Synthesis Of Diene/Styrene Copolymers And Their Application Performance

The star-structured polymer has the advantages of simple design,novel structure and unique performance.It is a kind of high-performance polymer with excellent application prospects.Star polymers have a lower intrinsic viscosity and a smaller hydrodynamic volume due to their unique branched structure compared to linear polymers of the same molecular weight.After years of research and development,star polymers have made achievements in many fields such as drug carriers,nanomaterials,and papermaking industry because of their unique molecular structure and branching properties.Viscosity Index Improvers(Viscosity Index Improvers),as the third largest additive in advanced lubricants,play an important role in improving the viscosity and temperature performance of lubricants,reducing engine wear and energy conservation and emission reduction.Hydrogenated styrene-diene(HSD)-based viscous fingering agents are excellent products of a class of viscous fingering agents with the advantages of strong viscosityenhancing ability,excellent low-temperature pumpability,and strong shear stability.However,due to the complicated production process of HSD adhesives,most of the related patents are currently owned by foreign companies.There is no technology or patent for related products in the country in recent years.Therefore,the synthesis and performance evaluation of these polymers are relevant to domestic Technical requirements have important guiding significance.(1)In this paper,the polymer structure is designed based on the method of living anionic polymerization.Butadiene,isoprene,styrene and myrcene are the monomers,and diphenylethylene(DVB)is the coupling agent in cyclohexane solution.Polymerization was initiated with n-BuLi as initiator to prepare a diene/styrene star structure polymer.The characterization results show that a series of diene/styrene star polymers with different structural compositions were successfully synthesized through the regulation of monomer composition,block composition and coupling reaction.(2)The hydrogenation reaction was studied using a diene/styrene star polymer with excellent coupling effect as the base polymer.Subsequent use of 150 N of CNOOC II product as the base oil,using commercially available HSD-based adhesive SV260 as the reference sample,evaluated the application performance of the viscous fingering agent for the polymer that had an excellent hydrogenation effect.The results showed that the prepared hydrogenated diene/styrene copolymers all reached the reference polymer level in the viscosity index(VI)performance index.Hydrogenated ethylene/propylene/styrene copolymer with a basic polymer monomer/material ratio of Bd/Ip/St of 38.7/57.4/3.9 is relatively optimal,with a viscosity index(VI),a thickening ability(T),and a shear stability index(SSI).Both are comparable to the reference viscometer SV260 product.