Phase inversion temperature, definition

Kinloch and Hunston [163, 167] and others used the concept of time-temperature superpositioning, and separated the effect of changing the volume fraction and the properties of the matrix phase. No definite relationship between fracture energy and volume fraction of rubber was observed. The maximal value of volume fraction that can be achieved is about 0.2-0.3. Attempts to produce higher volume fraction result in phase inversion and loss of mechanical fracture properties. Though in most of the studies [168, 169], phase inversion was reported at a volume fraction >20%, in some recent studies inversion has been reported [170,171] at a very low volume fraction ( 2%) of rubber. 

The described experimental environment can be summarized as a 1 1 ratio of both phases, the choice of a graduated cylinder, room temperature, five-time inversion of the cylinder in a gentle or a vigorous manner, and the Earth s gravitational field. This should be only considered as an example of measuring the settling time, but what is important is to remain with a single definition in order to then use the resultant values in a comparative way. 

Figure 2.5 shows also the concentration dependence of the inverse Kauzmann temperature T (entropy catastrophe temperature). For the pure metal, T is much higher than the temperature T0 as discussed. The 77-line should also decrease with increasing concentration and end in the triple point(C, 7 )[2.21] as follows from its definition (AS = 0). It is interesting to note that at this point the real Kauzmann temperature and the inverse Kauzmann temperature meet. But in real systems, the amorphous phase has an excess entropy (small fraction of the entropy of fusion) when compared to the corresponding crystal, the exact amount determined from the kinetics and timescale of the glass transformation. Therefore, another glass transition temperature line with finite excess entropy must be considered, which will be parallel to the Tg-line (above it) and cross the T0- and 77-lines not exactly in the triple point. 

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