Polyol is the B-side of a two-component polyurethane system, the resin blend that reacts with isocyanate to create the expanding foam used to lift and stabilize concrete.
In depth
The polyol side is where a foam gets its personality. Blended with catalysts, surfactants, and blowing agents, the B-side formulation determines how fast the foam reacts, how much it expands, its final density, and whether it is hydrophobic.
Different formulations produce different foams for different jobs, from high-density structural lifting foam to deeper soil-stabilization foam. The B-side chemistry is a big part of what separates purpose-built concrete raising foam from generic spray foam.
How Acme applies it. We match the foam formulation to the job, whether that is lifting a garage floor, filling voids under a stoop, or stabilizing deeper soil layers before a lift.
Related terms: Two-Component Polymer, Hydrophobic Foam, High-Density Foam, Foam Density
Frequently asked questions
What is the difference between the A-side and B-side?
The A-side, isocyanate, is the reactive component. The B-side, the polyol blend, is the formulated resin that controls the foam\u2019s expansion, density, and cure behavior. Both are required, and neither works alone.
Do all contractors use the same foam?
No. Foams vary widely in density and quality. Ask any contractor what density their foam is and whether it is hydrophobic before hiring.