Thermoviscoelastic behavior

Despite this large volume of results, there are almost no papers on the thermoviscoelastic behavior of PLCs and their blends with EPs under conditions of creep or stress relaxation. At the same time, it is known that the time dependence of the mechanical behavior of these materials is significant, i.e. they are distinctly viscoelastic. Thus creep and stress relaxation studies can give important information for better understanding of the peculiarities of this type of polymer material and for the application conditions of PLCs as engineering materials. 

The above-mentioned thermomechanical models only consider the elastic behavior of materials. Boyd et al. [13] reported on compression creep rapture tests performed on unidirectional laminates of E-glass/vinylester composites subjected to a combined compressive load and one-sided heating. Models were developed to describe the thermoviscoelasticity of the material as a function of time and temperature. In their work, the temperature-dependent mechanical properties were determined by fitting the Ramberg-Osgood equations and the temperature profiles were estimated by a transient 2D thermal analysis in ANSYS 9.0. 

Based on this understanding, a mechanism based constitutive model incorporating the nonlinear structural relaxation model into the continuum finite-deformation thermoviscoelastic framework was developed as follows. The aim of this effort was to estabUsh a quantitative understanding of the shape memory behavior of the thermally responsive thermoset SMP programmed at temperamres below Tg. To simplify the formulation, several basic assumptions were made in this study ... 

O Connell PA, McKenna GB (2005) Rheological measurements of the thermoviscoelastic response of ultrathin polymer films. Science 307 1760 O Connell PA, Hutcheson SA, McKenna GB (2008) Creep behavior of ultra-thin polymer films. J Polym Sci B 46 1952... 

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