Preparation of surface-supported polypyrrole capsules using a solidified droplets template approach

Three-dimensional polypyrrole microcapsules were prepared via chemical deposition of the polymer onto tetradecanol particles supported on solid substrates. The growing polymer deposited onto the particle surface yielded hemispherical containers that encapsulated the tetradecanol contents. Mixing the tetradecanol with other chemical species, like fluorescent dyes, allowed the entrapment of these species within the containers. It was shown that by controlling the temperature, one could reversibly melt and solidify the tetradecanol content of the capsules. The tuning of the fluorescence intensity emitted from the capsules could thus be controlled. The polypyrrole structures were characterized using several complementary experimental methods. These included microscopic (scanning electron microscopy, atomic force microscopy, and optical microscopy) and spectroscopic techniques (steady-state fluorescence, ultraviolet-visual light absorption, and infrared spectroscopy) as well as conductivity and contact angle measurements.