【作者】 黄元波；

【导师】 顾继友；

【作者基本信息】 东北林业大学 ， 生物材料工程， 2016， 博士

【摘要】 随着社会发展对石油类不可再生资源的需求日益增多,各国为了缓解能源压力和满足环保要求,逐渐重视可再生资源化学利用方面的研究。植物油作为一种重要的可再生资源,由其制备的多种化工产品已进入市场,但目前所采用的植物油多为大豆油(soybean oil,简称SBO)、菜籽油等食用油,存在与人类争粮争地问题。橡胶籽油(rubber seed oil,简称RSO)作为一种重要的植物油资源,不仅不可食用,而且作为橡胶产业的副产物,完全不存在上述问题。目前,环氧化法制备环氧植物油及其羟基化制备植物油基多元醇是制备植物油基化学品的重要途径之一,但是,目前环氧化过程主要采用硫酸等腐蚀性较强的无机酸为催化剂,不仅易腐蚀生产设备、污染环境,而且与产物难以分离,使产物的后处理工艺变得复杂。因此,本文以非食用的木本油料RSO为原料,在其环氧化反应中创新地引入Ti-MCM-41介孔分子筛为催化剂来制备环氧橡胶籽油(epoxidized rubber seed oil,简称ERSO),并由其进一步制备橡胶籽油基多元醇(rubber seed oil based polyol,简称RSO-polyol)。(1)对原料RSO进行了基本理化特性分析,采用GC-MS、FTIR、1H NMR,13C NMR、DSC、TG等仪器分析手段进行了表征,并在此基础上对比了RSO和SBO的脂肪酸组成与含量,结果表明RSO的脂肪酸组成与SBO相似,RSO的不饱和脂肪酸含量为86.09%,理论环氧值为7.98%,可以做为制备E RSO及RSO-polyol的上好原料。(2)采用浸渍法制备了Ti-MCM-41介孔分子筛催化剂,以油酸甲酯为反应模型物,确定了适用于植物油环氧化反应的Ti-MCM-41介孔分子筛催化剂的最佳制各条件。并对其循环使用和再生活化性能进行了测试,结果表明,经三次循环使用和再生活化后,Ti-MCM-41介孔分子筛催化剂仍具有良好的催化性能,所制备的环氧油酸甲酯的环氧值仍在5%以上。对Ti-MCM-41介孔分子筛催化剂进行FTIR、XRD (?) BET、 EDAX分析的结果表明,负载Ti后的MCM-41介孔分子筛催化剂的长程有序性有所破坏,比表面积减少,孔容下降,孔径几乎未变；TEM分析结果表明,Ti-MCM-41介孔分子筛催化剂的孔道为规则排列的六方结构,一维平行分布,孔道和骨架为交替结构。(3)以上述绿色、非均相的Ti-MCM-41介孔分子筛为催化剂,在催化油酸甲酯环氧化的基础上,研究了RSO的环氧化反应,确定了最佳环氧化反应的工艺条件。结果表明,ERSO的环氧值随着反应时间、反应温度和催化剂用量的增加而先升高后降低,随着环氧化剂叔丁基过氧化氢用量的增加而降低。RSO环氧化最佳工艺条件为：反应时间为5h,反应温度为70℃,叔丁基过氧化氢与RSO的摩尔比为4：1,Ti与RSO摩尔比为0.05：1。在此条件所制得ERSO的碘值为11.7g/100g,环氧值为5.6%,平均分子量约为929.93g/mol,双键转化率为90%,相对环氧转化率为80.9%。此ERSO的环氧值比HG/T 4386-2012行业标准中的环氧大豆油(epoxidized soybean oil,简称ESBO)标准要求略低,碘值略高,其它性能相似。GC-MS、FTIR和NMR分析结果表明,ERSO中环氧产物的含量约为70.39%,但仍有小部分双键未能发生环氧化反应和发生了开环副反应,生成了少量的羟基化合物；DSC分析结果表明,RSO环氧化后,结构趋向均匀,耐低温性能优于RSO;TG分析结果表明,ERSO的热解分为2个阶段,总失重率达到99.58%,ERSO的热稳定性低于RSO。(4)采用尿素包埋法分离出RSO中的多不饱和脂肪酸,以硫酸为催化剂,过氧化氢为氧源,确定了环氧多不饱和脂肪酸的最佳制备工艺条件。结果表明,环氧多不饱和脂肪酸的环氧值随着过氧化氢用量、冰乙酸用量、反应时间、反应温度的增加而先升高后降低。环氧多不饱和脂肪酸的最佳制备工艺条件为：多不饱和脂肪酸与过氧化氢质量比为1：2.5,多不饱和脂肪酸与冰乙酸质量比为1：0.9,反应时间为3h,反应温度为65℃,在此条件下制得的环氧多不饱和脂肪酸的碘值为5.32 g/100g,酸值为197.5mgKOH/g,环氧值为8.28%,环氧值低于理论环氧值。环氧多不饱和脂肪酸的FTIR分析结果表明,多不饱和脂肪酸在硫酸催化作用下发生了环氧化反应,生成了环氧基团,同时,环氧化反应过程中部分双键发生了开环副反应。因分离纯化多不饱和脂肪酸的得率仅约为38%-45%,所以在后续的研究中不采用环氧多不饱和脂肪酸进行研究,确定采用Ti-MCM-41介孔分子筛催化制备的ERSO进行羟基化反应,制备RSO-polyol。(5)以氟硼酸为催化剂,甲醇与异丙醇为羟基化试剂,以ERSO为原料,研究了ERSO的羟基化反应,确定了RSO-polyol的最佳制备工艺条件。结果表明,RSO-polyol的羟值随着反应时间、反应温度、醇总用量和催化剂用量、甲醇和异丙醇质量比的增加而先升高后降低。RSO-polyol最佳制备工艺条件为：反应时间30min,反应温度70℃℃,ERSO与醇总用量的质量比为1：4,催化剂氟硼酸与ERSO质量比为1：100,甲醇与异丙醇质量比为1：3。在此条件下制备的RSO-polyol的酸值为2.75mgKOH/g,羟傻为348.2 mgKOH/g,平均分子量为991.82g/mol,水份含量为0.093%,粘度为5634mPa·S。 RSO-polyol 的 FTIR、NMR分析结果表明,ERSO经羟基化反应时,其环氧基团发生了开环反应,并生成了具有羟基的化合物；DSC分析结果表明,RSO-polyol的耐低温性能优于RSO和ERSO;TG分析结果表明,RSO-polyol的热解过程分为3个阶段,总失重率约为81.32%,RSO-polyol的热稳定性低于RSO和ERSO。(6)考察了RSO-polyol替代量对聚氨酯泡沫材料性能的影响。结果表明,当RSO-polyol替代量≤20%时,所制备的橡胶籽油基聚氨酯(rubber seed oil based polyurethane,简称RSO-PU)泡沫材料的表观密度和压缩强度均达到冰箱、冰柜用硬质聚氨酯泡沫塑料的国家标准1I类要求;FTIR分析结果表明,RSO-polyol替代丙三醇确实可合成出聚氨酯泡沫材料：TG分析结果表明,RSO-PU泡沫材料有4个热失重阶段,随着RSO-polyol替代量的增加,RSO-PU泡沫材料的热稳定性得到提高；SEM分析结果表明,在RSO-polyol替代量较少时,匀泡作用起到主要作用,所制备的RSO-PU泡沫材料的泡沫均匀、规整、细致,力学性能优良；当RSO-polyol替代量增大时,对泡孔大小、材料性能起主要作用的是增塑作用,所制备的RSO-PU泡沫材料的泡沫大而不均,且泡沫力学性能下降。以上研究结果表明,Ti-MCM-41介孔分子筛催化剂可用于植物油环氧反应中,制得的ERSO满足要求,且可进一步合成RSO-polyol; RSO-polyol成功地应用于聚氨酯泡沫材料中,并获得了物理力学性能良好、热稳定性较高的RSO-PU泡沫材料,实现了可再生橡胶籽油资源制备成化工产品替代石油类化工产品的目的。更多还原

