Preparation of Antimicrobial PHEMA-g-PCBMAE Hydrogels with Improved Mechanical Properties

A series of poly (hydroxyethyl methacrylate)-g-polycarboxybetaine methacrylate ester (PHEMA-g-PCBMAE) hydrogels were synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization in the presence of crosslinker. Then differential scanning calorimetry (DSC) was used to characterize PHEMA-g-PCBMAE hydrogels. The compression stresses of these hydrogels were investigated to evaluate the mechanical properties. The mechanical study suggested that PHEMA-g-PCBMAE hydrogels presented improved mechanical strengths comparing with polycarboxybetaine methacrylate ester (PCBMAE) hydrogel. Besides, the antimicrobial properties of PHEMA-g-PCBMAE hydrogels also estimated by usingStaphylococcus aureusas a model bacterial.

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Controlling Mechanical Properties of 3D Printed Polymer Composites through Photoinduced Reversible Addition-Fragmentation Chain Transfer (RAFT) Polymerization

Polymer Chemistry ◽

10.1039/d1py01283e ◽

2021 ◽

Author(s):

Xiaobing Shi ◽

Jin Zhang ◽

Nathaniel Alan Corrigan ◽

Cyrille Boyer

Keyword(s):

Mechanical Properties ◽

Silica Nanoparticles ◽

Polymer Composites ◽

Chain Transfer ◽

Raft Polymerization ◽

Polymer Networks ◽

Material Design ◽

Advanced Material ◽

Reversible Addition ◽

3D Printed

Reversible addition-fragmentation chain-transfer (RAFT) polymerization has been widely exploited to produce homogeneous and living polymer networks for advanced material design. In this work, we incorporate silica nanoparticles (SNPs) into a...

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RAFT Polymerization of Monomers with Highly Disparate Reactivities: Use of a Single RAFT Agent and the Synthesis of Poly(styrene-block-vinyl acetate)

Australian Journal of Chemistry ◽

10.1071/ch13375 ◽

2013 ◽

Vol 66 (12) ◽

pp. 1564 ◽

Cited By ~ 15

Author(s):

Lily A. Dayter ◽

Kate A. Murphy ◽

Devon A. Shipp

Keyword(s):

Block Copolymers ◽

Vinyl Acetate ◽

Chain Transfer ◽

Raft Polymerization ◽

Good Control ◽

Scanning Calorimetry ◽

Styrene Polymerization ◽

Reversible Addition ◽

Raft Agent ◽

End Group

A single reversible addition–fragmentation chain transfer (RAFT) agent, malonate N,N-diphenyldithiocarbamate (MDP-DTC) is shown to successfully mediate the polymerization of several monomers with greatly differing reactivities in radical/RAFT polymerizations, including both vinyl acetate and styrene. The chain transfer constants (Ctr) for MDP-DTC for both these monomers were evaluated; these were found to be ~2.7 in styrene and ~26 in vinyl acetate, indicating moderate control over styrene polymerization and good control of vinyl acetate polymerization. In particular, the MDP-DTC RAFT agent allowed for the synthesis of block copolymers of these two monomers without the need for protonation/deprotonation switching, as has been previously developed with N-(4-pyridinyl)-N-methyldithiocarbamate RAFT agents, or other end-group transformations. The thermal properties of the block copolymers were studied using differential scanning calorimetry, and those with sufficiently high molecular weight and styrene composition appear to undergo phase separation. Thus, MDP-DTC may be useful for the production of other block copolymers consisting of monomers with highly dissimilar reactivities.

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Synthesis and Characterization of Poly (2-hydroxyethyl methacrylate) Homopolymer at Room Temperature via Reversible Addition–Fragmentation Chain Transfer (RAFT) Polymerization Technique

GAZI UNIVERSITY JOURNAL OF SCIENCE ◽

10.35378/gujs.555136 ◽

2020 ◽

Vol 33 (1) ◽

pp. 22-29

Author(s):

Ertan YİLDİRİM

Keyword(s):

Room Temperature ◽

Chain Transfer ◽

Raft Polymerization ◽

Synthesis And Characterization ◽

Hydroxyethyl Methacrylate ◽

Reversible Addition

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Synthesis and characterization of poly(vinyl chloride-graft-2-vinylpyridine) graft copolymers using a novel macroinitiator by reversible addition-fragmentation chain transfer polymerization

e-Polymers ◽

10.1515/epoly-2013-0011 ◽

2014 ◽

Vol 14 (1) ◽

pp. 27-34 ◽

Cited By ~ 22

Author(s):

Temel Öztürk ◽

Melahat Göktaş ◽

Bedrettin Savaş ◽

Mustafa Işıklar ◽

Mehmet Nuri Atalar ◽

...

