Flexible Dielectric urethane foam

Im trying to build a flexible sensor array and I need to find some flexible dielectric foam , with densities of 2 lbs/ft^3 or less ( or, 15 kg/m^3 and 30 kg/m^3). I need 2 different densities of foam to detect 2 levels of deformation.

I have had difficulty finding commercial suppliers , especially those who are willing to do business with a University student.

If there are alternatives, please enlighten me.

Thank You.