scholarly journals Reaction Mechanism and kinetics of In-Situ Polymerization of Pyrrole onto Textiles: A Review

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Subhankar Maity

Research of electro-conductive textiles based on conductive polymers like polypyrrole, has increased in the recent years due to their high potential applications in various field. Conductive polymers behave like insulator in their neutral states with typical electrical conductivity in the range 10-10 to 10-25 Scm-1. These neutral polymers can be converted into semi-conductive or conductive states with conductivities range of 1 Scm-1 to 10-4 Scm-1 through chemical or electro-chemical redox reactions. By the applications of these polymers onto a textile surface, we can be able to obtain novel composites which are strong, flexible, light weight and highly electro-conductive. These textile composites are suitable for applications such as heating pads, sensors, corrosion-protecting materials, actuators, electrochromic devices, EMI shielding etc. The methods of applications of conductive polymers onto the textile surface such as in-situ chemical, in-situ electro-chemical, in-situ vapor phase, in-situ polymerization in a supercritical fluid, solution coating process are described here briefly. Merits and demerits of these methods are mentioned here. Reaction mechanisms of chemical and electro-chemical polymerization proposed by the different researcher are described. Different factors affecting the kinetics of chemical and electro-chemical polymerization are accounted. Influence of textile materials on the kinetics of chemical polymerization is reviewed and reported.

2020 ◽  
Vol 27 (1) ◽  
pp. 204-215
Author(s):  
Hongkai Zhao ◽  
Dengchao Zhang ◽  
Yingshuang Li

AbstractIn this work, we modified nylon 6 with liquid rubber by in-situ polymerization. The infrared analysis suggested that HDI urea diketone is successfully blocked by caprolactam after grafting on hydroxyl of HTPB, and the rubber-modified nylon copolymer is generated by the anionic polymerization. The impact section analysis indicated the rubber-modified nylon 6 resin exhibited an alpha crystal form.With an increase in the rubber content, nylon 6 was more likely to generate stable α crystal. Avrami equation was a good description of the non-isothermal crystallization kinetics of nylon-6 and rubber-modified nylon-6 resin. Moreover, it is found that the initial crystallization temperature of nylon-6 chain segment decreased due to the flexible rubber chain segment. n value of rubber-modified nylon-6 indicated that its growth was the coexistence of two-dimensional discoid and three-dimensional spherulite growth. Finally, the addition of the rubber accelerated the crystallization rate of nylon 6.


Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 474
Author(s):  
Ioannis S. Tsagkalias ◽  
Alexandra Loukidi ◽  
Stella Chatzimichailidou ◽  
Constantinos E. Salmas ◽  
Aris E. Giannakas ◽  
...  

The great concern about the use of hazardous additives in food packaging materials has shown the way to new bio-based materials, such as nanoclays incorporating bioactive essential oils (EO). One of the still unresolved issues is the proper incorporation of these materials into a polymeric matrix. The in situ polymerization seems to be a promising technique, not requiring high temperatures or toxic solvents. Therefore, in this study, the bulk radical polymerization of styrene was investigated in the presence of sodium montmorillonite (NaMMT) and organo-modified montmorillonite (orgMMT) including thyme (TO), oregano (OO), and basil (BO) essential oil. It was found that the hydroxyl groups present in the main ingredients of TO and OO may participate in side retardation reactions leading to lower polymerization rates (measured gravimetrically by the variation of monomer conversion with time) accompanied by higher polymer average molecular weight (measured via GPC). The use of BO did not seem to affect significantly the polymerization kinetics and polymer MWD. These results were verified from independent experiments using model compounds, thymol, carvacrol and estragol instead of the clays. Partially intercalated structures were revealed from XRD scans. The glass transition temperature (from DSC) and the thermal stability (from TGA) of the nanocomposites formed were slightly increased from 95 to 98 °C and from 435 to 445 °C, respectively. Finally, better dispersion was observed when orgMMT was added instead of NaMMT.


2021 ◽  
Author(s):  
Liang Wang ◽  
Peng Gao ◽  
Mengxin Liu ◽  
Ziqing Huang ◽  
Shixia Lan ◽  
...  

Monodisperse polypyrrole/SBA-15 composite (PPy/SBA-15) was fabricated by in-situ polymerization and used for Cr(Ⅵ) adsorption from aqueous solution. PPy/SBA-15 was characterized by numerous approaches. Factors affecting the Cr(Ⅵ) adsorption process included...


2016 ◽  
Vol 47 (8) ◽  
pp. 2228-2252 ◽  
Author(s):  
Subhankar Maity ◽  
Arobindo Chatterjee

This article reviews the preparation, development and characteristics of conductive polymer-based electro-conductive textile composites for electromagnetic interference shielding. Modification of ordinary textile materials in the form of electro-conductive composites makes them suitable for this purpose. Various metallic and non-metallic electro-conductive textiles have been explored here as the material for electromagnetic shielding. Different approaches of preparing textile electromagnetic shield have been described here. Recent advancements of application of conductive polymers in the field of textile electromagnetic shielding are described. Conductive polymer-coated textile materials showed superior electrical property as electromagnetic shield. Different methods of applications of conductive polymers onto textile surface are described here with their relative merits and demerits. Different conductive polymer-coated woven and nonwoven fabrics prepared by various researchers for electromagnetic shielding are taken into account. The effects of different process parameters of polymer processing on electromagnetic shielding are described.


Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 985 ◽  
Author(s):  
Yidong Liu ◽  
Lingfeng Jian ◽  
Tianhua Xiao ◽  
Rongtao Liu ◽  
Shun Yi ◽  
...  

CO2 has been regarded as one of the most promising blowing agents for polystyrene (PS) foam due to its non-flammability, low price, nontoxicity, and eco-friendliness. However, the low solubility and fast diffusivity of CO2 in PS hinder its potential applications. In this study, an attapulgite (ATP)/polypyrrole (PPy) nanocomposite was developed using the in situ polymerization method to generate the hierarchical cell texture for the PS foam based on the supercritical CO2 foaming. The results demonstrated that the nanocomposite could act as an efficient CO2 capturer enabling the random release of it during the foaming process. In contrast to the pure PS foam, the ATP/PPy nanocomposite reinforced PS foam is endowed with high cell density (up to 1.9 × 106) and similar thermal conductivity as the neat PS foam, as well as high compression modulus. Therefore, the in situ polymerized ATP/PPy nanocomposite makes supercritical CO2 foaming desired candidate to replace the widely used fluorocarbons and chlorofluorocarbons as PS blowing agents.


2013 ◽  
Vol 716 ◽  
pp. 368-372
Author(s):  
Hui Xu ◽  
Jian Wei Xing

Polyaniline (PANI)/zinc oxide (ZnO) nanocomposites have been synthesized by in-situ polymerization of aniline monomer with ZnO nanomaterials. The PANI/ZnO nanocomposites were used as photocatalyst in the photodegradation of methylene blue dye (MB) molecules in aqueous solution. The results showed that PANI/ZnO nanocomposite greatly enhanced photocatalytic activities compared with pristine polyaniline might due to high photoexcited electronhole pairs charge separation. The photocatalytic activities of PANI/ZnO nanocomposites increased with increasing ZnO content, however, further increasing ZnO content over 50% induced the formation of more agglomerates, which could act as recombination centers of photoexcited electronhole pairs, leading to decreased photocatalytic activity. The kinetics of photodegradation of MB dye using PANI/ZnO(ZnO content 50 % ) nanocomposites photocatalyst was found to be of the first order.


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