表面修饰硼酸镧极压性能研究

优化了PyDDP制备工艺条件，采用三步工艺制备了PyDDP表面修饰剂，采用红外光谱确认了PyDDP的结构。对PyDDP修饰硼酸镧制备的工艺条件进行了正交优化，获得了粒径在10nm左右的PyDDP修饰硼酸镧，分别采用红外光谱、XRD、TG-DTA研究了材料的性能，采用四球实验测定了PyDDP修饰材料的极压性能，其最大无卡咬负荷为749N，同时采用EDX对蚀球表面形貌和元素进行了分析，在蚀球表面发现了稀土元素。对PyDDP修饰硼酸镧结构与材料极压性能之间的关系进行了分析，指出稀土渗透层和稀土摩擦催渗硼的作用是该材料具有良好极压性能的主要原因。     

PyDDP表面修饰纳米硼钼剂的制备及极压性能研究

以二烷基二硫代磷酸吡啶（PyDDP）为表面修饰剂, 分别制备了PyDDP表面修饰纳米硼酸镧和PyDDP表面修饰纳米二硫化钼, 并将两者复配制备了PyDDP表面修饰纳米硼钼剂. 采用IR、XRD、TEM等分析方法对表面修饰纳米微粒进行了表征. 结果表明, 纳米硼钼剂由硼酸镧和二硫化钼微粒组成, 粒径在30～50nm之间. 通过四球试验研究了PyDDP表面修饰纳米硼钼剂的摩擦学性能, 并利用SEM、EDXA、XPS等方法对蚀球表面形貌和表面元素进行了分析. 结果表明, PyDDP表面修饰纳米硼钼剂具有较好的极压抗磨性能, 表面元素在摩擦副表面形成无机化学反应膜是具有良好的极压性能的主要原因.     

表面修饰纳米硼酸镧的制备及极压抗磨性能研究

用硼砂、硝酸镧、适当的修饰剂及修饰工艺，制备了表面修饰纳米硼酸镧极压抗磨添加剂，以四球实验评价了其极压抗磨性能。结果表明，纳米硼酸镧的最大无卡咬负荷（PB)比目前普遍使用的极压抗磨剂二烷基二硫磷酸锌高8%，且磨痕直径较小。用X射线电子能谱分析了蚀球磨斑表面的化学成分，在磨擦副表面发现了B、La、Fe等的氧化物，证明了此类添加剂能够在摩擦过程中不仅能生成以氧化硼、氧化铁等为主要成分的边界润滑膜，还可能形成含澜、硼的渗透层，这是此类添加剂具有良好抗磨减摩性能的主要原因。     

硬脂酸修饰LaPO4和Ce/LaPO4纳米微粒的制备及其摩擦学性能

采用共沉淀表面修饰法,制备了硬脂酸修饰LaPO4和Ce/LaPO4纳米微粒,用红外光谱仪、X射线衍射和透射电子显微镜对表面修饰纳米微粒的结构、形貌进行了表征,考察了表面修饰纳米微粒在溶剂中的分散性,利用四球试验机考察了表面修饰纳米微粒的摩擦学性能,并用扫描电镜对钢球磨斑表面形貌进行了分析.结果表明,硬脂酸修饰LaPO4...     

表面修饰的纳米硼酸镁的制备及其摩擦学研究

为开发可作为硫化烯烃替代物的润滑油添加剂,制备了一种表面修饰的纳米硼酸镁粒子(T-MgBN),采用ICP-AES、XRD和TEM对其结构进行了表征.结果表明:制备的T-MgBN为无定型、平均粒径为50 nm的纳米粒子,且表面吸附了表面修饰剂.利用四球摩擦磨损试验机对在一种新型调油工艺下调制的T-MgBN试油摩擦学性能进行了评价,并和硫化异丁烯(T321)的摩擦学性能进行了比较.采用SEM及XPS对钢球磨损表面形貌和元素状态进行了分析.结果表明:T-MgBN在矿物油中具有优异的抗磨、减摩件能.随着剪切力的增大,T-MgBN在摩擦副表面吸附、沉积形成了一层保护膜,并且和表面吸附的表面活性剂以及摩擦副发生了摩擦化学反应生成了B_2O_3、BN、Fe_2O_3和FeB等物质.     

