黏度指数改进剂HSD的增粘机理

Tackifiying Mechanism of the HSD Viscosity Index Improver

对聚苯乙烯-氢化聚二烯嵌段共聚物(HSD)改性的150SN润滑基础油的性能进行了测试。研究表明HSD具有优异的增粘能力和抗剪切稳定性。动态激光光散射实验表明HSD在溶液中是以胶束形式存在,胶束的流体力学半径(Rh)对温度有依赖性。温度升高,HSD的流体力学半径逐渐增大,在45℃左右,流体力学半径突然减小。实验发现不同的溶剂有不同的转变温度,但变化趋势基本相同。动态流变测试表明随着频率的增加,加入HSD的基础油的弹性模量和损耗模量均增加。在低频时主要表现为弹性效应,高频时则主要表现为粘性效应。随着温度的升高,润滑油的损耗模量逐渐减小,其弹性模量在60℃左右有一个转折点。

the properties of 150SN base oil added hydrogenated styrene-diene copolymer （HSD） viscosity index improver was tested. Result shows that HSD has excellent tackifiying ability and shear stability. Dynamic light scattering experiment shows that there are micelles in solution. With the temperature increasing, the hydrodynamic radius of micelle increase. At 45 ℃, the hydrodynamic radius suddenly reduces. Although different solutions have different turning point, the tendency is identical. There is an optimal solution temperature. Dynamic rheological tests show that as the frequency increases, the elastic modulus and loss modulus of HSD in base oil increase gradually. It mainly shows elastic effect at low-frequency but viscous effect at high-frequency. With increasing temperature the loss modulus decreases, the elastic modulus has a turning point about at 60℃.