Volume-temperature diagram

Figure 1.28 Schematic volume-temperature diagram for a liquid crystalline polymer [66],...

For polymers which, on heating, yield Mesophases (liquid crystal melts), the so-called mesogenic polymers or liquid crystal polymers (LCPs), the situation of phase transitions is much more complex. In this case the simple Volume-Temperature diagram, given in Fig. 4.2 is not valid anymore and has to be substituted by a more complicated one, which is shown in Fig. 6.12. 

FIG. 6.12 Schematic volume-temperature diagram of a liquid crystal polymer (after Finkelmann and Rehage (1984) Courtesy Springer-verlag). 

Ammonia Equilibrium. In school experiments, it is possible to quantitatively decompose ammonia gas with the help of a nickel catalyst into its components. From 50 ml ammonia, we can get 100 ml gas, namely 25 ml nitrogen and 75 ml hydrogen (see E6.7). However, it is not possible to reverse the procedure under normal pressure, i.e. to achieve the ammonia synthesis from the elements. The volume-temperature diagram (see Fig. 6.10) confirms this one does not get any noticeable traces of ammonia at a pressure of 1 bar. In contrast, ammonia can almost be completely produced from the deployed gases at 200°C and a pressure of 1000 bar ... 

It is used to describe the glass transition. We illustrate the glass transition by an isobaric volume-temperature diagram as given in Figure 11 in chapter 5 V = V P,T) symbolizes the specific volume, V= vim. The diagram reveals ... 

Fig. 17. Volume temperature diagram illu rating the freezing process in polystyrene from the melt to the glassy state [Ret (15/)] (Symbols conf uratioiial parameter under normal cmditions rtf fnessure and cooling rate) configurational parameter at equilibrium 7 = lim T specific volume expansion...

Fig. 2.7 Pressure-volume-temperature diagram for linear polyethylene (Marlex-50). (From Matsuoka (9))...

Figure 3.4 Sample PVT (pressure - specific volume - temperature) diagrams...

Figure 5.19 Schematic volume-temperature diagram of amorphous polymer showing the temperature dependence of the free volume.

FIGURE 5.1 The volume-temperature diagram. (After A. K. Varshneya, Fundamentals of Inorganic Glasses, Fig. 2-1, p. 15, Academic Press, 19. )... 

Fig. 5.13 Volume temperature diagrams for the selenium glasses cooled at different rates (Mauro and coworkers 2009a, b)...

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