Table 2. Chemical structure and physicochemical properties of the base fluids tested.
| Base fluid | Mw (g mol−1) | Density (g cm−3) | Molecular formula | Abbreviation | Dipole moment (D) |
|---|---|---|---|---|---|
|
106.1 | 1.118 | C4H10O3 | DEG | 1.26 |
|
134.2 | 1.022 | C6H14O3 | DPG | 1.03 |
|
633.0 | 0.8982 | C41H76O4 | DhL4016 | 5.85 |
|
368.646 | 0.8619 | C24H48O2 | DhL4018 | 3.44 |
|
596b | 0.833 | N.A.a | PAO8 | 0.08 |
a
The molecular structure for PAO8 is given as the generic polymerized PAO structure, since the composition of each specific PAO fluid is not generally disclosed given the polymerization variability. The hydrocarbon structure of PAO8 is not determined, since PAOs are the result of the oligomerization of linear α-olefins with a variable number of C in the alkyl chain.
b
Calculated values using a gas chromatography method.32