二烷基二硫代氨基甲酸钼添加剂的研发进展

二烷基二硫代氨基甲酸钼主要用于润滑油、润滑脂中,可以提高内燃发动机燃油经济性、持久性,是适应GF-4、GF-5汽油机油规格的节能、环保添加剂。文章叙述了兼具抗磨减摩、极压和抗氧化性能的润滑油添加剂二烷基二硫代氨基甲酸钼的合成技术,简述了二烷基二硫代氨基甲酸钼的润滑和热分解机理,对二烷基二硫代氨基甲酸钼的表征方法进行概括,并对我国二烷基二硫代氨基甲酸钼的发展方向提出建议。     

二烷基二硫代氨基甲酸盐的润滑性能

用四球试验机评价了二丁基二硫代氨基甲酸酯(V7723)、二烷基二硫代氨基甲酸钼(MoDDC)、二戊基二硫代氨基甲酸锑(SbDDC)、二丁基二硫代氨基甲酸铋(BiDDC)和二丁基二硫代氨基甲酸锡(snDDC)在150SN中的极压和抗磨性能,测试结果表明,SnDDC和SbDDC的抗磨性能较好,而BiDDC的极压性能较好.二烷基二硫代氨基甲酸盐间还具有协同效应.     

X-ray Absorption Spectroscopy and Atomic Force Microscopy of Films Generated from Organosulfur Extreme-Pressure (EP) Oil Additives

This study examines the interaction of sulfur-based oil additives on steel. Sulfurized isobutylene, dialkyldithiocarbamate and sulfurized esters were the additives investigated in this report. For the first time, X-ray absorption near edge structure (XANES) spectroscopy has provided detailed insight into the chemistry of both the thermo-oxidative and tribochemical films generated from these additives. It was found that the chemical nature of these films was strongly dependent on the operating environment for the additives. The XANES revealed that thermally, all three S additives reacted very similarly with steel to form a film mainly comprised of iron sulfate at temperatures as low as 100 °C. The ample supply of diffused oxygen from the base oil along with oxide naturally present on the substrate allowed for the complete oxidation of the S from the decomposed additive to iron sulfate. Tribochemical films were comprised of different forms of sulfur than observed for the thermo-oxidative films. The moderate AW conditions yielded a mixture of both oxidized and reduced forms of sulfur, with pyrite, FeS₂, being the major constituent. Rubbing between the steel pin and the substrate partially depleted the oxide layer present, allowing the additive to interact intimately with the fresh substrate, yielding FeS₂. Under extreme-pressure conditions, complete removal of the oxide layer occurred with a drastic increase in the interfacial temperatures between the pin and v-block, allowing for the complete thermal decomposition of FeS₂ to FeS to occur. AFM imaging of the AW films revealed the presence of tiny smooth domains randomly oriented, which were completely different from the pad-like structures observed for AW films generated from a typical ashless thiophosphate additive. The inability of the sulfur-based additives to form large pad-like structures, which can ultimately support the load, resulted in poor AW protection to the metal.     

与螯合疗法相关的二烷基二硫代氨基甲酸镉的结构和性能

二烷基二硫代氨基甲酸盐是镉离子中毒的有效解毒剂 ,本文研究了四种二烷基二硫代氨基甲酸镉的化合物 [Cd(R2 dtc) 2 ]2 (R =Me ,Et,Pr,iPr)的合成 ,并采用EA ,IR ,Raman ,UV ,TGA -DGA进行结构表征     

二烷基二硫代氨基甲酸钼与芳胺抗氧剂的协同效应

采用差示扫描量热法(DSC)考察了二烷基二硫代氨基甲酸钼(MoDDC)和芳胺类抗氧剂在聚α-烯烃合成润滑油中的热氧化安定性。DSC静态和动态氧化实验均表明:虽然MoDDC的抗氧性能明显差于抗氧剂丁基辛基二苯胺和对,对-二异辛基二苯胺,但MoDDC与胺类抗氧剂复合后,其起始氧化温度和氧化诱导时间比只用单剂时相应提高38℃和延长3倍以上,表现出良好的抗氧协同效应。     

