Study On The Preparation Of Controlled Release Microcapsulation Of Rose Perfume

Microencapsulation is a technology of packing the objective (dye, paint, essence, pesticide, etc) into tiny particle with the filming material. It has the virtues of economizing stuff, reducing cost, decreasing pollution, the strong slow-release nature, etc, and can be applied to the field of chemical technology, pesticide, dress, foodstuff, chemical product of daily use.Two parts were included in this study, Microencapsulation of rose perfume with urea-formaldehyde resin wall were prepared by in-situ method in the first part. In preparation of urea-formaldehyde prepolymer of Rose perfume microcapsule with urea-formaldehyde wall, The addition reaction technology with alkali as the catalyzst was used. The effects of molar ratio of urea-formaldehyde, pH value of reaction medium, catalyst, reaction temperature on the structure of microcapsule and the microcapsulated ratio of the core material were studied. The optimized addition reaction conditions were as follows: the molar ratio of urea-formaldehyde n(urea):n(formaldehyde)=10:3, and the holding temperature is 50℃,and alkali catalyst used in the reaction was sodium hydroxide, and the pH value was 8.0, and the reaction temperature was 70℃ and the reaction time was 1h. The factors affecting microcapsulizing process were experimentally studied, the ratio of core material of MC, the size and distribution of microcapsules particles and structural characteristics were discussed. The optimal condition of condensation can be concluded as following: the weight of membrane material is 9%, NH4Cl can be as acid catalyst, acidizing time was 4h, end point pH value was 1.5, reaction temperature was between 60～70℃, reaction time was 2h. Under these conditions, the well microencapsulated fluidizable solid particles were prepared. The distribution of particle size was uniform and the average particle diameter was less than 3.5μm.Microencapsulation of rose perfume with cyclodextrin wall were prepared in the second part. To investigate overall influences of different factors on the ratio of core material of MC and controlled-release in preparation of microencapsulation, orthogonal experiment design method was used, and the suitable parameters for preparing microencapsulation of rose perfume were gained as following: the weight ratio of membrane material: core material was 10:3, and the holding temperature was 50℃, and the pH value was 7.0, and the consistency of cyclodextrin is 15%. Under these conditions, the well microencapsulated fluidizable solid particles were prepared.