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Updated: Aug 13, 2026
05:48
Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Low-temperature depolymerization of nylon-6 and other polyamides mediated by boron-based Lewis acids
Tanveer Mahmadalli Shaikh1, Arumugam Sudalai1, Changbum Jo1
1Department of Chemistry and Chemical Engineering, Inha University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea. jochangbum@inha.ac.kr.
Chemical Communications (Cambridge, England)
|August 12, 2026
Summary
This study presents an efficient nylon-6 depolymerization method yielding high-purity 6-aminocaproic acid hydrochloride (6ACA·HCl). This sustainable process simplifies purification and enables conversion to valuable ε-caprolactam.
Area of Science:
- Polymer Chemistry
- Sustainable Chemistry
- Organic Synthesis
Background:
- Nylon-6 is a widely used synthetic polymer with environmental persistence.
- Efficient recycling methods for nylon-6 are crucial for sustainable material management.
- Depolymerization to monomers or valuable intermediates is a key recycling strategy.
Purpose of the Study:
- To develop an efficient and clean method for nylon-6 depolymerization.
- To obtain high yields of 6-aminocaproic acid hydrochloride (6ACA·HCl).
- To assess the potential of the product for further chemical conversion.
Main Methods:
- Nylon-6 depolymerization under mild reaction conditions.
- Characterization of the reaction product, 6ACA·HCl.
- Evaluation of the conversion of 6ACA·HCl to ε-caprolactam.
Main Results:
- Achieved >99% yield of 6-aminocaproic acid hydrochloride (6ACA·HCl).
- The reaction proceeded under mild conditions with no detectable organic by-products.
- Obtained a 78% yield of ε-caprolactam from the synthesized 6ACA·HCl.
Conclusions:
- Developed a highly efficient and environmentally friendly method for nylon-6 depolymerization.
- The process yields a pure, commercially valuable intermediate (6ACA·HCl) suitable for ε-caprolactam production.
- This method offers a sustainable route for nylon-6 recycling and valorization.
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