Enzymatic Synthesis of a Polyol Ester from Levulinic Acid and Trimethylolpropane and Its Tribological Behavior as Potential Biolubricant Basestock

Wenyuan Zhu; Fangyuan Liang; Hewei Hou; Yuting Chen; Xiaohui Liu; Xudong Zhu

doi:10.3390/polym12102256

Enzymatic Synthesis of a Polyol Ester from Levulinic Acid and Trimethylolpropane and Its Tribological Behavior as Potential Biolubricant Basestock

Polymers (Basel). 2020 Oct 1;12(10):2256. doi: 10.3390/polym12102256.

Authors

Wenyuan Zhu¹, Fangyuan Liang¹, Hewei Hou¹, Yuting Chen¹, Xiaohui Liu², Xudong Zhu³

Affiliations

¹ Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China.
² School of Computer Science and Technology, Qilu University of Technology (Shandong Academy of Sciences), Jinan 300175, China.
³ School of Light Industry Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 300175, China.

Abstract

In this study, a polyol ester from levulinic acid (LA) and trimethylolpropane (TMP) was synthesized by enzymatic catalysis in a solvent-free system. The total conversion of TMP reached up to 84% on average after lipase recycling for five times. The produced ester showed excellent lubrication properties, such as high viscosities at 40 °C (86.53 mm²/s) and 100 °C (8.91 mm²/s), a good viscosity index (49), a low pour point (-27 °C), and a high flash point (223 °C). The frictional wear behavior was evaluated on a four-ball test machine (FTM) by adding the ester into a reference mineral oil. The blend with 10% ester showed a smaller wear scar diameter (WSD) (0.62 mm) when compared with that of pure mineral oil (0.78 mm). The results demonstrated that the obtained ester has huge potential as biolubricant basestock.

Keywords: biolubricant; levulinic acid; polyol ester; tribological behaviors.

Abstract

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