A peroxide-decomposing antioxidant

Organomolybdenum is an important peroxide decomposing antioxidant, which can also effectively reduce the friction factor of oil. For example, molybdenum diisooctyl dithiophosphate is a lubricating oil additive with good oil solubility and remarkable anti-friction and anti-wear effect. It is the main component of the running in oil for the high efficiency internal combustion engine. It can also be used in gear oil, hydraulic oil, crankcase oil and metalworking oil to reduce friction and wear. In recent years, fuel economy has become an international hot issue, reducing friction and improving antioxidant performance are obviously reflected in the new generation of oil specifications in Europe and the United States. For example, molybdenum carbamate antioxidant has excellent anti-friction performance, which can help the internal combustion engine oil pass the energy-saving bench test of new specifications; Molybdenum ammonia complex has good antioxidant performance and excellent anti-friction performance. Shigeki Matsui et al used long chain alkyl molybdenum ammonia complex 0.02% (measured by molybdenum mass fraction) to make a kind of lubricating oil with low friction factor, small grinding spot diameter and very good cleanness. This fully formulated ammonia-molybdate complex lubricating oil was assessed to have a cleanliness of 10 points (i.e., full score) under 1.5% soot conditions.

Some researchers have also introduced a kind of molybdenum ammonia complex with excellent anti-friction performance, which has a lower friction factor than molybdenum dialdehyde dithiocarbamate in oil products, and some people add it to fuel oil to improve the oxidation resistance and storage stability of fuel oil. Alkyl thiocarbamate compounds used as lubricant antioxidants mainly include zinc dialkyl dithiocarbamate, molybdenum dialkyl dithiocarbamate, antimony dialkyl dithiocarbamate and cadmium dialkyl dithiocarbamate. For example, zinc dialdehyde dithiocarbamate is a multi - effect additive, especially in high temperature. Copper dialdehyde dithiocarbamate has not only good high temperature oxidation resistance, but also good antifriction and corrosion resistance. In addition, metallized dialkyl dithiocarbonate is also an important peroxidation-free decomposition antioxidant. It has a good compound effect with phenolic free radical scavenger and amine antioxidant, which can effectively inhibit the viscosity increase caused by high-temperature oxidation of oil products and control the formation of oil sludge. Alkyl dithiocarbamate has strong synergistic effect when used together with many additives, which can improve the efficiency of other additives and is not easy to lose its activity under high temperature. At the same time, it has a good extreme pressure effect at a higher content, which can partially replace ZDDP. The mass fraction of antioxidant was 0.1% ~ 1.0%. The mass fraction used as extreme pressure agent was 2.0% ~ 4.0%. Mainly used in turbine oil, hydraulic oil, gear oil and internal combustion engine oil, can improve the oxidation resistance and wear resistance of oil products; Increased Timken OK load in grease.