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Abstract Polyethylene (PE) is the most widely produced synthetic polymer. By installing chemically cleavable bonds into the backbone of PE, it is possible to produce chemically deconstructable PE derivatives; to date, however, such designs have primarily relied on carbonyl‐ and olefin‐related functional groups. Bifunctional silyl ethers (BSEs; SiR2(OR′2)) could expand the functional scope of PE mimics as they possess strong Si−O bonds and facile chemical tunability. Here, we report BSE‐containing high‐density polyethylene (HDPE)‐like materials synthesized through a one‐pot catalytic ring‐opening metathesis polymerization (ROMP) and hydrogenation sequence. The crystallinity of these materials can be adjusted by varying the BSE concentration or the steric bulk of the Si‐substituents, providing handles to control thermomechanical properties. Two methods for chemical recycling of HDPE mimics are introduced, including a circular approach that leverages acid‐catalyzed Si−O bond exchange with 1‐propanol. Additionally, despite the fact that the starting HDPE mimics were synthesized by chain‐growth polymerization (ROMP), we show that it is possible to recover the molar mass and dispersity of recycled HDPE products using step‐growth Si−O bond formation or exchange, generating high molecular weight recycled HDPE products with mechanical properties similar to commercial HDPE.
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Melt polycondensation of carboxytelechelic polyethylene for the design of degradable segmented copolyester polyolefins
Chain-transfer ring-opening metathesis polymerization (CT-ROMP) previously provided a route to carboxytelechelic polyethylene (PE) of controlled molecular weight; however, the incorporation of oligomeric PE into segmented copolymers remains unexplored. Herein, CT-ROMP afforded carboxytelechelic polycyclooctene segments, and subsequent reduction generated well-defined carboxytelechelic PE with M n = 3900 g mol −1 . Solvent-free melt polycondensation of neopentyl glycol and adipic acid with varying wt% telechelic PE oligomers yielded mechanically durable segmented copolyesters. The thermal and thermomechanical properties of the segmented copolyesters correlated with PE segment content, and high PE content copolymers exhibited remarkably similar morphologies and thermomechanical performance to conventional HDPE. The segmented copolyesters displayed advantageous physical properties while introducing susceptibility to chemo- and bio-catalytic depolymerization through periodic ester linkages, thus providing valuable fundamental understanding of an alternative route to HDPE.
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- PAR ID:
- 10342057
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 13
- Issue:
- 21
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 3116 to 3125
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/d2py00394e
