Nature’s Antifreeze in Concrete

Abstract

Concrete is a porous  material that allow water to penetrate into it, which will undergo “freeze-thaw cycles” at places which experience large temperature swings, eventually popping the surface of the concrete off. To reduce freeze-thaw damage in cementitious materials, air entraining admixtures (AEAs) have been utilised. But the entrained air gaps weaken and increase the permeability of concrete, rendering it prone to various types of in situ deterioration.

Researchers in Colorado incorporated antifreezing polymer molecules into concrete, inspired by animals that survive in subzero temperatures. It is described as a soluble biomimetic antifreeze polymer with Ice Recrystallization Inhibition (IRI) and Dynamic Ice Shaping (DIS) properties that can inhibit ice crystal development damage in concrete and cement paste. In high-pH environments typical of concrete pore solution, the polyethylene glycol-graft-polyvinyl alcohol (PEG-PVA) polymer replicates the explicit IRI and DIS activity of natural ice-binding proteins. It reduces freeze-thaw damage and boosts concrete strength and durability, extending the life of new infrastructure and lowering carbon emissions during its lifetime.