| Résumé : |
One thing is clear - a beautiful way that leather can compete against alternative materials is through its biodegradability. As mentioned before, not all leathers are biodegradable, especially as the plastic content of the surface coating increases. Carceone et al. (2023) has shown that leather has a high biogenic carbon content, white alternatives are essentially petroleum-based plastic.
Many of the petroleum-based plastics do not break down in aerobic or anaerobic conditions, persist in the environnent and could ultimately contribute to the increasing problem of micro and nano-plastics. Of the other materials showcased in the 2023 study, Carceone et al. showed that some new materials include biogenic carbon - with many of these based on cellulosic materials from waste plant sources. Industrial composting or anaerobic digestion can break these materials down, especially at high temperatures, e.g. polylactic acid coated cellulosic fibres. Contradictory reports exist for die breakdown of modified cellulosic fibres, such as Tencel, with some reports saying it can biodegrade and others that say it takes a timespan longer than 112 days to reach 60% in soil.
As reported previously, die speed of leather breakdown in composting always follows the following hierarchy : chromium-free > chromium-tanned > vegetable tanned. Adding vegetable tanning agents in die retannage slows down the breakdown of chromium-tanned leathers significantly. Chromium-free leathers, especially "half-tannages',' can result in complete breakdowns of leather (and their leather product articles) in less than 14 days - making them very exciting for supply chains with circularity in mind. |
Aller sur edunet
Accueil
Advances in biodegradability in INTERNATIONAL LEATHER MAKER (ILM), N° 60 (07-08/2023)
