Dispersion RAFT polymerization of 4-vinylpyridine in toluene mediated with the macro-RAFT agent of polystyrene dithiobenzoate: Effect of the macro-RAFT agent chain length and growth of the block copolymer nano-objects

2013 ◽  
Vol 51 (7) ◽  
pp. 1573-1584 ◽  
Author(s):  
Meihan Dan ◽  
Fei Huo ◽  
Xu Zhang ◽  
Xiaohui Wang ◽  
Wangqing Zhang
Keyword(s):  
Block Copolymer ◽  
Chain Length ◽  
Raft Polymerization ◽  
Raft Agent

Fluorinated amphiphilic block copolymers via RAFT polymerization and their application as surf-RAFT agent in miniemulsion polymerization

RSC Advances ◽  
2015 ◽  
Vol 5 (20) ◽  
pp. 15461-15468 ◽  
Author(s):  
Bishnu P. Koiry ◽  
Arindam Chakrabarty ◽  
Nikhil K. Singha
Keyword(s):  
Block Copolymer ◽  
Block Copolymers ◽  
Ethylene Glycol ◽  
Raft Polymerization ◽  
Miniemulsion Polymerization ◽  
Amphiphilic Block Copolymers ◽  
Poly Ethylene Glycol ◽  
Raft Agent ◽  
Poly Ethylene ◽  
Glycol Methyl Ether

Preparation of an amphiphilic block copolymer (Am-BCP) based on poly(ethylene glycol) methyl ether methacrylate (PEGMA) and heptafluorobutyl acrylate (HFBA) via RAFT polymerization and application of this Am-BCP as surf-RAFT agent for polymerization of styrene.

scholarly journals Fundamentals of reversible addition–fragmentation chain transfer (RAFT)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Catherine L. Moad ◽  
Graeme Moad
Keyword(s):  
Radical Polymerization ◽  
Chain Length ◽  
Molar Mass ◽  
Chain Transfer ◽  
Raft Polymerization ◽  
Length Distribution ◽  
Chain Length Distribution ◽  
Reversible Addition ◽  
Raft Agent ◽  
End Group

Abstract Radical polymerization is transformed into what is known as reversible addition–fragmentation chain transfer (RAFT) polymerization by the addition of a RAFT agent. RAFT polymerization enables the preparation of polymers with predictable molar mass, narrow chain length distribution, high end-group integrity and provides the ability to construct macromolecules with the intricate architectures and composition demanded by modern applications in medicine, electronics and nanotechnology. This paper provides a background to understanding the mechanism of RAFT polymerization and how this technique has evolved.

Macro-RAFT agent mediated dispersion polymerization: the monomer concentration effect on the morphology of the in situ synthesized block copolymer nano-objects

2015 ◽  
Vol 6 (46) ◽  
pp. 8003-8011 ◽  
Author(s):  
Zhonglin Ding ◽  
Chengqiang Gao ◽  
Shuang Wang ◽  
Hui Liu ◽  
Wangqing Zhang
Keyword(s):  
Block Copolymer ◽  
Dispersion Polymerization ◽  
Raft Polymerization ◽  
Monomer Concentration ◽  
Concentration Effect ◽  
Raft Agent

The great effect of the monomer concentration on the block copolymer morphology under dispersion RAFT polymerization is found and demonstrated.

An Ab Initio Investigation of the Chain-Length Dependence of the Addition–Fragmentation Equilibria in RAFT Polymerization

2011 ◽  
Vol 64 (6) ◽  
pp. 747 ◽  
Author(s):  
Ching Yeh Lin ◽  
Michelle L. Coote
Keyword(s):  
Hydrogen Bonding ◽  
Ab Initio ◽  
Chain Length ◽  
Raft Polymerization ◽  
Equilibrium Constants ◽  
Substituent Effects ◽  
Orbital Theory ◽  
Reversible Addition ◽  
Raft Agent ◽  
Length Effects

