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Abstract The development of chemically recyclable polymers promises a closed‐loop approach towards a circular plastic economy but still faces challenges in structure/property diversity and depolymerization selectivity. Here we report the first successful coordination ring‐opening polymerization of 4,5‐trans‐cyclohexyl‐fused γ‐butyrolactone (M1) with lanthanide catalysts at room temperature, producing P(M1) withMnup to 89 kg mol−1, high thermal stability, and a linear or cyclic topology. The same catalyst also catalyses selective depolymerization of P(M1) back toM1exclusively at 120 °C. This coordination polymerization is also living, enabling the synthesis of well‐defined block copolymer.
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Effects of Chain Ends on Thermal and Mechanical Properties and Recyclability of Poly( γ ‐butyrolactone)
ABSTRACT This work investigates effects of poly(γ‐butyrolactone) (PγBL) with different initiation and termination chain ends on five types of materials properties, including thermal stability, thermal transitions, thermal recyclability, hydrolytic degradation, and dynamic mechanical behavior. Four different chain‐end‐capped polymers with similar molecular weights, BnO‐[C(=O)(CH2)3O]n‐R, R = C(=O)Me, C(=O)CH=CH2, C(=O)Ph, and SiMe2CMe3, along with a series of uncapped polymers R′O‐[C(=O)(CH2)3O]n‐H (R′ = Bn, Ph2CHCH2) withMnranging from low (4.95 kg mol−1) to high (83.2 kg mol−1), have been synthesized. The termination chain end R showed a large effect on polymer decomposition temperature and hydrolytic degradation, relative to H. Overall, for those properties sensitive to the chain ends, chain‐end capping renders R‐protected linear PγBL behaving much like cyclic PγBL. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2018,56, 2271–2279
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- Award ID(s):
- 1664915
- PAR ID:
- 10075070
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Polymer Science Part A: Polymer Chemistry
- Volume:
- 56
- Issue:
- 20
- ISSN:
- 0887-624X
- Page Range / eLocation ID:
- p. 2271-2279
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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