Polyurethane insulation materials have reappeared. Is the conclusion too biased?

currently, polystyrene board (eps), extruded board (xps), polyurethane rigid foam (pu) three organic materials. among them, pu is currently recognized as the best thermal insulation material in the world. its thermal conductivity is the lowest among all thermal insulation materials and it has the most superior thermal performance. when the density of rigid polyurethane is…