Abstract: The aerogel particle is a kind of ultra-light material with a three-dimensional porous network structure and a high porosity within. The porous structure and excellent mechanical stability of aerogel make it an ideal carrier for essence, phase change materials and even drugs, and an ideal material for preparing slow-release microcapsules. To explore the application of aerogel particles in the preparation of aromatic fibers, the SiO2 aerogel microcapsules loaded with essence were mixed into polyvinyl alcohol (PVA) spinning solution, and PVA aromatic fibers were prepared by wet spinning process. The effect of  the addition amount of aromatic microcapsule on the viscosity and dispersion of the spinning solution, morphology, basic properties, and slow-release performance of the aromatic fibers were studied. 
It was found that with the increase of the amount of SiO2 aerogel aromatic microcapsules, the viscosity of PVA spinning solution gradually increased, and the microcapsules gradually clustered in the spinning solution. When the addition amount was higher than 7%, the aromatic microcapsules exhibited obvious agglomeration phenomenon in the spinning solution, making the spinning process more difficult. Aromatic fibers were prepared from PVA spinning solution containing 4% of SiO2 aerogel aromatic microcapsules, and the longitudinal morphology of the obtained fibers was basically the same as that of pure PVA fibers. The aerogel aromatic microcapsules were embedded in the fibers and well dispersed. SiO2 aerogel aromatic microcapsules and the prepared aromatic fibers have excellent slow-release properties. After being placed at room temperature for 60 days, their essence release rates were only 22.2% and 13.4%, and their fragrance retention performance was significantly better than that of aromatic microcapsules and aromatic fabrics prepared by conventional polymer embedding method, such as polymethyl methacrylate, melamine/formaldehyde resin and polyurethane. The thermal properties and tensile mechanical properties of PVA fibers decreased significantly after the addition of SiO2 aerogel aromatic microcapsules. This probably resulted from the increase of void space in the fibers caused by aromatic microcapsules; aromatic microcapsules also interfered with orientation arrangement and crystallization formation of PVA fibers, causing a disordered aggregation structure of in the blend fibers.
This study is of great significance for the application of aerogel particles in the preparation of slow-release functional microcapsules and their functional fibers.

Key words: SiO2 aerogel, aromatic microcapsules, aromatic fiber, slow-release property, wet spinning, PVA

摘要： 为探索气凝胶颗粒在芳香纤维制备中的应用，将负载有香精的SiO2气凝胶颗粒掺入聚乙烯醇（PVA）纺丝液中，利用湿法纺丝工艺制备了芳香纤维，并研究了芳香微胶囊添加量对纺丝液粘度及分散性的影响，同时探究了芳香纤维的形貌、热学性能、力学性能及芳香缓释性能。研究表明：共混纺丝液的粘度随SiO2气凝胶芳香微胶囊添加量的增加而增大，添加质量分数超过4%后，芳香微胶囊在纺丝液中开始团聚，添加量超过7%后，纺丝较困难；随着SiO2气凝胶芳香微胶囊含量的增加，芳香纤维的应力、应变及热学性能均相应降低；该芳香微胶囊和芳香纤维具有较好的留香性能，室温下放置60 d后，芳香微胶囊和芳香纤维中的精油残留率仍有77.8%和86.6%。研究结果对气凝胶颗粒在制备缓释功能微胶囊及其功能纤维中的应用具有重要意义。

关键词: SiO2气凝胶, 芳香微胶囊, 芳香纤维, 缓释性能, 湿法纺丝, PVA