N,N-二烷基乙二胺

N,N-二烷基乙二胺可用于医药、表面活性剂和涂料领域,制备方法有胺氰甲基化法、胺用氮杂环丙烷处理法和乙二胺法等。在我国,淮安华东化工研究所和北京朝福化工实验厂生产N,N-二乙基乙二胺,丹东市精细化学品厂和溧阳市蒋店化工厂生产N,N-二甲基乙二胺。     

N-十六烷基乙二胺二乙酸钠的合成及性能研究

采用大量无水乙二胺与1－Br－十六烷反应合成N－十六烷基乙二胺，然后与过量氯乙酸作用制备N－十六烷基乙二胺二乙酸，用NaOH中和，即得N－十六烷基乙二胺二乙酸钠。该产物在硬水中的差示稳定性为333，优于LAS。在相同测试条件下，产物的去污力高于LAS，发泡力明显低于LAS。     

N,N-二异丙基乙二胺的合成

以乙醇胺和浓硫酸为起始原料合成硫酸-β-氨基氢乙酯,再以氢氧化钠处理环化制得氮丙啶,然后将氮丙啶在无水三氯化铝的作用下与二异丙胺开环得到N,N-二异丙基乙二胺,并用IR和1HNMR对产物进行了表征.     

N,N-二异丙基乙二胺的合成工艺改进

以丙烯酰胺和二异丙胺为原料,创新性地采用三氟甲磺酸脯氨酸盐为催化剂,经过Michael加成反应合成N,N-二异丙氨基丙酰胺;再经过Hofmann降解反应得到N,N-二异丙基乙二胺,总收率54.0%,产品结构经过1H NMR、MS表征确证。     

双子表面活性剂N,N'-双十二烷基对苯二甲胺丙酸的合成及性能研究

以十二胺、丙烯酸甲酯和对二氯苄为原料,三氯甲烷为溶剂,合成了双子表面活性剂N,N'-双十二烷基对苯二甲胺丙酸。采用~1H NMR和~(13)C NMR对其结构进行了表征。(25±1)℃时pH对产物表面活性的影响研究结果表明:pH分别为8,10和12时,cmc分别为1.6×10~(-5),3.3×10~(-5)和2.1×10~(-5)mol/L;γ_(cmc)分别为32.39,33.24和36.94 mN/m;pc_(20)分别为2.56,2.14和2.09;Γ_(max)分别为3.45×10~(-6),3.97×10~(-6)和4.34×10~(-6)mol/m~2;A_(min)分别为0.48,0.42和0.38 nm~2。当pH=12时,随溶液温度升高,pc_(20)和A_(min)增大,Γ_(max)减小。     

可聚合单体N,N-二甲基丙烯酰乙二胺的合成条件研究

利用丙烯酸和苯甲酰氯合成丙烯酰氯(AC),AC再与N,N-二甲基乙二胺(DMAEA)合成可聚合单体N,N-二甲基丙烯酰乙二胺。通过红外光谱和核磁共振谱证实产物的结构。考察原料的物质的量比、不同缚酸剂的用量与浓度、稀释N,N-二甲基乙二胺和丙烯酰氯的二氯甲烷的量、加料顺序对产品收率的影响,得出适宜的实验条件为:n(DMAEA)∶n(AC)=1∶1.2,缚酸剂w(NaOH)=25%的用量为25mL,稀释N,N-二甲基乙二胺和丙烯酰氯的二氯甲烷的量分别为80mL和45mL,加料顺序为先加N,N-二甲基乙二胺的二氯甲烷溶液,再加缚酸剂。在上述条件下,产品最高收率可达83%。     

N,N-双十二烷基壳聚糖/聚(L-乳酸)复合膜的氢键及相容性研究

以氯仿为共溶剂,通过溶液共混,制备了不同组成的N,N-双十二烷基化壳聚糖/聚(L–乳酸)(NCS/PLLA)复合膜。利用红外光谱、热分析、WAXD及SEM探讨了复合膜的氢键作用和相容性。红外分析表明,NCS随PLLA的加入,NCS的缔合羟基伸缩振动由3430cm-1红移至3 380 cm-1、谱带变宽、吸收增强;随NCS的加入,PLLA的羰基伸缩振动由1 760 cm-1红移到1 753 cm-1。热重及热重微分分析表明,复合膜的热稳定性高于纯NCS;DSC分析表明,NCS的加入使PLLA的Tm降低,结晶度下降。WAXD分析表明,NCS的加入使PLLA在2θ=16.7°和2θ=19.1°的结晶衍射峰往低角度偏移、峰变宽、峰强逐渐减弱,当NCS为50%和75%时,PLLA的结晶衍射峰消失。SEM观察表明NCS/PLLA复合膜无相分离。实验结果表明NCS与PLLA存在较强的氢键作用,复合膜具有良好的相容性。     

