stability, thermal behavior, flameretardency, crystallinity, and morphology were studied. The polymers showed high thermal stability and flameretardency, as well as enhanced solubility in polar solvents. The glass transition temperature of the polymers was about 187-196°C, the temperature for 10% gravimetric loss was in the range of 375-400°C, and also the weight of the polymer remaining at 700°C was about 39-44%. They were flame-retardant, soluble in dipolar aprotic solvents, and showed some crystalline structures.

Polymers for Advanced Technologies, 2008

New sulfonated aromatic copolyimides with controlled degree of sulfonation were prepared via poly... more New sulfonated aromatic copolyimides with controlled degree of sulfonation were prepared via polycondensation reactions of a sulfonated diamine and two unsulfonated diamines with 1,4,5,8-naphthalene tetracarboxylic dianhydride (NDA). The sulfonated diamine 3,3(-disulfonic acidbis[4-(5-amino-1-naphthoxy)phenyl]sulfone (DANPS) was synthesized through nucleophilic substitution reaction of 5-amino-1-naphthol with disodium-3,3(-disulfonate-4,4(-dichlorodiphenysulfone (SDCDPS) and subsequent acidification. Two unsulfonated diamines 4,4(-(5-amino-1-naphthoxy)diphenylsulfone (ANDS) and 4,4(-(4-aminophenoxy)diphenylsulfone (APDS) were prepared by nucleophilic reaction of 5-amino-1-naphthol and 4-aminophenol with 4,4(-dichlorodiphenylsulfone in the presence of potassium carbonate, respectively. After characterization of the monomers and polymers with common methods, the physical properties of the polymers including thermal behavior and stability, viscosity, molecular weight, and ion exchange capacity (IEC) were studied. The polymers showed high thermal stability and ion exchange capacity which were the basic requirements for application as fuel cell membranes.