Rigid Polyurethane Foam Systems for Intermittent Boards Blend polyols is a compound which consists of polyether polyols, foam stabilizer, catalyst, foaming agent ... retardant etc. in a special ratio. The foam has good thermal insulation property, light in weight, high compression strength ... cold stores, cabinets, portable shelters and so on. Rigid Polyurethane Foam Systems for Intermittent Boards