Direct Observation of Polymerization-Reaction-Induced Molecular Self-Assembling Process:  In-Situ and Real-Time SANS Measurements during Living Anionic Polymerization of Polyisoprene-block-polystyrene

A dual-functionalized sequence-defined terpolymer was synthesized via living anionic polymerization; meanwhile its kinetic characteristics and sequence structure were investigated in detail via the in situ1H NMR method.

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Synthesis and post-polymerization reaction of end-clickable stereoregular polymethacrylates via termination of stereospecific living anionic polymerization

Polymer Chemistry ◽

10.1039/c4py01285b ◽

2015 ◽

Vol 6 (7) ◽

pp. 1078-1087 ◽

Cited By ~ 22

Author(s):

Yasuhiro Kohsaka ◽

Takashi Kurata ◽

Kazuki Yamamoto ◽

Shoya Ishihara ◽

Tatsuki Kitayama

Keyword(s):

Methyl Methacrylate ◽

Anionic Polymerization ◽

Polymerization Reaction ◽

Living Anionic Polymerization ◽

Poly Methyl Methacrylate ◽

End Groups

Poly(methyl methacrylate)s with high stereoregularity and clickable end-groups were synthesized via terminating reactions with α-(halomethyl)acrylates in stereospecific living anionic polymerization.

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Mapping the multi-step mechanism of a photoredox catalyzed atom-transfer radical polymerization reaction by direct observation of the reactive intermediates

Chemical Science ◽

10.1039/d0sc01194k ◽

2020 ◽

Vol 11 (17) ◽

pp. 4475-4481 ◽

Cited By ~ 1

Author(s):

Luke Lewis-Borrell ◽

Mahima Sneha ◽

Aditi Bhattacherjee ◽

Ian P. Clark ◽

Andrew J. Orr-Ewing

Keyword(s):

Atom Transfer Radical Polymerization ◽

Real Time ◽

Radical Polymerization ◽

Absorption Spectroscopy ◽

Direct Observation ◽

Transient Absorption ◽

Reactive Intermediates ◽

Transient Absorption Spectroscopy ◽

Polymerization Reaction ◽

Step Mechanism

Short-lived intermediates are tracked in real-time by transient absorption spectroscopy during a multi-step photoredox catalysed polymerization reaction.

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In-situ Titration of Initiator-Consuming Impurities in Solution Anionic Polymerization

Rubber Chemistry and Technology ◽

10.5254/1.3538331 ◽

1993 ◽

Vol 66 (4) ◽

pp. 588-593 ◽

Cited By ~ 10

Author(s):

V. M. Monroy ◽

G. Guevara ◽

I. Leon ◽

A. Correa ◽

R. Herrera

Keyword(s):

Anionic Polymerization ◽

Polymerization Reaction ◽

Molecular Weights

Abstract An in situ titration of initiator-consuming impurities in amonic polymerizations, using 1,10-phenantroline as an indicator, was developed. The results show that even when impurities are present, it is possible to destroy them prior to the initiation of the polymerization reaction and achieve a better control of molecular weights by adding accurate known quantities of initiator.

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Lithiated Thiaacetals as Initiators for Living Anionic Polymerization of Diene Elastomers: Polymerization and Compounding

Rubber Chemistry and Technology ◽

10.5254/1.3539402 ◽

2007 ◽

Vol 80 (2) ◽

pp. 194-211 ◽

Cited By ~ 1

Author(s):

Terrence E. Hogan ◽

Yuan-Yong Yan ◽

William L. Hergenrother ◽

David F. Lawson

Keyword(s):

Polymer Chain ◽

Anionic Polymerization ◽

Polydispersity Index ◽

Methyl Substituent ◽

Living Anionic Polymerization ◽

Model Studies ◽

Polymerization Mixture ◽

Procedure Model

Abstract Polybutadiene and poly(butadiene-co-styrene) elastomers were prepared in high conversions using 2-lithio-2- methyl-1,3-dithiane as the initiator. Polymers were readily prepared with a polydispersity index (PDI) of 1.05 to 1.26 and a Mn of up to 208 kg/mol. The replacement of the 2-methyl substituent with phenyl, trimethylsilyl or 4-dimethylamino phenyl also gave active initiators that incorporated at the head of the chain. However, initiation rates appeared to vary somewhat with the structure of the initiators. The polymerizations obtained are in all cases controlled and apparently living with the live chain ends capable of further reactions. The initiators could be generated prior to addition to the polymerization mixture or by an in-situ procedure. Model studies gave evidence that the dithiane chain end can be opened under cure conditions and react with unsaturation present in the polymer chain. Several of the product polymers were found to impart improved hysteresis to carbon and silica-filled rubbery vulcanizates possibly through an endlinking mechanism.

