Abstract
It is empirically known that some organic compounds can be used in the case of dyeing polyethylene-terephathalate fiber as the accelerants (termed “carriers”). It may be thought that the glass-transition temperature of the fiber decreases with sorbing of the organic compounds, because the polymer chain may be loosened by sorbed compounds, and the dye molecule may diffuse more easily into the fiber.
In this study, the shrink-initiation temperature of the fiber was taken as the measure of the
glass-transition temperature and the effects of various kinds of organic compounds on decreasing the glass-transition temperature was examined for more than 50 compounds. The results obtained are that the shrink-initiation temperature decreases proportionaly to the amonut of sorbed compounds, within a limited width, having a little relation to the kind of compounds. And this relation appears most linearly when the amount of sorbed compound is represented by mol/kg fiber. This relationship may be interpreted in terms of the Fujita-Kishimoto's equation of free volume concept in polymer-diluent system.
It may be concluded that the organic compounds sorbed on polyethylene-terephthalate fiber make some bonds with polymer chain and increase the mobility of the polymer chain.
