Synthesis of Structurally Controlled, Highly Branched Polymethacrylates) by Radical Polymerization Through the Design of a Monomer Having Hierarchical Reactivity

2020 ◽  
Author(s):  
Shigeru Yamago ◽  
Yangtian Lu
Keyword(s):  
Radical Polymerization ◽  
Structural Control ◽  
Theoretical Calculations ◽  
Radical Copolymerization ◽  
Butyl Methacrylate ◽  
Fragmentation Reaction ◽  
Flight Mass Spectrometry ◽  
Ion Mobility Spectroscopy ◽  
Polar Functional Groups ◽  
Branched Structure

The controlled synthesis of highly branched (HB) poly(methyl methacrylate) (PMMA) with a molecular weight of up to 88 × 10<sup>3 </sup>gmol and low dispersity (<i>Ð</i> < 2.0) was achieved by the radical copolymerization of vinyltelluride, H<sub>2</sub>C=CHTePh (<b>4cD</b>), and MMA in the presence of the organotellurium chain transfer agent <b>6cI</b> at 30 °C. Control of the branching structure was suggested by the Mark-Hauwink-Khun-Sakurada plots corresponding to samples in solution and trapped ion mobility spectroscopy-time of flight mass spectrometry in the gas phase. The mechanism of <b>4cD</b> for the structural control of HB-PMMA synthesis comes from the hierarchical reactivity of the C-Te bond of <b>4cD</b>, which serves as the branching point only after <b>4cD</b> reacts and is incorporated into the polymer chain. In contrast, copolymerization using previously reported vinyltellurides <b>4aA</b> (H<sub>2</sub>C=C(Me)TeMe) and <b>4aB</b> (H<sub>2</sub>C=C(Me)-CH=CHTeMe) could not control the branching structure due to the <i>b</i>-carbon fragmentation reaction from the intermediate radicals generated from <b>4aA</b> and <b>4bB</b>. The theoretical calculations suggest that the suppression of the undesired fragmentation reaction when using <b>4cD</b> is due to the acceleration of the desired propagation reaction forming a branched structure instead of decelerating the fragmentation reaction. Due to the versatility of radical polymerization, methacrylates with bulky substituents, such as <i>t</i>-butyl methacrylate, and polar functional groups, such as <i>N,N</i>-dimethylethyl methacrylate (DMAEM), were also used as monomers to afford structurally controlled corresponding HB polymers. These studies clearly open a new possibility for the use of HB polymers in macromolecular engineering.

Synthesis of Structurally Controlled, Highly Branched Polymethacrylates) by Radical Polymerization Through the Design of a Monomer Having Hierarchical Reactivity

2020 ◽  
Author(s):  
Shigeru Yamago ◽  
Yangtian Lu
Keyword(s):  
Radical Polymerization ◽  
Structural Control ◽  
Theoretical Calculations ◽  
Radical Copolymerization ◽  
Butyl Methacrylate ◽  
Fragmentation Reaction ◽  
Flight Mass Spectrometry ◽  
Ion Mobility Spectroscopy ◽  
Polar Functional Groups ◽  
Branched Structure

The controlled synthesis of highly branched (HB) poly(methyl methacrylate) (PMMA) with a molecular weight of up to 88 × 10<sup>3 </sup>gmol and low dispersity (<i>Ð</i> < 2.0) was achieved by the radical copolymerization of vinyltelluride, H<sub>2</sub>C=CHTePh (<b>4cD</b>), and MMA in the presence of the organotellurium chain transfer agent <b>6cI</b> at 30 °C. Control of the branching structure was suggested by the Mark-Hauwink-Khun-Sakurada plots corresponding to samples in solution and trapped ion mobility spectroscopy-time of flight mass spectrometry in the gas phase. The mechanism of <b>4cD</b> for the structural control of HB-PMMA synthesis comes from the hierarchical reactivity of the C-Te bond of <b>4cD</b>, which serves as the branching point only after <b>4cD</b> reacts and is incorporated into the polymer chain. In contrast, copolymerization using previously reported vinyltellurides <b>4aA</b> (H<sub>2</sub>C=C(Me)TeMe) and <b>4aB</b> (H<sub>2</sub>C=C(Me)-CH=CHTeMe) could not control the branching structure due to the <i>b</i>-carbon fragmentation reaction from the intermediate radicals generated from <b>4aA</b> and <b>4bB</b>. The theoretical calculations suggest that the suppression of the undesired fragmentation reaction when using <b>4cD</b> is due to the acceleration of the desired propagation reaction forming a branched structure instead of decelerating the fragmentation reaction. Due to the versatility of radical polymerization, methacrylates with bulky substituents, such as <i>t</i>-butyl methacrylate, and polar functional groups, such as <i>N,N</i>-dimethylethyl methacrylate (DMAEM), were also used as monomers to afford structurally controlled corresponding HB polymers. These studies clearly open a new possibility for the use of HB polymers in macromolecular engineering.

