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Abstract Good control of tacticity, molecular weight, and architecture is attained via atom transfer radical polymerization (ATRP) ofN‐hydroxyethyl acrylamide (HEAA), in a one‐pot process in the presence of Y(OTf)3. The effect of temperature, ratio of [Y(OTf)3]/[HEAA], and ATRP procedure on the tacticity and degree of control over the polymerization is investigated in detail. Under optimal conditions, using photo ATRP and 15% Y(OTf)3,the content of meso dyads (m) can be increased from 42% to 80% in a homopolymer with a dispersityD = 1.22. Well‐defined stereoblock copolymers, atactic‐b‐isotactic poly(HEAA), withD = 1.27, are obtained by adding Y(OTf)3at a specific conversion, initially started without Y(OTf)3.
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Biocatalytic “Oxygen‐Fueled” Atom Transfer Radical Polymerization
Abstract Atom transfer radical polymerization (ATRP) can be carried out in a flask completely open to air using a biocatalytic system composed of glucose oxidase (GOx) and horseradish peroxidase (HRP) with an active copper catalyst complex. Nanomolar concentrations of the enzymes and ppm amounts of Cu provided excellent control over the polymerization of oligo(ethylene oxide) methyl ether methacrylate (OEOMA500), generating polymers with high molecular weight (Mn>70 000) and low dispersities (1.13≤Đ≤1.27) in less than an hour. The continuous oxygen supply was necessary for the generation of radicals and polymer chain growth as demonstrated by temporal control and by inducing hypoxic conditions. In addition, the enzymatic cascade polymerization triggered by oxygen was used for a protein and DNA functionalized with initiators to form protein‐b‐POEOMA and DNA‐b‐POEOMA bioconjugates, respectively.
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- Award ID(s):
- 1707490
- PAR ID:
- 10079160
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 57
- Issue:
- 49
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 16157-16161
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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