Synthesis, Functionalization and Reductive Degradation of Multibrominated Disulfide-containing Hyperbranched Polymers

2012 ◽  
Vol 65 (1) ◽  
pp. 28 ◽  
Author(s):  
Delia-Laura Popescu ◽  
Nicolay V. Tsarevsky
Keyword(s):  
Ethylene Oxide ◽  
Methyl Ether ◽  
Diethylene Glycol ◽  
Chain Transfer ◽  
Alkyl Bromide ◽  
Star Copolymers ◽  
Reductive Degradation ◽  
Reducing Environment ◽  
Fold Excess ◽  
Glycol Methyl Ether

Reductively degradable hyperbranched polymethacrylates with multiple peripheral alkyl bromide groups were synthesized by the azobis(2-isobutyronitrile)-initiated copolymerization of diethylene glycol methyl ether methacrylate or oligo(ethylene oxide) methyl ether methacrylate with the disulfide-containing crosslinker bis(2-methacryloyloxyethyl)disulfide (2.5–10.0 mol-% relative to the monomer) in the presence of carbon tetrabromide (10–40-fold excess relative to the radical initiator) as efficient chain transfer agent. The alkyl bromide groups initiated the atom-transfer radical polymerization of methyl methacrylate, and star copolymers with hyperbranched disulfide-containing cores were formed. Both the macroinitiators and the star copolymers derived from them were degraded in reducing environment.

scholarly journals Facile preparation of hybrid vesicles loaded with silica nanoparticles via aqueous photoinitiated polymerization-induced self-assembly

RSC Advances ◽  
2017 ◽  
Vol 7 (37) ◽  
pp. 23114-23121 ◽  
Author(s):  
Jianbo Tan ◽  
Dongdong Liu ◽  
Xuechao Zhang ◽  
Chundong Huang ◽  
Jun He ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Silica Nanoparticles ◽  
Methyl Ether ◽  
Self Assembly ◽  
Dispersion Polymerization ◽  
Chain Transfer ◽  
Poly Ethylene Glycol ◽  
Facile Preparation ◽  
Poly Ethylene ◽  
Glycol Methyl Ether

We report a photoinitiated dispersion polymerization of 2-hydroxypropyl methacrylate (HPMA) in the presence of silica nanoparticles using a poly(ethylene glycol) methyl ether (mPEG) macromolecular chain transfer agent (macro-CTA).

scholarly journals Effect of Some Oxygenates on the Opacity Level of a DI Diesel Engine with and without DPF

2019 ◽  
Vol 13 (3) ◽  
pp. 35 ◽  
Author(s):  
Jehad A. A. Yamin ◽  
Mohammad Samih Hijazi ◽  
Mohammad A. Hamdan
Keyword(s):  
Diesel Engine ◽  
Propylene Glycol ◽  
Methyl Ether ◽  
Diethylene Glycol ◽  
Maximum Reduction ◽  
Different Types ◽  
Di Diesel Engine ◽  
Glycol Monoethyl Ether ◽  
Diethylene Glycol Monoethyl Ether ◽  
Glycol Methyl Ether

Toyota car fitted with smoke meter to measure the opacity in the exhaust was used. Five different types of oxygenates were used with the concentration of each one varied between 5 to 20% by volume at an increment of 5%. The results show a significant reduction in the opacity of the exhaust products. A maximum of 70% reduction was achieved when 15% ethanol was added at 3000 RPM, and 62% reduction when 20% methanol was added at same speed. As for Dimethoxy Ethane (DMET), a maximum reduction of 30% was achieved at 3000 RPM and that of Tri-propylene glycol methyl ether (TPGME) was 27.3% at same speed. Diethylene glycol monoethyl ether (DGME) did not show encouraging results as a maximum reduction of 10.3% was achieved at 2000 RPM with 5% of DGME. Further, it was found that the reduction in the opacity level was less significant when the filter was used. This, perhaps, is due to the nature of the DPF used.

