access article under the CC BY license:This is an open Al-Khwarizmi Engineering Journal Al-Khwarizmi Engineering Journal ISSN (printed): 1818 – 1171, ISSN (online): 2312 – 0789 Vol. 21, No. 3, September, (2025), pp. 12- 24 Examination the Corrosion Inhibition of Synthesized Azo-Schiff Bases Compounds from (P-Fluorophenyl)-1,3,4-Thiadiazoles for Carbon Steel Alloy in Acidic Medium Khadija Najah Zaidane 1*, and Ahmed Wahed Naser 2 1 Department of Petroleum Refining and Gas Technology Engineering, College of Chemical Engineering, University of Technology, Baghdad, Iraq 2 Department of Chemical Engineering, College of Engineering, University of Baghdad, Baghdad, Iraq *Corresponding Author’s Email: khadija89najahz@gmail.com (Received 28 July 2024; Revised 6 September 2024; Accepted 25 September 2024; Published 1 September 2025) https://doi.org/10.22153/kej.2025.09.004 Abstract New azo-Schiff base compounds were prepared by different processes using (p-fluorophenyl)-1,3,4-thiadiazoles, and their role as corrosion inhibitors for carbon steel alloy in acidic media such as 0.1 M HCl at 298 K was investigated. Spectroscopic methods such as FT-IR and NMR were used to characterise the compounds, and potentiodynamic polarization curves were employed to evaluate their corrosion inhibition. p-Aminoacetophenone was react withed 2-(5- (4-fluorophenyl)-1,3,4-thiadiazol-2-yl) acetohydrazide (A1) to prepare N ′ -(1-(4-aminophenyl) ethylidene)-2-(5-(4- fluorophenyl)-1,3,4-thiadiazol-2-yl) acetohydrazide (A2). Azo-Schiff bases (A3-A6) were synthesised by combining the prepared diazonium salts with different phenols. These compounds’ structures were changed to improve their ability to prevent corrosion in a range of industrial settings, especially for metals exposed to acidic environments. The inhibitory efficiency percentage was between 76% and 90%. At 90%, the synthetic medication (A6) obtained the highest value. The formed protective adsorption coating on the steel surface was the reason for the improved inhibitor activity. These findings imply that the artificial Azo-Schiff bases show promising application as corrosion inhibitors for carbon steel in acidic settings. Applications in sectors where corrosion resistance is crucial may benefit from this knowledge. Keywords: Potentiodynamic; Polarisation; Thiadiazol; Aminoacetophenone; Hydroxy naphthalene; Carbon steel; Fourier Transform Infrared Spectroscopy; Dimethyl sulfoxide. 1. Introduction The chemical, electricity and petroleum industries, frequently use iron and its alloys because of their low cost, strong mechanical properties and simplicity of manufacture [1, 2]. Many industries are affected by the expensive problem of corrosion, especially those that depend on metal parts and buildings that are subjected to severe conditions [3]. Thus, efficient corrosion prevention techniques must be developed. One method is to use anti- corrosion materials. Corrosion inhibitors are classified according to their chemical structure and mechanism, with organic inhibitors being the most common [4-6]. Chemicals known as corrosion inhibitors are used in extreme situations to lessen or prevent metal corrosion. These materials either alter the environment or apply a protective layer to the metal surface to stop corrosion [7]. Their application is essential in industries where metals are regularly subjected to harsh environments, such as those that are acidic, saline or rich in oxygen. Corrosion inhibitors are essential because they extend the life of metal structures, reduce maintenance and replacement costs and guarantee mailto:khadija89najahz@gmail.com https://doi.org/10.22153/kej.2025.09.004 Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 13 the safe and dependable operation of industrial systems. They slow down the deterioration of metals and stop the discharge of toxic byproducts into ecosystems, both