scholarly journals Atom transfer radical polymerization in aqueous dispersed media

2009 ◽  
Vol 7 (4) ◽  
pp. 657-674 ◽  
Author(s):  
Ke Min ◽  
Krzysztof Matyjaszewski

AbstractDuring the last decade, atom transfer radical polymerization (ATRP) received significant attention due to its exceptional capability of synthesizing polymers with pre-determined molecular weight, well-defined molecular architectures and various functionalities. It is economically and environmentally attractive to adopt ATRP to aqueous dispersed media, although the process is challenging. This review summarizes recent developments of conducting ATRP in aqueous dispersed media. The issues related to retaining “controlled/living” character as well as colloidal stability during the polymerization have to be considered. Better understanding the ATRP mechanism and development of new initiation techniques, such as activators generated by electron transfer (AGET) significantly facilitated ATRP in aqueous systems. This review covers the most important progress of ATRP in dispersed media from 1998 to 2009, including miniemulsion, microemulsion, emulsion, suspension and dispersed polymerization.

2009 ◽  
Vol 24 (5) ◽  
pp. 1880-1885 ◽  
Author(s):  
Hou Chen ◽  
Yanfeng Meng ◽  
Ying Liang ◽  
Zixuan Lu ◽  
Pingli Lv

Reverse atom transfer radical polymerization of methacrylonitrile (MAN) initiated by azobisisobutyronitrile (AIBN) was approached for the first time in the absence of any ligand in four novel ionic liquids, 1-methylimidazolium acetate ([mim][AT]), 1-methylimidazolium butyrate ([mim][BT]), 1-methylimidazolium caproate ([mim][CT]), and 1-methylimidazolium heptylate ([mim][HT]). The polymerization in [mim][AT] not only showed the best control of molecular weight and its distribution but also provided a more rapid reaction rate with the ratio of [MAN]:[FeCl3]:[AIBN] at 300:2:1. The block copolymer PMAN-b-PSt was obtained via a conventional ATRP process in [mim][AT] by using the resulting PMAN as a macroinitiator. After simple purification, [mim][AT] and FeCl3 could be easily recycled and reused and had no effect on the living nature of reverse atom transfer radical polymerization of MAN.


2018 ◽  
Vol 3 (3) ◽  
pp. 496-508 ◽  
Author(s):  
Haichen Li ◽  
Christopher R. Collins ◽  
Thomas G. Ribelli ◽  
Krzysztof Matyjaszewski ◽  
Geoffrey J. Gordon ◽  
...  

Combination of deep reinforcement learning and atom transfer radical polymerization gives precise in silico control on polymer molecular weight distributions.


2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Syed Shahabuddin ◽  
Fatem Hamime Ismail ◽  
Sharifah Mohamad ◽  
Norazilawati Muhamad Sarih

Here we describe a simple route to synthesize three-arm star-branched polystyrene. Atom transfer radical polymerization technique has been utilized to yield branched polystyrene involving Williamson coupling strategy. Initially a linear polymeric chain of predetermined molecular weight has been synthesized which is further end-functionalized into a primary alkyl bromide moiety, a prime requisition for Williamson reaction. The end-functionalized polymer is then coupled using 1,1,1-tris(4-hydroxyphenyl)ethane, a trifunctional core molecule, to give well-defined triple-arm star-branched polystyrene.


2012 ◽  
Vol 32 (4-5) ◽  
pp. 235-243 ◽  
Author(s):  
Khezrollah Khezri ◽  
Vahid Haddadi-Asl ◽  
Hossein Roghani-Mamaqani ◽  
Mehdi Salami-Kalajahi

Abstract A newly developed initiation system, activators regenerated by electron transfer (ARGET), was employed to synthesize polystyrene-organoclay nanocomposites via atom transfer radical polymerization (ATRP). ARGET ATRP was applied since it is carried out at significantly low concentrations of the catalyst and environmentally acceptable reducing agents. Conversion and molecular weight evaluations were performed using gravimetry and size exclusion chromatography (SEC), respectively. According to the findings, addition of clay content resulted in a decrease in conversion and molecular weight of nanocomposites. However, an increase of polydispersity index is observed by increasing nanoclay loading. The living nature of the polymerization is revealed by 1H NMR spectroscopy and extracted data from the SEC traces. X-ray diffraction (XRD) analysis shows that organoclay layers are disordered and delaminated in the polymer matrix and exfoliated morphology is obtained. Thermogravimetric analysis (TGA) shows that thermal stability of the nanocomposites is higher than the neat polystyrene. A decrease in glass transition temperature of the samples by increasing organoclay content is observed by differential scanning calorimetry (DSC). Transmission electron microscopy (TEM) reveals that clay layers are partially exfoliated in the polymer matrix containing 2 wt% of organomodified montmorillonite (PSON 2) and a dispersion of partially exfoliated clay stacks is formed.


2004 ◽  
Vol 37 (17) ◽  
pp. 6376-6384 ◽  
Author(s):  
Abdeslam El Harrak ◽  
Géraldine Carrot ◽  
Julian Oberdisse ◽  
Christophe Eychenne-Baron ◽  
François Boué

2019 ◽  
Vol 89 (23-24) ◽  
pp. 5177-5186
Author(s):  
Chung-Feng Jeffrey Kuo ◽  
Jiong-Bo Chen ◽  
Po-Yen Chen ◽  
Garuda Raka Satria Dewangga

Adhesives, such as hot-melt adhesives (HMAs), are widely used in the textile industry for bonding layers of materials and have replaced traditional sewing methods. The block copolymer is a common type of HMA that provides excellent physical features and mechanical properties compared with others. Acrylate-based monomers, methyl methacrylate (MMA), and 2-ethylhexyl acrylate (2-EHA) were used as ingredients to form a linear block copolymer using atom transfer radical polymerization. MMA provides excellent cohesive strength, while 2-EHA provides good adhesion properties. An end-brominated poly(methyl methacrylate) (PMMA-Br) macroinitiator was synthesized from a MMA monomer and initiator, with the best composition obtained by the addition of a 0.6 mol initiator. The macroinitiator had the lowest molecular weight with highest conversion (97%). The addition of a 0.3 mol macroinitiator showed the lowest molecular weight with the highest conversion of acrylic copolymer PMMA- b-poly(2-ethylhexyl acrylate) (PEHA). The glass transition temperature increased with the addition of the macroinitiator concentration, from −43.7℃ to −37.6℃. The thermal stability was reduced with the addition of macroinitiator content, from 332.37℃ to 286.81℃. The shear strength and peel strength of the PMMA- b-PEHA HMAs on nylon fabrics were enhanced from 11.24 to 16.92 kg cm−2 and from 0.29 to 0.61 kg cm−1, respectively, and did not change significantly after being washed 50 times and then kept in low-temperature storage, with the addition of the macroinitiator concentration. The block copolymer PMMA- b-PEHA prepared in this study could be used as a HMA for nylon fabric bonding systems.


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