Avoiding compositional drift during the RAFT copolymerization of N-(2-hydroxypropyl)methacrylamide and N-acryloxysuccinimide: towards uniform platforms for post-polymerization modification

2015 ◽  
Vol 6 (17) ◽  
pp. 3245-3251 ◽  
Author(s):  
John Moraes ◽  
Ioana-Maria Simionca ◽  
Hedi Ketari ◽  
Harm-Anton Klok
Keyword(s):  
Feed Ratio ◽  
Hydroxypropyl Methacrylamide ◽  
Monomer Feed ◽  
Monomer Feed Ratio

Compositionally uniform copolymers: avoiding compositional drift during RAFT copolymerization by controlling monomer feed ratio and conversion.

Synthesis, characterisation and properties of aramid copolymers prepared from AB and AB2 monomers

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Orietta Monticelli ◽  
Stefano Fiori ◽  
Alberto Mariani ◽  
Saverio Russo ◽  
Hartmut Komber
Keyword(s):  
Liquid Crystalline ◽  
Reaction Medium ◽  
Aromatic Polyamide ◽  
Degree Of Crystallinity ◽  
Feed Ratio ◽  
Structure Evolution ◽  
Monomer Composition ◽  
Degradation Temperature ◽  
Monomer Feed ◽  
Monomer Feed Ratio

Abstract Aromatic polyamide (aramid) copolymers having a highly branched architecture were prepared by direct polycondensation of an AB2 monomer (5-(4-aminobenzoylamino) isophthalic acid) with an AB monomer (N-(4-aminophenyl)terephthalamic acid). Two synthetic routes have been followed for copolymer preparation, differing from each other in the overall monomer content and the type of salts added to the reaction medium (LiCl or LiCl + CaCl2). Otherwise, both methods used the same conditions and the same condensing agent (triphenyl phosphite). The feed ratio of the monomers affected the copolymer solubility in aprotic polar solvents such as N,N-dimethylformamide, N-methylpyrrolidone and dimethyl sulfoxide. Only high AB2/AB monomer ratios allowed obtaining completely soluble polymers in the above media. Also copolymer intrinsic viscosity was influenced by that ratio as well as by the polymerisation routes. IR measurements gave an indication of polymer structure evolution as a function of the monomer feed ratio, while 1H NMR experiments verified the actual monomer composition in the synthesized polymers. The monomer feed ratio turned out to influence polymer properties, such as degree of crystallinity, thermal degradation temperature and liquid crystalline behaviour. Some of the characterisation techniques we used (1H and 31P NMR, IR, SEM-EDS) revealed the presence of phosphorus derivatives in the copolymers, despite extensive sample purification. This presence is coming from derivatives of the condensing agent, and is directly related to the content of AB2-type structures present in the copolymers.

The growth and chemical structure of thin photonic films formed from plasma copolymerization: I. Effect of monomer feed ratio

Polymer ◽  
2004 ◽  
Vol 45 (25) ◽  
pp. 8475-8483 ◽  
Author(s):  
H. Jiang ◽  
J.T. Grant ◽  
S. Tullis ◽  
K. Eyink ◽  
P. Fleitz ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Feed Ratio ◽  
Monomer Feed ◽  
Plasma Copolymerization ◽  
Monomer Feed Ratio

Self-doped N-4-sulfopropylaniline–3, 4-ethylenedioxythiophene copolymers

2016 ◽  
Vol 29 (8) ◽  
pp. 976-983 ◽  
Author(s):  
Isao Yamaguchi ◽  
Masaru Ito
Keyword(s):  
Electrical Conductivity ◽  
Electrochemical Oxidation ◽  
Visible Spectrum ◽  
Ammonium Persulfate ◽  
Feed Ratio ◽  
Molar Ratios ◽  
Monomer Feed ◽  
Monomer Feed Ratio

Polymerization of N-4-sulfopropylaniline with 3,4-ethylenedioxythiophene (EDOT) in several molar ratios using ammonium persulfate yielded copolymers (PPrSO3H) consisting of N-4-sulfopropylaminophenylene (unit A) and 3,4-ethylenedioxythiophene-2,5-diyl (unit B). The corresponding copolymers (PBu) consisting of N-butylaminophenylene (unit C) and unit B were synthesized by the reaction of N-butylaniline and EDOT. The content of units A, B, and C in the copolymers depended on the monomer feed ratio. The ultraviolet–visible spectrum of PPrSO3H exhibited absorption peaks at approximately 420 nm and above 850 nm assignable, respectively, to polaron and bipolaron bands. The copolymers were subjected to electrochemical oxidation, which was dependent on the contents of units A and C. The electrical conductivity of PPrSO3H was found to be higher than that of PBu.