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In Situ Real-time Confocal Imaging of a Self-assembling Peptide-grafted Polymer Showing pH-responsive Hydrogelation

Chemistry Letters ◽

10.1246/cl.200513 ◽

2020 ◽

Vol 49 (11) ◽

pp. 1319-1323

Author(s):

Ryou Kubota ◽

Shogo Torigoe ◽

Shuang Liu ◽

Itaru Hamachi

Keyword(s):

Real Time ◽

Confocal Imaging ◽

Ph Responsive ◽

Grafted Polymer ◽

Self Assembling

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Direct Kinetic Measurements of Vinyl Polymerization on Metal and Silicon Surfaces Using Real-Time FT-IR Spectroscopy

Applied Spectroscopy ◽

10.1366/0003702934067739 ◽

1993 ◽

Vol 47 (9) ◽

pp. 1425-1429 ◽

Cited By ~ 19

Author(s):

D. Billy Yang

Keyword(s):

Real Time ◽

Anionic Polymerization ◽

High Surface ◽

Degree Of Polymerization ◽

Silicon Surfaces ◽

Polymerization Reaction ◽

Kinetic Measurements ◽

Vinyl Polymerization ◽

Polymerization Kinetic ◽

Ft Ir

A real-time FT-IR (RT/FT-IR) technique has been used to perform direct kinetic measurements of vinyl polymerization on metal and silicon surfaces. Here, we are reporting our results in studies of anaerobic and photo-induced anionic polymerizations of monomers containing vinyl functional groups (>C=C<) for adhesive and coating applications. For anaerobic polymerization we are investigating the hydroperoxide-initiated free radical polymerization of model multifunctional methacrylate monomer systems. We will report the results of our studies on the catalytic effects of different dithiolate complexes and related accelerators. In photo-induced anionic polymerization we will report our studies for ethyl cyanoacrylate (CA) polymerization initiated by a controlled release of anion from a stable chromium complex precursor ( trans-Cr-(NH3)2(NCS)4−K+). Because of high surface sensitivity of the CA monomer, the polymerization kinetic studies were performed on a clean silicon surface at room temperature. The effect of the initiator concentration and irradiation wavelengths on polymerization kinetic rate will be discussed. The acrylic polymerization was monitored with the use of the C=C stretching band at 1634 and 1627 cm−1 for polyglycol dimethacrylate and cyanoacrylate, respectively. Both the degree of polymerization and the intrinsic rates of the polymerization reactions were calculated for kinetic comparisons. For anaerobic polymerization studies, GC/FT-IR software was used which provided a real-time screen display of IR spectral changes as the reaction proceeded. For very fast cyanoacrylate anionic polymerization studies, new FT-IR kinetic software was used to collect 204 spectra per minute with one spectrum per scan. In this case, the interferograms were collected first; post-Fourier transform conversion and spectral script reduction were then performed. Some detailed experimental techniques and polymerization reaction mechanisms will also be discussed.

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Real-time SANS and 1H-NMR studies during “living” anionic polymerization of butadiene in hydrocarbon media

Physica B Condensed Matter ◽

10.1016/j.physb.2004.03.238 ◽

2004 ◽

Vol 350 (1-3) ◽

pp. E921-E925 ◽

Cited By ~ 4

Author(s):

A.Z Niu ◽

J Stellbrink ◽

J Allgaier ◽

L Willner ◽

D Richter ◽

...

Keyword(s):

Real Time ◽

1H Nmr ◽

Anionic Polymerization ◽

Living Anionic Polymerization ◽

Nmr Studies ◽

Hydrocarbon Media

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Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

10.26434/chemrxiv.7098695 ◽

2018 ◽

Author(s):

Elaine A. Kelly ◽

Judith E. Houston ◽

Rachel Evans

Keyword(s):

Real Time ◽

Absorption Spectroscopy ◽

Self Assembly ◽

Uv Light ◽

Wormlike Micelles ◽

Tetraethylene Glycol ◽

Light Illumination ◽

First Time ◽

Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such asdrug delivery and micellar catalysis. Currently, their behaviour in the equilibrium cis-and trans-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C8AzoOC8E4) using small-angle neutron scattering (SANS). We show that the incorporation of in-situUV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C8AzoOC8E4could switch between wormlike micelles (transnative state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked in-situthrough combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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