Workers racing to turn reflecting pool blue for Trump may be at risk, union warns

[lonely bird]

4. Hmmm

They better be using an aliphatic polyurea. The mix ratio on the heated plural component spray rig better be correct. Since this is pigmented if agitation of the polyol side (“B”) is required by the manufacturer then that needs to be done. Coating concrete is a pain in the ass. Since this structure has been soaking in water for decades then I would recommend using a moisture tolerant primer instead of trying to coat directly over concrete. Also, concrete is porous and prone to outgassing when coated. Coating when the temperature is dropping but still over the dew point is a good idea.

Many polyureas have set times as fast as a few seconds. It is important to be certain mix ratios are correct because variance can impact the performance of the film. Aliphatic polyureas are generally much more UV stable which means that they resist color change under exposure to UV light such as sunlight. Aromatic systems will show color change under exposure to UV. The color change is usually yellowing. Also UV can damage the surface of the film.