二烷基二硫代氨基甲酸钼加氢催化剂的合成及表征

合成了一种新型重油悬浮床加氢裂化油溶性催化剂二烷基二硫代氨基甲酸钼,考察了不同合成条件下催化剂产率和金属回收率;利用SEM,TEM和动态光散射仪表征了该催化剂硫化后的性质,并通过XPS对其自硫化性能进行了研究。结果表明,合成该催化剂的最佳物料摩尔比为H_2SO_4∶Na_2MoO_4∶CS_2∶C_8H_(19)N∶Na_2S·9H_2O=1.3∶1∶1.5∶1.5∶1;最佳反应条件:温度90℃,反应时间5 h。在重油悬浮床加氢条件下,催化剂具有自硫化功能,无需添加硫化剂,与环烷酸钼催化剂相比,该催化剂具有更好的加氢活性,在催化剂质量分数200μg/g、反应温度430℃、压力7.0 MPa下,单位生焦率下的轻油收率达到42.4%,总生焦量仅为0.96%。     

油溶性二烷基二硫代氨基甲酸钼的合成及性能应用

文章选用三氧化钼、无机酸以及二烷基胺为原料合成了一种二烷基二硫代氨基甲酸钼,用红外和质谱对合成产物进行了表征,实验结果与目标产物的特征结构一致。采用四球摩擦磨损试验机以及SRV考察了其在基础油及成品油中的抗磨性能和减摩性能,结果表明：这种二烷基二硫代氨基甲酸钼具有良好的减摩性能,并与T203有很好的协同作用。     

ZDDP与MoDTC在含酯类油的PAO基础油中的抗磨性能研究

将二烷基二硫代磷酸锌(ZDDP)和二烷基二硫代氨基甲酸钼(MoDTC)分别加入聚ɑ-烯烃（PAO）、PAO与分散剂、PAO与酯类油3种试样中,进行四球机抗磨试验,考察ZDDP和MoDTC对不同试样的感受性。将ZDDP和MoDTC两种添加剂进行复配试验,并通过扫描电镜观察磨斑形貌。试验结果表明：酯类油能够很好地提高PAO基础油的抗磨性能,其质量分数为5%～10%时即可达到较好的抗磨性能;PAO与分散剂试样中,增大ZDDP的加入量不能有效地降低磨斑直径,增大MoDTC的加入量可降低磨斑直径;PAO与酯类油试样中,随着ZDDP加入量的增加,磨斑直径减小,ZDDP的抗磨效果优于MoDTC;两种添加剂复配后与单剂相比无明显的增效作用。磨斑形貌分析结果表明：加入MoDTC的基础油试验测得的磨斑表面平整,对摩擦表面修复作用更佳,同时添加ZDDP与MoDTC的基础油,试验测得的表面磨痕不规则,两剂具有竞争关系。     

S-N型润滑添加剂的合成及其摩擦学性能研究

合成一种新型环境友好型、无灰、非磷极压抗磨剂——含羟基二烷基二硫代氨基甲酸衍生物(DDCSD)。采用红外光谱仪对其结构进行表征,利用热分析仪考察其热稳定性,使用四球试验机及SRV考察其在复合锂基润滑脂中的摩擦学性能,并用扫描电子显微镜及X射线光电子能谱分析摩擦表面形貌及表面化学成分。结果表明,DDCSD具有良好的热稳定性,能有效提高基础脂的抗磨、减摩及极压性能,可作为多功能润滑油脂添加剂ZDDP的替代品。这是由于DDCSD在摩擦过程中发生化学吸附及摩擦化学反应,在金属表面上形成了一层具有抗磨减摩性能的边界润滑膜,从而起到抗磨减摩的作用。     

Synergistic lubricating effect of several ashless dithiocarbamates with Mo-donor additives

Several kinds of alkylenebis(dialkyldithiocarbamates) were synthesized and the tribological properties as additives in base oil (100N) and Li-soap greases were evaluated using 4-ball tester and SRV tester (Schwingreibverschleissprüfung für Schmierstoffe). The results show that all additives reduce wear. Especially, when Mo(Zn)-donor additives such as Mo-DTC, Zn-DTP, and a vegetable oil modified organomolybdenum complex were blended in base oil containing methylenebisdibutyldithiocarbamate as sulfur donor, synergism was seen both in terms of oxidation stability through thermo gravimetric analysis (TGA) and wear properties using a 4-ball tester. TGA showed that oils containing sulfur-donor and Mo(Zn)-donor additive mixtures possess improved oxidation stabilities. Also, these oils have good antiwear properties under mild pressure conditions. The elemental composition of the antiwear films generated on steel counterfaces were investigated with scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). It was found that sulfur-donor and Mo-donor additives reacted with the counterface metal and generated a surface protective film consisting of FeS and MoS₂.