If this was injection moulding I'd quickly say "injection pressure x developed area in mould tool x "factor"" where the "factor" is a figure that you would know from other tools that you are running.
If you are putting a foaming urethane mixture into a sandwich, then it would very strongly depend on the amount of excess material that is available and the cure forces that would exert.
Suggest that you contact the material supplier for their expert opinion and advice. They should be able to advise you of developed force per unit area and then you can extrapolate for your sheets.
Otherwise, conduct an experiment yourself making a small sample sheet and measure the force exerted.
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Just an Engineer from the land down under.
Pressure Exerted
Re: Pressure Exerted
