Solid amorphous polymers, molecular motion

PHOTOCHEMISTRY AND MOLECULAR MOTION IN SOLID AMORPHOUS POLYMERS... 

Photochemistry and Molecular Motion in Solid Amorphous Polymers 91... 

Recall that the diffusion coefficient in a glass of water equals 10 " - 10 cmVs, in melted polymer - 10 in a solid amorphous polymer - 10 , and in crystalline polymer - lO -lO" cmVs. Thus the molecule s motion and speed at transition from liquid low molecular compoimd to solid crystalline polymer may vary by 20 orders of magnitude or higher. Hence, a transition from kinetic area (when the reaction rate is defined by reactivities of the substances) to diffusion area (when the situation is completely defined by reagent delivery to the interaction site and the Frank-Rabinovich cage effect) may occur. 

GuiUet, J. E., Photochemistry and molecular motion in solid amorphous polymers, Adv. Photo-chem., 14, 91, 1988. 

In another paper in this issue [1], the molecular motions involved in secondary transitions of many amorphous polymers of quite different chemical structures have been analysed in detail by using a large set of experimental techniques (dynamic mechanical measurements, dielectric relaxation, H, 2H and 13C solid state NMR), as well as atomistic modelling. 

Investigation of the molecular motions involved in solid-state transitions of amorphous polymers (developed in [1]) has shown that it is interesting to... 

Polymers, Photochemistry and Molecular Motion in Solid Amorphous (Guillet). Primary Processes and Energy Transfer Consistent Terms and Deflnitions... 

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