| Fragrance is ubiquitous in our daily lives.Fragrance could be used in romantic perfumes for exaggerating atmosphere,the cosmetics for enhancing temperament,and even in the relaxing massages.Generally,people use a variety of spices,solvents and other additives to prepare essence.But traditional essence is sensitive to the environment,in order to delay the volatilization of it,prolong the retention time of essence,and prevent it from being oxidized when it is exposed to air,the essence is always sealed into the microcapsule to extend its usage time.In the study of fragrance microcapsules,researchers often focused on the selection of shell material of microcapsule and the simplest preparation method of this encapsulation process.In fact,the type of emulsifiers and its dosage can also greatly affect the encapsulation process,the particle size and encapsulation efficiency of fragrance microcapsules,and finally achieved fragrance microcapsules with high encapsulation efficiency and high stability.In this paper,fragrance microcapsules were prepared through interfacial polymerization method,monomers isocyanate,amine and their derivatives,which was widely used by researchers,were used as shell materials,marine essence was encapsulated as core material.The influence of emulsifiers’ type and the dosage on the encapsulation process were mainly investigated to obtain the optimized emulsifier that could encapsulate the fragrance,which at the same time possessed the high encapsulation efficiency,stable emulsion,small particle size and uniform particle size in this research.Moreover,the as prepared fragrance microcapsules were coated on cotton fabric and its characteristics and the application properties were also studied.The main contents of this paper included the following three aspects:(1)Impact of emulsifiers’ type on the encapsulation process and property of fragrance microcapsules: fragrance microcapsules were prepared by interfacial polymerization,isocyanate monomer and amine monomer were used as shell material,marine fragrance was used as core material,different kinds of emulsifiers,such as surfactant emulsifiers,polymer emulsifiers and compound emulsifiers which are mixtures of ionic emulsifier and nonionic emulsifier or mixed by two kinds of nonionic emulsifiers,were testified to obtain the optimized fragrance microcapsules.The morphology,particle size and size distribution,encapsulation efficiency of as prepared fragrance microcapsules were characterized by scanning electron microscope,laser particle size analyzer,ultraviolet spectrophotometer etc.The results showed that the fragrance microcapsule emulsified by no-ionic polymer emulsifier polyvinyl alcohol(88%)(PVA)possessed the most smooth morphology,narrowest size distribution,and the highest encapsulation efficiency,the fragrance microcapsule emulsified by compound emulsifier which was mixed by anionic emulsifier FES61 and no-ionic emulsifier A3065,achieved higher encapsulation efficiency than the fragrance microcapsule emulsified by FES61 or A3065 respectively,but its particle size distribution was broader,and the particle size of the fragrance microcapsule emulsified by compound emulsifier,mixtures of no-ionic polymer emulsifier PVA and anionic polymer emulsifier sodium polyacrylate(PAAS)was the smallest.(2)Impact of emulsifiers’ dosage on the property of fragrance microcapsules: different dosage of the two emulsifiers,PVA which can obtain the highest encapsulation efficiency of the fragrance microcapsules and F / A which can obtain the broadest particle size distribution of the fragrance microcapsules,was added to investigate its influence on the morphology,particle size and size distribution,encapsulation efficiency of fragrance microcapsules.Scanning electron microscope,laser particle size analyzer and ultraviolet spectrophotometer were applied to characterize its properties.The results showed that the optimized addition dosage of the two kinds of emulsifiers was 2.1 wt% and the as prepared fragrance microcapsules emulsified by them had the smallest particle size and the highest encapsulation efficiency in the same series,and the fragrance microcapsule emulsified by F / A had more concentrated particle size distribution with the increase of the amount of emulsifier.(3)Application of fragrance microcapsules in cotton fabric finishing: the emulsifier PVA and P / P,which can obtain the similar encapsulation efficiency of fragrance microcapsules,were applied on the cotton fabric.And the fragrance retention and slow-releasing property of fragrant fabric were characterized by the combination of subjective evaluation and objective analysis after soaping.The results showed that after five times of soaping,the content of fragrance on the fragrant cotton fabric finished with the fragrance microcapsule emulsified by PVA was almost zero while most of fragrance were retained on the cotton fabric finished with the fragrance microcapsule emulsified by P / P.That is,the small particle size fragrance microcapsule can be better applied to cotton fabric. |
