Negar Zekri

College of Chemistry and Chemical Engineering, Malek-Ashtar University of Technology, Tehran, 16765-3454, I. R. Iran.

[ 1 ] - Spinel ferrites as efficient magnetically reusable nanocatalysts in the solvent-free synthesis of substituted trisphenols

A series of copper and cobalt substituted nanospinel ferrites have been synthesized by the hydrothermal method. These compounds were characterized by FT-IR, XRD, EDX, SEM and VSM techniques. All of the synthesized nanospinel ferrites were found to be highly efficient and magnetically recoverable in the solvent-free synthesis of substituted 2,6-(2-hydroxybenzyl)-phenols (trisphenols). A wide ran...

[ 2 ] - Synthesis of substituted trisphenols by use of a double acidic ionic liquid under solvent-free conditions

3-methyl-1-(4-sulfobuthyl)-1-H-imidazol-3ium hydrogen sulfate, as a dual acidic ionic liquid (DAIL), was found to be an efficient catalyst for the simple, rapid and green synthesis of substituted trisphenols from the condensation of different substituted phenols and 2,6-bis (methylol) phenols (BMP). DAIL catalyst efficiently promoted the reaction between phenols and BMPs with a variety of funct...

[ 3 ] - Magnetic amine-functionalized graphene oxide as a novel and recyclable bifunctional nanocatalyst for solvent-free synthesis of pyrano[3,2-c]pyridine derivatives

The new magnetic amine-functionalized graphene oxide (Fe3O4-GO-NH2) nanocatalyst was prepared through the reaction of 3-aminopropyltriethoxysilane (APTES) with magnetic graphene oxide (Fe3O4-GO). It was characterized by XRD, TEM, SEM, FT-IR and EDX techniques. The intrinsic carboxylic acids on the edges of Fe3O4-GO alo...

[ 4 ] - مروری بر روش‌های سنتز آلکیل‌آزیدها و کاربردهای آنها در صنایع نظامی

Azide compounds have vast applications in military and civilian industries. Some of their applications include use in drug or drug intermediate production, macro cyclic polymer production through click reaction, automobile airbag production, energetic binders such as GAP,  oxidizer, plasticizer and burning rate control additive in solid composite propellants. Due to the wide range of appli...

[ 5 ] - یک روش نوین و کارآمد جهت سنتزترکیب 1و4- بوتان دی اُل به عنوان عامل گسترش دهنده زنجیره

The aim of this -study is the synthesis of 1,4-butanediol (BDO), as chain extender, which is a component of the propellant for improving its mechanical properties. In this research a new and efficient method for the synthesis of BDO from 2-bromoethanol has been reported. In roder to do this, first , the hydroxyl group of 2-bromoethanol was protected by triphenylmethyl chloride (TrCl). Then the ...

[ 6 ] - سنتز نرم‌کننده پرانرژی N- بوتیل-N - (2- نیتروکسی اتیل) نیترآمین (بوتیل ننا) در حضور مایعات یونی اسیدی قابل بازیافت

Use of energetic plasticizer, N-Butyl-N-(2-Nitroxyethyl) Nitramine (BuNENA), in the propellants’ formulations, has some advantages such as not migration in the fuel, high thermal stability, low sensitivity of the propellant formulation, improvement in mechanical properties and raising the impulse due to light molecular weight of combustion gases. In this study two acidic ionic liquids ([(...

[ 7 ] - روشی کارآمد جهت سنتز 4,2-دی نیتروتولوئن از طریق نیتراسیون انتخابی تولوئن و مشتقات آن در حضور مایعات یونی اسیدی جدید

Plasticizers are compounds which add to solid propellants’ formulations to improve their mechanical properties. These materials have key role in the control of mechanical properties. 2,4-Dinitrotoluene (2,4-DNT) is one of the most important plasticizers of double based propellants. In this study, new series of Brønsted acidic ionic liquids (ILs) have been prepared and introduced as...

[ 8 ] - مطالعه خواص مکانیکی و سرعت سوزش یک نمونه پیشرانه جامد دو پایه با پایدارکننده‌های آکاردیتII،سانترالیتI و یا 2 نیترو دی فنیل آمین

Mechanical properties and burning rate are very important parameters for solid propellants. In this work, the effects of quality and quantity of stabilizers as AkarditeII, 2-NDPA and CentraliteI on the Mechanical properties and burning rate of double-based is investigated. The results showed that, by CentraliteI increased mechanical properties of propellant and for AkarditeII and 2-NDPA stabili...

[ 9 ] - An Improvement to the Properties of GAP Binder with Energetic Ionic Liquids

Glycidyl azide polymer (GAP) is used as a binder in the propellants. Energetic ionic liquids are used as a plasticizer to correct the properties of polymer. In this study, first ionic liquid was bonded to the GAP by certain amount and then the energetic anions of nitrate (NO3) and azide (N3) were used to exchange anion. FTIR analyses confirm accurately anions exchange. DSC, viscometer and heat ...

[ 10 ] - Spinel ferrites as efficient magnetically reusable nanocatalysts in the solvent-free synthesis of substituted trisphenols

A series of copper and cobalt substituted nanospinel ferrites have been synthesized by the hydrothermal method. These compounds were characterized by FT-IR, XRD, EDX, SEM and VSM techniques. All of the synthesized nanospinel ferrites were found to be highly efficient and magnetically recoverable in the solvent-free synthesis of substituted 2,6-(2-hydroxybenzyl)-phenols (trisphenols). A wide ran...

[ 11 ] - Synthesis of substituted trisphenols by use of a double acidic ionic liquid under solvent-free conditions

3-methyl-1-(4-sulfobuthyl)-1-H-imidazol-3ium hydrogen sulfate, as a dual acidic ionic liquid (DAIL), was found to be an efficient catalyst for the simple, rapid and green synthesis of substituted trisphenols from the condensation of different substituted phenols and 2,6-bis (methylol) phenols (BMP). DAIL catalyst efficiently promoted the reaction between phenols and BMPs with a variety of funct...

[ 12 ] - بررسی پتانسیل مایعات یونی به عنوان جایگزین احتمالی برای نرم کننده های متداول در پیشرانه ها

Considering the role of plasticizers in the processability of solid propellants, recently many researches have been carried out on the development and investigation of the role of these plasticizers on the improvement of the propellants’ properties. These compounds are used in the formulation of double base and composite propellants to improve processability during propellant preparation and th...

[ 13 ] - بررسی تأثیر نرم کننده پرانرژی مایع یونی بر پایه ایمیدازولیوم بر خواص حرارتی نیتروسلولز

In this paper investigates an energetic imidazolium ionic liquid plasticizer (ILP)  effect on the degradation kinetics of nitrocellulose, which is a important component of double based solid propellants. For better comparison and evaluation, diethyl phthalate (DEP) plasticizer, which has a structure similar to ILP, was also evaluated. Heat of combustion analysis was performed to evaluate the en...