【Abstract】 With the development of the whole society, demands for the petroleum-based non-renewable resources increase day by day. In order to relieve the shortage of energy and meet environmental concerns, researchers have gradually paid more attentions to the chemical utilization of renewable resources. Vegetable oil, as an important renewable resource, has been used in many fields. A variety of chemical products prepared from vegetable oil had emerged into the market, although most of them were prepared from edible oils such as soybean oil (SBO), rapeseed oil, which had problems that fighting for food with human and fighting for fields with grain. Rubber seed oil (RSO) which obtained from rubber seed is one of the important vegetable oil. The utilization of rubber seed oil can avoid the above problems because it is inedible and by-product of rubber tree. At present, vegetable oil-based chemicals can be obtained by epoxidation for epoxy products and hydroxylation for polyols. However, some strong corrosion inorganic acids, such as sulfuric acid, were generally used as catalyst in the epoxidation process of vegetable oils. And these catalysts not only eroded equipment and pollute the environment, but also were difficult to be separated completely from products, which made the product post-treatment technology complex. In this paper, by using RSO as the raw material, a novel mesoporous molecular sieve Ti-MCM-41 was used as catalyst in the epoxidation process of RSO for production of epoxidized RSO (ERSO). And rubber seed oil based polyol (RSO-polyol) were prepared from the ERSO by hydroxylation method. All the processes could meet the demands for green, environment friendly.(1) The properties of RSO were tested and characterized by GC-MS (Gas Chromatography-Mass Spectrometry), FTIR (Fourier Translation Infrared Spectrum),*H MR(Nuclear Magnetic Resonance Spectrometry),13C NMR, DSC (Differential Scanning Calorimetry), TG (Thermogravimetric Analysis), etc. The fatty acid compositions and content of RSO had been compared with SBO. It was found that the fatty acid compositions of RSO with unsaturated fatty acid of 86.09% were similar to SBO. And the theoretical epoxy value of RSO could be up to 7.98%, which meant that the RSO could be a good raw material for preparing ERSO and RSO-polyol.(2) The mesoporous molecular sieve Ti-MCM-41 was prepared by dipping method. The optimum preparation conditions for the Ti-MCM-41 catalyst were obtained from epoxidation of oleic acid methyl ester. And the recyclability and regenerability of the catalyst were also tested. Results showed that the Ti-MCM-41 catalyst had a good catalytic performance in the epoxidation after thrice recycle and regeneration, which the epoxy value of epoxided oleic acid methyl ester was still more than 5%. FTIR、X-Ray Diffraction (XRD), N2Adsorption-Desorption Isotherms (BET) and Energy Dispersive X-Ray (EDAX) were employed to characterize Ti-MCM-41 catalyst. Results showed that with the increasing of the loading amount of Ti, the long-range order of MCM-41 was destroyed, while the specific surface area and pore volume were decreased, pore size was almost unchanged. Moreover, results of Transmission Electron Microscopy (TEM) analysis showed that the Ti-MCM-41 catalyst exhibited regular arrangements of the six party structure and parallel distribution with one-dimension. The pore and the skeleton was the alternate structure.