Synthesis of castor oil-based lubricant pour point depressant

Castor oil-methyl methacrylate copolymer was synthesized from castor oil (CO) and methyl methacrylate (MMA) by using azodiisobutyronitrile (AIBN) as initiator, toluene as solvent under an anhydrous and anaerobic condition. The structure of copolymer was characterized by FTIR. The relative molecular mass and its distribution of the copolymer were determined by gel permeation chromatography (GPC). The performance of its pour point depression was also evaluated. The results showed that under the conditions of m(CO):m(MMA)=1:1, AIBN dosage of 0.25% (based on the total mass of monomers, the same below), at 80℃ for 8 h, the copolymer had a yield of 59.20%, average relative molecular weight of 2.722×105 and exhibited narrow relative molecular weight distribution (PDI=1.51). When the additive amount of copolymer was 0.5% (based on the mass of oil product, the same below), the pour point of the lubricating oil could decreased by 10℃, indicating that the copolymer had a certain effect of lowering pour points (ΔSP=10℃). © 2021, Editorial Office of FINE CHEMICALS. All right reserved.