, Ltd. Qingdao, China; QDW618) was used as the base fluid. Its basic properties
are listed in Table 1. In the table, GB/T6144 is the Chinese National Standard test methods of synthetic cutting fluids. Test methods of different properties are as follows: Figure 1 Particle size distribution of nanographite. Table 1 Basic properties of QDW618 water-based cutting fluid Property pH Foam volume V (ml) (≯) Surface tension σ (mN/m) (≯) Antirust ability t (h) Abrasion resistance f (N) (≮) Single Lamination P B P D Value 8 ~ 10 2 40 24 4 800 2300 Method GB/T6144/5.3 GB/T6144/5.4 PS-341 cell line GB/T6144/5.7 GB/T6144/5.7 GB/T3142 1. pH: immerse pH test strip into the test solution, and then contrast it with the standard strip. 2. Foam volume: pour the test solution (70 mL) into a 100-mL cylinder with a stopper. After shaking (1 min) and stewing (10 min), observe the volume of the remaining foam. 3. Surface tension: test using an interface tensiometer. 4. Antirust ability: measure by cast iron (two categories, single or lamination). learn more GB/T3142 is the Chinese National Standard test methods of lubricants (determination of load-carrying capacity). Both maximum non-seizure load (P B ) and weld load (P D ) are tested on a four-ball friction tester. Preparation of water-soluble nanographite The hydrophobicity of graphite nanoparticles is the major impediment in using nanographite as an BAY 63-2521 research buy additive
in water-based fluid to improve the lubrication performance. In order to take the lubrication advantage of nanographite to water-based fluid, surface modification is necessitated to obtain water-soluble nanographite. In this study, water-soluble nanographite was prepared through in situ emulsion polymerization using methacrylate as polymeric monomer. Prior to polymerization reaction, graphite nanoparticles were pretreated by ultrasonic dispersion. The nanographite (1.0 wt.%) was added into a water solution with sodium dodecyl benzene sulfonate (SDBS). As surfactant, SDBS could Atorvastatin favor the dispersion of graphite nanoparticles during the ultrasonic process. Ultrasonic pretreatment was carried on an ultrasonic treatment
device (Shanghai Ultrasonic Device Co., Shanghai, China; FS-250) for 10 min. The effects of ultrasonic dispersion were observed by SEM. Methacrylate was refined by vacuum distillation before being used as polymeric monomer. The refined methacrylate and the pretreated nanographite were mixed into a four-necked flask. Three of the four necks were used to connect the thermometer, stirring device, and nitrogen, respectively. The other one was left for sampling. A spot of sodium bicarbonate (0.1 wt.%) was also added into the mixture to adjust the pH. Potassium persulfate was employed as the initiator of polymerization. The reaction temperatures were set as 60°C, 70°C, and 80°C. Under each reaction temperature, the sampling time was 4, 5, and 6 h. The entire experiment was conducted under nitrogen atmosphere.