Nonviral Plasmid DNA Carriers Based on N,N′-Dimethylaminoethyl Methacrylate and Di(ethylene glycol) Methyl Ether Methacrylate Star Copolymers

2015 ◽  
Vol 16 (10) ◽  
pp. 3275-3285 ◽  
Author(s):  
Barbara Mendrek ◽  
Łukasz Sieroń ◽  
Iwona Żymełka-Miara ◽  
Paulina Binkiewicz ◽  
Marcin Libera ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Methyl Ether ◽  
Plasmid Dna ◽  
Dimethylaminoethyl Methacrylate ◽  
Star Copolymers ◽  
Glycol Methyl Ether ◽  
Dna Carriers

Synthesis and photophysical and supramolecular study of π-conjugated (diethylene glycol methyl ether) benzoateethynylene oligomers and polymers

2015 ◽  
Vol 6 (9) ◽  
pp. 1639-1648 ◽  
Author(s):  
D. Meza ◽  
E. Arias ◽  
I. Moggio ◽  
J. Romero ◽  
J. M. Mata ◽  
...  
Keyword(s):  
Methyl Ether ◽  
Diethylene Glycol ◽  
X Ray ◽  
X Ray Scattering ◽  
Glycol Methyl Ether ◽  
Ray Scattering

The strong π–π interaction that governs (diethylene glycol methyl ether) benzoateethynylene macromolecules was evidenced by X-ray scattering and HRTEM.

scholarly journals Synthesis of Michael Acceptor Ionomers of Poly(4-Sulfonated Styrene-co-Poly(ethylene Glycol) Methyl Ether Acrylate)

2009 ◽  
Vol 62 (11) ◽  
pp. 1496 ◽  
Author(s):  
Steevens N. S. Alconcel ◽  
Gregory N. Grover ◽  
Nicholas M. Matsumoto ◽  
Heather D. Maynard
Keyword(s):  
Ethylene Glycol ◽  
Methyl Ether ◽  
Chain Transfer ◽  
Solvent System ◽  
Poly Ethylene Glycol ◽  
Polymer Backbone ◽  
Water Solvent ◽  
Michael Acceptor ◽  
Poly Ethylene ◽  
Glycol Methyl Ether

Ionomers containing sodium 4-styrene sulfonate (4SS) and poly(ethylene glycol) methyl ether acrylate (PEGA) were synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization. The polymerization was mediated by 1-phenylethyl dithiobenzoate chain transfer agent in a dimethylformamide/water solvent system. Well-defined copolymers of pPEGA-co-4SS were produced with molecular weights ranging from 10 to 40 kDa and polydispersity indices of 1.06–1.18 by gel permeation chromatography against monodisperse poly(methyl methacrylate) standards. After polymerization, the dithioester was reduced and trapped in situ with divinyl sulfone to produce a well-defined, semitelechelic pPEGA-co-4SS Michael acceptor polymer. UV-visible, infrared, and 1H NMR spectroscopy confirmed that the integrity of the polymer backbone was maintained and that the vinyl sulfone was successfully incorporated at the chain end.

scholarly journals Tunable Thermo-Responsive Copolymers from DEGMA and OEGMA Synthesized by RAFT Polymerization and the Effect of the Concentration and Saline Phosphate Buffer on its Phase Transition

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1657 ◽  
Author(s):  
Ramírez-Jiménez ◽  
Montoya-Villegas ◽  
Licea-Claverie ◽  
Gónzalez-Ayón
Keyword(s):  
Ethylene Glycol ◽  
Methyl Ether ◽  
Phosphate Buffer ◽  
Chain Transfer ◽  
Average Molecular Weight ◽  
Polymer Composition ◽  
Feed Ratio ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
Glycol Methyl Ether

Thermo-responsive polymers and copolymers derivatives of oligo(ethylene glycol) methyl ether methacrylate (Mn = 300 g mol−1) (OEGMA) and di(ethylene glycol) methyl ether methacrylate (DEGMA) have been synthesized by reversible addition fragmentation chain transfer polymerization (RAFT) using 5-amino-4-methyl-4-(propylthiocarbonothioylthio)-5-oxopentanoic acid (APP) as chain transfer agent (CTA). The monomer conversion was evaluated by hydrogen nuclear magnetic resonance (1H-NMR); number average molecular weights (Mn), weight average molecular weight (Mw), and dispersity (Đ) were obtained by gel permeation chromatography (GPC); glass transition temperature (Tg) was evaluated by modulated differential scanning calorimetry (DSC), cloud point temperature (Tcp) was measured and compared by turbidimetry and dynamic light scattering (DLS). The effect of polymer composition and concentration on the Tcp, either in water or in phosphate buffer saline (PBS), was studied. The values of Tcp using PBS were between 3 and 4 °C lower than using water. Results showed an ideal copolymerization behavior; therefore, the Tcp could be tuned by an adequate monomers feed ratio obtaining polymers which may be used in drug delivery and other applications.

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