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8631519 
Book/Book Chapter 
Role of amine catalysts in CFC reduced rigid polyurethane foam systems 
Okuzono, S; Arai, S; Tamano, Y; Kumoi, S; Lowe, DW 
1993 
International Progress in Urethanes 
6 
1-23 
English 
The concerns regarding CFC usage and reduction have spread throughout the world and the initiation of the CFC reduction programs pose a serious impact on present day rigid foam technology. It seems that there are two options for the Japanese refrigerator manufacturer in order to comply with the CFC reduction policy. The first option would be to develop new formulations which increase water levels and decrease CFCs as the auxiliary blowing agent. The relative increase in water level in basic appliance formulations may, however, adversely affect many foam properties such as inferior friability, k-factor and dimensional stability. In this report, the roles of amine catalysts are discussed in high water level rigid foam systems along with the introduction of TOSOH's new Toyocat-F series of amine catalyst systems designed specifically for this changing technology. As a result, the combinations of Toyocat-F85 or Toyocat-F94 and Toyocat-DT have both proved to improve foam properties, such as good flowability, surface friability and dimensional stability compared to other amine catalysts tested. The second option for compliance to the new CFC reduction program would be to adopt newly developed HCFC alternative products, such as HCFC-141b and HCFC-123, to the `fine cell technology.' TOSOH Corporation has contributed through developing a series of specialized tertiary amine catalyst systems, such as Toyocat-B20 and Toyocat-B54, designed specifically for the fine cell polyurethane technology. In this report, these systems are discussed as to their effectiveness when HCFC alternatives are applied in the fine cell systems. Consequently, it has been proved that Toyocat-B20 and Toyocat-B54 provide not only closer reaction profiles to traditional CFC-11 blown systems, but also improved foam properties such as lower foam density, better flowability and lower k-factor in fine cell systems when HCFC alternative products were used.