Ab initio molecular orbital theory has been used to study and explain the effects of chain length on the addition–fragmentation equilibrium constant in reversible addition–fragmentation chain transfer (RAFT) polymerization. New data is presented for azobisisobutyronitrile-initiated t-butyl dithiobenzoate-mediated polymerization of methyl methacrylate, and 2-(((ethylthio)carbonothioyl)thio)propanoic acid-mediated polymerization of acrylamide, and compared with published results for a dithiobenzoate-mediated polymerization of styrene and a trithiocarbonate-mediated polymerization of methyl acrylate. The effects of primary and penultimate substituents on the addition–fragmentation equilibrium constants in RAFT polymerization can be very large (up to eight orders and four orders of magnitude respectively) and should be taken into account in kinetic models. Antepenultimate unit effects are relatively small, implying that, for most systems, chain length effects have largely converged by the dimer stage. However, for sterically bulky monomers capable of undergoing anchimeric interactions such as hydrogen bonding, the onset and convergence of these substituent effects is delayed to slightly longer chain lengths. The magnitude and direction of chain-length effects in the addition–fragmentation equilibrium constants varies considerably with the nature of the RAFT agent, the initiating species, the propagating radical, and the solvent. The observed substituent effects arise primarily in the differing stabilities of the attacking radicals, but are further modified by homoanomeric effects and, where possible, hydrogen-bonding interactions.

Synthesis and characterization of a naphthalimide–dye end-labeled copolymer by reversible addition–fragmentation chain transfer (RAFT) polymerization

2011 ◽  
Vol 89 (3) ◽  
pp. 317-325 ◽  
Author(s):  
Binxin Li ◽  
Daniel Majonis ◽  
Peng Liu ◽  
Mitchell A. Winnik
Keyword(s):  
Chain Transfer ◽  
Raft Polymerization ◽  
Polymer Composition ◽  
Cooh Group ◽  
Agent Based ◽  
Molecular Weights ◽  
Reversible Addition ◽  
Raft Agent ◽  
End Use ◽  
Naphthalimide Dye

We describe the synthesis of an end-functionalized copolymer of N-(2-hydroxypropyl)methacrylamide (HPMA) and N-hydroxysuccinimide methacrylate (NMS) by reversible addition–fragmentation chain transfer (RAFT) polymerization. To control the polymer composition, the faster reacting monomer (NMS) was added slowly to the reaction mixture beginning 30 min after initating the polymerization (ca. 16% HPMA conversion). One RAFT agent, based on azocyanopentanoic acid, introduced a –COOH group to the chain at one end. Use of a different RAFT agent containing a 4-amino-1,8-naphthalimide dye introduced a UV–vis absorbing and fluorescent group at this chain end. The polymers obtained had molecular weights of 30 000 and 20 000, respectively, and contained about 30 mol% NMS active ester groups.

One-pot synthesis of PLA-b-PHEA via sequential ROP and RAFT polymerizations

2017 ◽  
Vol 8 (39) ◽  
pp. 6086-6098 ◽  
Author(s):  
Ilknur Yildirim ◽  
Pelin Sungur ◽  
Anna C. Crecelius-Vitz ◽  
Turgay Yildirim ◽  
Diana Kalden ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Ring Opening ◽  
Raft Polymerization ◽  
Ring Opening Polymerization ◽  
One Pot ◽  
One Pot Synthesis

A block copolymer library of polylactide and poly(2-hydroxyethyl acrylate) was prepared via sequential ring opening polymerization and RAFT polymerization in a one-pot approach.

Dependence of cross-termination rate on RAFT agent concentration in RAFT polymerization

2017 ◽  
Vol 25 (9) ◽  
pp. 931-935 ◽  
Author(s):  
Yanggang Gao ◽  
Ling Lv ◽  
Gang Zou ◽  
Qijin Zhang
Keyword(s):  
Raft Polymerization ◽  
Termination Rate ◽  
Raft Agent
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