Commonly used insulation, such as fiberglass and expanded polystyrene foam, are made from petroleum resins, which are not very environmentally friendly. As a result, various groups began to look into more environmentally friendly alternatives. It would be even better if the materials used in these substitutes would otherwise be discarded haphazardly. Although various uses for post-harvest rice husk waste are being explored, these are often either incinerated, thrown into landfills, or at most composted. However, rice husks can soon be combined with discarded newspapers to form environmentally friendly insulation.
A team of scientists at the Universidad Tecnológica de Panamá, led by Dr. Nacarí Marín Calvo, recently turned their attention to rice husks, which are produced in large quantities in rural areas of Panama. Panama, like most other countries, has a large collection of old newspapers to take advantage of.
To make the insulation, the researchers first shredded rice husks and newspapers, and then extracted cellulose from the latter. Subsequently, chaff and cellulose are mixed with glue (as a binder) and borax (for fire and fungal resistance) in three different proportions.
It was found that the k-values (thermal conductivity), tensile strength (the ability to stretch without breaking), and compressive strength (the ability to withstand extrusion) for all three ratios were consistent with other natural and ** insulation.
The four components of the insulation are mixed in three different proportions Figure of the Technical University of Panama, research group: Iniciativa de Integración de Tecnologías para el Desarrollo de Soluciones Ingenieriles (I2TEDsi).
Further research will focus on evaluating the rate at which insulation degrades under various conditions, as well as how effective it is at preventing heat from escaping from the room. Scientists will also explore its applications in other areas, such as architectural panels and sustainable packaging.
The study was recently published in the journal Frontiers in Built Environment.