scholarly journals Imidazole-containing triblock copolymers with a synergy of ether and imidazolium sites

2015 ◽  
Vol 3 (16) ◽  
pp. 3891-3901 ◽  
Author(s):  
Chainika Jangu ◽  
Jing-Han Helen Wang ◽  
Dong Wang ◽  
Gregory Fahs ◽  
James R. Heflin ◽  
...  
Keyword(s):  
Chain Transfer ◽  
Triblock Copolymers ◽  
Raft Polymerization ◽  
Reversible Addition

Reversible addition–fragmentation chain transfer (RAFT) polymerization enabled the synthesis of well-defined A–BC–A triblock copolymers containing a synergy of pendant ether and imidazolium sites.

Synthesis, self-assembly and self-healing properties of organic–inorganic ABA triblock copolymers with poly(POSS acrylate) endblocks

2019 ◽  
Vol 10 (19) ◽  
pp. 2424-2435 ◽  
Author(s):  
Bingjie Zhao ◽  
Sen Xu ◽  
Sixun Zheng
Keyword(s):  
Self Assembly ◽  
Triblock Copolymer ◽  
Chain Transfer ◽  
Triblock Copolymers ◽  
Raft Polymerization ◽  
Self Healing ◽  
Reversible Addition ◽  
Aba Triblock Copolymer

A novel organic–inorganic ABA triblock copolymer with a poly(acrylate amide) (PAA) midblock and poly(POSS acrylate) [P(POSS)] endblocks was synthesized via sequential reversible addition–fragmentation chain transfer (RAFT) polymerization.

Preparation of Thermo-Sensitive Supramolecular Hydrogels Formed from MPEG-b-PNIPAM-b-MPEG Triblock Copolymer with α-Cyclodextrin

2014 ◽  
Vol 934 ◽  
pp. 75-79 ◽  
Author(s):  
Xiao Feng Ye ◽  
Mi Zhou ◽  
Jing Ying Hu ◽  
Xin Qian
Keyword(s):  
Triblock Copolymer ◽  
Chain Transfer ◽  
Triblock Copolymers ◽  
Raft Polymerization ◽  
Inclusion Complexation ◽  
Gel Permeation Chromatography ◽  
H Nmr ◽  
Reversible Addition ◽  
Response Interval ◽  
Gel Permeation

To develop a new drug delivery matrix with the suitable responsive interval, a well-defined triblock copolymer MPEG-b-PNIPAM-b-MPEG was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. Then, the supramolecular hydrogels were fabricated via inclusion complexation with α-cyclodextrin (α-CD) and the triblock copolymers in aqueous solutions. The triblock copolymers were characterized by 1H NMR and gel permeation chromatography (GPC), and the supramolecular structures of hydrogels was confirmed by DSC. The resultant hydrogels was found to be thermo-sensitive, and the response interval could be modulated by controlling the content of PNIPAM.

scholarly journals One-pot synthesis of block-copolyrotaxanes through controlled rotaxa-polymerization

2017 ◽  
Vol 13 ◽  
pp. 1310-1315 ◽  
Author(s):  
Jessica Hilschmann ◽  
Gerhard Wenz ◽  
Gergely Kali
Keyword(s):  
Chain Transfer ◽  
Triblock Copolymers ◽  
Raft Polymerization ◽  
Aqueous Solubility ◽  
One Pot ◽  
Polymer Backbone ◽  
One Pot Synthesis ◽  
Reversible Addition ◽  
First Time ◽  
Polymerization Conditions

The aqueous reversible addition fragmentation chain-transfer (RAFT) copolymerization of isoprene and bulky comonomers, an acrylate and an acrylamide in the presence of methylated β-cyclodextrin was employed for the first time to synthesize block-copolyrotaxanes. RAFT polymerizations started from a symmetrical bifunctional trithiocarbonate and gave rise to triblock-copolymers where the outer polyacrylate/polyacrylamide blocks act as stoppers for the cyclodextrin rings threaded onto the inner polyisoprene block. Statistical copolyrotaxanes were synthesized by RAFT polymerization as well. RAFT polymerization conditions allow control of the composition as well as the sequence of the constituents of the polymer backbone which further effects the CD content and the aqueous solubility of the polyrotaxane.

Morphology Transitions in RAFT Polymerization

2012 ◽  
Vol 531-532 ◽  
pp. 284-289
Author(s):  
Chuan Qun Huang ◽  
Cai Yuan Pan
Keyword(s):  
Acetic Acid ◽  
1H Nmr ◽  
Dispersion Polymerization ◽  
Chain Transfer ◽  
Triblock Copolymers ◽  
Raft Polymerization ◽  
Selective Solvent ◽  
Self Assembling ◽  
Reversible Addition ◽  
Large Compound

Diverse nanostructural materials including spheres, nanorods, vesicles, and large compound vesicles have been created via formation of amphiphilic ABA triblock copolymers, self-assembling and morphology transition in the reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization. The polymerization of styrene (St) was performed in a selective solvent, methanol, using S,S′-bis(α,α′-dimethyl-α′′-acetic acid)-trithiocarbonate terminated poly(N,N-dimethylacrylamide) (PDMAa-TC) as macro chain transfer agent and stabilizer, and 1H NMR, and TEM were used to monitor the polymerization.

