Striving for a less toxic production of metallized textiles - Environmental impact assessment

Abstract

Metallized textiles are novel materials that can be used in high value added functional goods, such as Assistive Technologies (AT) products. Potential issue with innovative metallization of textiles is the toxicity and environmental impact of the substances used in the process. To investigate this issue, this paper utilizes an original methodology of linking the analysis of toxicity of chemicals used in the textile metallization with Life Cycle Assessment (LCA) of the metallization process itself. This is done from the perspective of three relevant impact categories: global warming, toxicity and water use, for which, three methods were selected: IPCC et al., 2013 GWP 100a; USEtox 2 and Available WAter Remaining (AWARE). The LCA uses a mix of primary and secondary data and three cradle-to-gate scenarios were chosen for calculating results - first presenting just the metallization process itself, second taking into account alternative impregnation process and third including metallized surfaces - woven cotton and polyester. While the most toxic chemical identified was formaldehyde, the results of the LCA shows top processes contributing to global warming is the electricity consumption, the use of polyurethane with 0.996 kg CO2 eq. and EDTA with a result of 0.816 kg CO2 eq. The greatest impact on human toxicity and freshwater ecotoxicity comes from copper (II) chloride mostly used in the plating phase. Moreover polyurethane used in the impregnation phase leaves the largest water footprint of 0.984 m3. When taking into account the metallized surface scenario, the impact of cotton was high for global warming and water use and the impact of polyester was relatively low for all impact categories. The main conclusions of the research relate to the identification of cleaner production methods that could reduce the environmental footprint of the metallization of textiles. They include, among others: development of technology that can significantly increase resource productivity through selective metallization of conductive tracks; use of alternative formaldehyde-free and polyurethane-free chemicals; use of a closed loop system for water remaining in the technological process.