Preparation of magnesium borate succinimide and its characteristics as a lubricating oil additive

Succinimide has for a long time been widely used for ashless dispersants in engine lubricating oils. However, this kind of dis‐persant does not have particularly good antioxidant, antifriction, antiwear or acid neutralisation properties. In this paper, a method is suggested for modifying succinimide so as to obtain improved antioxidant, acid neutralisation, antifriction, and antiwear properties. Magnesium borate cannot be dissolved in mineral lubricating oil. In the presence of succinimide, however, it will exist in a lubricating oil in the form of a colloid or complex. Therefore, in the present work, magnesium oxide, boric acid, and water were mixed together with succinimide. In the reaction process, some of the magnesium borate formed in situ will be surrounded by succinimide, forming stable colloids; the remainder will react with the succinimide, forming well distributed complexes in the lubricating oil. The presence of water is very important for this process. At least four moles of water are needed for one mole of magnesium borate. The resulting material has been evaluated as a lubricating oil additive. The experiments have shown that this kind of material possesses good antioxidant, acid neutralisation, antifriction, and antiwear properties, apparently due to the introduction of magnesium borate. The introduction of the magnesium borate does not influence the good dispersant properties of the succinimide.     

Acetic Acid Can Catalyze Succinimide Formation from Aspartic Acid Residues by a Concerted Bond Reorganization Mechanism: A Computational Study

Succinimide formation from aspartic acid (Asp) residues is a concern in the formulation of protein drugs. Based on density functional theory calculations using Ace-Asp-Nme (Ace = acetyl, Nme = NHMe) as a model compound, we propose the possibility that acetic acid (AA), which is often used in protein drug formulation for mildly acidic buffer solutions, catalyzes the succinimide formation from Asp residues by acting as a proton-transfer mediator. The proposed mechanism comprises two steps: cyclization (intramolecular addition) to form a gem-diol tetrahedral intermediate and dehydration of the intermediate. Both steps are catalyzed by an AA molecule, and the first step was predicted to be rate-determining. The cyclization results from a bond formation between the amide nitrogen on the C-terminal side and the side-chain carboxyl carbon, which is part of an extensive bond reorganization (formation and breaking of single bonds and the interchange of single and double bonds) occurring concertedly in a cyclic structure formed by the amide NH bond, the AA molecule and the side-chain C=O group and involving a double proton transfer. The second step also involves an AA-mediated bond reorganization. Carboxylic acids other than AA are also expected to catalyze the succinimide formation by a similar mechanism.     

一种简便的丁二酰亚胺的合成方法

以亚磷酸为催化剂对由丁二酸和氨水合成丁二酰亚胺的工艺进行了探讨 ,实验结果表明 ,反应物的摩尔比为 1∶ 1 .1 ,反应温度初期为 70°C,然后在 1 2 0°C保温 1 h;环合反应温度为 1 95°C,然后在此条件下保温 5 h是较好的工艺参数 ;能获得高产率的丁二酰亚胺。此工艺已在工厂进行了2 0 0 kg级的实际生产 ,结果良好     

DMH对丁二酰亚胺无氰镀银的影响

将5,5-二甲基乙内酰脲(DMH)加入丁二酰亚胺镀银溶液中,考察了DMH的添加量对镀银层外观、光泽度、镀液阴极电流密度上限及沉积速度的影响,采用扫描电镜观察镀层的微观形貌。结果表明,当DMH质量浓度为20 g/L时,可获得结合力、抗变色能力良好,光泽度为232 Gs的镀银层,Jκ上限为0.76 A/dm2,沉积速率为1.263 g/(dm2·h)。     

表面活性剂T154和Span80对W/O型单重乳状液膜稳定性的影响

采用单因素实验法分别进行了表面活性剂T154和Span80制备W/O单重乳状液膜的研究。重点考察了表面活性剂体积分数、制乳搅拌速度、油内比、内相NaOH浓度和乳液静置时间对两种表面活性剂制备的乳状液膜破损率的影响并进行了比较。结果表明,T154和Span80制备的乳状液膜的破损率均随各考察因素的增大而降低或升高（除制乳搅拌速度外）,但前者降低或升高的幅度显著低于后者。实验确定了T154制备乳状液膜的最适宜条件,在此条件下,当乳状液膜静置时间为1、4、8 h时,其破损率分别为2.3%、4.7%和7.8%,显著低于Span80制备的乳状液膜的破损率9.2%、21.9%和48.4%。     

利用特定引发剂制备氨甲基吡嗪

用2-甲基吡嗪和NCS作为原料,在引发剂的引发下,经过加热、搅拌、回流等,得中间体。再加入乌洛托品,加热回流,酸化,中和,即得到较纯的氨甲基吡嗪。此方法产物较纯,效率较高,为无毒性操作。     

丁二酰亚胺的界面活性及与ZDDP的相互作用

研究了丁二酰亚胺的界面活性、对丙酮酸的增溶性能及与 ZDDP复合体系的相互作用。结果表明 ,单丁二酰亚胺的界面活性及对丙酮酸的增溶能力较强 ;丁二酰亚胺与 ZDDP复合后增溶能力有所提高。     

N－3，5－二氯苯基丁二酰亚胺的合成研究

研究了Ｎ－３，５－二氯苯基丁二酰亚胺合成工艺。详细讨论了影响产物收率的主要因素。首次提出了先经回流再脱水的新工艺，合成收率达９０％以上。     

三苯胺-PAMAM树枝分子的单／双光子荧光增强

合成了新的发光分子-4-N,N-二苯基氛基苯甲酸琉角酸亚胺(简称TBA-SCM ),利用其琉拍跳亚胺基与PAMAM所含的氛基之间高度反应活性,将三苯胺甲统基组装键合在树枝分子PAMAM (0～3G)表面,构筑新的树枝分子TBA-PAMAM.研究表明,在稀溶液(10-6)下未观测到TBA-PAMAM的荧光增强现象;当浓度...     

不同相对分子质量聚异丁烯对无灰分散剂性能的影响

以不同相对分子质量的聚异丁烯（PIB）为原料,与胺、烯酐、稀释剂等在不同条件下反应,制备润滑油无灰分散剂聚异丁烯丁二酰亚胺（PIBSI）,并测试其分散性能和抗氧化性能;考察PIB相对分子质量、中间产物聚异丁烯丁二酸酐（PIBSA）的合成工艺对PIBSI性能的影响。结果表明：随着原料PIB相对分子质量的增加,PIBSI的分散性能与抗氧化性能均有提升;与氯化法工艺相比,自由基法工艺不仅能耗低、污染小,而且合成的PIBSI性能更好;其中,由数均相对分子质量为2 300的PIB原料经自由基法工艺制备的PIBSI分散性能最佳,其油泥斑点分散值（SDT）最高可达73.15%。