Influence of service temperature on shear creep behaviour of a rigid low-density closed-cell PIR foam

摘要

An experimental campaign was carried out to assess shear creep behaviour of a rigid low-density closed cell polyisocyanurate (PIR) foam. Two service temperature values were considered, 20 degrees C and 30 degrees C, and the applied stresses ranged between 20% and 60% of the corresponding shear strength. The results showed that a stress amplitude of 30% was enough to cause nonlinear creep response. Furthermore, creep deformations were slightly smaller in the tests at 30 degrees C, a fact that matched the viscoelastic response of the PIR foam obtained from DMA testing. Finally, creep prediction curves were calibrated through an analytical approach based on the Findley's power law. (C) 2019 Elsevier Ltd. All rights reserved.