双十二烷基对苯二甲酰胺丙酸钠的合成与性能研究

以十二胺、丙烯酸甲酯、对苯二甲酰氯等为主要原料经加成、酰胺化、皂化等反应合成了酰胺型羧酸盐Gemini表面活性剂——N,N′-双十二烷基对苯二甲酰胺丙酸钠(SDPA-12)。经单因素考察酰胺化反应得出最佳工艺条件为:n(N-十二烷基-β-氨基丙酸甲酯)∶n(对苯二甲酰氯)=2.2∶1,35℃回流反应8h,收率68.7%;经红外光谱、元素分析和核磁共振波谱对产物结构进行了确认。性能测定表明,25℃时SDPA-12的表面张力为27.09mN/m,临界胶束浓度为1.83×10-5mol/L。     

N-十六烷基乙二胺三乙酸钠的合成及性能

用无水乙二胺、1-溴-十六烷和氯乙酸为原料,合成N-十六烷基乙二胺三乙酸钠,以提高阴离子表面活性剂在硬水中的稳定性。性能研究表明:它在硬水中的稳定性达到4级,cmc为2 13mmol·dm-3,γcmc=34.7mN·m-1。对产物的润湿力、分散力、乳化力等其他性能也进行了研究。     

N-烷基乙二胺的制备及表征

以乙二胺和卤代烷为原料在碱性条件下发生双分子亲核取代反应,合成N-烷基乙二胺,合成产率89.05%。用元素分析、红外光谱和核磁共振波谱对合成的AEDA分子的组成和结构等进行了检测和分析,与预期合成产物AEDA结构吻合。     

一种含氮硫杂环硼酸酯的制备及摩擦学性能

以2-[2-苯并噻唑基]为原料合成了2-[2-苯并噻唑基]硫代乙醇(BTE),再以该BTE合成了一种含氮硫杂环硼酸酯(SNHB)添加剂,并采用FTIR、元素分析对其结构进行了表征。考察了BTE、SNHB的油溶性、热稳定性以及SHNB的水解稳定性。采用四球摩擦磨损试验研究了BTE及SNHB在菜籽油中的减摩、抗磨以及极压性能。采用SEM、EDS观察和分析了钢球磨斑表面形貌及元素。研究结果表明,合成的产物为目标产物BTE和SNHB;在相同的试验条件下,SNHB和BTE在菜籽油中完全溶解,具有较好的油溶性;SNHB和BTE的分解温度范围分别是从270.50~396.01℃、253.04~326.83℃,两者均具有良好的热稳定性,且SNHB的热稳定性优于BTE;SNHB的水解时间超过7天,而市售的硼酸三异丙酯仅为10 min,SNHB有较好的水解稳定性;在不同载荷、添加比例等条件下SNHB的摩擦学性能明显优于BTE。     

Bismaleimides blend with a synthesised phosphorus-containing benzoxazine and its mechanical and tribological properties

ABSTRACT

The phosphorus-containing benzoxazine-bismaleimides (PBOZ-BMI) resin was fabricated by blending the synthesised phosphorus-contained benzoxazine monomer (PBOZ) with bismaleimides (BMI). The influence of PBOZ content on the mechanical and tribological properties of PBOZ-BMI resin was researched. The results showed that suitable addition of PBOZ can enhance the mechanical properties and decrease the frictional coefficient and wear rate of PBOZ-BMI resin to some extent. The improvement of mechanical properties of PBOZ-BMI can be attributed to the cross hydrogen bonding and network interpenetrating. The wear mechanism of the PBOZ-BMI resin was converted from fatigue wear to adhesive wear after the addition of PBOZ, observed from the wear surface of the materials by scanning electron microscopy (SEM). The enhancement of tribological properties is due to the high heat resistance of PBOZ, which can inhibit the adhesive wear during the wear effective.     

