Ethylene-propylene Copolymer Lubricant Viscosity Index Improver Agent

In this paper, product and technology of ethylene propylene copolymer initiated by VOCl3-l/2Al2Et3Cl3 used as lubricating oil viscosity index improver were developed because of the demand of it in the market at home, based on the structure data of Exxon-8921 and technology of EPDM introduced from abroad by JCIG Corporation.At first, the effects of initiator composition and dosage of it, dosage of activator, composition of materials, reacting temperature and reacting time on the co-polymerization were investigated, and the regulars of co-polymerization and properties of products along with variations of the factors above-mentioned were obtained. The examination results indicated: Dosage of initiator affects the yield, efficiency of initiator and [η ] of copolymer. The concentration of active center increases with the increase of dosage of initiator, so the yield of copolymer increase. The chance of chain transfer reaction and the viscosity of solution increases with the increase of dosage of initiator, so efficiency of initiator and [ η ] of copolymer decrease . Al/V can affect the co-polymerization markedly. The optimum range of Al/V is 20-40. When Al/V is out of this range, efficiency of initiator will decrease and distribution of copolymer molecular weight will become broad. Adding activator ETCA to VOC13-l/2Al2Et3Cl3 can raise efficiency of initiator greatly, at same time reduce molecular weight of copolymer. It is indicated by kinetics examination that the effect of ETCA is to raise the concentration of active center in solution then efficiency of initiator is improved and molecular weight of copolymer is lowered. Material composition can affect yield, [ ] and composition of copolymer notably. The increase of propylene content in material will lower yield and [ ] .The composition of copolymer is able to be controlled by changing propylene content in material .Hydrogen can adjust molecular weight of copolymer efficiently. Reacting temperature and reacting time are main condition factors to the co-polymerization. When reacting temperature rises the effect of declines of active center concentration and monomer concentration will be dominant, so efficiency of initiator and [ n ] of copolymer reduce. In general temperature is controlled in 0-50 . Yield increase along with reacting time .It is usually limited in 30-60 minutes.Products were analyzed by GPC, NMR and infrared spectroscopy respectively, and the result was compared with Exxon-8921.lt was indicated that the composition, molecular weight, distribution of molecular weight and distribution of molecular sequence of our product were the same as those of Exxon-8921. Simulative assess examination, bearing causticity examination (LABECOL-38) and detergency under high temperature examination (Caterpillar-1G2) have been carriedthrough together with Exxon-8921.The results of the examinations indicated the performance of our product was the same as that of Exxon-8921.According to the demand of properties of viscosity index improver , comprehensively studying various factors above-mentioned and the actual situation of the available EPDM plant, the optimum technical parameter was decided, and the plan of pilot examination was given. The results of the pilot examinations indicated that the technology we developed was feasible and the performance of our product came up to the standards of Exxon-8921.