scholarly journals The First Synthesis of Periodic and Alternating Glycopolymers by RAFT Polymerization: A Novel Synthetic Pathway for Glycosaminoglycan Mimics

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 70 ◽  
Author(s):  
Masahiko Minoda ◽  
Tomomi Otsubo ◽  
Yohei Yamamoto ◽  
Jianxin Zhao ◽  
Yoshitomo Honda ◽  
...  
Keyword(s):  
Chain Transfer ◽  
Binding Assay ◽  
Raft Polymerization ◽  
Lectin Binding ◽  
Feed Ratio ◽  
Controlled Synthesis ◽  
Reversible Addition ◽  
Monomer Feed ◽  
Polymerization Condition ◽  
Monomer Feed Ratio

This study concerned the controlled synthesis of periodic glycopolymers by reversible addition-fragmentation chain transfer (RAFT) copolymerization. To this end, maltose- and lactose-substituted vinyl ethers (MalVE and LacVE, respectively) and maltose-substituted maleimide (MalMI) were newly synthesized. RAFT copolymerization of MalVE and ethyl maleimide (EtMI) (monomer feed ratio: MalVE:EtMI = 1:1) afforded periodic glycopolymers (poly(MalVE-co-EtMI)) consisting of major parts of alternating structure (-(MalVE-EtMI)n-) and a small part of consecutive sequences of EtMI (–EtMI-EtMI-). Occurrence of the latter sequences was caused by the homopolymerizability of maleimide under the present polymerization condition, and the formation of the consecutive sequences of EtMI was successfully suppressed by varying the monomer feed ratio. RAFT copolymerization of LacVE and EtMI was also found to proceed and similarly yielded periodic glycopolymers (poly(LacVE-co-EtMI)). Moreover, RAFT copolymerization of LacVE and MalMI (monomer feed ratio: LacVE:MalMI = 1:1) was performed to give copolymers (poly(LacVE-co-MalMI)) having composition ratio of LacVE/MalMI ≈ 36/64. The resultant periodic glycopolymers poly(MalVE-co-EtMI) and poly(LacVE-co-EtMI) were subjected to lectin binding assay using concanavalin A and peanut agglutinin, exhibiting the glycocluster effect. Moreover, these glycopolymers obtained from the copolymerization of VE and MI were found to be non-cytotoxic.

Electron Transporting Perylene Diimide-Based Random Terpolymers with Variable Co-Monomer Feed Ratio: A Route to All-Polymer-Based Photodiodes

2022 ◽  
Author(s):  
Stefania Aivali ◽  
Peisen Yuan ◽  
Julianna Panidi ◽  
Dimitra G. Georgiadou ◽  
Themis Prodromakis ◽  
...  
Keyword(s):  
Perylene Diimide ◽  
Feed Ratio ◽  
Monomer Feed ◽  
Monomer Feed Ratio

scholarly journals Electrochemical behavior and conductivity measurements of electropolymerized selenophene-based copolymers

2015 ◽  
Vol 33 (1) ◽  
pp. 25-35 ◽  
Author(s):  
Fadi Alakhras
Keyword(s):  
Cyclic Voltammetry ◽  
Electrolyte Solution ◽  
Electrochemical Behavior ◽  
Electrode Potential ◽  
Redox Activity ◽  
Feed Ratio ◽  
Conductivity Measurements ◽  
Electrochemical Copolymerization ◽  
Monomer Feed ◽  
Monomer Feed Ratio

AbstractElectrochemical copolymerization of selenophene and thiophene was performed at a constant electrode potential. The obtained homopolymer films and copolymers were studied and characterized with cyclic voltammetry and conductivity measurements, from which conductivity values around 13.35 S · cm-1 were determined. The influence of the applied electropolymerization potential and the monomer feed ratio of selenophene and thiophene on the copolymers properties was investigated. The obtained copolymers showed good stability of the redox activity in an acetonitrile-based electrolyte solution. At higher polymerization potentials and at higher concentrations of thiophene in the feed, more thiophene units were incorporated into the copolymer chain. The conductivities of the copolymers were between those of homopolymers, implying that oxidation of both monomers was possible and the copolymer chains might accordingly be composed of both selenophene and thiophene units.

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