scholarly journals In-situ Polymerization of exfoliated structure PA6/organo-clay nanocomposites

2020 ◽  
Vol 59 (1) ◽  
pp. 434-440
Author(s):  
Yiming Sun ◽  
Jie Mei ◽  
Huan Hu ◽  
Jiru Ying ◽  
Weiyi Zhou ◽  
...  

AbstractMontmorillonite (MMT) was modified with cetyl trimethyl ammonium bromide (CTAB) to obtain organomontmorillonite (OMMT) by stirring and pulsed ultrasonic mixing. Polyamide 6 (PA6)/OMMT nanocomposites were then prepared via in-situ polymerization.The resulting OMMT and PA6/OMMT nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results suggested that the OMMT interlayer distance was greatly increased to 3.13 nm due to CTAB being inter-calated into the MMT galleries. The OMMT interlayer distance was further enlarged to 10-20 nm during the polymerization process. The OMMT layers were exfoliated into nanoscale layers and uniformly dispersed in the molten ∈-caprolactam and PA6 matrix, and exfoliated structure nanocomposites were formed.

2010 ◽  
Vol 148-149 ◽  
pp. 1547-1550 ◽  
Author(s):  
Hua Lan Wang ◽  
Qing Li Hao ◽  
Xi Feng Xia ◽  
Zhi Jia Wang ◽  
Jiao Tian ◽  
...  

A graphene oxide/polyaniline composite was synthesized by an in situ polymerization process. This product was simply prepared in an ethylene glycol medium, using ammonium persulfate as oxidant in ice bath. The composite was characterized by field emission scanning electron microscopy, transmission electron microscopy, X-Ray photoelectron spectroscopy, Raman spectroscopy and electrochemical test. The composite material showed a good electrochemical performance.


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 2019 ◽  
pp. 1-17
Author(s):  
M. A. Domínguez-Crespo ◽  
A. B. López-Oyama ◽  
A. M. Torres-Huerta ◽  
A. R. Hernández-Basilio ◽  
D. Palma-Ramírez ◽  
...  

In this work, hybrid composites were prepared using polyaniline (PANI) and electrochemically reduced graphene oxide (ERGO) by in situ polymerization. ERGO powders were obtained by a two-way route, Hummer’s method, and one-step potential (−2 V) followed by annealing process at 400°C (TERGO powders): different quantities of TERGO fine particles (10, 20, and 30 wt%) were added to the in situ PANI polymerization in order to produce the hybrid composites. The morphology and structure of the PANI/TERGO compounds were characterized by Raman spectroscopy, ultraviolet-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Thermal treatment of ERGO powders pointed out high-defect surfaces with a wrinkle-type morphology (ID/IG ratio~0.90). The emeraldine phase of PANI was obtained with a maximum value of 61%, which decreases with the amount of TERGO powders. It is also seen that composites displayed a combined morphology between PANI matrix and TERGO powders, confirming a physical interaction between both morphologies. The amount of TERGO particles into the polymeric matrix also modifies the sample microstructure from a semispherical shape to extend sheets, where PANI is sandwiched between TERGO layers. Electrical conductivity of composites slightly increases independent of the TERGO amount (30 S/m and 39 S/m) due to the rough TERGO surface that conditioned the homogeneous nucleation of a large amount of polymer (PANI) reducing the area to move the electrical charge.


RSC Advances ◽  
2014 ◽  
Vol 4 (93) ◽  
pp. 51244-51255 ◽  
Author(s):  
Santosh K. Gupta ◽  
P. S. Ghosh ◽  
A. Arya ◽  
V. Natarajan

Nanorods of ThO2 were synthesized in a reverse micelle technique using cetyl trimethyl ammonium bromide as a surfactant and characterized by X-ray diffraction and transmission electron microscopy.


MRS Advances ◽  
2016 ◽  
Vol 1 (42) ◽  
pp. 2893-2899 ◽  
Author(s):  
R.W. Harrison ◽  
H. Amari ◽  
G. Greaves ◽  
J.A. Hinks ◽  
S.E. Donnelly

AbstractIn-situ ion irradiation and transmission electron microscopy has been used to examine the effects of the He appm to DPA ratio, temperature and dose on the damage structure of tungsten (W). Irradiations were performed with 15 or 60 keV He+ ions, achieving He-appm/displacements per atom (DPA) ratios of ∼40,000 and ∼2000, respectively, at temperatures between 500 and 1000°C to a dose of ∼3 DPA. A high number of small dislocation loops with sizes around 5–20 nm and a He bubble lattice were observed for both He-appm/DPA ratios at 500°C with a bubble size ∼1.5 nm. Using the g.b=0 criterion the loops were characterised as b = ±1/2<111> type. At 750°C bubbles do not form an ordered array and are larger in size compared to the irradiations at 500°C, with a diameter of ∼3 nm. Fewer dislocation loops were observed at this temperature and were also characterised to be b = ±1/2<111> type. At 1000°C, no dislocation loops were observed and bubbles grew as a function of fluence attributed to vacancy mobility being higher and vacancy clusters becoming mobile.


