Dissolution and regeneration of nylons utilizing superbase-acid conjugate ionic liquids
Eva Gazagnaire1, Yuliia Bardadym1, Sami Hietala1
1Materials Chemistry Division, Department of Chemistry, University of Helsinki 00560 Helsinki Finland aleksandar.todorov@helsinki.fi Ilkka.kilpelianen@helsinki.fi.
RSC Advances
|December 8, 2025
Summary
Recycling mixed nylon waste is difficult due to poor solubility. Certain superbase ionic liquids (SB-ILs) effectively dissolve and regenerate nylons without degradation, enabling sustainable nylon recycling.
Area of Science:
- Polymer Chemistry
- Materials Science
- Sustainable Chemistry
Background:
- Synthetic polyamides (nylons) possess valuable mechanical and chemical resistance properties.
- Recycling nylons, especially mixed waste streams, is challenging due to their poor solubility caused by interchain hydrogen bonding.
- Superbase ionic liquids (SB-ILs) are known for dissolving cellulose via hydrogen bond disruption.
Purpose of the Study:
- To investigate the potential of superbase ionic liquids (SB-ILs) for dissolving and regenerating nylon polymers.
- To explore the efficiency of SB-ILs in processing mixed nylon waste.
- To assess the stability and recyclability of SB-ILs in nylon dissolution-regeneration cycles.
Main Methods:
- Screening of various SB-ILs for nylon dissolution efficacy.
- Utilizing the most effective SB-IL, [dm3-mTBDH][OAc], for a nylon dissolution-regeneration process.
- Characterizing the regenerated nylon to assess polymer integrity and compare it with virgin materials.
Main Results:
- Many cellulose-dissolving SB-ILs can also dissolve nylons, with efficiency correlating to cation hydrophobicity.
- The SB-IL [dm3-mTBDH][OAc] demonstrated good performance in dissolving and regenerating nylons.
- Regenerated nylon showed no degradation compared to virgin samples, and the SB-IL remained stable over multiple cycles.
Conclusions:
- SB-ILs offer a viable pathway for dissolving and regenerating nylons, overcoming solubility limitations.
- This approach facilitates novel characterization techniques for nylon polymers.
- The findings open possibilities for efficient and sustainable recycling of nylon materials, including mixed waste streams.
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