Application of raw sheep wool waste for the production of sustainable and energy-efficient insulation materials

This article presents the development of nonwoven thermal insulation materials made from natural sheep wool, aimed at enhancing energy efficiency in construction. The study applies a mathematical experiment planning method (KONO-2) to assess the influence of technological parameters, such as fiber type, basis weight, and binder content, on the material properties. As a binder, bicomponent fibers composed of a polyester core and a polyethylene sheath were used, providing effective bonding between fibers and improving the structural integrity of the nonwoven fabric. Key performance indicators, including thermal conductivity, mechanical strength, elongation, and air permeability, were evaluated across a range of basis weights (200–300 g/m²) and bicomponent fiber contents (10–30%). The results demonstrate that materials made from fine wool exhibit lower thermal conductivity (0.0216 W/m·K) compared with those made from coarse wool (0.0312 W/m·K). The best insulation performance was achieved in samples containing 70% wool and 30% bicomponent fiber with a basis weight of 250 g/m². This study introduces an innovative approach to utilizing sheep wool waste for producing sustainable, energy-efficient insulation materials, offering a promising alternative to conventional synthetic insulations in the building industry.