Isocyanate is the A-side of a two-component polyurethane system, one of the two liquid chemicals that react beneath a slab to form the expanding structural foam used in concrete raising.
In depth
Polyurethane foam does not exist until the moment of injection. Two liquids, the isocyanate A-side and the polyol B-side, are kept separate in the rig and combine at the injection gun. The reaction is exothermic, meaning it generates heat, and produces a rapidly expanding foam that fills voids and lifts the slab.
Once fully reacted, the isocyanate is locked into an inert, stable polymer. The cured foam is chemically neutral, water-resistant, and does not leach into the surrounding soil.
How Acme applies it. Our rigs heat and meter the A-side and B-side precisely, because correct ratio and temperature are what produce foam with the right density and expansion. That process control is a big part of why professional equipment outperforms DIY foam kits.
Related terms: Two-Component Polymer, Polyurethane Foam, Expansion Ratio, Foam Density
Frequently asked questions
Is isocyanate dangerous under my slab?
In its reacted, cured form, which is what stays under your slab, polyurethane is inert and stable. Handling precautions apply to the liquid components, which is our crew\u2019s job, not yours.
Why does the foam need two components?
The lift comes from the chemical reaction between the A-side and B-side. Keeping them separate until injection lets us control exactly when and where the foam expands.