ABSTRACT
Aging means that thermal resistance of the material changes during its service period, mainly because of the changes in composition of the gas contained within the closed cells of the foam. Since aging is a very slow process and occurs over many years of service, one can reduce the period of laboratory testing by measuring the aging of thin layers. This chapter reviews different laboratory procedures used for characterizing Spray Polyurethane Foam (SPF) products and determining their physical properties. The test methods are repeatable and reproducible, however, they may or may not be correlated with the SPF field performance. To establish the initial thermal resistance of the SPF product, thermal resistance tests must be performed on five to seven, specimens, and their results must be averaged. Determination of the initial thermal resistivity normally involves testing specimens cut from one to two week-old, 75-100 mm thick slabs.
