| Autor: |
Gurion, Z., Ingamells, W., Peters, R. H. |
| Předmět: |
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| Zdroj: |
Book of Papers, National Technical Conference of AATCC; 1981, p89-108, 20p |
| Abstrakt: |
The dyeing of Acrilan with disperse dyes in the presence of benzyl alcohol is controlled by the segmental mobility of the polymer chains. Benzyl alcohol acts as a plasticizer and reduce the glass transition temperature (Tg) of the fiber in proportion to its concentration in the fiber and this plasticizing action is responsible for the enhanced rate of dyeing observed in the presence of benzyl alcohol in the dyebath solution. The diffusion coefficient (DT) of C. I. Disperse Orange 3 into Acrilan is controlled by the difference between the dyeing temperature (T) and the glass transition temperature of the fiber (Tg) and can be increased either by increasing T, decreasing Tg, or both. Arrhenius curves describing the variation of log DT against 1/T in the presence of various concentrations of benzyl alcohol are non-linear and the activation energy for diffusion increases dramatically as the dyeing temperature falls toward the Tg. The variation of the diffusion coefficient of C. I. Disperse Orange 3 with dyeing temperature and benzyl alcohol concentration can be described by the WLF equation. The glass transition temperature of Acrilan in pure benzyl alcohol is very close to that in water and increasing the amount of water dissolved in the alcohol reduces the Tg further in direct proportion to the concentration of water Consequently, it does not matter whether the dyeing media is water dissolved in benzyl alcohol or benzyl alcohol dissolved in water, since in both cases benzyl alcohol plasticizes the fiber. The plasticization of Acrilan by benzyl alcohol is accompanied by only minimal swelling of the fiber which is not in proportion to the large reduction in Tg. Furthermore, the plasticization in benzyl alcohol solutions containing small amounts of water is accompanied by radial contraction rather than swelling of the riber. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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