油酸修饰PbS纳米微粒的原位合成与抗磨性能研究

将纳米材料作为润滑添加剂已经成为当前摩擦学研究的热点.为了制备具有良好抗磨性和分散性的纳米添加剂,对油酸修饰PbS纳米微粒的合成方法与润滑性能进行了研究.在液体石蜡中原位合成了油酸修饰的PbS纳米微粒,将其在离心机中离心后可获得稳定的溶液.采用红外光谱、透射电子显微镜(TEM)对产物结构和形貌进行了表征,利用四球摩擦磨损试验机对其作为润滑油添加荆的抗磨性能进行了评价,并用扫描电子显微镜(SEM)对磨斑表面形貌进行了观察.在试验基础上,探讨了纳米微粒在溶液中的稳定机制.结果表明,原位合成的PbS微粒表面有油酸修饰层存在,从而使其在液体石蜡中具有良好的分散性能,粒度小于15nm,油酸修饰的PbS纳米微粒作为添加剂在液体石蜡中的添加量为0.3%(质量分数)时的磨斑直径最小,磨斑表面光滑平整.     

纳米材料表面修饰的研究进展

通过材料的表面修饰与包覆以改善材料的表面性质乃至改变材料的相结构和性质,已经成为纳米材料制备和应用的关键技术.综述了近年来纳米微粒表面修饰的研究进展,并对纳米微粒表面改性的各种方法原理及其特点进行了归纳和分析.     

层-核结构纳米硼酸钡/石蜡微球的合成与摩擦学研究

采用相转移技术合成了直径为6～30nm的无定型硼酸钡粒子,采用TEM、XRD对其结构进行了表征.将此纳米粒子与石蜡复合制备出层-核结构纳米硼酸钡/石蜡微球,用光学显微镜对其形貌进行了观察,大小在40～70靘之间.将微球加入水中制备出水基润滑剂,采用环块与四球摩擦磨损试验机对润滑剂的抗磨减摩性能进行了评价,发现相转移合成过程中表面活性剂的用量对纳米硼酸钡的形貌具有决定性影响.由此制备的水基润滑剂的摩擦学性能显著依赖于微球在润滑剂中的含量,尤其是纳米硼酸钡在微球中的含量,SEM表征发现石蜡在摩擦副上形成了膜.纳米硼酸钡的存在提高了抗磨减摩膜的强度.     

PS／OMMT纳米复合材料作为润滑油添加剂的摩擦学性能

用乳液聚合法制备了聚苯乙烯/有机蒙脱土(PS/OMMT)纳米复合材料,并利用 XRD对其结构进行表征.利用四球机考察了纳米复合材料在AN 10油中的摩擦学性能,表明所合成的PS/OMMT纳米杂化材料能提高基础油的抗磨性能及承载能力,降低其摩擦系数;复合材料中OMMT含量对摩擦学性能影响很大.EDX能谱研究结果表明,在低负荷下PS/OMMT纳米复合材料在钢球表面铺展成膜,在高负荷下,聚合物分解,裸露出纳米结构的高度分散蒙脱土片层具有高活性,能在钢球的磨斑表面成膜,改善润滑油高负荷下的摩擦学性能.     

