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As rates of textile manufacturing and disposal escalate, the ramifications to health and the environment through water pollution, microplastic contaminant concentrations, and greenhouse gas emissions increases. Discarding over 15.4 million tons of textiles each year, the U.S. recycles less than 15%, sending the remainder to landfills and incinerators. Textile reuse is not sufficient to de-escalate the situation; recycling is necessary. Most textile recycling technologies from past decades are expensive, create low quality outputs, or are not industry scalable. For viability, textile recycling system designs must evolve with the rapid pace of a dynamic textile and fashion industry. For any design to be sustainable, it must also be flexible to adapt with technological, user, societal, and environmental condition advances. To this end flexible and sustainable design principles were compared: overlapping principles were combined and missing principles were added to create twelve overarching sustainable, flexible design principles (DfSFlex). The Fiber Shredder was designed and built with flexibility and sustainability as its goal and evaluated on how well it met DfSFlex principles. An evaluation of the Fiber Shredder's performance found that increased speed and processing time increases the generation of the desired output - fibers and yarns, manifesting the principles of Design for Separation in design and Facilitate Resource Recovery in processing. The development of this technology, with the application of sustainable and flexible design, fiber-to-fiber recycling using mechanical systems appears promising for maintaining value while repurposing textiles.
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Fluoride‐Catalyzed Siloxane Exchange as a Robust Dynamic Chemistry for High‐Performance Vitrimers
Abstract Sustainable development of new technologies requires materials having advanced physical and chemical properties while maintaining reprocessability and recyclability. Vitrimers are designed for this purpose; however, their dynamic covalent chemistries often have drawbacks or are limited to specialized polymers. Here, fluoride‐catalyzed siloxane exchange is reported as an exceptionally robust chemistry for scalable production of high‐performance vitrimers through industrial processing of commodity polymers such as poly(methyl methacrylate), polyethylene, and polypropylene. The vitrimers show improved resistance to creep, heat, oxidation, and hydrolysis, while maintaining excellent melt flow for processing and recycling. Furthermore, the siloxane exchange between different vitrimers during mechanical blending results in self‐compatibilized blends without any compatibilizers. This offers a general, scalable method for producing sustainable high‐performance vitrimers and a new strategy for recycling mixed plastic wastes.
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- Award ID(s):
- 1810217
- PAR ID:
- 10419230
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 35
- Issue:
- 28
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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