New Additive Solutions for Rigid Polyurethane and Polyisocyanurate Lamination Foams

ABSTRACT Rigid foam technology is the most dynamic segment of polyurethane chemistry today as this application area has been affected most by the blowing agent changes of the last few years. Alternative blowing agent technologies for rigid foam have been implemented over the last couple of years and have resulted in numerous processing and performance issues. These issues must be resolved in order to stay competitive with other insulating materials. Aliphatic hydrocarbons such as n- and iso pentane are commonly used as physical blowing agents in the European rigid foam industry. The Asian region also uses pentane blowing agents and in addition interest is seriously increasing in North America for rigid lamination applications. In order to overcome the issues related to the introduction of these new technologies, formulations have to be significantly modified and even fundamental changes, such as conversion from classical polyether based PUR to polyester based polyisocyanurate are currently under consideration if not already practised. After polyols, additives play the most important role in determining the success of these blowing agent changes. In this paper we will give a comprehensive overview of the available additive options for rigid lamination applications consisting of catalysts for PUR/PIR reactions and a new pentane compatibiliser/ emulsifier technology. Proper choice of additives can address various issues resulting from the use of hydrocarbon based blowing agents and those associated with PIR/PUR technology. In this paper we will address two important issues of these technology changes: • the impact of catalysts on the fire performance of rigid foams, • new additive solutions to allow for higher pentane use levels in rigid foam formulations.