Thermal characterisation of insulation panels based on vegetable typha domengensis and starch

Abstract

The thermal characteristics of a typha-starch composite have been determined in this study in order to improve thermal comfort of the buildings in tropical environments. From six samples of this mixture of granulometry (0.425 mm; 1.25 mm and 1.70 mm), the kinetics of the water desorption have been characterized and the thermal properties of these materials were also studied. The results obtained indicate that the samples have a high rate of water desorption recorded in the first ten and fifteen days with proportions in loss of water which vary from 7% to 18.75%. The thermal conductivity obtained for samples without a binder (starch) varies from 0.1046 W.m−1K−1 to 0.1242 W.m−1K−1 and from 0.094 W.m−1K−1 to 0.5345 W.m−1K−1 for the composites. The thermal diffusivity evolves between 9.010−8 m².s−1 and 3.77.10−7m².s−1. In view of these results and according to the American National Standards Institute (ANSI 208, 1999), all the samples prepared except the formulation (0.425 mm + 20% starch) have good thermal properties for improving thermal comfort of buildings and the composite fraction (typha 1.70 mm + 20% starch) seems to be the optimal composition. The latter could be recommended as a local available insulation material to be integrated into the buildings in tropical environments in the form of sub-ceiling, instead of the widely used Isorel insulation panels (k = 0.82 W.m−1K−1) and plywood panels (k = 1.08 W.m−1K−1) of higher thermal conductivities and cost. For the first time in Africa, such a combination of local materials (Typha-amidon) used to improve energy efficiency has been demonstrated on the roof of the building envelope. The resulting scientific advances are linked to the originality of the formulation and the proportions of each material used to obtain the best composite. The development impacts of its implementation are directly linked to Sustainable Development Goals 1, 2, 7, 8, 14 and 15 (SDGs), as well as the African Union's Agenda 2063.