Keyword(s):

Vinyl Chloride ◽

Chain Transfer ◽

Raft Polymerization ◽

Graft Copolymers ◽

Monomer Concentration ◽

Polymerization Reaction ◽

Scanning Calorimetry ◽

H Nmr ◽

Poly Vinyl Chloride ◽

Reversible Addition

AbstractSynthesis of poly(vinyl chloride-graft-2-vinylpyridine) graft copolymers was carried out by reversible addition-fragmentation chain transfer (RAFT) polymerization of 2-vinylpyridine using a novel macroinitiator (RAFT macroinitiator). For this purpose, RAFT macroinitiator was obtained from the potassium salt of ethyl xanthogenate and poly(vinyl chloride) (PVC). Then the graft copolymers were synthesized by using RAFT macroinitiator and 2-vinylpyridine. The principal parameters such as monomer concentration, initiator concentration, and polymerization time that affect the polymerization reaction were studied. The effect of the reaction conditions on the heterogeneity index and molecular weight was also investigated. The block lengths of the graft copolymers were calculated by using 1H nuclear magnetic resonance (1H NMR) spectra. The block lengths of the copolymers could be adjusted by varying the monomer and initiator concentrations. The characterizations of the samples were carried out by using 1H NMR, Fourier-transform infrared spectroscopy, gel-permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, and fractional precipitation (γ value) techniques. RAFT polymerization is used to control the polymerization of 2-vinylpyridine over a broad range of molecular weights.

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Removal of Trithiocarbonyl End Group of RAFT-Polymerized Poly(stearyl acrylate) and Effect of the End Group on Thermal and Structural Properties

Polymers ◽

10.3390/polym13234169 ◽

2021 ◽

Vol 13 (23) ◽

pp. 4169

Author(s):

Eri Oishi ◽

Masumi Takamura ◽

Tatsuhiro Takahashi

Keyword(s):

Structural Properties ◽

Alkyl Group ◽

Chain Transfer ◽

Raft Polymerization ◽

Radical Reaction ◽

Scanning Calorimetry ◽

Molecular Weights ◽

Reversible Addition ◽

A Chain ◽

End Group

The effect of a long alkyl end group on the thermal and structural properties of RAFT (reversible addition-fragmentation chain transfer)-polymerized poly(stearyl acrylate) (PSA) was investigated. RAFT-polymerized PSA was prepared using 2-cyano-2-[(dodecylsulfanylthiocarbonyl) sulfanyl] propane (CDTP) with long alkyl group as a chain transfer agent and azobisisobutyronitrile (AIBN) as an initiator. The RAFT polymerization resulted in the polymerized structure having trithiocarbonyl (TTC) at one end and isobutyronitrile at the other end. RAFT-polymerized PSA was prepared with two different molecular weights. The TTC end group was replaced by isobutyronitrile using radical reaction with AIBN through optimization of the conditions, which resulted in isobutyronitrile at both ends. The effect of the end group on the thermal and structural properties was investigated using differential scanning calorimetry and X-ray diffraction, and the results indicated that the long alkyl group from TTC lowers the melting point and semi-crystalline structure in the case of low molecular weight PSA.

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

Polymer Chemistry ◽

10.1039/d0py01522a ◽

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...

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

Polymers ◽

10.3390/polym13071164 ◽

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.

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Research on compatibility and surface of high impact bio-based polyamide

High Performance Polymers ◽

10.1177/09540083211005511 ◽

2021 ◽

pp. 095400832110055

Author(s):

Yang Wang ◽

Yuhui Zhang ◽

Yuhan Xu ◽

Xiucai Liu ◽

Weihong Guo

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Differential Scanning Calorimetry ◽

Crystallization Behavior ◽

High Impact ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Scanning Electron

The super-tough bio-based nylon was prepared by melt extrusion. In order to improve the compatibility between bio-based nylon and elastomer, the elastomer POE was grafted with maleic anhydride. Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis (TGA) were used to study the compatibility and micro-distribution between super-tough bio-based nylon and toughened elastomers. The results of mechanical strength experiments show that the 20% content of POE-g-MAH has the best toughening effect. After toughening, the toughness of the super-tough nylon was significantly improved. The notched impact strength was 88 kJ/m2 increasing by 1700%, which was in line with the industrial super-tough nylon. X-ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to study the crystallization behavior of bio-based PA56, and the effect of bio-based PA56 with high crystallinity on mechanical properties was analyzed from the microstructure.

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

Canadian Journal of Chemistry ◽

10.1139/v10-134 ◽

2011 ◽

Vol 89 (3) ◽

pp. 317-325 ◽

Cited By ~ 10

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.

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