Preparation of ABC triblock copolymers of N-alkyl substituted acrylamides by RAFT polymerization

2007 ◽  
Vol 85 (6) ◽  
pp. 407-411 ◽  
Author(s):  
Ya Cao ◽  
X X Zhu
Keyword(s):  
Block Copolymers ◽  
Propionic Acid ◽  
Chain Transfer ◽  
Triblock Copolymers ◽  
Raft Polymerization ◽  
Synthetic Pathway ◽  
Abc Triblock Copolymers ◽  
Alkyl Groups ◽  
Reversible Addition ◽  
Acrylamide Monomers

Reversible addition-fragmentation chain transfer (RAFT) polymerization of N-alkyl substituted acrylamides has been carried out by the use of a trithiocarbonate (2-dodecylsulfanylthiocarbonyl-sulfanyl-2-methyl propionic acid) as the RAFT reagent. The N-alkyl groups of the acrylamide monomers are important in the RAFT process. N-alkyl monosubstituted polyacrylamides are found to be active macro-chain transfer agents, while N,N-disubstituted monomers can react easily with them to form a sequent block. We have designed a synthetic pathway to successfully prepare ABC triblock copolymers of N-alkyl substituted acrylamides with low polydispersities (PDI < 1.20) by a three-step RAFT polymerization process.Key words: block copolymers, RAFT polymerization, N-alkyl substituted acrylamides, thermosensitive polymers.

Self-Healing Hydrophobic POSS-functionalized Fluorinated Copolymer via RAFT Polymerization and dynamic Diels-Alder Reaction

2021 ◽  
Author(s):  
Siva Ponnupandian ◽  
Prantik Mondal ◽  
Thomas Becker ◽  
Richard Hoogenboom ◽  
Andrew B Lowe ◽  
...  
Keyword(s):  
Chain Transfer ◽  
Raft Polymerization ◽  
Alder Reaction ◽  
Diels Alder ◽  
Self Healing ◽  
Diels Alder Reaction ◽  
Reversible Addition

This investigation reports the preparation of a tailor-made copolymer of furfuryl methacrylate (FMA) and trifluoroethyl methacrylate (TFEMA) via reversible addition-fragmentation chain transfer (RAFT) polymerization. The furfuryl groups of the copolymer...

scholarly journals Nano-Assemblies from Amphiphilic PnBA-b-POEGA Copolymers as Drug Nanocarriers

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1164
Author(s):  
Angeliki Chroni ◽  
Thomas Mavromoustakos ◽  
Stergios Pispas
Keyword(s):  
Molecular Weight ◽  
Chain Transfer ◽  
Raft Polymerization ◽  
Polymeric Nanocarriers ◽  
Reversible Addition ◽  
2D Noesy ◽  
Drug Nanocarriers ◽  
Glycol Methyl Ether ◽  
Different Molecular Weight

The focus of this study is the development of highly stable losartan potassium (LSR) polymeric nanocarriers. Two novel amphiphilic poly(n-butyl acrylate)-block-poly(oligo(ethylene glycol) methyl ether acrylate) (PnBA-b-POEGA) copolymers with different molecular weight (Mw) of PnBA are synthesized via reversible addition fragmentation chain transfer (RAFT) polymerization, followed by the encapsulation of LSR into both PnBA-b-POEGA micelles. Based on dynamic light scattering (DLS), the PnBA30-b-POEGA70 and PnBA27-b-POEGA73 (where the subscripts denote wt.% composition of the components) copolymers formed micelles of 10 nm and 24 nm in water. The LSR-loaded PnBA-b-POEGA nanocarriers presented increased size and greater mass nanostructures compared to empty micelles, implying the successful loading of LSR into the inner hydrophobic domains. A thorough NMR (nuclear magnetic resonance) characterization of the LSR-loaded PnBA-b-POEGA nanocarriers was conducted. Strong intermolecular interactions between the biphenyl ring and the butyl chain of LSR with the methylene signals of PnBA were evidenced by 2D-NOESY experiments. The highest hydrophobicity of the PnBA27-b-POEGA73 micelles contributed to an efficient encapsulation of LSR into the micelles exhibiting a greater value of %EE compared to PnBA30-b-POEGA70 + 50% LSR nanocarriers. Ultrasound release profiles of LSR signified that a great amount of the encapsulated LSR is strongly attached to both PnBA30-b-POEGA70 and PnBA27-b-POEGA73 micelles.

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.

Living Radical Polymerization with Reversible Addition−Fragmentation Chain Transfer (RAFT Polymerization) Using Dithiocarbamates as Chain Transfer Agents

1999 ◽  
Vol 32 (21) ◽  
pp. 6977-6980 ◽  
Author(s):  
Roshan T. A. Mayadunne ◽  
Ezio Rizzardo ◽  
John Chiefari ◽  
Yen Kwong Chong ◽  
Graeme Moad ◽  
...  
Keyword(s):  
Radical Polymerization ◽  
Chain Transfer ◽  
Raft Polymerization ◽  
Living Radical Polymerization ◽  
Reversible Addition ◽  
Transfer Agents
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