Calorimetric test of the photonic crystal globules growth process

Authors: Galkin N.K.
Published in issue: #7(24)/2018
DOI: 10.18698/2541-8009-2018-7-342
Category: Chemistry | Chapter: Organic Chemistry
Keywords: calorimetry, photonic crystals, synthesis, monodispersity, spectroscopic measurements, stop zone
Published: 24.07.2018

The article analyzes the process of photonic crystals synthesis with the help of calorimetric measurements. We have obtained the heat generation graphs in the process of future photonic crystal’s sol synthesis. Characteristic parts of the graphs conform with endo- and exo-effects: in case of the endoeffect the organic and nonorganic phases mix and the monomer hydrolysis process occurs, while in case of the great exo-effect the polyfunctional condensation reaction takes place and the solid phase nuclei growth is activated. According to the estimate of the reaction completion degree its value is about 6% of the total number of the silanol bonds, which is indicative of the loose structure of the sol obtained. After removing the solvent the monodisperse iridescent specimens were derived. By applying the spectroscopic measurements we have determined the particle sizes.

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