Preparation And Tribological Properties Of New Boron-containing Lubricating Oil Additives Study

There has been an increasing interest in environment problem along with the strengthening of environmental protection consciousness of the world.In order to decrease the environmental pollution caused by traditional lubricants,more and more people are focused on the research and development of biodegradability lubricants at home and abroad.It is necessary to research and develop environmental friendly lubricants in our country.From molecular design,two series,6 kinds of additives have been designed and synthesized by using 2-thioxobenzo[d]thiazol compound as material.Another two kinds of additives were synthesized from material of BaB₄O₇.Their main chemical structures were characterized by using IR,EA,¹HNMR.Their tribological properities,sensitivity and compatibility among additives and base oils were studied by a series of texts.Specific study contents are as follows:(1)6 kinds of additives designed and synthesized.Their main chemical structures were characterized by using IR,EA,¹H NMR.(2)In this paper,we had studied their oil solubility and copper corrosion and anti-oxidation.Furthermore,the relationship worked out by this study of solubility,copper corrosion and anti-oxidation with the structure and composition of lubricants were studied.Results indicated that six kinds of additives all possesed good oil solubility,anti-copper corrosion,anti-oxidation and biodegradability.(3)The extreme-pressure,friction-reducing and anti-wear properties of rapeseed oil with MBT-1～4 and borates as additives were studied by MRS-10A four-ball test machine.The results showed that 6 kinds of additives can increase the anti-wear and extreme pressure(the P_B vable of MBT-4 reach 1270N)properties and friction coefficient decreased greatly. These additives possess good extreme pressure(especially the P_B vable of the didodecyl(2-thioxobenzo[d]thiazol-3-(2H)-yl)methyl borate reach 1270N)and anti-wear and friction-reducing performances.Friction co- efficients under the load of 490N are lower than those under 392N.(4)Their tribological mechanisms were also investigated by using XPS,SEM/EDS etc analytic instruments.And the film can prevent the direct contact of metal and metal,to reduce the metal stock abrasion.The results indicate that surfacial films mainly composed of adosorption, deposition containing Fe₂(SO₄)₃,FeS₂ and borate.(5)By analyzing the environmentally friendly lubricant demands on the lubrication mechanism and biodegradable performance,the uniform design of experiment is used for arranging multi-level and multi-factor experiments.The stepwise technique is adopted to put forward the question.The sensitivity and compatibility among additives and base oils are studied by a series of texts.The optimum formulation of I5W/40 CNG/gas line dual fuel bus engines is presented.Several experiments are made to evaluate the property of formulation by comparing with commercial oils and the biodegradability of the lubricant is investigated with the reference of the Organization for Economic Cooperation and Development standard OECD 301.The results of the bus engine oil formula of 15W/40 newly developed have good performance at high and low temperature with the fine anti-oxidant and anticorrosion.