Why do pin-holes emerge in polyurethane foam?

Tamilarasan Palanisamy @Tamilarasan-Palanisamy

07 March 2014 1 8K Report

I prepared polyurethane foam in batch method. I found some pin-holes in the foam cubes. But it was not in the continuous foaming method.

Sajid Iqbal

It is probably due to small air bubbles that are trapped in the highly viscous resin (polyol) during mixing.

These can be avoided by changing the mixing technique, increasing pressure on the mixing vessel, or by adding some additives etc.

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