Synthesis And Properties Of Benzothiazole Derivatives Lubricant Additives

Traditional lubricant additives were mainly focus on satisfying the use performance of lubricating oil when designing the molecules,while less taking the environment,health and other factors into accounts,leading to their usage were increasingly restricted by environmental requirements.In addition,with the rapid development of modern industry,traditional lubricant additives are difficult to adapt to increasingly demanding working conditions.Therefore,it is very important and urgent to develop new environmentally friendly and efficient lubricating oil additives.In this paper,several environmental friendly heterocyclic derivatives as lubricant additives were designed and synthesized,and their molecular structures were characterized by 1H NMR and MALDI-TOF-MS.The thermal stability,solubility and corrosion resistance in liquid paraffin(LP)of these additives were studied.The tribological properties were systematically investigated on a four-ball machine.The surface morphology and elemental composition of the worn scars were recorded and analyzed by scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS),and the action mechanism was initially discussed.The main research contents are listed as follows.(1)Four benzothiazoleacetamide trithiocarbonate derivatives lubricant additives(2a-2d)with different alkyl chains were designed and synthesized.The results showed that the initial thermal decomposition temperatures of 2a?2d were all above 201?.The copper corrosion levels of 2a-2d were 1a.All of 2a-2d showed superior tribological properties in comparison with zinc dialkyldithiophosphate(ZDDP).The maximum non-seizure load(PB)value of oil sample with 1.0%2b was 2.3 times as large as non-added LP,the sintered load(PD)value was 58.7%higher than that of LP,the wear scar diameter was reduced by 44.6%compared with that of liquid paraffin,the friction coefficient was 24.4%lower than that of LP.(2)Four benzothiazole acetate xanthate derivative lubricant additives(3a-3d)with different alkyl chains were designed and synthesized.The results exhibited that all of the copper corrosion levels of 2aa?d were la.Their extreme pressure and anti-wear properties are similar to those of ZDDP,meanwhile,it also displayed good anti-friction properties.The PB value of oil sample with 1.0%3c was 92.2%higher than that of non-added LP.(3)Four benzothiazole triazine derivatives lubricant additives(4a?4d)with various functional groups or alkyl chain were designed and synthesized.The results suggested that the initial thermal decomposition temperatures of 4a?4d were all above 238?.The copper corrosion levels of 4a?4d were la.compound 4c and 4d not only presented excellent extreme pressure properties close to ZDDP,but also have superior anti-wear properties than that of ZDDP.The wear scar diameter of the sample with 1.0%4d was reduced by 41.3%compared to non-added LP,and the friction coefficient was reduced by 20.9%compared to LP.(4)Four bornyl benzothiazole triazine derivatives lubricant additives(5a-5d)with different alkyl chains were designed and synthesized.It showed that the initial thermal decomposition temperatures of 5a?5d were all above 214?;The copper corrosion levels of 5a?5d were 1a.5a?5d all exhibited better tribological properties than ZDDP,and the PB value of the sample with 1.0%5d was 2.3 times as large as LP,the PD value was 1.6 times as large as LP,the wear scar diameter was reduced by 39.0%compared to LP,and the friction coefficient was reduced by 22.1%compared to LP.