关键词: 剪切增稠液, 微胶囊, 单凝聚法, 单因素筛选, 防护性能

Abstract:

In this study， STF microcapsules （STF MCs） were prepared by using a monocoalescence method with chitosan material as a wall material and STF as a core material. The process parameters for the preparation of microcapsules were determined by a single⁃factor experimental study. Span 80 and Tween 80 were used as dispersants at a mass ratio of 3∶1， the addition amount of emulsifier was determined to be 11 wt%， the mass ratio of core to shell was determined to be 2∶1， the stirring speed was 600 r/min， the reaction temperature was 60 ℃， and the oil⁃to⁃water mass ratio of the system was 1∶2. The STF MCs produced under these conditions show a relatively regular spherical morphology with a relatively uniform distribution centered as a particle size of 3 μm. Rheological results indicated that the introduction of carbon nanotubes （CNTs） effectively improved the rheological properties of STFs. The CNTs⁃doped STF system exhibited a smaller critical shear rate， a faster viscosity transition， and an almost doubled peak viscosity. Infrared spectroscopic results indicated that the infrared spectrum of the microcapsule emulsion was almost consistent with that of the core. This indicated that chitosan was successfully adsorbed on the surface of the core droplets to realize the encapsulation of STFs. Thermogravimetric analysis results indicated the wall material could provide protection for the STF core， thus enhancing its thermal stability.

Key words: shear thickening liquid, microcapsule, complex coagulation method, single?factor filtering, protective performance