Thermomechanical Properties of Polymers

This article reviews recent developments in polymer thermomechanics both in theory and experiment. The first section is concerned with theories of thermomechanics of polymers both in rubbery and solid (glassy and crystalline) states with special emphasis on relationships following from the thermomechanical equations of state. In the second section, some of the methods of thermomechanical measurements are briefly described. The third section deals with the thermomechanics of molecular networks and rubberlike materials including such technically important materials as filled rubbers and block and graft copolymers. Some recent data on thermomechanical behaviour of bioelastomers are also described. In the fourth section, thermomechanics of solid polymers both in undrawn and drawn states are discussed with a special focus on the molecular and structural interpretation of thermomechanical experiments. The concluding remarks stress the progress in the understanding of the thermomechanical properties of polymers. 

Fig. 12. Thermomechanical properties of polymers from(IOJc) and (104 a) in phenol, (a) soluble polymer, (b) after heating this polymer to 500 K...

Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and infrared spectroscopy are the common techniques used in the characterization of the structure of the congealed solid. Thermal analytic methods, such as DSC and differential microcalorimetric analysis (DMA), are routinely used to determine the effect of solutes, solvents, and other additives on the thermomechanical properties of polymers such as glass transition temperature (Tg) and melting point. The X-ray diffraction method is used to detect the crystalline structure of solids. The infrared technique is powerful in detecting interactions, such as complexation, reaction, and hydrogen bonding, in both the solid and solution states. 

Mechanical and Thermomechanical Properties of Polymers Editors K.-F. Arndt, M.D. Lechner Authors W. Grellmann, S. Seidler... 

Torsion-braid analyzer n. An instrument which permits the measurement of thermomechanical properties of polymers that are undergoing structural changes during cure. Shah V (1998) Handbook of plastics testing technology. John Wiley and Sons, New York. 

Bansal A, Yang H, Li C, Benicewicz BC, Kumar SK, Schadler LS (2006) Controlling the thermomechanical properties of polymer nanocomposites by tailoring the polymer-particle interface. J Polym Sci B Polym Phys 44(20) 2944—2950... 

The recommendations are revised on a regular basis, gaps are filled, and new developments are carefully observed in order to react timely on new sdentiiic trends. Examples are the revision of the Definitions of terms relating to crystalline polymers, which is currently (2011) close to publication, and the Glossary of terms relating to thermal and thermomechanical properties of polymers, which is currently (2011) in preparation. Newly started projects are... 

Over the past few years, many attempts have been made to improve the thermomechanical properties of polymers by blending. Nonetheless, there remains a need for additional studies to widen the scope of knowledge of blending processes and the thermomechanical behavior of the related polymer blends. Although many studies have addressed the issue of creep polymers, investigations of the... 

Research is being conducted that shows that the thermomechanical properties of polymer... 

When comparing macromolecular systems with simple molecules, one may, a priori, think that the thermomechanical properties of polymers would be easier to describe since matter exists only in two physical states (solid and liquid) in the polymer case instead of three for simple molecules. Indeed, the transition from the liquid to the gaseous state does not exist for polymers because the multiplicity of their molecular interactions prevents their vaporization at temperatures lower than that of their degradation. 

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