Synthesis of polyphenylmethylsiloxanes and their enhancement on tribological properties of titanium complex grease

Polyphenylmethylsiloxanes (PPMSs) with the phenyl/methyl mole ratios of 0.25:1–0.75:1 were facilely synthesized using phenylmethyldichlorosilane, diphenyldichlorosilane, dimethyldichlorosilane, and hexamethyldisiloxane as the raw materials with the hydrolysis-condensation method. The molecular weights (M _w) of the as-synthesized PPMSs ranged from 1248.7 to 27 014.0. The maximum molecular weight was obtained at the phenyl/methyl ratio of 0.65:1. Titanium complex greases were prepared by using titanium carboxylate as the thickener and PPMS/mineral oil (KN4010) as the mixed base oil. When the weight percentage of PPMS (phenyl/methyl mole ratio of 0.45:1) in the mixed base oil was 20%, the dropping point of the resultant titanium complex grease increased by 21 °C as compared with the sole mineral oil-based titanium complex grease. The friction coefficient and the wear scar dimension were 0.54 and 0.69 times those of the sole mineral oil-based titanium complex grease, respectively. According to thermogravimetric analysis–differential scanning calorimetry analysis, the working temperature of the titanium complex grease could reach 240 °C. The addition of PPMS in the titanium complex grease obviously improved its thermal stability and tribological properties. The present work developed a new category of titanium complex grease using PPMS and mineral oil as the mixed base oil. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47168.     

表面修饰铁纳米颗粒的制备及其摩擦性能

以次亚磷酸钠为还原剂,双烷氧基二硫代磷酸铵盐为修饰剂,在四氢呋喃-饱和食盐水的两相体系中合成了表面修饰的铁纳米颗粒,采用红外光谱仪、热分析仪等仪器对其进行了结构表征;在透射电子显微镜下观测所制备的铁纳米颗粒的形貌;在四球摩擦试验机上测试了其摩擦性能,并在扫描电子显微镜和能谱分析仪上对钢球表面进行了形貌观测和表层成分分析。结果表明,铁纳米颗粒在低极性有机溶剂中具有良好的分散性,并具有良好的抗磨和承载能力。磨斑的表面分析表明,铁纳米颗粒添加剂在边界润滑下形成了一层含Fe、S、P和O元素的表面膜是其具有良好摩擦学性能的主要原因。     

A novel method to prepare self‐lubricity of Si3N4/Ag composite: Microstructure,mechanical and tribological properties

Si₃N₄/Ag composites were firstly prepared through SPS technology, using Si₃N₄ and AgNO₃ as raw materials. Utilizing the coordination bonding of Ag⁺ ions with nitrogen atoms of Si₃N₄, in situ generated Ag particles about 1 μm were tightly anchored on Si₃N₄ surface, thereby preventing the outflow of silver during sintering process. Meanwhile, smaller silver particles about 20 nm were located at the grain boundaries of Si₃N₄, which effectively improved the mechanical and tribological properties of Si₃N₄‐based composites. Finally, the Si₃N₄/Ag composites reinforced by Ag particles showed a friction coefficient of 0.48 ± 0.01, wear rate of 1.79 × 10^?6 mm³ N^?1 m^?1 and fracture toughness of 7.05 ± 0.2 MPa m^1/2, respectively.     

N，N，N-三（2-甲基苯并咪唑）胺氧钒配合物的合成、表征及光谱性质研究

本文用微波法合成了配体N,N,N-三（2-甲基苯并咪唑）胺,并以无水甲醇为溶剂,在常温条件下合成了配体与硫酸氧钒的配合物。通过红外光谱和元素分析对其结构进行了表征,并对其紫外吸收峰随pH值的变化及荧光性质进行了研究,结果表明配体在紫外光区吸收峰的强度随pH值的增大而降低,而配合物吸收峰的强度随pH值的增大先降低后增高,二者均发生红移;氧钒配位后使配体发生荧光猝灭。     

