Study On Inclusion And Its Application Of Disperse Dye With β-Cyclodextrin

With characteristic molecular structures of β -cyclodextrin( β -CD), the solubility of disperse dyes can be improved and retarding and levelling performances can be obtained by including them into β -CD cavities,thus the novel use of β -CD will be achieved in textile industry. Due to non-toxic and biodegradable properties of β -CD, another important factor concerning possible applications in the field of textiles is that the use of β -CD does not cause any problems in waste water.So it can be foreseen that β -CD will have inestimable prospects for wide applications in dyeing processes.In this paper, two disperse dyes were chosen, The inclusion complex of disperse dyes and β -CD in 1:1 (V/V) ethanol/water solution were formed at 30℃,40℃,50℃,60℃,repectively. The absorbance of inclusion system was investigated via UV-Vis spectrophotometry. The experimental results indicated that they formed 1:1 (mole ratio) inclusion complexes according to Benesi-Hildebrand equation. The equilibrium constants were determined by the experimental results. The apparent thermodynamic parameters were also obtained and theysuggested that van der Waals force (AH<0,AS<0, governed by A H) was the major driving force for the inclusion system of disperse dyes with P-CD.Also, the solubility of disperse dye in co-solvent was determined by phase-solubility method. It was found that as the concentration of P-CD increased, the solubility also increased linearly, but when the value of concentration of P-CD was above 1.5xlO~3mol/L, it would be no increase further.Using C.I.Disperse Blue 72 and C.I.Disperse Red 60, p-CD in dyeing processes of PA6,6 at 80°C,90°C,98°Cand PET at 110°C,120 °C, 130"Cwere also applied,respectively.The conclusions were described as following:(1) For PA6,6, the use of P-CD caused the decrease of K/S values,while there was no big effect for PET.(2) P-CD was a good levelling agent in the dyeing process of PA6,6 .Especially for C.I.Disperse Blue 72 ,it was more markable, while on PET it was not as outstanding as on PA6,6.(3) P-CD was a good retarding agent in the dyeing process of PET, while it resulted in a decrease of adsorption amount of dyes on PA6,6.(4) The use of P-CD caused the decrease of dye strength on PA6,6, while there was no obvious effect on PET.( 5 ) For the two types of fabrics, the use of p-CD in dyeing processeshad no effect on the colorfastness to washing, rubbing and dry heating (or sublimation).