Preparation and characterization of microcapsules for cleaning products and cosmetics

Microcapsules including multilayer are expected to be more effective in protection and controlled release than single layered microcapsules. A previous study of mononuclear polyurea and urea-formaldehyde (PU/UF) double wall microcapsules, which was performed to observe the release of the color of Oil Red that was used as a core material, revealed that more amount of core material can be protected for a long time and at high temperatures by the double wall microcapsules. Although the results of the previous study were optimistic for microencapsulation, formation of broken microcapsules were observed. For the improvement of the microensapsulation for fragrances to be used in cleaning products, firstly the single wall mono-core urea-formaldehyde (UF) microcapsules including fragrance as core material were formed and studied. The most successful trial was performed by using Polyvinylpyrrolidone as polymeric material while the in-situ reaction was carried out at 600 rpm in two hours. In the formation process of PU/UF microcapsules, microcapsules were observed to be broken down due to drying process under vacuum oven. After solving varying problems with alternative methods, well-formed (size of 2.1 m), powder-like and homogenously dispersed microcapsules having high thermal stability without agglomeration were obtained in high amount. Apart from these studies, a matrix type of bio-microcapsules including tea extracted caffeine, plant extracts and fragrance to be used as an anti-cellulite peeling in the cosmetics applications was obtained and studied by using complex coacervation method. The capsules were observed in gel-like form in that the polymeric matrix includes carboxymethyl cellulose (anionic polymer) and aqueous chitosan (cationic polymer). According to the data obtained from microbiological analyses and human volunteers, the final product of the peeling was determined to be effective on cellulite treatment and to be microbiologically available for continuous industrial production. Thus, the study will be a useful guide for applying different microencapsulation techniques for various purposes.