【作者】 孟冬梅；

【导师】 刘俊康；

【作者基本信息】 江南大学 ， 应用化学， 2012， 硕士

【摘要】 油酸Estolides酯具有优良的低温性能和润滑性能,有广泛的工业应用前景,引起了国内外学者的广泛关注。美国农业研究所已进行多年的研究,取得了很大的成就,但仍存在原料成本高、反应时间长和转化率低等缺点,且以棕榈油酸为原料合成Estolides酯尚未见报道。为克服这些不足,采用棕榈油酸、月桂酸、异辛醇等原料,选用高氯酸为催化剂,对该模型反应工艺做了进一步的探索,在不同条件下合成了棕榈油酸交内酯Estolides,并将微波运用于此合成,建立了一种新的制备方法,对合成条件进行了优化,继而将聚合产物Estolides与异辛醇进一步酯化得到一系列适合做润滑油的酯类基础油棕榈油酸Estolides酯,且对它们的理化性能进行了分析,探讨潜在的应用前景。以棕榈油酸在真空条件下的缩合反应为模型,通过单因素试验考察了反应温度、反应时间、催化剂用量等因素对油酸缩合反应的影响规律,并得出最佳反应条件为:温度:70℃,时间:24h,催化剂HClO4用量为油酸量的5%(摩尔比),此条件下酸值的变化值为80.5mg/g。产物主要为二聚物,缩合反应的转化率高达75.9%。棕榈油酸与月桂酸的缩合反应中,得出油酸与月桂酸用量的摩尔比不宜低于2︰1。进行大量的缩合反应,并将缩合产物进行分子蒸馏,对提纯后的缩合产物进行红外光谱和气相色谱等分析,并测定了理化性能。采用微波加热的方法进行了油酸缩合反应实验,分别通过单因素试验和正交试验探讨了反应温度、反应时间、催化剂用量、微波功率等反应条件对油酸交内酯Estolides合成的影响。实验采用两台不同型号的微波炉并进行了对比,MCR-3微电脑微波化学反应器的性能优于HWL07-3型实验微波炉,反应效果也较好,得到的的较佳条件为:微波功率320W,反应温度60℃,催化剂用量10%(摩尔比),反应时间4h,转化率高达77.7%。分别采用一步法和两步法合成了棕榈油酸Estolides酯,对两步法中酯化反应的催化剂进行了筛选,高氯酸为催化剂时得到最高酯化率。得出反应随时间变化的曲线及酸醇不同投料比时的转化率。最佳条件为:反应时间,4h;酸醇摩尔比,1︰1.2。棕榈油酸Estolides与异辛醇的酯化率为96.8 %。对产物棕榈油酸Estolides异辛酯进行了分子蒸馏提纯,并通过红外光谱和电喷雾质谱对反应产物进行分析,得出聚合物的组成以二聚棕榈油酸Estolides异辛酯为主。对棕榈油酸Estolides异辛酯的性能进行了测试,倾点-29℃,运动粘度100℃时17.15 mm2/s,40℃时114 mm2/s,粘度指数165,闪点高于300,适合做润滑油。更多还原

【Abstract】 Oleic acid estolide esters are of good low temperature and lubricating properties and have hence wide industry applications. It has caused researchers’wide attention at home and abroad. The problems of high cost for row materials, long reaction time and low conversion are existed, though famous scholars from USDA researched many years ago and achieved great progress. There was no report on estolides esters that synthesized by palm-oleic acid. So model reaction process was explored further, synthesis of Palm-oleic estolides catalyzed by perchloric acid under different conditions, and Palm-Oleic acid, lauric acid, decylic acid, 2-ethylhexyl alcohol are used as the raw material in this experiment. Microwave was used to this reaction as a new preparation method. The products of condensation were esterified with 2-ethylhexyl alcohol to get a series of Palm-oleic estolides esters with good lubricating property. Their properties were analyzed.During one factor tests, the condensation reaction of Palm-Oleic acid at vacuum condition was used as model reaction to investigate influence law of reaction temperature, reaction time and dosage of catalyst on the condensation reaction of Palm-oleic acid. The optimum reaction conditions were found to be: 70℃of reaction temperature, 24h of reaction time, and 10% of the molar ratio of HClO4 and oleic acid. Under optimized reaction conditions, 80.5 mg/g acid value change was obtained. The products were mainly dimerization, the best conversion rate under this condition is 75.9 %. Condensation of Oleic acid and lauric acid can gain better rate when material compounding ratio is over 2︰1. Condensation products were purfied by molecular distillation, and analyzed by IR spectrum and gas chromatography. Physics and chemistry performances were gained.For microwave assisted synthesis of oleic estolides, we examined effect of reaction time, reaction temperature, catalyst dosage and Microwave power did on the condensation reaction of oleic acid. The experiments used two kinds of microwave oven with different types, and make a comparison. MCR-3 microwave chemical reactor was better than HWL07-3. The prefer conditions of MCR-3 microwave chemical reactor: power 320W, reaction temperature: 60℃, the molar ratio of HClO4 and oleic acid is 10%, 4 hour of heating by microwave, reaction rate 77.7%.Palm-oleic estolides esters were synthesis by one step and two steps separately. Catalysts were selected in the two steps reaction. Best conversion was received when used HClO4 as catalyst. The curve of reaction time and conversion rate of different molar ratio of acid to alcohol were gained. The optimum reaction conditions: reaction time: 4h, the molar ratio of acid to alcohol was 1:1.2, and the ester rate is 96.8%.The products of Palm-oleic estolides ethylhexyl esters were refined by molecular distillation, MS and IR were used to analyse the basic structure of reaction products. The products system was mainly make up of dimerization Palm-oleic estolides esters. The functions were measured and come to a conclusion that pour point were 29℃below zero, dynamic viscosity 17.15 mm2/s (100℃) and 114 mm2/s (40℃), flash point over 300, viscosity exponent 165, all of this determines that they are suitable for lubricating oil.更多还原