Suprasegmental structure

Let us consider now the results of the concept [44, 45] application to polymers yielding process description. The yielding can be considered as polymer structure loss of its stability in the mechanical stresses field and the yield strain is measure of this process resistance. In Ref. [44], it is indicated that specific lifetime of suprasegmental structures t is coimected with AG as follows ... 

Hence, the presented above results have shown that elasticity modulus of amorphous glassy polycarbonate, considered as natural nanocomposite, are defined completely by its suprasegmental structure state. This state can be described quantitatively within the frameworks of the cluster model of polymers amorphous state structure and characterized by local order level. Natural nanocomposites reinforcement degree can essentially exceed analogous parameter for artificial nanocomposites [56]. 

As follows from this plot, AG (AT) dependence for the mentioned polymers corresponds, both qualitatively and quantitatively, to the data adduced in papers [46, 48, 49]. Principally, this allows calculation of the segment size, which is different for various polymers. Deviation from the plot of the data for polymers with high T indicat es the features of suprasegmental structure for these substances [46]. The data of Figures 1.6 and 1.7 indicate that the cluster model postulated in [7,13-15], based... 

Therefore, Equations 1.20 and 1.21 are fulfilled for polymers simultaneously, i.e., suprasegmental structure formation represents a non-equilibrium transition resulting in formation of non-equilibrium structures. It is significant that the beginning of their formation corresponds to the glass transition, i.e., to the transition from an equilibrium devitrified state to a weakly non-equilibrium glassy one. 

Finally, it should be noted that AG values regulating formation of suprasegmental structures in polymers are definitely connected with molecular characteristics of the latter. Since a polymer is a solid consisting of long chains of macromolecules, it should be expected that the most important (or at least one of the most important) property is the polymer chain flexibility, which can be expressed with the help of the... 

Thus the dependences AG (AT) for suprasegmental structure of polymers within the frameworks of a macrothermodynamic hierarchical model qualitatively and quantitatively correspond to previously obtained analogous correlations for a wide set of substances [46, 48, 49, 55]. This proves the reality of these structures for the polymer amorphous state. Equations 1.20 and 1.21 are equally applicable to the description of the thermodynamic behaviour of these structures and can be used for their quantitative simulation. If more strict calculations are required, corrections for heat capacity change at phase transitions must be introduced [55]. 

At present analysis of relations between molecular characteristics, supramolecular (suprasegmental) structure parameters and properties of crosslinked polymers is carried out, as a rule, on the qualitative level [27]. It is connected with the complexity of the structure of spatial networks and the quantitative structural model for absence of these polymers [93, 130]. Therefore receiving quantitative relations between the mentioned parameters is an important goal of polymer physics, which is necessary for prediction of the properties of crosslinked polymers. The authors [130] solved this problem by the application of a number of physical concepts synergetics of deformable bodies [47], fractal analysis [92, 93] and the cluster model of the amorphous state structure of polymers [5, 6]. 

The value of for the aged samples of EP-2 is larger than for native ones (Table 6.4). Analysis of the data adduced in Table 6.4 shows that in the ageing process and are changed similarly, whereas between and such an interconnection is absent. Hence, the value of does not depend directly on v, but is defined by suprasegmental structure characteristics (see, for example. Figures 6.2 and 6.3). 

Aylett, M. P. Stochastic suprasegmentals Relationships between redundancy, prosodic structure and care of articulation in spontaneous speech. In Proceedings of the International Conference on Speech and Language Processing 2000 (2000). 

The Gibbs function of suprasegmental (cluster) structure self-assembly at temperature T=T - AT was calculated as follows [45] ... 

Hence, the stated results demonstrated undoubted profit of fractal analysis application for polymer structure analytical description on molecular, topological and supramolecular (suprasegmental) levels. These results correspond completely to the made earlier assumptions (e.g., in Ref [31]), but the offered treatment allows precise qualitative personification of slowing down of the chain in polymers in glassy state causes [32]. 

Hence, the stated above results demonstrated that neither eross-linking degree nor molecular orientation level defined cross-linked polymers final properties. The factor, controlling properties is a state of suprasegmental (nanocluster) structure, which, in its turn, can be goal-directly regulated by molecular orientation and thermal treatment application [62]. 

The combined use of fractal analysis and cluster models for the structure of the condensed state of crosslinked polymers allows their quantitative treatment on different structural levels, molecular, topological and suprasegmental, to be obtained for the first time and also the interconnection between the indicated levels to be determined. In turn, elaboration of solid-phase crosslinked polymer structure quantitative models allows structure-properties relationships to be obtained for the first time, which is one of the main goals of polymer physics. 

Let us show how the value of (i.e., at the molecular and topological levels) influences the suprasegmental level of the structure. Within the frameworks of the cluster model [5,6] the number of densely packed segments in clusters per volume unit is approximately equal to the cluster network density and is connected with v by Equation 2.7, in which the numerical constant accounts for the necessary molecular constants of polymers. 

Therefore, the results stated above testify that the suprasegmental (cluster) structure of crosslinked polymers obeys the general laws of fractal geometry and defines the properties of the indicated polymers. Let us note that the value is again a function... 

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