of which contribute to environmental protection. Hence, they are essential to sectors including construction, chemical processing, water treatment and oil and gas [7-9]. Investigations demonstrated that organic inhibitors comprising heteroatoms such as oxygen, phosphorous, sulphur and nitrogen are exceptionally effective at lowering corrosion in a variety of acidic solutions. Owing to their high polarisability and low electronegativity, these inhibitors function by promoting electron transport to atoms’ vacant orbitals and enabling atoms and functional groups to cover substantial metallic surface regions [10]. Organic compounds, especially derivatives of thiadiazol, have recently attracted attention as possible corrosion inhibitors. Their distinctive molecular structures are characterised by a five- membered heterocyclic ring composed of sulphur and nitrogen atoms [11]. The inclusion of the (p- fluorophenyl) moiety increases the electron density of the thiadiazol ring and may enhance the adsorption characteristics of the resulting Azo- Schiff bases. In acidic media where metal corrosion is most severe, this structural alteration renders these compounds potent corrosion inhibitors [12]. N-heterocyclic compounds can effectively suppress iron or steel corrosion under a wide range of harsh conditions. Many strategies are used to counteract corrosion, each suited to different types of metals and surroundings. Important techniques include passivation, which encourages the production of a persistent oxide layer, mixed inhibition and adsorption inhibition, in which organic inhibitors are adsorbed onto metal surfaces to form protective barriers [13]. One of the best ways to prevent corrosion in metals is to employ inhibitors. Numerous methods have been used to investigate metal corrosion. One of the most practical ways to prevent corrosion in acidic conditions is to utilise chemical inhibitors [14]. The majority of highly effective acid inhibitors are made of organic substances containing sulphur, phosphorus, oxygen and nitrogen. Therefore, research on the connection between adsorption and corrosion inhibition is crucial [15]. The Schiff base, which is the product of the condensation of amines with aldehydes or ketones, has good inhibitive qualities. These ligands are remarkably members of the class in coordination chemistry. Their C=N groups are responsible for this ability. Schiff bases adhere to and shield the metal/solution surface. In this work, azo-Schiff base derivatives were studied to explore their corrosion inhibition of carbon steel in 0.1 M hydrochloric acid solution. Table 2 provides the chemical structures of these derivatives. The heteroatoms in the heterocyclic structure of Nʹ-(1-(4-((2-amino-4-hydroxyphenyl) diazenyl) phenyl) ethylidene)-2-((5-(4-fluorophenyl)-1,3,4- thiadiazol-2-yl) amino) acetohydrazide (A6) may function as an efficient corrosion inhibitor. Novel azo-Schiff bases were created using p-fluorophenyl- 1,3,4-thiadiazoles in order to prevent carbon steel from corroding in acidic settings at room temperature (298 K). 2. Materials and Methods 2.1. Chemicals and Materials All substances used were supplied by Merck, BDH, Fluka and Sigma–Aldrich Chemicals Companies, Germany. The alloy used in this work was carbon steel (C45) with the following chemical composition: Table 1, C45 Carbon steel’s chemical constitution Metal C% Si% Mn % S% P% Cu% Ni% Cr% Fe% Carbon Steel 45 0.36-0.42 0.15- 0.30 1.00- 1.40 0.05 0.05 0.50 0.20 0.20 96.88- 97.49 Bruker UltraShield 500 MHz spectrophotometer was used to record NMR (1H-NMR and 13C-NMR) spectral data with DMSO as a solvent at the University of Baghdad’s College of Sciences. A SHIMADZU FT-IR 8300 Fourier transform infrared spectrophotometer was used to calculate infrared spectra for the prepared derivatives as a KBr disc in the wave range of 400–4000 cm¯1. A hot stage Gallen Kamp melting point apparatus (m. p.) was used in an open capillary system to determine the melting point. An advanced potentiostat named MLab 200 (2007) bank (Electronic-intelligent controls GmbH) complete with all accessories and three electrode cells was used for polarisation measurements at the Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 14 University of Baghdad’s College of Science, Department of Chemistry. 