Eco-Friendly Coatings Containing Microcapsules with Fire-Resistant Properties

Abstract

The effect of microencapsulation of dihydrogen ammonium phosphate (MAP) in the generation of fire-resistant coatings was studied in the presence of tannins extracted from Pinus radiata. MAP was encapsulated to avoid interaction with sodium carbonate (Na 2 CO 3 ), which upon contact with fire, generates unwanted gases. Thus, a fireproof (or intumescent) protective film was produced in the presence of the tannins. Microcapsules were polymerized with melamine and characterized by FTIR, TGA, SEM-EDS. The microcapsules were spherical with a diameter between 0.7 and 1 µm. The as-produced microcapsules were mixed with tannin extract and the properties of their film were evaluated on wood and structural steel substrates; their fire resistance on medium density fiberboard was also evaluated. Flame resistance tests showed a carbonization index of 26.86% using microcapsules (3% w/w); this is better than commercial coatings. The film properties were similar to commercial coatings, but the adherence was slightly decreased, due to agglomeration and also films flexibility.Surfaces, Interfaces and Coatings Technology 4 www.videleaf.com