New Insight into the Relationship Between Molecular Effects and the Rheological Behavior of Polymer-Thickened Lubricants Under High Pressure
New Insight into the Relationship Between Molecular Effects and the Rheological Behavior of Polymer-Thickened Lubricants Under High Pressure
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对分子效应与高压下聚合物增稠润滑剂流变行为之间关系的新见解
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
Philippe Vergne
中科院分区：
文献类型：
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作者：
C. Mary;D. Philippon;Lionel Lafarge;D. Laurent;Francis Rondelez;S. Bair;Philippe Vergne
研究了温度、压力和剪切应力对简化汽车润滑油（聚合物增稠基础油溶液）粘度的影响。在加氢裂化矿物基础油中以低浓度 (1.2% w/w) 使用具有不同分子量和构象（梳形、线性和星形）的各种聚合物：聚（甲基丙烯酸烷基酯）、烯烃共聚物和聚（异戊二烯-苯乙烯氢化）。他们的流变行为通过 Vogel-Tamman 和 Fulcher 方程、改进的 Williams-Landel-Ferry-Yasutomi 关系和 Carreau-Yasuda 类公式进行研究和建模。然后，爱因斯坦定律被用来快速、简单地确定聚合物的流体动力学半径作为温度和压力的函数。弗洛里方程、特性粘度和直接测量的计算证实了该方法的相关性。最后，分子因素可以更好地理解聚合物溶液的流变响应。
The effects of temperature, pressure and shear stress on the viscosity of simplified automotive lubricants—polymer-thickened base oil solutions—were investigated. Various polymers—with different molecular weights and conformations (comb, linear and star)—were used at low concentration (1.2 % w/w) in a hydrocracked mineral base oil: a poly(alkylmethacrylate), an olefin copolymer and a poly(isoprene-styrene hydrogenated). Their rheological behavior was studied and modeled with a Vogel-Tamman and Fulcher equation, a modified Williams-Landel-Ferry-Yasutomi relationship and a Carreau-Yasuda-like formula. Then, the Einstein’s law was used to rapidly and simply determine the hydrodynamic radii of polymers as a function of temperature and pressure. Calculations from Flory equations, intrinsic viscosities and direct measurements confirmed the relevance of this methodology. Finally, molecular considerations allowed a good understanding of the rheological response of polymer solutions.