2.2. Measurements and Experimental Setup 2.2.1. Experimental setup The corrosion inhibition of carbon steel using an organic inhibitor in 0.1 M HCl at 298 K was examined through potentiostat polarisation curves. The experimental setup involved carefully preparing carbon steel specimens by polishing, cleaning and drying to ensure uniformity. The specimens are immersed in an acidic corrosive solution containing the organic inhibitor. A three- electrode electrochemical cell comprising carbon steel as the working electrode, a saturated calomel electrode (SCE) as the reference electrode and platinum as the counter electrode was utilised. Polarisation curves were produced by applying a controlled potential sweep with a potentiostat to investigate anodic and cathodic reactions. The obtained polarisation curves were used to calculate the corrosion rate and effectiveness of the organic inhibitor by determining the corrosion potential (Ecorr), corrosion current density (Icorr) and other electrochemical parameters. As shown in Figure 1, this configuration offers a thorough assessment of how the organic inhibitor inhibits corrosion in acidic environments by affecting anodic and cathodic corrosion processes. Fig. 1. Complete system set-up for polarisation measurements An electrochemical cell known as the corrosion cell was used to experimentally evaluate the carbon steel specimens for electrochemical corrosion [16]. The 1 L Pyrex corrosion cell consisted of a three- electrode system whose electrodes (working, axillary and reference) were submerged in an electrolyte solution. (1) Working electrode: The carbon steel specimen served as an electrode during the operation. The metal was reduced or oxidised at the working electrode by an anodic or cathodic process. Studies on corrosion found these reactions to be of interest. (2) Axillary electrode: During the test, the working electrode where the cathodic or anodic reaction occurs was supplied with current by the axillary electrode, which is made of high-purity platinum metal. (3) Reference electrode: A calomel electrode was used to allow the potentiostat to regulate the voltage between the working and reference electrodes. The login tube serves as a salt bridge, minimises the potential drop caused by resistance at the interface between the working electrode and the electrolyte and controls the reference electrode’s ideal location. 2.2.2. Synthesis of inhibitors a) Synthesis of Nʹ-(1-(4-aminophenyl) ethylidene)- 2-((5-(4-fluorophenyl)-1,3,4-thiadiazol-2-yl) amino) acetohydrazide (A2) [17, 18]: 20 mL of 100% ethanol was used to dissolve compound (A1) (0.5 g, 0.001 mol). Glycolate acetic acid and p-aminoacetophenone were added in small amounts to this solution (0.03). For 10 hours, this combination underwent reflux. The precipitate was removed from the ethanol by filtering, drying and recrystallisation after cooling (A2) (85% yield, mature point (m. p.) 471.15 k– 473.15 k, yellow precipitation; m. p. 478.15 k– 480 k, yield 96%, yellow precipitate). Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 15 b) General synthesis method for azo-Schiff bases (A3–A6) [19, 20]: After dissolving compound A2 (0.007 mol) in 15 mL of concentrated HCl and 15 mL of distilled water, the mixture was cooled in an ice bath until it reached a temperature between 0 and 278.15 k. The NaNO2 solution, which was prepared by dissolving 0.47 g or 0.007 mol into 5 mL of distilled water, was dropwise added to the reaction mixture, which was then agitated for 10 minutes. The mixture was slowly and carefully added to a solution containing various phenols (0.007 mol) such as phenol, β-naphthol, p- nitrophenol, salcildehyde and 3-aminophenol in 60 mL of 10% NaOH at 0–278.15 k. The mixture was then agitated for 30 minutes. Hot steam was used to dry the coloured product after it was filtered and cleaned with cooled distilled water. Nʹ-(1-(4-((2-hydroxynaphthalen-1-yl) diazenyl) phenyl) ethylidene)-2-((5-(4-flourophenyl)-1,3,4- thiadiazol-2-yl) amino) acetohydrazide (A3): yield 70%, m. p. 363.15 k–365.15 k, burgundy precipitate Nʹ-(1-(4-((2-hydroxy-5-nitrophenyl) diazenyl) phenyl) ethylidene)-2-((5-(4-flourophenyl)-1, 3, 4- thiadiazol-2-yl) amino) acetohydrazide (A4): yield 80 %, m. p. 506.15 k–508.15 k, pale orange precipitate Nʹ-(1-(4-((3-formyl-4-hydroxyphenyl) diazenyl) phenyl) ethylidene)-2-((5-(4-flourophenyl)-1, 3, 4- thiadiazol-2-yl) amino) acetohydrazide (A5): yield 83%, gummy, greenish brown precipitate Nʹ-(1-(4-((2-amino-4-hydroxyphenyl) diazenyl) phenyl) ethylidene)-2-((5-(4-flouro phenyl)-1, 3, 4- thiadiazol-2-yl) amino) acetohydrazide (A6): yield 82%, m. p. 430.15 k–432.15 k, orange precipitate 2.3. Corrosion Measurement Carbon steel alloy was utilised, and its chemical composition is detailed in Table 1. Before the corrosion test, the carbon steel electrode underwent polishing with emery papers grade 800–1200. Distilled water, acetone and alcohol were used for ultrasonic cleaning, followed by drying in dry air. A 0.1 M HCl aqueous solution, the testing electrolyte, was prepared by diluting AnalaR grade 37% HCl with ultrapure water. Polarisation measurements were conducted using a standard corrosion cell. The setup included a corrosion cell with three electrodes: a working electrode made of carbon steel alloy, a counter electrode and a reference electrode SCE. All potential values were referenced to the SCE. Electrochemical experiments were performed over a potential range of 200 mV. Before measurements, the working electrode was immersed in the test solution for 900 seconds to achieve a steady-state open circuit potential (Eocp). All tests were carried out at 298 K using a cooling or heating circulating water bath [21]. 3. Results and Discussion 3.1. Synthesis and Analysis The Azo-Schiff base compounds produced from (p-fluorophenyl)-1,3,4-thiadiazoles were studied using analytical techniques, FT-IR and NMR. The FT-IR spectra of the compounds (A3–A6) in Figures 4–10 confirmed the formation of azo dyes via the appearance of a stretching band of OH at 3200–3433 cm−1 [3]. FT-IR spectral data also showed the appearance of a stretching band of N=N at 1425 cm−1. All details of the FTIR spectral data of compounds A3–A6 are listed in Table 2. The presence of distinctive C=N stretching vibrations in the FT-IR spectra verified the synthesis of Schiff bases. The molecular structure was revealed by NMR spectroscopy, which also verified that the p- fluorophenyl group was successfully incorporated into the 1,3,4-thiadiazole ring. Compounds A3 and A5) were identified by 1HNMR and 13CNMR: new values appeared at δ = 13.03–13.13 ppm attributed to the OH proton, and a new signal at δ = 1.13, 1.17 ppm indicated binding the (CH3) group of compounds (A3, A5). In contrast, the 13CNMR spectrum of compound A3 displayed characteristic signals δ (ppm) at 39.7, 154.38 and 170.34 attributed to CH3, (C-OH) and (C=N), receptively. The 1HNMR and 13CNMR spectra of compounds A3 and A5 are listed in Tables 3 and 4 and displayed in Figures 8–10. Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 16 Table 2, FTIR spectral data of compounds A3–A6 Com. NO. Str. FTIR spectral data cm-1 Ν (N-H) ν(C-H) aroma. Ν (C-H) alipha. ν(C=N) ν(C=O) ν(N=N) Others A3 3180 3064 2887 1623 1689 1425 (C-F) 1296 (OH) 3200 A4 3269 3064 2920 2854 1602 1687 1425 (C-F) 1292 (OH) 3433 A5 3101 3064 2960, 2827 1687 1604 1425 (C-F) 1286 A6 3200 3064 2960 2885 1687 1602 1425 (C-F) 1288 Table 3, 1HNMR spectral data (δ ppm) of compounds A3 and A5 Com. No. Structure 1HNMR spectral data (δ ppm) A3 1.13 (s, 3H, -CH3); 2.53 (d, 2H, -CH2); 7.80 (s, H, NH); 6.36-8.89 (m, 14H, CH-Ar); 13.13 (s, H, OH) A5 1.13 (s, 3H, -CH3); 2.8 (d, 2H, -CH2); 7.41 (s, H, NH); 6.36-8.58 (m, 14H, CH-Ar); 10.12 (s, H- C=O); 13.03 (s, H, OH) Table 4, 13CNMR spectral data (δ ppm) of compound A3 Com. Structure 13CNMR spectral data (δ ppm) A3 39.7 (CH3); 124.90-129.37 (C-Ar); 136.47 (C-CH3); 148.16 (C-F); 154.38 (C-OH); 170.34 (C=N) Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 17 3.2. Potentiodynamic Polarisation Measurements The corrosion inhibition performance of the synthesised compounds was evaluated by conducting potentiodynamic polarisation in acidic media. Table 2 shows that compared with that in the blank solution, the corrosion current density (Icorr) in the presence of the azo-Schiff base inhibitors significantly decrease from 563.2 µA/cm2 to 137.3, 102.0, 74.28 and 56.26 µA/cm2 for A4, A3, A6 and A5, respectively. The decrease in corrosion rate corresponded to an inhibitory efficiency percentage (IE%) of 90% for compound A5 as shown in Figure 2 and Table 5. %IE = (icorr)o−(icorr) (icorr)o ∗ 100, (1) where (i corr) is the corrosion current density in the absence of inhibitors, (icorr) is the corrosion current density in the presence of inhibitors [22, 23]. Figure 1 shows the polarisation curves of the blank and inhibited solutions with different synthesised compounds. The extent of rusting in 0.1 M HCl solution and the cathodic and anodic Tafel slopes in the presence and absence of the inhibitor molecules were extrapolated. The current corrosion density (Icorr) and corrosion potential (Ecorr) were calculated. Table 5 displays the calculated corrosion potential (Ecorr, mV), corrosion current density score (A/cm2), cathodic and anodic Tafel slopes (mV/Dec) and protection effectiveness PE% [24]. The corrosion potential (Ecorr) shifted to a more active potential for all the compounds, indicating a change in the natural surface. As a result, the inhibitors were adsorbed on the carbon steel surface. The anodic (ꞵa) and cathodic (ꞵc) slopes were changed significantly (Table 5 and Figure 2, indicating that the compounds act as a mixed-type inhibitor affecting anodic and cathodic reactions. Table 5, Corrosion parameters for blank and compound in HCl solutions and different compounds. Comp. Blank A3 A4 A5 A6 -Ecorr (V) -0.385 -0.717 -0.743 -0.862 -0.812 Icorr (µA/cm2) 563.2 102.0 137.3 56.26 74.28 I corr./ r )A/cm² ( 0.001 2.040E-4 2.747E-4 1.125E-4 1.486E-4 Resis. )Ω( 28.96 1209 955.8 1836 1842 -Bc (mV/Dec) 0.055 0.502 0.561 0.577 0.722 Ba (mV/Dec) 0.120 0.655 0.656 0.405 0.559 Corr. rate, (mm/y) 5.529 1.001 1.348 0.552 0.729 IE% - 82 76 90 87 Fig. 2. Polarisation curve of carbon steel in 0.1 M HCl and inhibited solutions with four synthesised compounds (A3, A4, A5 and A6) at 298 K 3.3. Mechanism of Inhibition The inhibitory effectiveness of the heteroatoms followed the sequence O < N < S, which is attributed to the presence of C=N groupings. Azo- Schiff bases demonstrate their inhibitory effectiveness mainly through their adsorption on the metal/solution interface [3, 25], creating a barrier Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 18 that keeps corrosive substances from getting to the metal. The lone pair electrons on the Schiff base’s nitrogen atoms and the π-electrons of the aromatic rings, which interact with the metal surface, are probably involved in the adsorption process. By increasing the electron density surrounding the Schiff base, the use of a p-fluorophenyl group leads to good adsorption and high inhibitory efficiency. Additionally, the p-fluorophenyl group’s electron- donating action is probably responsible for the observed rise and fall in Icorr values [26]. Scheme 1. Synthesis route of compounds A3–A6 Fig. 3. FTIR spectrum of compound A3 Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 19 Fig. 4. FTIR spectrum of compound A4 Fig. 5. FT-IR spectrum of compound A5 Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 20 Fig. 6. FT-IR spectrum of compound A6 Fig. 7. 