scholarly journals Sustainable Functionalization of PAN to Improve Tinctorial Capacity

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3665
Author(s):  
Vasilica Popescu ◽  
Ingrid Ioana Buciscanu ◽  
Melinda Pruneanu ◽  
Stelian Sergiu Maier ◽  
Angela Danila ◽  
...  

This study may open a new way to obtain the coloration of a polymer during functionalization. Two polyacrylonitrile (PAN) polymers in the form of textile fibers (Melana and Dralon L) were subjected to functionalization treatments in order to improve the dyeing capacity. The functionalizations determined by an organo-hypervalent iodine reagent developed in situ led to fiber coloration without using dyes. KIO3 was formed in situ from the interaction of aqueous solutions of 3–9% KOH with 3–9% I2, at 120 °C. The yellow-orange coloration appeared as a result of the transformations in the chemical structure of each functionalized polymer, with the formation of iodinehydrin groups. The degree of functionalization directly influenced the obtained color. The results of the Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX), Map and Temogravimetric Analysis (TG) plus Differential Thermal (DTA) analyses indicated the presence of new functional groups, such as iodine-oxime. The X-ray diffraction (XRD) analysis confirmed the change of the crystalline/amorphous ratio in favor of the former. The new groups introduced by functionalization make it possible to dye with classes of dyes specific to these groups, but not specific to PAN fibers, thus improving their dyeing capacity.

2013 ◽  
Vol 821-822 ◽  
pp. 23-27
Author(s):  
Xiang Li ◽  
Chun Yi Liu ◽  
Ai Wen Qin ◽  
Xin Zhen Zhao ◽  
Chun Ju He

Plasticized polyacrylonitrile(PAN) fibers have been chemically impregnated with aqueous solution of KMnO4under varying conditions of temperature and time. The effect of modification conditions on the chemical structure and the mechanical properties of precursor fibers are characterized by wide-angle X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscope. The experimental results show that KMnO4can be used not only as catalyst for cyclization reaction, but also as plasticizer. The chemical modification between KMnO4and PAN can not occur below70°C, the most suitable condition for modification is performed at 80°C for 5 min.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


2014 ◽  
Vol 881-883 ◽  
pp. 1049-1052 ◽  
Author(s):  
Nai Peng ◽  
Cheng Ji Deng ◽  
Hong Xi Zhu

In this paper, the effects of briquetting pressure on the performance of in-situ formed Sialon in Al2O3-C refractory bricks are investigated. The phase compositions and microstructure of the Al2O3-C refractory were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM).The results show the briquetting pressure hardly has effect on the phase of the sintered specimens, two new phases of Sialon with a Z value of 2 and SiC formed. The micrographs of Sialon crystals have the shape of both column and tabular column, but with a cone tip in the specimens sintered at 200MPa and 300MPa and smooth tip in specimens sintered at 400MPa and 500MPa.


Chemija ◽  
2019 ◽  
Vol 30 (2) ◽  
Author(s):  
Andrius Laurikėnas ◽  
Fatma Yalçin ◽  
Robertas Žilinskas ◽  
Ayse Uztetik Morkan ◽  
Albinas Žilinskas ◽  
...  

The solvothermal synthesis between Me(NO3)x ∙ yH2O (Mex+ = Fe3+, Ni2+, Mn2+, Co2+, Cu2+) and respectively 4-nitrosalycilic (4NSA) and 5-sulfosalicylic (5SSA) acids produced hybrid organic-inorganic compounds composed of Mex+ ions and organic fragments which include three different functional groups, carboxylic, hydroxyl and sulfonic, each coordinated to the Mex+ ions. The phase and chemical composition, microstructure and properties of Me2(H2O)4(5SSA)3·DMF and Me2(H2O)4(4NSA)2·DMF (DMF – dimethylformamide) hybrid compounds were evaluated and discussed. The synthesised materials were characterised by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) spectroscopy. The catalytic properties of the obtained compounds were also investigated.


2010 ◽  
Vol 663-665 ◽  
pp. 542-545 ◽  
Author(s):  
Bing Jie Zhu ◽  
Xin Wei Wang ◽  
Mei Fang Zhu ◽  
Qing Hong Zhang ◽  
Yao Gang Li ◽  
...  

The PANI/ITO conducting nanocomposites have been synthesized by in-situ polymerization. The obtained nanocomposites were characterized by X-ray diffraction pattern, scanning electron microscopy and Fourier transform infrared. Electrical conductivity measurements on the samples pressed into pellets showed that the maximum conductivity attained 2.0 ± 0.05 S/cm for PANI/ITO nanocomposites, at ITO doping concentration of 10 wt%. The results of the present work may provide a simple, rapid and efficient approach for preparing PANI/ITO nanocomposites.