(3) Epoxidation of RSO was carried out using the above green and heterogeneous Ti-MCM-41 as catalyst and the optimal conditions were obtained. It was found that with the increase of reaction time, reaction temperature and amount of catalyst, the epoxy value of ERSO increased firstly, then decreased. The optimal conditions for preparation of ERSO were reaction time of 5h, reaction temperature of 70℃, tert butyl hydrogen peroxide/RSO mole ratio of 4：1, titanium/RSO mole ratio of 0.05:1. Under this optimal conditions, ERSO could be obtained with the iodine value of 11.7g/100g, the epoxy value of 5.6%, average molecular weight of 929.93 g/mol, the conversion of double bond of 90%, and the relative epoxidation conversion of 80.9%. Compare with epoxidized soybean oil (ESBO) according to HG/T 4386-2012 industry standards, ERSO had the similar properties, while the epoxy value of ERSO was slightly lower and the iodine value was slightly higher. The GC-MS, FTIR and NMR analysis results of ERSO showed that epoxy group was formed after epoxidation reaction and its content in ERSO was around 70.39%. But it was also found that there still remained a small number of double bond and hydroxyl compounds in the ERSO. The DSC analysis results showed that the ERSO had a good low-temperature-resistance, which was better than RSO. The TG analysis results showed that there were two stages during the pyrolysis of ERSO, and the total weight loss could be up to 99.58%. However, the thermal stability of ERSO was lower than that of RSO.(4) Polyunsaturated fatty acids (PUFA) from RSO were obtained by using the method of urea complex fractionation. The optimum conditions for preparing the epoxy polyunsaturated fatty acids (EPUFA) were studied by using sulfuric acid as the catalyst and hydrogen peroxide as the oxygen source. The results showed that the epoxy value of EPUFA increased firstly and then decreased with the increase of hydrogen peroxide dosage, glacial acetic acid dosage, reaction time and reaction temperature. The optimum conditions for preparing EPUFA were: PUFA/hydrogen peroxide mass ratio of 1:2.5, PUFA/glacial acetic acid mass ratio of 1:0.9, the reaction time of 3h and reaction temperature of 65℃. Under this optimum conditions, the EPUFA could be obtained with the iodine value of 5.32 g/100g, acid value of 197.5 mgKOH/g, epoxy value of 8.28%. Even though the epoxy value of EPUFA was lower than the theoretical one. The FTIR analysis of PUFA showed that the epoxy groups were formed during the epoxidation of PUFA using sulfuric acid as the catalyst. But ring-opening reaction was happened at the same time. Due to the low yield of the polyunsaturated fatty acids with 38%-45%, EPUFA could not be used as the raw material for the preparation of polyols. So the ERSO catalyzed by Ti-MCM-41 was used to prepare RSO-polyol.