关键词: 微胶囊, 核壳型, 破胶剂, 原位聚合法

Abstract:

Microcapsules with ammonium persulfate as the core materials and polypyrrole as the shell materials were prepared by in-situ polymerization. The morphologies and structures of the microcapsules were analyzed by the scanning electron microscopy, laser particle size analyzer, infrared spectrum and Raman spectrum. The results show that the particle size distribution of the microcapsules was concentrated at 100-300 nm, and polypyrrole was successfully coated with ammonium persulfate. The change in the conductivity of the microcapsules when dispersed in water indicates that the release process of the microcapsules was osmotic release. As the amount of glycerol increased, the water absorbed rate of the microcapsules was accelerated, the dissolution rate of the internal solid ammonium persulfate increased, and the release rate of the corresponding ammonium persulfate increased. Ammonium persulfate and microcapsules of equal mass were separately added to the polymer fracturing fluid, and by the high temperature viscosity reduction experiments, it was found that the microcapsules could delay gel breaking for more than 7 h.

Key words: microsphere, core-shell;breaker, in-situ polymerization