No abstract

In this article, simple viscoelastic and empirical models are presented to predict and analyze the flexural creep behavior of all‐poly(propylene) (all‐PP) composites. Results of the successful application of these models to the actual creep behavior of unidirectional (UD) and cross‐ply (CP) all‐PP composites tested by short‐term flexural creep measurements over a temperature range of 20–80°C are presented. Analysis of the momentary creep behavior of all‐PP composites with different tape lay‐ups are made to understand their deformation mechanism. Further to the main theme of the article, an interesting discrepancy while predicting the long‐term creep behavior of these composites based on the time‐temperature superposition (TTS) principle and Findley power law model is visualized which has also been illustrated here. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

No abstract

The long‐term viscoelastic behavior of reinforced all‐poly(propylene) composites was studied by flexural creep tests. Both unidirectional and cross‐ply laminates were prepared from PURE® coextruded tapes by vacuum bag molding in an autoclave. The specimens were subjected to isothermal creep tests at different temperatures ranging from 20 to 80 °C under an applied load. The time‐temperature superposition principle was verified for the creep data. An Arrhenius type relationship was found to better describe the shift data obtained from the creep tests. The activation energies relating to the different reinforcement architecture and different relaxation process were calculated.magnified image