[Yoritomo]

Hello!

    How do I dissolve polyurethane foam (insulation spray)?

     I mean dissolving the cured (solid) foam.

     Thank you!
            -Kostas.

[Enthalpy]

Hi Kostas,

Foams are destroyed more quickly than plain polymers, but by the same compounds, so what you need is the compatibility of polyurethane (search keywords). Examples:
https://www.spilltech.com/wcsstore/SpillTechUSCatalogAssetStore/Attachment/documents/ccg/POLYURETHANE.pdf
https://www.engineeringtoolbox.com/polyurethane-chemical-resistance-d_1878.html
http://cdn.norgren.com/pdf/Chem%20Resis%20Man.pdf
https://www.hooverferguson.com/media/wysiwyg/docs/reference/Polyethylene-Compatibility-Guide.pdf?direct=true
essentially, PU is degraded by acids, bases, oxidisers, ketones, alcohols and many more. Acetone would be my first candidate, but this depends also on the materials you want to keep.

Please be careful with explosive or toxic vapours, etc etc.