Acrylic vs. Impregnating Sealer
There are 2 kinds of sealer: film-forming (often acrylic) and impregnating.
Acrylic (and other film-forming) sealers tend to be inexpensive, effective, and enhance color. They require replacement every 2-12 years depending on quality, use, moisture transmission of the concrete slab, and UV exposure. Floors sealed with acrylic become richer in color because the resin fills the pores showing the true colors of the concrete. These sealers make the concrete less skid resistant, though that can be mitigated with additives like Shark-Grit.
Impregnating sealers are more expensive but often last longer and age more gracefully. Some make concrete dramatically more stain resistant than others. Most do not change the appearance of the concrete much. They do not affect skid resistance. Some cannot be removed without very aggressive grinding.