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Abstract This work utilizes frustrated Lewis pairs consisting of tethered bis‐organophosphorus superbases and a bulky organoaluminum to furnish the highly efficient synthesis of well‐defined triblock copolymers via one‐step block copolymerization of lignin‐based syringyl methacrylate andn‐butyl acrylate, through di‐initiation and compounded sequence control. The resulting thermoplastic elastomers (TPEs) exhibit microphase separation and much superior mechanical properties (elongation at break up to 2091 %, tensile strength up to 11.5 MPa, and elastic recovery up to 95 % after 10 cycles) to those of methyl methacrylate‐based TPEs. More impressively, lignin‐based tri‐BCPs can maintain TPEs properties up to 180 °C, exhibit high transparency and nearly 100 % UV shield, suggesting potential applications in temperature‐resistant and optical devices.
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This content will become publicly available on July 1, 2025
Supersoft Norbornene‐Based Thermoplastic Elastomers with High Strength and Upper Service Temperature
With over 6 million tons produced annually, thermoplastic elastomers (TPEs) have become ubiquitous in modern society, due to their unique combination of elasticity, toughness, and reprocessability. Nevertheless, industrial TPEs display a tradeoff between softness and strength, along with low upper service temperatures, typically ≤100 °C. This limits their utility, such as in bio‐interfacial applications where supersoft deformation is required in tandem with strength, in addition to applications that require thermal stability (e.g., encapsulation of electronics, seals/joints for aeronautics, protective clothing for firefighting, and biomedical devices that can be subjected to steam sterilization). Thus, combining softness, strength, and high thermal resistance into a single versatile TPE has remained an unmet opportunity. Through de novo design and synthesis of novel norbornene‐basedABAtriblock copolymers, this gap is filled. Ring‐opening metathesis polymerization is employed to prepare TPEs with an unprecedented combination of properties, including skin‐like moduli (<100 kPa), strength competitive with commercial TPEs (>5 MPa), and upper service temperatures akin to high‐performance plastics (≈260 °C). Furthermore, the materials are elastic, tough, reprocessable, and shelf stable (≥2 months) without incorporation of plasticizer. Structure–property relationships identified herein inform development of next‐generation TPEs that are both biologically soft yet thermomechanically durable.
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- Award ID(s):
- 2045336
- PAR ID:
- 10528484
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 36
- Issue:
- 30
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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