1HNMR spectral data of compound A3 Fig. 8. 13CNMR spectrum of compound A3 Khadija Najah Zaidane Al-Khwarizmi Engineering Journal, Vol. 21, No.3, pp. 12- 24 (2025) 21 Fig. 9. 1HNMR spectrum of compound A5 4. Conclusions Azo-Schiff base compounds were synthesised from (p-fluorophenyl)-1,3,4-thiadiazoles, and their potential as potent corrosion inhibitors for metallic materials in acidic environments was assessed. Their structures were confirmed using FT-IR, ¹H NMR and ¹³C NMR. Compounds A3–A6 were evaluated for their capacity to prevent the surface corrosion of carbon steel in an acidic environment. These substances showed potent anticorrosive properties by forming an adsorbed layer on the carbon steel’s surface. The synthetic Azo-Schiff bases exhibited improved structural properties, particularly stability and adsorption capacity for the p-fluorophenyl moiety on the metal substrate. 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( 2025) 12-24، صفحة 3، العدد21مجلة الخوارزمي الهندسية المجلدخديجة نجاح زيدان 24 - 1,3,4-فلوروفينيل( -دراسة تثبيط التآكل لمركبات قواعد اآلزو شيف المحضرة من )ب ياديازول لسبيكة الفوالذ الكربوني في الوسط الحمضيث خديجة نجاح زيدان1*, احمد وحيد ناصر2 التكنلوجية، بغداد، العراق هندسة كيمياوي، الجامعة قسم هندسة تكرير النفط وتكنلوجيا الغاز، 1 العراق بغداد، بغداد، جامعة الهندسة،كلية الكيمياوية، قسم الهندسة 2 khadija89najahz@gmail.comالبريد االلكتروني: * لمستخلص ا شيف بطرق مختلفة، وثمت دراسة قواعدها كمثبطات التآكل لسبائك الفوالذ الكربوني في حامض الهيدروكلوريك بتركيز -تحضير لمركبات قواعد آزوالتم رت المركبات الجديدة باستخدام . كلفن في الوسط الحامضي 298موالري عند درجة حرارة 0.1 ثياديازول، وطرق طيفية -4، 3، 1-(فلوروفينيل-بارا)ُحض ِّ فة مدى فعالية مثل تحويل فورييه لألشعة تحت الحمراء والرنين المغناطيسي النووي لتحديد هوية المركبات، ومنحنيات االستقطاب الجهدي الديناميكي لمعر التآكل بارا. تثبيط مع -يتفاعل ( أمينوفينيل-4)-N '-(1لتحضير ( A1) أسيتوهيدرازيد ( يل-2-ثياديازول-3،4، 1-(فلوروفينيل-4)-5)-2أمينوأسيتوفينون من أمالح الديازونيوم الُمحضرة مع ( A3-A6)شيف -ُصنعت قواعد آزو(. A2)أسيتوهيدرازيد ( يل-2-ثياديازول-3،4، 1-(فلوروفينيل-4)-5)-2-(إيثيليدين لت تركيبات هذه المركبات لتحسين قدرتها على منع التآكل في مجموعة من البيئات الصناعية، وخاصةً للمعادن المعرضة للبيئات الحمض. فينوالت مختلفة ِّ . ية ُحو ويُعزى تحسن نشاط المثبط إلى تكوين .أعلى قيمة( A6)، حقق الدواء االصطناعي %90عند . %90و %76بين %( IE)تراوح نطاق نسبة الكفاءة المثبطة ة جدًا لالستخدام كمثبطات تآكل الفوالذ الكربوني في البيئات شيف االصطناعية واعد -تشير هذه النتائج إلى أن قواعد آزو. طبقات امتزاز واقية على سطح الفوالذ . وقد تستفيد التطبيقات في القطاعات التي تُعد فيها مقاومة التآكل أمًرا بالغ األهمية من هذه المعرفة. الحمضية اآلزو قاعدة مركبات تصنيع تم البحث هذا من-في حرارة واستخدمت 1,3,4-thiadiasols- (p-fluorophenyl) شيف درجة في 298عند كلفن سبيكة الفوالذ الكربوني. تمت دراسة تآكل الفوالذ الكربوني في الظروف الحامضية باستخدام منحنى االستقطاب لتآكل موالري كمثبطات 0.1الهايدروكلوريك - ثياديازول-1,3,4فلوروفينيل( أسيتوهيدرازيد )-4)-5)-2-أمينو فينيل( إيثيليدين1-(4-))-'N ليشكل (A1) أمينو أسيتوفينون والمركب-الديناميكي. يتكثف بارا وخضعت هذه المواد لتعديالت (A3-A6) خضعت أمالح الديازونيوم المحضرة والفينوالت المختلفة لعملية اقتران لتكوين قواعد آزو شيف (A2) (ييل-2 نسبة كفاءة التثبيط هيكلية لتحسين كفاءتها كمثبطات للتآكل في مجموعة من البيئات الصناعية، خاصة بالنسبة للمعادن المعرضة للتآكل. أشارت النتائج إلى أن (IE%) وكانت المادة الكيميائية%90إلى %76تراوحت بين ، (A6) على السطح الفوالذي، وتكونت طبقات امتصاص وقائية %90هي األعلى قيمة وهي .وهي المسؤولة ألداء المانع الجيد mailto:khadija89najahz@gmail.com