Morphology of Burned Ultra-low Density Fiberboards

Abstract

The synergistic effect of two fire retardants, a Si-Al compound and chlorinated paraffin, was tested on ultra-low density fiberboards (ULDFs). To further understand the mechanism of fire retardancy, morphologies of unburned and burned ULDFs were studied using a scanning electron microscope with energy dispersive spectroscopy. It was found that as the volume of the burned ULDFs shrank, some crevices appeared. In addition, less fly ash formed on the top of specimens, and more bottom ashes remained in the original framework, with a clear network of structure built by the fibers. Carbon was almost absent in the fly ash; however, the weight ratio of C in the bottom ashes reached the maximum (> 43%) of the composition. Oxygen, Al, and Si appeared to have varying weight ratios for different ashes. Oxygen content increased with increasing Si and Al contents. Furthermore, Cl sharply decreased to less than 1% after combustion. Therefore, upon combustion, it was found that almost all of the substances in ULDFs, except for the Si-Al compound, were pyrolyzed to volatile carbon oxides and Cl compounds, especially the fly ash and lightweight C compounds.

Effect of Chlorinated Paraffin Nanoemulsion on the Microstructure and Water Repellency of Ultra-Low Density Fiberboard

“…It has an ultra-low density falling between 10 and 90 kg/m 3 . ULDF is favorable for noise reduction (noise reduction coefficient of 0.61 to 0.73), thermal insulation (0.02 to 0.038 W·m/K), and flame retardance (limiting oxygen index of 32) Niu et al 2014Niu et al , 2015a. It can also be used as cushioning in packaging and low-density wall and insulation materials.…”