RESUMO
Herein, we report the synthesis, characterization, and biological properties of eleven (3a-3k) novel Schiff bases. The spectral data of FT-IR, 1H NMR, 13C NMR, and LC-MS are associated with these synthesized compounds. From the FT-IR analysis, we confirmed the azomethine (-C=N-) group and from 1H NMR data, the phenolic -OH proton is appeared at range δ 13.92-14.09ppm due to hydrogen bonding. The LC-MS analysis agreed with molecular ion peaks of synthesized Schiff bases. To evaluate the antibacterial activity of newly synthesized compounds were screened against b. licheniformis, b. species, e. coli, and s. aureus. Furthermore, the antioxidant activity was investigated by two methods 2,2-diphenyl-1-picryl hydrazyl (DPPH) and hydroxyl radical scavenging methods. The (-NO2,-Cl,-Br,-I) substituted compounds have shown good antibacterial activity against tested organisms. Also, these compounds were exhibited higher antioxidant activity by given methods.
RESUMO
Nanocomposite made by blending nano-montmorillonite (MMT) and Silicon Rubber (SR) for mechanical and tribological performance is explored in this work. Different configurations of MMT/SR nanocomposite, with 0, 0.5, 2 and 5 wt % of MMT are manufactured by two roll mixing methods. Noticeable improvement in the mechanical and tribological performance is observed, which is also justified by a morphological study of fractured and wear surfaces through SEM. Two percent of MMT loading is found to be the optimum content that shows excellent performance compared to other compositions. The performance improvement can be linked to the good interfacial interaction between the MMT and SR. Statistical modeling through ANOVA is carried out for tribological performance, which reveals the influence of load on the coefficient of friction (COF) and the influence of sliding distance on the wear rate.