纳米偏硼酸钙/还原石墨烯润滑添加剂的制备及摩擦学性能

为了研究表面改性纳米偏硼酸钙/还原石墨烯润滑添加剂的合成方法,以偏硼酸钙、还原石墨烯为原料,油酸为修饰剂,利用等离子体辅助球磨制备纳米偏硼酸钙/还原石墨烯复合粉体,并测试其摩擦学性能.采用扫描电镜、透射电镜、X射线衍射仪和红外光谱仪对纳米偏硼酸钙/还原石墨烯复合粉体进行形貌观察;采用形状测量激光显微镜、扫描电镜对摩擦副表面进行测试;采用MOAⅡ油液分析光谱仪对摩擦油样进行检测.结果表明:在钢球机械研磨和等离子体热效应的耦合作用下,等离子体辅助球磨10 h的偏硼酸钙与还原石墨烯继续球磨10 h后,被细化为10 nm左右的颗粒状,并均匀地负载于还原石墨烯上.等离子体快速加热使得偏硼酸钙粉体表面发生热爆,部分偏硼酸钙飞溅在还原石墨烯上,并随即被其包裹为球状复合结构.等离子体辅助球磨10 h为偏硼酸钙表面引入羧基基团,并在后续球磨中与还原石墨烯表面的羟基发生酯化反应,原位完成油酸对偏硼酸钙和还原石墨烯的表面改性,使得纳米偏硼酸钙/还原石墨烯复合粉体在5W-40型机油中具有良好的分散性.在摩擦过程中,比表面积大的还原石墨烯不断吸附在摩擦表面,同时被还原石墨烯包裹为球状的纳米偏硼酸钙粒子,使摩擦副表面产生多活动中心的滚动摩擦,从而有效改进复合油的减摩抗磨性能.     

Nondestructive characterization of surface chemical wear films via X-rays

This work describes and demonstrates a suite of techniques for the non-destructive examination of surface films formed from oil additives. X-Ray diffraction, reflectivity and fluorescence have been used in grazing-incidence geometry to provide information on the thickness, roughness, density, structure and composition of the layers that compose reaction films. The lubricating oils were not rinsed off the surfaces of the samples before analysis. Films were formed from neat polyalphaolefin (PAO) oil and PAO with chloroform, dimethyl disulfide, or zinc or molybdenum dialkyl dithiophosphate additive. A thick layer of crystalline FeO formed during wear lubricated by neat PAO.     

Metal-doped (Ti, WC) diamond-like-carbon coatings: Reactions with extreme-pressure oil additives under tribological and static conditions

In contrast to non-doped diamond-like-carbon (DLC) coatings, reliable chemical evidence of the reactions between metal-doped DLC coatings and oil additives under tribological conditions using state-of-the-art surface-sensitive chemical analyses is still scarce. In this study we have investigated the reactivity of metal-doped (Ti, WC) DLC coatings with the extreme-pressure (EP) dialkyl dithiophosphate additive — without the presence of a steel counter body in the contact that befogs the actual coating reactions. Static “reactivity” experiments without any tribological or mechanical effects were also performed to provide a further insight into the lubrication mechanisms. The results confirmed the chemical reactions between the EP additive and all the DLC coatings, as well as their oxidation during the tribological contacts. We measured an about 10-times higher chemical activity (a 25-fold P/S ratio increase) for the Ti-doped DLC compared to the WC-doped or non-doped DLC, which also agrees with it having the lowest amount of wear in this study. We suggest that the Ti-DLC boundary lubrication is achieved via binding sites at the O vacancies present in the Ti-doped DLC coating. The data also clearly show, in contrast to most of literature reports, that even though small, some direct chemical activity between the W-DLC and the dialkyl dithiophosphate EP additive is also possible without any iron catalytic effect. However, the chemical changes were significantly smaller, also allowing coating graphitization, which might be one of the reasons for the 50% higher wear of the WC-doped compared to the Ti-doped DLC.     

Effects of molybdenum dithiocarbamate and zinc dialkyl dithiophosphate additives on tribological behaviors of hydrogenated diamond-like carbon coatings

The tribological behaviors of hydrogenated diamond-like carbon (DLC) coatings under varied load conditions lubricated with polyalpha olefin (PAO), molybdenum dithiocarbamate (MoDTC) and zinc dialkyl dithiophosphate (ZDDP) additives were investigated in this paper. Hydrogenated DLC coatings were synthesized through the decomposition of acetylene by the ion source. The tribological performances were measured on a SRV tribometer. The morphologies and chemical structures of the DLC coatings were investigated by the scanning electron microscope (SEM), Raman spectrometer (Raman) and X-ray photoelectron spectroscope (XPS). It was shown that the low friction and high wear were achieved on the hydrogenated DLC coating under MoDTC lubrication, while low wear was found on the hydrogenated DLC coating lubricated by ZDDP. The primary reason was attributed to different tribofilms formed on the contact area and the formation of graphitic layer. Both factors working together leaded to quite different tribological behaviors.     

