Cold spots hypothesis

It was concluded33,34 these gelation phenomena are consistent with the segment-segment contact hypothesis of Frenkel et al. O We now extend this conclusion to include the earlier "cold spot" hypothesis of Ueberreiter. 30... 

Crystal growth by sublimation is extensively used for obtaining high purity crystals. The nucleation and growth of crystals from the vapor invariably occurs by grafting to some solid support, usually in practice some cold spot on the walls of a container. A likely hypothesis is then that the solid surface somehow acts as a nucleation catalyst. In principle, nothing forbids the simulation of the vapor-solid equilibrium along the same lines as for vapor-liquid equilibria. 

The basic hypothesis is that along any polymer chain there is a Maxwellian distribution of energies with several low energy "cold spots." Inter- and intra-association of cold spots gives rise to a structure which he assumed disappeared at a temperature which increased linearly with log molecular weight, much as Tyin Fig. 5. Ueberreiter s model for structure is inherently similar to that of Frenkel depicted by us in Fig. 9 of ref. 1, as segment-segment association which melts out at T//(see Fig. 11). 

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See also in sourсe #XX -- [ ]

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