【正文】 pm）的 合成的兩親分子 作為鋁（ 3SR）的緩蝕劑在酸性介質(zhì)（ 4N HCl）中的緩蝕效果。他們的方案也計(jì)算了吸附熱力學(xué)和這些兩親分子膠束化過程。 關(guān)鍵詞：非離子表面活性劑 希夫堿 吸附 表面張力 緩蝕 緩蝕速率 緩蝕效率 a b s t r a c t A novel series of selfassembled nonionic Schiff base amphiphiles was synthesized and their chemical structures were confirmed using elemental analysis, FTIR spectroscopy and 1H NMR spectra. The surface activities of these amphiphiles were determined based on the data of surface and interfacial tension, critical micelle concentration, effectiveness, efficiency, maximum surface excess and minimum surface area. Thermodynamics of adsorption and micellization processes of these amphiphiles in their solutions were also calculated. The surface and thermodynamic data showed their higher tendency towards adsorption at the interfaces. The synthesized amphiphiles were evaluated as corrosion inhibitors for aluminum (3SR) at different doses (400– 10 ppm) in acidic medium (4N HCl) using weight loss and hydrogen evolution techniques. The corrosion measurements showed that the synthesized nonionic Schiff bases could serve as effective corrosion inhibitors. The surface and corrosion inhibition activities were correlated to the chemical structures of the inhibitors. 摘要 一種新型系列自組裝非離子型兩親 Schiff堿被合成，它們的化學(xué)結(jié)構(gòu)用元素分析法確定，紅外光譜和核磁共振氫譜。這些兩親分子的表面活性的確定要基于表面張力和界面張力、臨界膠束濃度，效果，效率，最大和最小表面積的數(shù)據(jù)。表面 狀況數(shù)據(jù) 和熱力學(xué)數(shù)據(jù)顯示它們對在界面吸附有較大的傾向 。 腐蝕實(shí)驗(yàn)表明合成的非離子型席夫堿是有效的緩蝕劑 。 1. Introduction Ferrous, nonferrous metals and their alloys are extensively used in industry. To remove unwanted scale and salt deposits or mill scales formed during manufacture, metals are immersed in acid solutions, which are known as an acid pickling bath. After the scale is removed, the metal may be subjected to attack by the acids. In order to reduce the degree of metal attack and rate of consumption of the acid, corrosion inhibitors are added to the pickling solutions Hydrochloric and sulphuric acids are the most monly used acids in the pickling bath [1,2]. Most mercial inhibitor formulations include aldehydes and amines in their structure [3,4]. The choice of the inhibitors is based on two considerations: first, they could be synthesized conventionally from relatively cheap raw materials。 要除去金屬在生產(chǎn)過程中形成的未知污垢和鹽垢或 銑 垢，金屬要浸泡在酸液中，也就是我們常說的 酸洗浴 。為了降低金屬受腐蝕的程度和酸液的消耗速率，我們需要在酸洗液中添加緩蝕劑。選擇緩蝕劑要考慮的兩個(gè)因素是：一 ，它 們能夠很方便的由相關(guān)原料合成；二， 它們含有帶電子的苯環(huán)或者是有電負(fù)性原子，如含有芳香環(huán)的席夫堿 [5,6]。 這些物質(zhì)通常 能 有效地吸附在金屬表面。自組裝單層膜是緩蝕的一種便捷方法，膜的 化學(xué)組成和自組裝單分子膜的厚度可 通過 設(shè)計(jì)吸附劑的合成 實(shí)現(xiàn)。 實(shí)驗(yàn)結(jié)果發(fā)現(xiàn)， 結(jié)果發(fā)現(xiàn)， 含有雜原子化合物 的致密 自組裝單層 能 有效阻止某些電化學(xué)過程，從而 能夠作為有效的緩蝕 劑 。 表征 這些化合物對鋁合金緩蝕效率分別采用失重 法 和析氫的技術(shù)。 2. Experimental procedures . Synthesis of Schiff bases mol of anisaldehyde was condensed with mol of paminobenzoic acid in the presence of 250 mL of ethyl alcohol as a solvent. The reaction mixture was refluxed for 6 h and then left overnight until the product was precipitated. The product was washed by petroleum ether and recrystallized from ethanol. The final product was dried under vacuum at 40 ?C [15]. The produced Schiff base was denoted as SB and the chemical structure was represented in Scheme 1. Scheme 1. Chemical structure of the synthesized Schiff base. Scheme 2. Chemical structure of the synthesized nonionic Schiff base. 茴香醛 和 250mL的無水乙醇做溶劑。用石油醚洗滌，再用乙醇重結(jié)晶。合成的席夫堿記為 SB，化學(xué)結(jié)構(gòu)式 如 方案 1表示。 16: hexadecanoate 8: octadecanoate and/or oleate) were esterified by the synthesized Schiff base SB in equimolar ratio in xylene as a solvent and ptoluene sulfonic acid (.%) as a dehydrating agent [16]. The reaction was continued until plete removal of the water of the reaction. Vacuum distillation was performed to remove the unreacted materials and the solvent, Scheme 2. The produced nonionic Schiff bases were denoted as SBPEGalkanoate (R) and listed in Table 1. . 非離子型兩性席夫堿的合成 等摩爾比的不同分子量的聚乙二醇（ 400,1000,2020和 /或 3000 ， n= /或 68）和不同鏈長的單鏈烷烴（ R=10：癸酸； 16；棕櫚酸； 18：硬脂酸和 /或油酸）縮合的聚乙二醇酯與已合成的席夫堿在以二甲苯為溶劑，對甲苯磺酸（ .%）做 干燥劑 [16] 的條件下進(jìn)行酯化反應(yīng)。真空蒸餾除去未反應(yīng)的物料和溶劑，方案 2 .記非離子型席夫堿產(chǎn)物為 SBPEG鏈烷酸（ R），列在表 1中。結(jié)果列在表 1中。此外，界面張力測量在緩蝕劑 油的體系中進(jìn)行 [17]。 4N HCl 溶液在 25?C 下加入不同濃度范圍 (400– 10 ppm)的緩蝕劑。測試的樣品用蒸餾水和乙醇洗滌后，干燥，稱重。緩蝕劑效率百分比的計(jì)算方式 [18]： 緩蝕效率 %=[Wb ?W / Wb] 式中， Wb 和 W分別代表鋁片樣本在有緩蝕劑和沒緩蝕劑時(shí)的重量損失。 . Hydrogen gas evolution technique In the gas evolution measurement, the corrosion rates of aluminum were investigated by the hydrogen evolution rate with the inhibitors concentrations of 400, 200, 100, 50, 25 and 10ppm and 4N HCl solution without inhibitors. The hydrogen evolved is a function of the corrosion reaction and it displaced the fluid in the gasometeric setup, which is read directly. Experiments performed without inhibitors recorded the highest volume of hydrogen gas evolved [19]. The percentage efficiency was calculated as %Efficiency =[Vb ? V / Vb ] where Vb and V are the volumes of hydrogen evolved without and with inhibitors, respectively. . 析氫技術(shù) 在氣體 析出 實(shí)驗(yàn)測試中， 用氣體的變化速率考察鋁在含加有濃度為 400,200,100,50,25 和 10 ppm緩蝕劑以及沒加緩蝕劑的 4N HCl溶液中的腐蝕速率。 實(shí)驗(yàn)表明 沒有加緩蝕劑 的 氫氣析出