| Interfacial polymerization method was employed to prepare polyuea microcapsules in this paper. Disperse dye microcapsules were applied in thermosol dyeing, transfer printing, multi-color and multi-dot printing and double sided printings. There is neither formaldehyde nor other pollutions when the microcapsules were being prepared and used. What more important is that, microcapsulated dyes can eliminate free dyes in waste water and lighten the environmental pollution. Microcapsulated dyes in the dyeing waste water can be separated by precipitation or filtration making the dyeing process environmental friendly and then obtain both economical and environmental benefits.The principle of polymerization is that isocyanate reacts with water and forms amine, and then the amine reacts quickly with unreacted isocyanate and forms polyurea.The core materials used in this experiment included disperse blue S-3BG, disperse blue 2BLN, disperse red 3B and disperse yellow E-3RL. Also, the liquid core materials were used in order to optimizing the microencapsulation conditions at the primary stage, e.g. the perfumes. The wall forming materials were TDI (2,4-toluene diisocyanate) or 80/20TDI, triphenyl methane triisocyanate and biphenyl methane-4, 4-diisocyanate (liquid MDI), Poly vinyl alcohol (PVA) was used as protective colloid and GPE2040 was used as the emulsifier. The Dibutyltin dilaurate was used as the catalyst.The effects of different elements on the morphology and particle size and the release property of disperse dye microcapsules were studied. Suitable microencapsulation techniques of disperse dyes for dyeing and printing were determined respectively.It is economic and convenient to prepare microcapsules to use this method and formulation. Fewer auxiliaries were used.The results indicated:1. During preparing microcapsules, n-butylamine and catalyst were added after the reaction was running 150min to complete the reaction. The residual isocyanate groups were not be detected(ASTM D2572-87)2. Smoother morphological structure and smaller particle size and narrower particle size distribution of microcapsules were obtained with the higher hydrophobicity of the core materials and catalyst in the aqueous phase. The morphological structures became coarser, particle sizes bigger and particle size distribution wider with increase in the amount of TDI. The morphological structures of microcapsules prepared at lower temperature were smoother. Three hours were enough to finish the shell forming polymerization. The particle sizes were bigger, particle sizedistributions were wider and the wall thicknesses were thicker with the increase in phase ratios (o/w) and decrease in core/wall ratios. And the particle sizes were smaller, particle size distributions were narrower and the wall thickness became thinner with increase in the amount of emulsifier, protective colloid, emulsifying speed and emulsifying time in the range of the experiments.3. Release rates and permeability constants decreased with increase in phase ratios and decrease in core/wall ratios. Release rates and permeability constants increased with the increase in the amount of emulsifier. Release rates increased and permeability constants hardly change with the increase in emulsifying speed and emulsifying time.4. The deeper color and better levelness were obtained when the disperse dye microcapsules were applied to thermosol dyeing with sodium alginate as anti-migrating agent. K/S value was the highest and color fastness was 3-4 and color staining was 4-5 with the disperse dyes microcapsules prepared as follow: emulsifier2040: 2.5%, phase ratio7:93, core/wall ratiol:3, protective colloid (PVA) 1%, emulsifying speed 9000rpm,emulsifying time lOmin and react time 3h. The effluent became clear after 150min stood, which made the waste water treatment very easy and more effective.5. Owing to its performance of releasing dyes with constant rate at elevated temperature with the microcapsules, prepared with the followin...
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