Basic Methodology of Controlled Pore Size Flexible Slab Stock Polyurethane Foam Manufacture
Cushman Engineering Technical Paper presented to the PFA November 5, 2014
Basic Methodology of Controlled Pore Size Flexible Slab Stock Polyurethane Foam Manufacture
Abstract: Flexible polyurethane foams for technical applications with tight performance specifications manufactured for further processing (e.g.: chemical or thermal reticulation) require uniformly controlled pore size. Basic elements of pore size control are addressed. These elements are largely the relationship of processing parameters such as pressure, temperature, dissolved gas and mixing shear to resultant pore size. The effect of adjusting each of these control parameters is examined. An emphasis is placed on controlling dissolved gas level in the isocyanate stream and polyol stream. Examples of equipment configurations required to obtain good pore size control are discussed and illustrated with piping schematics and equipment diagrams.