Grafting Poly(methyl methacrylate) onto Polyimide Nanofibers via “Click” Reaction

2009 ◽  
Vol 1 (12) ◽  
pp. 2804-2811 ◽  
Author(s):  
Zhenjun Chang ◽  
Yuan Xu ◽  
Xin Zhao ◽  
Qinghua Zhang ◽  
Dajun Chen
2015 ◽  
Vol 6 (19) ◽  
pp. 3601-3607 ◽  
Author(s):  
Yasuhiro Kohsaka ◽  
Kazuki Yamamoto ◽  
Tatsuki Kitayama

Stereoregular PMMAs carrying an orthogonally double-clickable end, for thiol–ene and azide–alkyne cycloadditions, were prepared via termination with propargyl α-(chloromethyl)acrylate.


2011 ◽  
Vol 64 (4) ◽  
pp. 433 ◽  
Author(s):  
Ming Chen ◽  
Graeme Moad ◽  
Ezio Rizzardo

It has been found that diazomethane undergoes a facile 1,3‐dipolar cycloaddition with both dithiobenzoate RAFT agents and the dithiobenzoate end‐groups of polymers formed by RAFT polymerization. Thus, 2‐cyanoprop‐2‐yl dithiobenzoate on treatment with diazomethane at room temperature provided a mixture of stereoisomeric 1,3‐dithiolanes in near quantitative (>95%) yield. A low‐molecular‐weight RAFT‐synthesized poly(methyl methacrylate) with dithiobenzoate end‐groups underwent similar reaction as indicated by immediate decolourization and a quantitative doubling of molecular weight. Higher‐molecular‐weight poly(methyl methacrylate)s were also rapidly decolourized by diazomethane and provided a product with a bimodal molecular weight distribution. Under similar conditions, the trithiocarbonate group does not react with diazomethane.


2019 ◽  
Vol 9 (3) ◽  
pp. 603 ◽  
Author(s):  
Wenzhong Ma ◽  
Yuchen Zhao ◽  
Zhiwei Zhu ◽  
Lingxiang Guo ◽  
Zheng Cao ◽  
...  

An efficient synthesis route was developed for the preparation of multiwalled carbon nanotube (MWCNT) nanohybrids using azide-terminated poly(methyl methacrylate) (PMMA) via a combination of reversible addition fragmentation chain transfer (RAFT) and the click reaction. A novel azido-functionalized chain transfer agent (DMP-N3) was prepared and subsequently employed to mediate the RAFT polymerizations of methyl methacrylate (MMA). The RAFT polymerizations exhibited first-order kinetics and a linear molecular weight dependence with the conversion. The kinetic results show that the grafting percentage of PMMA on the MWCNTs surface grows along with the increase of the reaction time. Even at 50 °C, the grafting rate of azide-terminated PMMA is comparatively fast in the course of the click reaction, with the alkyne groups adhered to MWCNTs in less than 24 h. The successful functionalization of PMMA onto MWCNT was proved by FTIR, while TGA was employed to calculate the grafting degree of PMMA chains (the highest GP = 21.9%). Compared with the pristine MWCNTs, a thicker diameter of the MWCNTs-g-PMMA was observed by TEM, which confirmed the grafted PMMA chain to the surface of nanotubes. Therefore, the MWCNTs-g-PMMA could be dispersed and stably suspended in water.


2016 ◽  
Vol 7 (29) ◽  
pp. 4842-4851 ◽  
Author(s):  
Peng-Yun Li ◽  
Wei-Dong He ◽  
Sheng-Qi Chen ◽  
Xiao-Xia Lu ◽  
Jia-Min Li ◽  
...  

Well-defined hyperbranched PMMA almost without self-cyclization was obtained through a click reaction, facilitated by a high concentration, good solvent and disubstituted chain ends.


2007 ◽  
Vol 60 (6) ◽  
pp. 400 ◽  
Author(s):  
Patricia L. Golas ◽  
Nicolay V. Tsarevsky ◽  
Brent S. Sumerlin ◽  
Lynn M. Walker ◽  
Krzysztof Matyjaszewski

Multisegmented block copolymers were prepared by the step-growth click coupling of well-defined block copolymers synthesized by atom transfer radical polymerization (ATRP). α,ω-Diazido-terminated polystyrene-block-poly(ethylene oxide)-block-polystyrene was coupled with propargyl ether in N,N-dimethylformamide in the presence of a CuBr/N,N,N´,N´´,N´´-pentamethyldiethylenetriamine catalyst. The preparation of multisegmented block copolymers was also demonstrated by the click coupling of propargyl ether with another diazido-terminated triblock copolymer, poly(n-butyl acrylate)-block-poly(methyl methacrylate)-block-poly(n-butyl acrylate), and a diazido-terminated pentablock copolymer, polystyrene-block-poly(n-butyl acrylate)-block-poly(methyl methacrylate)-block-poly(n-butyl acrylate)-block-polystyrene. The formation of a product of higher molecular weight and broader molecular weight distribution was verified by triple-detection size exclusion chromatography, which revealed that typically five to seven block copolymers were linked together during the click reaction. Differential scanning calorimetry and dynamic mechanical analysis revealed that the amphiphilic block copolymer behaves as a viscoelastic fluid, while its corresponding multiblock copolymer is an elastic material. The multisegmented block copolymers with partially miscible segments exhibit higher glass transition temperatures than their precursors.


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