Concrete sealers will not stop oil from staining concrete. Period. Think of it this way: penetrating sealers penetrate into the concrete where they chemically react in the pores. The surface of the concrete is left exposed so when oil gets spilled onto the surface, a sealer may slow down the movement of the oil into the pores, but the exposed concrete will stain. If you spill oil on the surface of concrete, it should be cleaned up immediately in order to prevent staining.
The three most common types of penetrating sealers are silicate concrete sealers, Silane-Siloxane water repellent sealers, and Siliconate concrete sealers. Silicate concrete sealers will increase the strength of the concrete in order to reduce deterioration caused by surface abrasion, and Silane-Siloxane and Siliconate water repellent sealers will help to reducing staining and deterioration caused by water absorption. They reduce staining by slowing down the movement of liquids through the substrate, but because they don’t leave a protective surface film, the surface is susceptible to stains.
If you want to stop oil from staining the concrete, you need to use a coating. Acrylic sealers, epoxy coatings, and urethane coatings are the best types of coatings to use to stop oil from staining the concrete. Acrylic sealers can be used to seal interior and exteiror concrete, while epoxy and urethane coatings should only be used to seal interior concrete.
- Acrylic Sealers: Acrylic sealers will provide up to 2-10 hours of protection against oil before the oil starts to eat into the acrylic sealer.
- Epoxy Coatings: Epoxy coatings provide more protection than acrylic sealers, but less than urethane.
- Urethane Coatings: Urethane coatings provide the most protection against oil when used on an interior application because they buy you the most time to clean oil that gets spilled onto the surface. Urethane coatings are commonly used on automotive repair facilities.
The best way to determine if a particular sealer or coating is appropriate for your application, is to apply it to a test area. Once fully cured, spot test the oil that may be spilled onto your surface over the sealed area. If the sealer or coating stands up to your tests, you know it is the best solution for your application. If it doesn’t stand up to your test, you may need to try a few other sealers and coatings until you find the one appropriate for your application.