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The poly(diphenylamine) derivative (PDPA) as amine antioxidant was synthesized via diphenylamine, styrene, and formaldehyde. The steps of the synthesis were discussed in detail, and the structure of PDPA was fully characterized with multiple analysis techniques. Furthermore, the anti-oxidative properties of PDPA were evaluated through oxidation–corrosion tests and differential scanning calorimetry. It was found that PDPA significantly improved the oxidation stability of base oils, especially pentaerythritol ester when it was added at concentrations of only 0.5 wt % to 0.8 wt %. Thermogravimetric analysis shows that anti-oxidation behavior of PDPA is better than traditional additive p, p-dioctylphenylamine. The synthesized PDPA antioxidant is a potential alternate additive in high-temperature conditions.

The styrenated sulfur- and phosphorus-free organic titanate (STAE) was synthesized via an in situ method with soybean oil, diethanolamine, and isopropyl titanate. The tribological and antioxidant behavior of the as-synthesized STAE as an additive in PAO was evaluated by a four-ball test, a rotary oxygen bomb test (ROBT), and differential scanning calorimetry (DSC), and its oxidative stability was estimated through thermogravimetric analysis (TGA). The as-synthesized STAE exhibits excellent antiwear and load-carrying capacities as well as good antiwear synergism with zinc dialkyldithiophosphate (ZDDP) in poly-α-olefin (PAO). STAE in PAO also showed good synergistic antioxidation effects with the traditional additive p,p-(dioctyldiphenylamine (DODPA). This is because STAE can effectively reduce the oxidation rate of DODPA, which was confirmed by the results of Fourier transform infrared spectroscopy (FTIR) and gas chromatography-tandem mass spectrometry (GC/MS).

A novel method of catalytic thermometric titration has been developed for the determination of the acidity of oils using titration with KOH in isopropanol as titrant. The amounts of oil, concentration and delivery rate of titrant, volumes and types of thermometric end-point indicator were investigated. The results show that mixture of acetone and chloroform used as indicator exhibits strongly exothermic effects to reflect end point obviously. The results obtained from the thermometric titration have good agreement with standard potentiometric and visual titration methods. The procedure is fast, easy to use, accurate, and highly reproducible to measure lower acidity in coloured oils. It is very suitable for the routine process and quality control of many types of oils.

The different size of microplastic in the environments may affect the fate and effects of traditional hydrophilic chemicals. The effect of reaction time, pH, salinity and concentration on the adsorption of lubrication oil on the 20–140 μm sized polystyrene (micro-PS) and 50 nm polyethylene (nano-PE) were presented. The adsorption kinetics and isotherms of nano-PE and micro-PS can be satisfactorily fitted by pseudo-second-order kinetic model and Langmuir, respectively. The adsorption of lubrication oil on nano-PE and micro-PS significantly increased with increasing concentration of salinity, indicating that the outer-sphere surface complexation dominated lubricating oil sorption on nano-PE and micro-PS. The maximum adsorption capacity of lubricating oil on nano-PE and micro-PS was 6.8 and 5.2 g/g at pH 5.0 and 293 K, respectively. These results are of crucial importance to the application of microplastics as the promising adsorbent in natural environments.

Water content in jet fuels is detected by thermometric titration (TMT), and the optimal detected system is 2,2-dimethoxypropane as titrant, cyclohexane and isopropanol as titration solvents, and methanesulfonic acid as catalyst in this method. The amounts of oil, concentration and delivery rate of titrant, volumes, and the reliability and accuracy of thermometric titration were emphasized. The results show that the accuracy, validity, and reliability of TMT are excellent by different indicated spiked water contents. The obtained results between TMT and Karl Fischer titration have been proven to be in accord. But, the duration of titration merely spends 3–5 min in the whole process, greatly shortening the detected time. Therefore, rapid and accurate determination of trace water in a jet fuel can be realized by TMT.

A first atom-economic [2 + 2] cycloaddition/1,6-conjugate addition cascade of yne-allenones with C-nucleophiles including 1,3-dicarbonyls and α,α-dicyanoolefins under base-promoted conditions has been established, enabling the direct construction of C(sp3)–C(sp3) bonds to generate cyclobuta[a]naphthalen-1-ols with generally good yields. These resulting products have a cyclobutene unit that contains both an aryl and alkyl group.

Ethylene glycol methyl fan is the main components of Anti icing additive of jet fuel. the volume percent of Anti icing additive in fuel is 0.1～0.15%. It is a typical detection problem of trace substances in complex organic phase to detecting the content of only 0.1 to 0.15% of the ether substances in jet fuel comprising of by hundreds of kinds of organic matter , so there is no on-line measurement method by now. In this paper , a means is offered that combine micro extraction technology and on-line optical spectroscopy technique . by this way, anti icing additive concentration can be real-time measured and the precision can reach 5%, can meet the need of oil blending control and quality detection.

The influence of the solvent temperature and the solvent quality on the chain conformation and the aggregation of semiconducting block copolymers is described in this paper. In selective solvents for the polystyrene block, aggregation is detected by means of optical spectroscopy. The author thinks that the research is useful for the development of material engineering.

A four-ball tester was used to evaluate the tribological performances of bismuth naphthenate (BiNap), sulfurized isobutene (VSB), and their combinations. The results show that the antiwear properties of BiNap and VSB are not very visible, but they possess good extreme pressure (EP) properties, particularly sulfur containing bismuth additives. Synergistic EP properties of BiNap with various sulfur-containing additives were investigated. The results indicate that BiNap exhibits good EP synergism with sulfur-containing additives. The surface analytical tools, such as X-ray photoelectron spectrometer (XPS) scanning electron microscope (SEM) and energy dispersive X-ray (EDX), were used to investigate the topography, composition contents, and depth profile of some typical elements on the rubbing surface. Smooth topography of wear scar further confirms that the additive showed good EP capacities, and XPS and EDX analyzes indicate that tribochemical mixed protective films composed of bismuth, bismuth oxides, sulfides, and sulfates are formed on the rubbing surface, which improves the tribological properties of lubricants. In particular, a large number of bismuth atoms and bismuth sulfides play an important role in improving the EP properties of oils.