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Abstract Despite their industrial ubiquity, polyolefin‐polyacrylate block copolymers are challenging to synthesize due to the distinct polymerization pathways necessary for respective blocks. This study utilizes MILRad, metal–organic insertion light‐initiated radical polymerization, to synthesize polyolefin‐b‐poly(methyl acrylate) copolymer by combining palladium‐catalyzed insertion–coordination polymerization and atom transfer radical polymerization (ATRP). Brookhart‐type Pd complexes used for the living polymerization of olefins are homolytically cleaved by blue‐light irradiation, generating polyolefin‐based macroradicals, which are trapped with functional nitroxide derivatives forming ATRP macroinitiators. ATRP in the presence of Cu(0), that is, supplemental activators and reducing agents , is used to polymerize methyl acrylate. An increase in the functionalization efficiency of up to 71% is demonstrated in this study by modifying the light source and optimizing the radical trapping condition. Regardless of the radical trapping efficiency, essentially quantitative chain extension of polyolefin‐Br macroinitiator with acrylates is consistently demonstrated, indicating successful second block formation.
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Cu‐Catalyzed Atom Transfer Radical Polymerization: The Effect of Cocatalysts
Abstract Atom transfer radical polymerization (ATRP) is one of the most powerful methods to prepare well‐defined (co)polymers. Cu‐catalyzed ATRP methods are most commonly used because of the excellent control and tunable catalytic activities via ligand functionalization. This minireview summarizes the development of Cu‐catalyzed ATRP in the presence of cocatalysts, which are used to regenerate CuIcomplex activators during polymerizations. Fundamentals of Cu‐based ATRP catalysts are first introduced, followed by the discussion of different types of cocatalysts in different Cu‐catalyzed ATRP methods. Recent developments of photochemical cocatalysts for oxygen‐tolerant ATRP and ATRP using long‐wavelength irradiation are highlighted, which significantly expand the applications of Cu‐catalyzed ATRP. Methods to study the properties of cocatalysts and their roles in Cu‐catalyzed ATRP are discussed, with an outlook for the future development of cocatalysts.
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- Award ID(s):
- 2000391
- PAR ID:
- 10383244
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Macromolecular Chemistry and Physics
- Volume:
- 224
- Issue:
- 3
- ISSN:
- 1022-1352
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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