Life cycle assessment of thermal insulation materials produced from waste textiles

This study aims to produce sustainable thermal insulation materials from waste textiles and evaluate their environmental impact using life cycle assessment (LCA). In this study, three different insulation panels were produced using textile wastes at different percentages, temperatures, and pressure conditions. They are composed of 100% recycled cotton (N1), 90% recycled cotton/10% polylactic acid (PLA) (N2), and 42.5% recycled cotton/42.5% recycled nylon/15% PLA (N3). A cradle-to-gate LCA (starting from waste textile collection to the production of thermal insulation panels) was conducted to assess the key environmental impacts based on the ISO 14040/44 guidelines. Test results revealed that insulation materials produced from waste textiles have excellent thermal insulation properties. The obtained thermal conductive values of N1, N2, and N3 insulation materials are 0.027, 0.028, and 0.036 W/mK, respectively. In the case of environmental impacts, results showed that N1 and N2 insulation materials had lower environmental impacts than N3. Environmental impacts of produced insulation panels were also compared with some commercially available insulation materials (stone wool, recycled PET bottle, and flax). During comparison, the thickness of materials is adjusted to keep their thermal resistance value same (R = 1 m² K/W). The LCA results showed that the insulation panels N1 and N2 have eleven and three times (respectively) lower global warming (GW) potential than stone wool and sixteen and four times (respectively) lower GW potential than flax-based insulation panels and, therefore, could be considered as comparatively higher eco-friendly products. This LCA study also exposed a clear insight into the environmental impacts of several stages of the production process, which may be helpful to optimize or modify processes and produce more eco-friendlier thermal insulation material.