Borate Esters as used in Amsoil etc. ie: Certified Oils:
Borate Esters are used in engine oils to improve performance and protect against damage. They:
- Reduce friction: Borate esters reduce friction in engine oils, which can help the engine run more efficiently.
- Prevent sludge: Borate esters prevent sludge from forming in engine oils.
- Improve lubrication: Borate esters improve lubrication properties in engine oils.
- Extend oil life: Borate esters can extend the service life of engine oil and delay maintenance.
- Improve thermal stability: Borate esters provide thermal oxidative stability.
- Improve pumpability: Borate esters ensure low sludge formation and pumpability at low temperatures.
- Improve anticorrosion: Borate esters provide anticorrosion at high temperatures.
Here's the formula:
Boric Acid + Alcohol = Borate Ester + Water
B(OH)₃ + 3 ROH → B(OR)₃ + 3 H₂O
NB
That the reaction does not only go one way.
Any water in the oil and:
Water + Borate Ester = Boric Acid + Acohol
That means that just about everyone already has a tiny amount of Boric Acid in their engines, with no ill effects as far as reacting with the rest of the additive package in the oil goes.