Thermal analysis, microstructure and acoustic characteristics of some hybrid natural insulating materials

Hybrid new insulating materials are proposed using different binders such as cornstarch, glue (wood adhesive) and white cement. Five hybrid samples were produced from date palm trees surface fibers (PTSF) and Apple of Sodom fibers (AOSF) for different ratio of mass and densities. One hybrid sample was produced from AOSF and agave fiber (AF) using glue (wood adhesive) as a binder. Thermal conductivity measurements were conducted for all samples at temperature ranging from 10 °C to 50 °C which resulted in average values of 0.04234–0.05291 W/m K. Microstructure analysis was conducted for AF using the scanning electron microscope (SEM) which resulted in an average diameter range of 170–259 μm. Infrared (FT- IR) Fourier transformation spectra of AF showed ranges of wavenumber functional groups. Thermogravimetric analysis (TGA and DTGA) was obtained for AF and showed that the fibers start to degrade and decompose at about 221 °C where the fiber loses 5% of its original mass. The Differential Scanning Calorimetry (DSC) analysis is also reported for AF and shows a broad endothermic transition range of 292–357 °C with a peak at 353 °C. Sound absorption coefficients were obtained for the hybrid samples and indicate the potential of using these samples for sound absorption. The current tests indicate the feasibility of using such hybrid samples as insulating materials for heat as well as sound absorption. The proposed tested hybrid samples are all natural, safe for human beings, utilize the wasted material and biodegradable therefore, it is good for saving our environment.