N Hattawi Salam, G Ahmed Ahmed, M Fadhil Firas, R Kuot Stephen, S Alsubaie Mai, L Alazmi Mohammed, Fetouh H A
Northern Technical University, College of Health and Medical Techniquies, Department of Renal Diaylsis Techniquies, Kirkuk, Iraq.
University of Kirkuk, College of Education for Pure Science-chemistry Department, Kirkuk, Iraq.
Heliyon. 2024 Jun 27;10(13):e33743. doi: 10.1016/j.heliyon.2024.e33743. eCollection 2024 Jul 15.
The novelty of this study is that it the first time blending and formulation of chitosan as a new hybrid (organometallic) protective coatings for achieving synergistic protection for carbon steel alloy during acid pickling. The role of coated silica (by 0.1 wt % stearic acid lubricant) in the improvement of coating performance was highlighted. Variable weight percentage of chitosan and silica in addition to a fixed weight percentage (35 %) of guar gum natural plant resin, 5 × 10 mmol (2-Hydrazinyl-6-methyl (or phenyl) -4, 5-di-H pyrimidinone) as organic corrosion inhibitors were compounding as hot melt in the presence of a low cost surfactant as an emulsifying agent improved compatibility between coating constituents. Guar gum increased coating flow during application and grafted chitosan into high molecular copolymer resin insoluble in acid media. Phosphorous acid improved coating flexibility during application by hot dipping. Hybrid coating decreased corrosion potential of carbon steel and retarded both redox reactions of corrosion acting as adsorbed mixed-type inhibitor. Percentages protection (%P) approached hundred percentage as confirmed from the agreement between impedance and polarization parameters. Guar gum plant resin and slice powder increased gloss of coating. The coated silica filled the pores and increased stiffness of coating. Super hydrophobicity of coating was confirmed by the measured contact angle above 150C indicating good spreading of coating sample as insulating adherent surface film.
本研究的新颖之处在于首次将壳聚糖混合并配制成一种新型杂化（有机金属）保护涂层，用于在酸洗过程中对碳钢合金实现协同保护。强调了涂覆二氧化硅（添加0.1 wt%硬脂酸润滑剂）在改善涂层性能方面的作用。除了35%固定重量百分比的瓜尔胶天然植物树脂外，壳聚糖和二氧化硅的可变重量百分比，以及5×10 mmol（2-肼基-6-甲基（或苯基）-4,5-二氢嘧啶酮）作为有机腐蚀抑制剂，在一种低成本表面活性剂作为乳化剂的存在下热熔融混合，提高了涂层成分之间的相容性。瓜尔胶在涂覆过程中增加了涂层的流动性，并将壳聚糖接枝到不溶于酸性介质的高分子共聚物树脂中。亚磷酸通过热浸法在涂覆过程中提高了涂层的柔韧性。杂化涂层降低了碳钢的腐蚀电位，并延缓了作为吸附混合型抑制剂的腐蚀的氧化还原反应。从阻抗和极化参数之间的一致性可以确认，保护百分比（%P）接近100%。瓜尔胶植物树脂和片状粉末增加了涂层的光泽度。涂覆的二氧化硅填充了孔隙并增加了涂层的硬度。通过测量接触角高于150°C证实了涂层的超疏水性，表明涂层样品作为绝缘粘附表面膜具有良好的铺展性。
