Session 4 on foaming polyurethanes will include the following presentations: "HFC blowing
agents for rigid insulation foams," Lotbar Zipfel and Christoph Meurer, Solvay Fluor, Germany; "Recent developments in the use of HFC-245fa blowing
agent for rigid polyurethane foam," Saskia Walraedt, Honeywell, Belgium; "New developments in applications of methylal as blowing
agent for rigid, flexible, integral skin and microcellular polyurethane foams," Michel Beaujean, Lambiotte & Cie, S.A., Belgium; "Pentane spray system: An effective and safe technology," Claudio Chittolini and Valentina Robles, Ediltec Srl, Italy; and "Cell structure and thermal conductivity of rigid polyurethane foams blown with cyclopentane in different molds," Aleksander Prociak, Cracow University of Technology, Poland.
Wyeth's process, which was patented May 15, 1973, involved molding a PET preform and then reheating, stretching, and blowing
it into a bottle.