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Title: Redesigned Nylon 6 Variants with Enhanced Recyclability, Ductility, and Transparency
Abstract Geminal (gem−) disubstitution in heterocyclic monomers is an effective strategy to enhance polymer chemical recyclability by lowering their ceiling temperatures. However, the effects of specific substitution patterns on the monomer's reactivity and the resulting polymer's properties are largely unexplored. Here we show that, by systematically installinggem‐dimethyl groups onto ϵ‐caprolactam (monomer of nylon 6) from the α to ϵ positions, both the redesigned lactam monomer's reactivity and the resultinggem‐nylon 6’s properties are highly sensitive to the substitution position, with the monomers ranging from non‐polymerizable to polymerizable and thegem‐nylon properties ranging from inferior to far superior to the parent nylon 6. Remarkably, the nylon 6 with thegem‐dimethyls substituted at the γ position is amorphous and optically transparent, with a higherTg(by 30 °C), yield stress (by 1.5 MPa), ductility (by 3×), and lower depolymerization temperature (by 60 °C) than conventional nylon 6.  more » « less
Award ID(s):
2247666
PAR ID:
10522743
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Angewandte Chemie International Edition
Volume:
63
Issue:
17
ISSN:
1433-7851
Subject(s) / Keyword(s):
Nylon-6 substituted Nylon-6 improved properties mechanical properties optical properties
Format(s):
Medium: X Size: 3MB
Size(s):
3MB
Sponsoring Org:
National Science Foundation
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