ISSN:
0098-1273
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The glass-transition temperatures of a series of copolymers of ethyl acrylate and acrylic acid neutralized with various cations were investigated. It was found that a plot of Tg as a function of ion content, for every type of ion investigated here, gives an unusual sigmoidal curve, which can be correlated with the onset of the failure of time-temperature superposition in viscoelastic studies, as will be shown in a future publication. Also, all of the Tg versus concentration curves for the various counterions can be superposed if the plots are made against cq/a, where c is the metal acrylate content, q the cation charge, and a the distance between centers of charge. Furthermore, in one region of water content, a linear relation is obtained between the glass transition and the water content (in weight-%) independent of the ion concentration over wide ranges of ion content. Finally, above an ion concentration of 12 mole-%, the rate of change in Tg per water molecule per ion pair at constant ion content, (∂Tg/∂n)c is linear but with different slopes above and below two water molecules per ion pair.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1976.180140705
