Preparation and characteristics of sustained-release microcapsule-based inhibitory foam with high foaming ratio

To reduce the effect of conventional halogen salt inhibitors on the performance of foaming solutions and extend the fire prevention and suppression time of water-based foams, herein, microencapsulation technology has been used in the preparation of inhibitors. Calcium chloride sustained-release microcapsule with ethyl cellulose as wall material was successfully prepared by solvent evaporation method. The microcapsule complied with Higuchi release kinetics equation. The experiment showed that the foaming solution added with 20 g microcapsules had almost the same foaming capacity as the pure foaming solution, and the foaming multiple could reach 14 times, and the half-life of the foam could reach 123 min. The foaming multiple was much higher than the foaming multiple of calcium chloride foam (0 times). Compared with calcium chloride foam, the new type of foam prepared in this paper has better inhibition ability, and the inhibition rate is as high as 83.8%. Ethyl cellulose used as wall material in microcapsules can soften covered coal in the process of heating up, isolate coal and oxygen, and thus inhibit coal and oxygen binding. The experimental results show that the temperature of T1 (84.6 degrees C), T3 (338.2 degrees C) and the cross-point temperatures of the coal sample treated with the new type of foam are higher than that of the coal sample treated with the calcium chloride foam. At the same time, the new type of foam can significantly inhibit the oxidation rate of methyl and methylene. It can be seen that the microencapsulation technology can improve the ability of the inhibitor foam.