Iterative step-growth synthesis and degradation of unimolecular polyviologens under mild conditions

2022 ◽  
Author(s):  
Abigail Delawder ◽  
Mark S. Palmquist ◽  
Jovelt M. Dorsainvil ◽  
Nathan D. Colley ◽  
Tiana M. Saak ◽  
...  

An iterative step-growth addition method was used to expedite the gram-scale synthesis of main-chain polyviologens by several days, while also producing the longest main-chain polyviologen (i.e., 26 viologen subunits) reported...

1997 ◽  
Vol 488 ◽  
Author(s):  
L. G. Madrigal ◽  
E. H. Elandaloussi ◽  
C. W. Spangler

AbstractPoly [2,5-thienylene vinylene] (PTV) has been studied extensively over the past decade for both its metallic conductivity behavior upon chemical doping, as well as its interesting third order nonlinear optical properties. PTV oligomers have been synthesized by our group 1, as well as others 2, and the formation of polaron-like radical-cations or bipolaron-like dications by oxidative doping has been demonstrated. In this paper we describe a general synthetic approach to PTV oligomers functionalized for copolymer formation by step-growth reaction.


RSC Advances ◽  
2015 ◽  
Vol 5 (94) ◽  
pp. 77388-77398 ◽  
Author(s):  
Chun Feng ◽  
Wenqiang Yao ◽  
Guolin Lu ◽  
Yongjun Li ◽  
Xiaoyu Huang

A novel perfluorocyclobutyl aryl ether-based amphiphilic ABA triblock copolymers were synthesized via the site transformation strategy using sequential thermal [2π + 2π] step-growth cycloaddition polymerization and ATRP.


2014 ◽  
Vol 50 (73) ◽  
pp. 10665-10668 ◽  
Author(s):  
S. N. G. Tyler ◽  
R. L. Webster

Exploiting the ready cleavage of bulky amides in the presence of a simple nucleophile, a new monomer for step growth polymerisation has been realised. A range of novel polyesters and polyamides have been prepared under mild conditions that allow for efficient recycling and reuse of the amine by-product. The use of a Lewis acid to increase polyester molecular weight is also explored.


2020 ◽  
Vol 24 (9) ◽  
pp. 1010-1017 ◽  
Author(s):  
Ye Sha ◽  
Zhihua Shen ◽  
Huan Jia ◽  
Zhenyang Luo

Ferrocene, the crown of metallocene family, is widely studied as a functional unit in electrochemical and catalytic applications due to its sandwich structure. Ferrocene moieties can be embedded into the polymer backbone, leading to main-chain ferrocenecontaining polymers. These polymeric materials combine the unique functionalities of iron center with the processabilities of polymers. As one of the choice polymerization techniques, acyclic diene metathesis (ADMET) polymerization serves as a versatile method to prepare main-chain ferrocene-containing polymers under mild conditions using α,ω-dienes as monomers. This paper overviews main-chain ferrocene-containing polymers prepared by ADMET polymerization. Advances in the design, synthesis and applications of this class of organometallic monomers and polymers are detailed.


Polymer ◽  
2009 ◽  
Vol 50 (19) ◽  
pp. 4512-4519 ◽  
Author(s):  
Xiaoqiang Xue ◽  
Jian Zhu ◽  
Wei Zhang ◽  
Zhengbiao Zhang ◽  
Xiulin Zhu

Author(s):  
C. Vannuffel ◽  
C. Schiller ◽  
J. P. Chevalier

Recently, interest has focused on the epitaxy of GaAs on Si as a promising material for electronic applications, potentially for integration of optoelectronic devices on silicon wafers. The essential problem concerns the 4% misfit between the two materials, and this must be accommodated by a network of interfacial dislocations with the lowest number of threading dislocations. It is thus important to understand the detailed mechanism of the formation of this network, in order to eventually reduce the dislocation density at the top of the layers.MOVPE growth is carried out on slightly misoriented, (3.5°) from (001) towards , Si substrates. Here we report on the effect of this misorientation on the interfacial defects, at a very early stage of growth. Only the first stage, of the well-known two step growth process, is thus considered. Previously, we showed that full substrate coverage occured for GaAs thicknesses of 5 nm in contrast to MBE growth, where substantially greater thicknesses are required.


Author(s):  
Agung Eddy Suryo Saputro ◽  
Khairil Anwar Notodiputro ◽  
Indahwati A

In 2018, Indonesia implemented a Governor's Election which included 17 provinces. For several months before the Election, news and opinions regarding the Governor's Election were often trending topics on Twitter. This study aims to describe the results of sentiment mining and determine the best method for predicting sentiment classes. Sentiment mining is based on Lexicon. While the methods used for sentiment analysis are Naive Bayes and C5.0. The results showed that the percentage of positive sentiment in 17 provinces was greater than the negative and neutral sentiments. In addition, method C5.0 produces a better prediction than Naive Bayes.


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