Multifunctional Tunable Polymethacrylates for Enhanced Shear Stability and Wear Prevention
- BATTELLE (PACIFIC NW LAB)
- Argonne National Laboratory
This paper describes the design, synthesis and characterization of linear, polar and non-polar polymethacrylates tuned for use as viscosity index improvers with enhanced shear and anti-wear resistance. The polymers were prepared via Reversible Addition-Fragmentation Chain Transfer (RAFT) to obtain relatively low, narrow, molecular weights, with random polar moieties. The resulting polymers were evaluated with respect to their rheology to determine their viscosity index and shear stability performance, and antiwear characteristics. The polymers had molecular weights (Mw) ranging from 120-170 kDa, and the resulting viscosity indexes (VIs) in general tracked the Mw. Although the VIs were modest (140-189), all polymers displayed higher values than a commercial product designed for similar applications, both at 2% (w/w) and when kinematic viscosities (KVs) were normalized to the lowest KV100 of ~5cSt. One of the imidazole-containing polymers displayed an anomalously high VI for a low apparent Mw. As hypothesized, many of the polar polymers demonstrated substantial wear reduction compared to the non-polar homopolymers or a commercial benchmark. The low molecular weight imidazole-containing polymer displays as much as 30x less wear than the commercial standard, followed by the higher molecular weight polymers containing imidazole, hydroxy group and amino group respectively. The strategy demonstrated the benefit of low, narrow, molecular weight polymers to achieve good shear stability in viscosity modifiers while minimizing wear, rendering them suitable for fluid-power applications.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1638922
- Report Number(s):
- PNNL-SA-152389
- Journal Information:
- ACS Applied Materials & Interfaces, Vol. 2, Issue 7
- Country of Publication:
- United States
- Language:
- English
Similar Records
Low Molecular Weight Polymethacrylates as Multi-Functional Lubricant Additives
Low Molecular Weight Polymethacrylates as Multi-Functional Lubricant Additives