Structural control in radical polymerization with 1,1-diphenylethylene. 1. Copolymerization of 1,1-diphenylethylene with methyl methacrylate

Polymer ◽  
2002 ◽  
Vol 43 (26) ◽  
pp. 7231-7241 ◽  
Author(s):  
Sophie Viala ◽  
Klaus Tauer ◽  
Markus Antonietti ◽  
R.-P Krüger ◽  
Wolfgang Bremser
Keyword(s):  
Methyl Methacrylate ◽  
Radical Polymerization ◽  
Structural Control

Atom Transfer Radical Polymerization of iso-Butyl Methacrylate in Microemulsion with Cationic and Non-Ionic Emulsifiers

2008 ◽  
Vol 29 (3) ◽  
pp. 264-264
Author(s):  
Yasuyuki Kagawa ◽  
Masahiro Kawasaki ◽  
Per B. Zetterlund ◽  
Hideto Minami ◽  
Masayoshi Okubo
Keyword(s):  
Atom Transfer Radical Polymerization ◽  
Radical Polymerization ◽  
Butyl Methacrylate ◽  
Atom Transfer

Preparation of Anion Exchange Membranes Base on Fluoro-Polyacrylate for Alkaline Fuel Cells

2012 ◽  
Vol 485 ◽  
pp. 84-87
Author(s):  
Jun Fang ◽  
Yong Bin Wu ◽  
Yan Mei Zhang
Keyword(s):  
Fuel Cells ◽  
Fuel Cell ◽  
Radical Polymerization ◽  
Anion Exchange ◽  
Butyl Methacrylate ◽  
Anion Exchange Membranes ◽  
Reaction Conditions ◽  
Alkaline Fuel Cells ◽  
Fuel Cell Application ◽  
Potential Applications

A series of hydroxyl conducting anion exchange membranes based on the copolymer of vinylbenzyl chloride, butyl methacrylate and fluoro-polyacrylate were prepared by radical polymerization, quaternization and alkalization. The reaction conditions of polymerization were discussed and the potential applications of the resulting membranes in alkaline fuel cells were assessed. The results show that the membranes have adequate conductivity for fuel cell application.

scholarly journals Effect of Structure of Polymers Grafted from Graphene Oxide on the Compatibility of Particles with a Silicone-Based Environment and the Stimuli-Responsive Capabilities of Their Composites

Nanomaterials ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 591 ◽  
Author(s):  
Monika Zygo ◽  
Miroslav Mrlik ◽  
Marketa Ilcikova ◽  
Martina Hrabalikova ◽  
Josef Osicka ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Graphene Oxide ◽  
Radical Polymerization ◽  
Polymer Brushes ◽  
Silicone Oil ◽  
Polymer Chains ◽  
Butyl Methacrylate ◽  
Raman Shift ◽  
Stimuli Responsive ◽  
Grafted Polymer

This study reports the utilization of controlled radical polymerization as a tool for controlling the stimuli-responsive capabilities of graphene oxide (GO) based hybrid systems. Various polymer brushes with controlled molecular weight and narrow molecular weight distribution were grafted from the GO surface by surface-initiated atom transfer radical polymerization (SI-ATRP). The modification of GO with poly(n-butyl methacrylate) (PBMA), poly(glycidyl methacrylate) (PGMA), poly(trimethylsilyloxyethyl methacrylate) (PHEMATMS) and poly(methyl methacrylate) (PMMA) was confirmed by thermogravimetric analysis (TGA) coupled with online Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Various grafting densities of GO-based materials were investigated, and conductivity was elucidated using a four-point probe method. Raman shift and XPS were used to confirm the reduction of surface properties of the GO particles during SI-ATRP. The contact angle measurements indicated the changes in the compatibility of GOs with silicone oil, depending on the structure of the grafted polymer chains. The compatibility of the GOs with poly(dimethylsiloxane) was also investigated using steady shear rheology. The tunability of the electrorheological, as well as the photo-actuation capability, was investigated. It was shown that in addition to the modification of conductivity, the dipole moment of the pendant groups of the grafted polymer chains also plays an important role in the electrorheological (ER) performance. The compatibility of the particles with the polymer matrix, and thus proper particles dispersibility, is the most important factor for the photo-actuation efficiency. The plasticizing effect of the GO-polymer hybrid filler also has a crucial impact on the matrix stiffness and thus the ability to reversibly respond to the external light stimulation.

scholarly journals Effect of Graphene oxide or Functionalized Graphene Oxide on the Copolymerization Kinetics of Styrene/n-butyl Methacrylate

Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 999 ◽  
Author(s):  
Ioannis Tsagkalias ◽  
Afrodite Vlachou ◽  
George Verros ◽  
Dimitris Achilias
Keyword(s):  
Graphene Oxide ◽  
Radical Copolymerization ◽  
Butyl Methacrylate ◽  
Side Reactions ◽  
Hydroxyl Groups ◽  
Functionalized Graphene ◽  
Functionalized Graphene Oxide ◽  
Molecular Weights ◽  
Diffusion Controlled ◽  
Kinetic Rate Constants

Nanocomposite materials based on copolymers of styrene and n-butyl methacrylate with either graphene oxide (GO) or functionalized graphene oxide (F-GO) were synthesized using the in-situ bulk radical copolymerization technique. Reaction kinetics was studied both experimentally and theoretically using a detailed kinetic model also taking into account the effect of diffusion-controlled phenomena on the reaction kinetic rate constants. It was found that the presence of GO results in lower polymerization rates accompanied by the synthesis of copolymers having higher average molecular weights. In contrast, the presence of F-GO did not seem to significantly alter the conversion vs time curves, whereas it results in slightly lower average molecular weights. The first observation was attributed to side reactions of the initiator primary radicals with the hydroxyl groups on the surface of GO, resulting in lower initiator efficiency, whereas the second to grafted structures formed from copolymer macromolecules on the F-GO surface. The copolymerization model predictions including MWD data were found to be in satisfactory agreement with the experimental data. At least four adjustable parameters were employed and their best-fit values were provided.

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