Preparation and evaluation of some newly liquid crystal as antioxidant for base stocks

Authors

  • Ashraf Ashmawy Chemistry Department, Faculty of Science (boys), AL-Azhar University, 11884, (EGYPT).
  • Doaa Osman Egyptian Petroleum Research Institute, Evaluation and Analysis Department.
  • El Sayed Elnaggar Chemistry Department, Faculty of Science (boys), AL-Azhar University, 11884, (EGYPT).
  • Maher Nessim Egyptian Petroleum Research Institute, Evaluation and Analysis Department.
Abstract:

Four liquid crystal compounds of the form, 2-Sec-butyl-4-[(4-x-phenyl) diazenyl) phenyl-4-(octadecyloxy] benzoate symbolized as I18a, I18b, I18c and I18d were prepared in which the substituent (X) was taken CH3O-, CH3-, Br- and -NO2 respectively. Characterization of prepared compounds is done using FT-IR, 1H-NMR, Mass Spectroscopy and Elemental Analysis.. Their mesophase behavior was investigated by Differential Scanning Calorimetry (DSC). Their antioxidant efficiency for Egyptian lubricating base oil was tested. The oxidation processes was monitored using the change in the Total Acid Number (TAN). The obtained results showed that, the efficiency of these compounds was ranked as follows I18d > I18c > I18b > I18a.

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Journal title

volume 6  issue Issue 4, pp. 325-460

pages  369- 379

publication date 2018-10-01

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