二氧化钛微球合成、表面修饰及摩擦学性能

通过溶剂热法简便地合成了具有统一形貌和良好结晶度的锐钛矿型二氧化钛微球,并使用硬脂酸对所制备的产品进行表面改性,改性后的产品可以很容易的分散在非极性有机溶剂或者矿物油中形成均匀溶液,且上述溶液在室温环境下可较长时间保存而不出现沉淀。其原因是由于改性后产品表面存在长链羧酸基团,故而在油品中具有良好的分散性。通过 X 射线粉末衍射法 (XRD),扫描电镜 (SEM),红外测试 (FT-IR),热重测试 (TGA) 等检测手段对其晶体结构、晶粒大小以及产品表面形貌进行表征,并且对产品的形成机理进行了探讨。通过四球摩擦试验机考察了修饰后产品作为液体石蜡为基础油润滑添加剂的摩擦学性能。结果表明,经过修饰后的产品拥有良好的抗摩减磨性能并且可以很好的提高液体石蜡载荷能力。     

Evaluation under temperature cycling of the tribological properties of Ag-SiNx films for green tribological applications

Nowadays, one of the most important challenges in the tribology field is to avoid the excessive consumption of soft metals such as Ag at elevated temperatures through the re-design of the self-lubricant films, to achieve the long-term lubricant under the temperature-cycling environments, for widely used in real industrial applications. This paper took up this challenge to develop a novel green film, by composing nano-particles Ag into the amorphous SiN_x matrix using magnetron sputtering system, for achieving the long-term lubricant under the room temperature (RT)-500 °C temperature-cycling conditions. Results showed that the film exhibited a dual-phase of face-centered cubic (fcc) Ag and amorphous SiN_x. An excellent RT-500 °C wear-resistance performance was observed for the films with the Ag content of 1.3–9.4 at.%, whilst the film at 15.8 at.% Ag exhibited the best anti-frictional performance (COF 0.3–0.5 for RT-500 °C conditions) at the cost of wear rate. The self-lubricant tribology behaviors under the RT-500 °C cycling conditions were mainly attributed by the synergism of: (1) mechanical properties, (2) excellent high-temperature chemical stability of SiN_x matrix, and (3) the lubricant nature of Ag and its elevated temperature diffusion behaviors.     

Mechanical and tribological properties of SiC whisker-reinforced SiC composites via oscillatory pressure sintering

SiC whisker (SiCw)-reinforced SiC composites were prepared by an oscillatory pressure sintering (OPS) process, and the effects of SiCw content on the microstructure and mechanical and tribological properties of such composites were investigated. The addition of SiCw could promote the formation of long columnar α-SiC, and the aspect ratio of α-SiC grains first increased and then decreased with the increase of SiCw content. When the SiCw content was 5.42 wt%, the relative density of the SiC–SiCw composite reached up to 99.45%. The SiC–5.42 wt% SiCw composite possessed the highest Vickers hardness, fracture toughness, and flexural strength of 30.68 GPa, 6.66 MPa·m^1/2, and 733 MPa, respectively. In addition, the SiC–5.42 wt% SiCw composite exhibited the excellent wear resistance when rubbed with GCr15 steel balls, with a friction coefficient of .76 and a wear rate of 4.12 × 10⁻⁷ mm³·N⁻¹·m⁻¹. This could be ascribed to the improved mechanical properties of SiC–SiCw composites, which enhanced the ability to resist peeling and micro-cutting, thereby enhancing the tribological properties of the composites.     

Preparation and anisotropic tribological properties of MoAlB/Al laminated composites

The unique microstructure of biomaterials provides inspiration in materials structure design and performance breakthroughs. Here we prepared a MoAlB reinforced Al matrix composites with laminated structure and strong interfacial bonding. This work mainly focuses on the relationship between tribological properties of the MoAlB/Al laminated composites and the MoAlB layer orientation. The results show that the tribological properties of the composites deeply depend on the relation of sliding direction VS. the MoAlB layer orientation, while the dependency gradually decreases with the MoAlB content increasing. The friction coefficient and wear rate of the composites can be decreased by 55.5% and 95.1%, lower than those of pure Al, when 15 vol% MoAlB reinforcement is added. The friction and wear mechanisms of the MoAlB/Al laminated composites are proposed, and the outstanding tribological properties are ascribed to the formation of tribochemical worn film and different stress states caused by the laminated structure.