الفهرس 
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Abstract
It ie appeared from a:.literature eurvy on the only laboratory prepared reactive groupe that the epoxide group l!!Ihould have been amonget the commercially applied reactive dyeetuffe. Such reactive group and ite etable precursor, the chlorohydrin radical, have the property of reaction with different functional groupe of different textile fibres. It is thus capable of reaction with anione under acidic, neutral, and alkaline conditions
It was found that when epoxide dyeetuffs first claimed in 1950, a law colour yield was obtained when cellulosic fibres
• dye’ by the exhaustion method. By the padding technique a good
colour yield was obtained.
It was thought then that these results were due the low reactivi*F. of the epoxide group. Accordingly, the epoxide dyestuffs were only applied satisfactorily on silk and polyamide fibres. Some members of the ”Procionyf dyes (101)” based on epoxide group were claimed on 1958.
Few years later, the reactivity of the epoxide dyestuffs was investigated by Hopff in 1960. It was proved that the epoxide ring bad a moderate td,high reactivity •
Mean while, ·the development of techniques used for the
determination of physical properties of reactive dyes and their influence on the efficiency of the dyeing procedure, led to the expect ion that the reactivity of the epoxide ring was not the only factor affecting the exhaustion dyeing technique.
Throughout the present work; the physicochemical properties of reactive dyes containing epoxide group or its precursor, the chlorohydrin, as the reactive residue, were investigated.
Four dye-models were prepared; they covered varrying range ot reactivity, diffusivity,substantivity, and affinity, they
are : 1- acid dye-type contains no functional groups which may affect the reactivity of the epoxide ring.
·2- acid dye-type, the chromophoric system carrying nitro group which increase the reactivity.
).:. direct dye-type, the chromophoric system contains electron
- 2 -
4- direct dye-type, conta~ the sulphonamide group Wiich tends to increase the reactivity. Noting that dyes li2 have no substantivity for cellulose, on the contrary of dyes 3 and 4.
The diffusion coefficients of the prepared epoxide dyes were determined·by the time-lag method at different temperatures
and at different PH-values. From the results of these studies,
it was found that these dyes characterised with high diffusivity
even that of the direct dye-type.
On comparing the diffusivity of epoxide reactive orange (dye I) with ”procion yellow M-R (101)”, it was found that the diffusion coeffieient was seven times larger in the former ease. The,two dyes which have nearly the same molecular structure, were tested under the same conditions.
The affinities of the prepared dyestuffs were calculated from the data obtained through the diffusivity measurements. It was found that the prepared epoxide dyestuffs with very low aff~ inity incase of dyes one and two, and moderate affinity in ease of dyes three and :tour.
Substantivity of the prepared epoxide dyes was not determined directly. Alternatively the chromatographic scaning of dye solutions and the effect of electrolyte concentration on the RJ,i’-value, was taken as the change of dye substantivit1 With changing electroly~. concentration and temperature. It was found that the highly diffused dyes (dyes 1&2) did not affected mar~edly even when 60 g/l Nacl solution was used.
New simplified but accurate techniques were used for the determination of the reaction rate constant of the prepared epoxide dyes with cellulose and water. The reaction rate constant with cellUlose was determined as the overall rate constant. The absolute values were not tried in order to test the reactivity of the epoxide dyes under the paactical conditions of application.
The data obtained from the reactivity measurements at iifferent temperatures and under wide range of PH-values, prored that the reactivity of the prepared epoxide dyes with both ~ellulose and water coincided with the data obtained from Hopff’s studies.