Highly-elastic state

Kuznetsov et al. s methodological approach [72-75] provides another example of attempts to evalue the interphase thickness experimentally. Their approach was based on the hypothesis that the mesophase remains glassy while the bulk of the binder has already passed to the highly elastic state. Investigating the concentration... 

The properties are evaluated at temperamres between —50°C and 250°C (high elastic state of mbber). For mbbers in a high elastic state, an increase in fullerene concentrations is followed by a rise in modulus. It is very lucid at temperatures between — 10°C and 150°C. Most likely, it is caused... 

G. V. Vinogradov, A. I. Isayev, D. A. Mustafaev, and Y. Y. Podolsky, Polarization-optical investigation of polymers in fluid and high elastic states under oscillatory deformation, J. Appl. Polym. Sci., 22,665 (1978). 

Small molecular mass liquid crystals do not respond to extension and shear stress. Liquid crystalline polymers may exhibit a high elastic state at some temperature due to the entanglements. However, the liquid crystalline network itself is an elastomer, showing rubber elasticity. In the presence of external stress, liquid crystalline networks deform remarkably and then relax back after the release of stress. The elasticity of liquid crystalline networks is more complicated than the conventional network, such as the stress induced phase transition, the discontinuous stress-strain relationship and the non-linear stress optical effect, etc. 

Remember that we are talking about a polymer in a highly elastic state. It seems a sensible assumption that its volume has not changed under the strain. Then, both the y-size and the z-size of the sample ought to have... 

Tr, the temperature at which the highly elastic state ceases to exist, has been the subject of many systematic studies Of course, it is closely related to the chemical structure of the polymers involved, although the situation is often not easily explained, see p. 660. 

Most authors do not discriminate between Tr and but consider Tg as the freezing temperature of the rubbery state. This is not exact however, because there is a transition between the rubbery clastic and the rigid state, namely the highly elastic state (elastic extensibility between 1 and 100%. 

The praetical importance and eomplexity of strueture of polymer composites with matrix, which is in high-elasticity state, are due to a large number of works, devoted to studies of structure and properties of the mentioned composites. Lipatov [1] summarized obtained... 

Mechanochemistry of highly elastic state polymers processing... 

The highly elastic state is exclusively specific to the polymers being a consequence of the linear macromolecule flexibility. 

Therefore, the mechanochemical phenomena are also present in the case of highly elastic state polymers processing even if their intensity is lower in comparison with vitreous state polymers. 

The study of the fracture process of the elastomer-based systems containing fillers evidenced that the weakest zone is the interface elastomer-particle [1191]. The fracture occurs by the destruction of the existing bonds in the contact area, especially of the adhesive bonds. In means that the material structuration by reinforcement is intensified by the increase of adhesive forces. Therefore, using black carbon as reinforcing agent, the maximal effect is achieved whenever the elastomer is in highly elastic state [1192]. Consequently, it results that the reinforcement sensibly depends on temperature [464]. 

An amorphous plastic (curve A) softens at a higher temperature than the with its viscosity continuously diminishing. The state of the plastic at temperatures above Tg is known as the high elasticity state, and in this state the plastic may be bent or vacuum-formed. When the not precisely defined flow temperature, Tp, is reached, the plastic may be extruded or injected (injection temperature, T ). Further heating of the plastic causes its thermal destruction (breakdown temperature, T ). The flow and setting temperature are not strictly defined for amorphous plastics. 

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