(5) The hydroxylation reaction of ERSO was studied using fluorine boric acid as catalyst, methanol and isopropanol as the hydroxyl reagent. The optimum conditions for preparing RSO-polyol were obtained. The results showed that the hydroxyl value of RSO-polyol increased firstly then decreased with the reaction time, reaction temperature, the total amount of alcohols, the amount of catalyst, the mass ratio of methanol and isopropanol. The optimum preparation conditions were as follows:the reaction time of 30min, the reaction temperature of 70, the mass ratio of ERSO and the total amount of alcohols of 1:4, the mass ratio of fluorine boric acid/ERSO of 1:100, and the mass ratio of methanol/isopropanol was 1:3. Under the optimum conditions, the RSO-polyol could be obtained with acid value of 2.75 mgKOH/g, hydroxyl value of 348.2 mgKOH/g, average molecular weight of 991.82g/mol, moisture content of 0.093%, and the viscosity of 5634 mPa-s. FTIR and NMR analysis results showed that the epoxy group in ERSO had a ring-opening reaction to form hydroxyl compound. The DSC analysis showed that the low-temperature-resistance of RSO-polyol was better than that of RSO and ERSO. The TG analysis showed that there were three stages during the pyrolysis of RSO-polyol, and the total weight loss could be up to 81.32%. And the thermal stability of RSO-polyol was lower than that of RSO and ERSO.(6) The influences of RSO-polyol substitution amount on the properties of polyurethane (PU) foams were studied. The results showed that when the substitution amounts of RSO-polyol was less 20%, the apparent density and compressive strength of RSO-based PU (RSO-PU) foams could meet the requirements of Chinese national standard Ⅱ for rigid PU foams in applications of refrigerators and freezers. The FTIR analysis results showed that RSO-PU foams were prepared successfully with the substitution of glycerol by RSO-polyol. The TG analysis results showed that there are four stages during the pyrolysis of RSO-PU foams. The thermal stability of RSO-PU foams had been improved with the increasing of RSO-polyol substitution amounts. The SEM analysis results showed that when the substitution amounts of RSO-polyol were low, foaming was the main effect factor that made the foams with evenly, regular, meticulous structure, and excellent mechanical properties. With the increasing of the substitution amounts of RSO-polyol, plasticizing was the main effect factor that made the foams with big and non-homogeneous structure, and mechanical properties of the foams were decreased.The above results demonstrated that the mesoporous molecular sieves Ti-MCM-41 catalyst could be used in the epoxidation reaction of RSO to prepare ERSO which could further be use in the synthesis of RSO-polyol. Moreover, RSO-polyol was applied to prepare PU foams which had favorable mechanical and physical properties, and higher thermal stability. It could be achieved the aim of chemical products from renewable rubber seed oil resources to take the replace of petroleum chemical products.更多还原