含铝PSBR复合橡胶的制备及其力学性能

利用铝的醇盐与PSBR季铵盐乳液反应,制成含铝有机－无机杂化弹性体胶片,再与天然橡胶进行并用,制得含铝PSBR复合硫化胶,这种复合硫化胶具有优良的力学性能和独特的抗震作用,用IR和NMR以及其它方法分析了其相关结构.     

Synthesis and characterization of a polyacetylene derivative with phenylazobenzene moieties

A new polyacetylene derivative was prepared by the activated polymerization of 2-ethynylpyridine by using 4-(phenylazo)benzoyl chloride without any additional initiator or catalyst in high yield. The chemical structure of poly[2-ethynyl-N-(4-(phenylazo)benzoyl) pyridinium chloride [PEPABPC] was characterized by such instrumental methods as NMR, IR, and UV-visible spectroscopies to have a conjugated polymer backbone system with the designed azobenzene moieties. The electrooptical and electrochemical properties of PEPABPC were studied. The photoluminescence spectrum showed that the PL peak is at 597 nm corresponding to the photon energy of 2.07 eV. The cyclovoltammograms of PEPABPC exhibited the irreversible electrochemical behaviors between the oxidation and reduction peaks. The oxidation current density of PEPABPC versus the scan rates is approximately linear relationship in the range of 30 mV/sec-150 mV/sec. It was found that the the kinetics of the redox process of this polymer is controlled by the reactant diffusion process from the oxidation current density of PEPABPC versus the scan rates.     

纳米二氧化钛制备工艺的研究

采用sol—gel法,以钛酸丁酯为原料制备纳米级二氧化钛溶胶及粉体;研究了水分含量、抑制剂种类、溶剂种类以及焙烧温度等因素对纳米二氧化钛制备的影响,从而进一步优化了粉体制备与负载化的工艺条件;并用X射线、SEM表征了所制纳米TiO2的晶型、粒径和形貌。     

一种光敏CTP版材成像体系的研究

研究一种有望应用于计算机直接制版（Computerto Plate,CTP）光敏成像版材配方。先以双酚A和甲醛为原料合成一种交联剂,利用IR和TG进行结构表证;将它和一种线性酚醛树脂配制成涂膜液,掺加三嗪类光生酸剂,通过曝光、烤版、显影研究成像过程,并利用膜厚变化和表面亲和性变化研究成像性能。     

可生物降解型哌嗪衍生物的摩擦学性能

为了研究新型哌嗪衍生物的可生物降解性和摩擦学性能,设计合成了环保型润滑油添加剂1,4-双(二硫代甲酸乙酰乙胺)哌嗪(DAP)。采用元素分析和红外光谱进行结构表征,考察了其热稳定性能、可生物降解性和在液体石蜡油(LP)中的极压抗磨性能,利用扫描电子显微镜(SEM)和X射线光电子能谱仪(XPS)分析了钢球的磨损表面形态。结果表明:合成的化合物热稳定性能好并具有良好的可生物降解性;化合物添加到LP中后具有很好的极压抗磨性能,并在摩擦过程中发生了化学吸附及摩擦化学反应,在摩擦区域金属表面上形成了一层复杂边界润滑膜,从而起到了良好的抗磨减摩的作用。     

Preparation of National CRMs of Active Compounds from Natural Products

According to the standard of GB/T1500.3-2008 and the guidelines of ISO/REMCO, the preparation of National Certified Reference Materials (CRMs) of active compounds was composed of the following two aspects: preparation and certification. This paper presents an example of the preparation of biochanin A to illustrate the preparation of National CRMs of active compounds from natural products. Firstly, the target compound was extracted and purified from crude materials. Then,its chemical structure was identified by UV spectrum, IR spectrum, ESI-MS, and NMR. The purity of the compound was determined by HPLC with the area normalization method. The certified value assessed by comparing the purity values from six independent qualified laboratories and the value of uncertainty were given. Thermal analysis, residual solvent, homogeneity testing and stability testing was tested in the process.