Transition Motions in Pure Aryl-aliphatic Epoxy Resins

Conclusions on p Transition Motions in Pure Aryl-aliphatic Epoxy Resins 

The dynamic mechanical results and the solid-state 13C NMR measurements lead to a deeper insight of the motions occurring below the glass transition temperature in the considered pure aryl-aliphatic epoxy networks, in particular those involved in the p transition of these systems, and the nature of their cooperativity. 

The ft transition clearly originates from motions of the hydroxypropyl ether sequence, but the crosslink points are also involved. Whereas the motions involved in the low-temperature part of the ft transition are quite isolated motions of HPE units, when temperature increases a cooperativity appears directly with the mobility of the crosslinks and, indirectly, with the jr-flip motions of the DGEBA phenyl rings. 

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