2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Hassan Ilyas ◽  
Ishtiaq A. Qazi ◽  
Wasim Asgar ◽  
M. Ali Awan ◽  
Zahir-ud-din Khan

Pure and Ag-TiO2nanoparticles were synthesized, with the metallic doping being done using the Liquid Impregnation (LI) method. The resulting nanoparticles were characterized by analytical methods such as scanning electron micrographs (SEMs), Energy Dispersive Spectroscopy (EDS), and X-ray diffraction (XRD). XRD analysis indicated that the crystallite size ofTiO2was 27 nm to 42 nm while the crystallite size of Ag-TiO2was 11.27 nm to 42.52 nm. The photocatalytic activity of pureTiO2and silver dopedTiO2was tested by photocatalytic degradation ofp-nitrophenol as a model compound. Ag-TiO2nanoparticles exhibited better results (98% degradation) as compared to pureTiO2nanoparticles (83% degradation) in 1 hour for the degradation ofp-nitrophenol. Ag-TiO2was further used for the photocatalytic degradation of 2,4-dichlorphenol (99% degradation), 2,5-dichlorophenol (98% degradation), and 2,4,6-trichlorophenol (96% degradation) in 1 hour. The degree of mineralization was tested by TOC experiment indicating that 2,4-DCP was completely mineralized, while 2,5-DCP was mineralized upto 95 percent and 2,4,6-TCP upto 86 percent within a period of 2 hours.


Cerâmica ◽  
2016 ◽  
Vol 62 (364) ◽  
pp. 386-391 ◽  
Author(s):  
J. R. M. Ferreira ◽  
L. H. L. Louro ◽  
A. M. Costa ◽  
J. B. de Campos ◽  
M. H. Prado da Silva

Abstract In the present study, hydroxyapatite and Zn-substituted hydroxyapatite powders were synthesized using ostrich eggshell as a calcium source. The samples were analyzed by scanning electron microscopy with field emission gun, and X-ray diffraction (XRD) to identify the present phases, and X-ray fluorescence spectroscopy for quantitative chemical analysis of the synthesized and heat treated powders. The Fourier transform infrared spectroscopy technique was used before and after heat treatments at 700, 900 and 1100 °C in order to identify the functional groups present, as an additional technique to the XRD analysis. The results presented in this study represent a promising method for synthesis of hydroxyapatite and hydroxyapatite partially substituted with zinc, since the results showed no undesirable phases or impurities in the produced powders. It was observed that Zn-substituted hydroxyapatite showed higher thermal stability, when compared to pure hydroxyapatite.


2013 ◽  
Vol 457-458 ◽  
pp. 244-247
Author(s):  
Min Li ◽  
Li Guang Xiao ◽  
Hong Kai Zhao

Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The morphology of MMT/MgCl2/TiCl4 catalyst and PE/MMT nanocomposites was investigated by scanning electron microscopy (SEM). It can be seen that MMT/MgCl2/TiCl4 catalyst remained the original MMT sheet structures and many holes were found in MMT and the morphology of PE/MMT nanocomposites is part of the sheet in the form of existence, as most of the petal structure. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were carried out to characterize all the samples. XRD results reveal that the original basal reflection peak of PEI1 and PEI2 disappears completely and that of PEI3 become very weak. MMT/MgCl2/TiCl4 catalyst was finely dispersed in the PE matrix. Instead of being individually dispersed, most layers were found in thin stacks comprising several swollen layers.


2019 ◽  
Vol 969 ◽  
pp. 169-174
Author(s):  
R. Sivanand ◽  
S. Chellammal ◽  
S. Manivannan

In this paper, the effect of size variation of cadmium sulphide nanocrystallites which have been prepared by precipitation method is analyzed. These prepared samples were studied using X-ray diffraction (XRD), Scanning electron microscopy (SEM), and Energy dispersive analysis of spectroscopy (EDAX) techniques. SEM analysis represents the morphological nature of prepared samples and EDAX indicates the confirmation of elements present in the sample. XRD analysis determines the size of the samples and identifies the structure using miller indices (h k l values) of the nanocrystallies matches with JCPDS. From the XRD analysis, the size variation which depends on dopant, capping agent are discussed and corresponding results are reported in this paper.


2012 ◽  
Vol 616-618 ◽  
pp. 1732-1735 ◽  
Author(s):  
Xi Hai Shen ◽  
Yu Gang Zheng ◽  
Liang Chang ◽  
Jin Jia Guo ◽  
Song Bin Ye ◽  
...  

Aiming at the glass-to-metal seals serving in the Solar Thermal Power (STP), glass-to-metal vacuum brazed joints were studied. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were performed to examine the microstructure and element contents of interface seam on the glass-to-metal vacuum brazed joints. Also, the compositional concentration of the interface seam was measured by using energy dispersive spectroscopy (EDS).


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