Parasitology ◽  
1993 ◽  
Vol 107 (5) ◽  
pp. 545-552 ◽  
Author(s):  
D. L. Lee ◽  
K. A. Wright ◽  
R. R. Shivers

SUMMARYThe surface of the cuticle of adult Nippostrongylus brasiliensis has been studied by means of the freeze-fracture technique and by transmission electron microscopy. Some of the surface coat appears to have been shed from the surface of the cuticle of adults fixed in situ in the intestine of its host and from the surface of individuals removed from the intestine and freeze-fractured. Freeze-fracturing the cuticle of individuals removed from the host has shown that this surface coat varies in thickness from 30 to 90 nm. The epicuticle is about 20 nm thick and cleaves readily to expose E- and P-faces. The P-face of the epicuticle possesses a small number of particles, similar to intra-membranous particles, whilst the E-face possesses a few, widely scattered depressions. Despite the presence of these particles the epicuticle is not considered to be a true membrane. Freeze-fracturing the remainder of the cuticle has confirmed its structure as described by conventional transmission electron microscopy. Clusters of particles on the P-face of the outer epidermal (hypodermal) membrane and corresponding depressions on the E-face of the membrane are thought to be associated with points of attachment of the cuticle to the epidermis (hypodermis). No differences in appearance of the cuticle and its surface layers were observed in individuals taken from 7-, 10-, 13- and 15-day infections.


Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2787
Author(s):  
Cheng-Ho Chen ◽  
Ying-Chen Lin ◽  
Fu-Su Yen

Polyaniline doped with dodecylbenzenesulfonic acid/χ-aluminum oxide (PANDB/χ-Al2O3) conducting core-shell nanocomposites was synthesized via an in situ polymerization method in this study. PANDB was synthesized in the presence of dodecylbenzenesulfonic acid (DBSA), which functioned as a dopant and surfactant. The electrical conductivity of the conducting PANDB/χ-Al2O3 core-shell nanocomposite was approximately 1.7 × 10−1 S/cm when the aniline/χ-Al2O3 (AN/χ-Al2O3) weight ratio was 1.5. The transmission electron microscopy (TEM) results indicated that the χ-Al2O3 nanoflakes were thoroughly coated by PANDB to form the core-shell (χ-Al2O3-PANDB) structure. The TEM and field-emission scanning electron microscopy (FE-SEM) images of the conducting PANDB/χ-Al2O3 core-shell nanocomposites also indicated that the thickness of the PANDB layer (shell) could be increased as the weight ratio of AN/χ-Al2O3 was increased. In this study, the optimum weight ratio of AN/χ-Al2O3 was identified as 1.5. The conducting PANDB/χ-Al2O3 core-shell nanocomposite was then blended with water-based polyurethane (WPU) to form a conducting WPU/PANDB/χ-Al2O3 blend film. The resulting blend film has promising antistatic and electrostatic discharge (ESD) properties.


2018 ◽  
Vol 8 ◽  
pp. 184798041878197 ◽  
Author(s):  
Wenzheng Wu ◽  
Longjian Zhang ◽  
Xiaojie Zhai ◽  
Ce Liang ◽  
Kaifeng Yu

Combining the advantages of the sol–gel method and solvothermal method, the single anatase phase of nano-titanium dioxide (TiO2) with high crystallinity had been prepared by means of the sol–solvent thermal improved process, in which butyl titanate was used as titanium source; anhydrous ethanol as solvent; concentrated nitric acid as inhibitor; and cationic surfactant cetyl trimethyl ammonium bromide (CTAB), anionic surfactant sodium dodecyl benzene sulfonate (SDBS), and nonionic surfactant polyethylene glycol (PEG) as dispersants. The analysis results of Brunauer–Emmett–Teller, scanning electron microscopy, and transmission electron microscopy characterizations indicated that CTAB-modified TiO2 with the optimum ratio had the most apparent dispersibility and the highest specific surface area compared with unmodified TiO2, SDBS-modified TiO2, and PEG-modified TiO2. At the same time, the photocatalytic degradation rate of methyl orange could be improved to 99.16%. It indicated that the modification effect of CTAB was significantly better than those of SDBS and PEG, which made the nanoparticles uniformly dispersed, resulting in higher photocatalytic activity.


2021 ◽  
Author(s):  
Parthiban E ◽  
Sudarsan S

Abstract The silver nanoparticles (AgNPs) have been embedded within the itaconic acid (IA), polyaniline (PANi), and copper oxide (CuO) to form Ag@PANi-IA-CuO polymeric nanocomposites. In-situ polymerization of itaconic acid has been carried out in the presence of aniline monomers using anhydrous iron trichloride as an oxidising agent. The piper betel leaf extract was used to a reduction of AgNO3. The anchoring of AgNPs onto nanocomposite has been characterized using different techniques such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) X-ray diffraction (XRD), and energy-dispersive X-ray (EDX). Biological, magnetic, and thermal properties of nanocomposites have also been studied in antimicrobial, vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). Hence, these types of silver nanoparticles anchored polyaniline-itaconic acid-CuO nanocomposite has shown an attractive application in the field of biomedical and wastewater treatment.


2010 ◽  
Vol 150-151 ◽  
pp. 386-390
Author(s):  
Yuan Xun Li ◽  
Ying Li Liu ◽  
Huai Wu Zhang ◽  
Wei Wei Ling

The rod-shaped polyaniline (PANI)-barium ferrite nanocomposites were synthesized by in situ polymerization of aniline in the presence of BaFe12O19 nanoparticles with diameters of 60-80 nm. The composites obtained were characterized by infrared spectra (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The thermal stability and the composition of the composites were investigated by TG-DTG analysis. The results indicate that the thermal stability of the composites is higher than that of the pure PANI which can be attributed to the interactions existed between PANI chains and ferrite particles.


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