Condis phase is more or less a known mesophase in polymers, and is referred to as a solid ordered (positional and orientational) phase, but conformationally disordered internally .
For me this glass state must exist, but I never have found any sample nor any experimetal result.
Dear Prof Kalogeras,
Thank you very much for your interesting answer. According to the Wunderlich book "Conformational Motion and Disorder in Low and High Molecular Mass Crystals" (number 87 of Advances in Polymer Science, Apringer-Verlag, 1988), condis phase should be considered a new (?) mesophase, that should appear between two first order transitions, one solid-condis-and another condis to liquid, or to any other mesophase as plastic crystal or liquid crystal. In this book, among several polymers, thallium alkanoates are cited as possible organic salts presenting not only one, but several condis mesophases (p. 82). We have studied thoroughly this series and we are agree in this point (we published a review of all of our works in this series in JCP (J. Chem. Phys.1999, 111, 3590). This behavior is typical of some polymers, but rather recently almost all of the organic salts are considered as MOFs. Now is accepted organic salts to be true coordination polymers (are known 1D, 2D and 3D coordination polymers of many organic salts).
We thought when we began of studding the lead(II) alkanoates series that should behave as a condis mesogens too, but we proved that the phase they present between an ordered crystal and a neat phase was not a condis, but a rotator phase. We published a paper on a nobel rotator glass of this phase (please find it in the list of our publications at Research Gate). Well, the question is that there shoul be at least 5 different glass states, amorphous (total disordered solid) condis glass (frozen defects of the internal conformational order of the chains), plastic crystal glass, liquid crystal glass, and rotator glass. We have seen in our studies glasses of all of them except plastic crystal glass and condis glass. There are many examples at the literature of plastic crystal glass (or ODIC, orientational disordered crystal), but none example of condis glass.
This glass is theoretical possible (frozen the conformational disordered chains).
The “delta Cp” of the rotator glass transition is very small, and is only seen if it is registered at very high heating rate. The same must be the condis glass transition.
Our interest is finding some example of a DSC measurement of a condis glass. We are studyng by modulated DSC a relaxation-cold crystallization process in an organic salt, effect very similar to that presents by PET and TEM. We are trying to find the condis glass transition with any success by now.
We will check your references on this mesophase. We appreciate very much you have sent to us this information.
Best regards
JAR Cheda
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