Foam products are manufactured with chemical blowing agents that expand the plastic matrix before it solidifies. The type and amount of blowing agent used, as well as the processing conditions applied, determines the final density of the foam that is generated. Since HCFCs are commonly used as blowing agents, foam manufacturing is the second largest consumption sector worldwide for those substances. The main applications of HCFC blowing agents is in rigid polyurethane (PU) foam used in sandwich panels, pipe and appliance insulation, in spray foams and in extruded polystyrene (XPS) foam. Common blowing agent formulations found in developing countries use HCFC-containing pre-blended polyols that are imported from other countries.
HCFCs are being phased out under the Montreal Protocol. With assistance from the Multilateral Fund, developing countries are encouraged through their HCFC Phase out Management Plans (HPMPs) to prioritize the phase out of substances with high ozone depleting potential (ODP) first. Such high-ODP substances are mainly used in the foam sector. The transition to non-HCFC blowing agents requires the adoption of alternative technology by industry, along with the development of appropriate policies, licensing and quota systems, and import controls of pre-blended polyols.
A wide range of alternatives to HCFCs are available, including hydrocarbon technology, modified water blown formulations, supercritical carbon dioxide, methyl formate, methylal, HFOs, and high-GWP HFCs. The selection of the most appropriate alternative technology requires consideration of many factors including the long term competitiveness, safety, cost, training, and availability.
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