scholarly journals The effect of hydrogenation of epoxy resin on the dispersion of organo-clay in the epoxy resin matrix

2020 ◽  
Author(s):  
Xiyang Kang ◽  
Qing Zhu ◽  
Xiaoliang Wang ◽  
Dongshan Zhou ◽  
zhijun Chen

Abstract The hydrogenated diglycidylether of Bisphenol A epoxy resin (HDGEBA)was successfully employed to prepare nanocomposites with a more homogeneous distribution of clay, compared to that of bisphenol A epoxy resin (DGEBA)/clay system. Nanocomposites, with amounts up to 7.5 wt% of Organo-clay, were synthetized by means of “slurry-compounding” method and followed by a curing process with cis-1,2-Cyclohexanedicarboxylic anhydride and Glutaric Anhydride as the curing agent. A combination of X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the dispersion behavior of organo-clay in epoxy/clay nanocomposites. It was found that, in HDGEBA/clay nanocomposites, organo-clay was uniformly dispersed and even partly exfoliated, whereas, in DGEBA/clay system, large particle aggregates were seen when examined by TEM under lower magnification. Accordingly, the rheology and compatibility experiments were carried out to investigate the interactions within each system. It turned out that, after hydrogenation, HDGEBA was endowed with stronger interactions with organo-clay, thus resulting in the enhanced dispersion behavior, which may generate more chances to be mechanically reinforced by adding inorganic clays.

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1397 ◽  
Author(s):  
Elaine dos Santos ◽  
Marcus Fook ◽  
Oscar Malta ◽  
Suédina de Lima Silva ◽  
Itamara Leite

Purified clay was modified with different amounts of alkyl ammonium and phosphonium salts and used as filler in the preparation of PET nanocomposites via melt intercalation. The effect of this type of filler on morphology and thermal and mechanical properties of PET nanocomposites was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile properties, and transmission electron microscopy (TEM). The results showed that the mixture of alkyl ammonium and phosphonium salts favored the production of PET nanocomposites with intercalated and partially exfoliated morphologies with slight improvement in thermal stability. In addition, the incorporation of these organoclays tended to inhibit PET crystallization behavior, which is profitable in the production of transparent bottles.


2005 ◽  
Vol 13 (5) ◽  
pp. 525-527
Author(s):  
Cheng Yiyun ◽  
Cui Ronghui ◽  
He Pingsheng

This study presents a new method of preparing Mg(OH)2/epoxy resin nanocomposites. An epoxy resin micro-emulsion is taken as a micro-reactor for the formation of Mg(OH)2 nano-crystals. After the reaction, the collected epoxy proved to be a composite with embedded nano-Mg(OH)2. Transmission electron microscopy (TEM) indicated that the Mg(OH)2 nano-crystals were dispersed uniformly in cured epoxy resin matrix.


Author(s):  
Yang Zhao ◽  
Han-Xiong Huang

The polypropylene (PP)/clay nanocomposites were prepared using a twin screw extruder with the aid of the supercritical carbon dioxide (Sc-CO2). The dynamic rheological properties were measured using a rheometer in the oscillatory mode. X-ray diffraction and transmission electron microscopy were used to characterize the microstructure of extruded nanocomposites. Results showed that an optimized CO2 concentration existed. When the CO2 concentration increased up to the optimized level, the nanocomposites tended to be more viscous, especially at low frequency. Whereas further increasing the CO2 concentration resulted in the decrease in the complex viscosity and dynamic moduli. The presence of Sc-CO2 with the concentration not higher than the optimized level was helpful to promote the degree of dispersion of the nano-clay in PP matrix, and overloaded CO2 would have negative effect on the clay dispersion.


2020 ◽  
Vol 98 (12) ◽  
pp. 771-778
Author(s):  
Xin Chang ◽  
Xiangyang Xu ◽  
Zhifeng Gao ◽  
Yingrui Tao ◽  
Yixuan Yin ◽  
...  

A nanocomposite, reduced graphene oxide (RGO) modified ZnCo2O4 (ZnCo2O4–RGO) was synthesized via one-step solvothermal method for activating persulfate (PS) to degrade bisphenol A (BPA). The morphology and structure of the nanocomposite were identified by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. RGO provides nucleation sites for ZnCo2O4 to grow and inhibits the agglomeration of the nanoparticles. The influence of different reaction conditions on the oxidation of BPA catalyzed by ZnCo2O4–RGO was investigated, including the content of RGO, the dosage of catalyst, the concentration of humic acid (HA), anions in the environment, the reaction temperature, and pH. BPA can be totally degraded within 20 min under optimized reaction conditions. The presence of HA, Cl−, and NO3− only has a slight effect on the oxidation of BPA, whereas the presence of either H2PO4− or HCO3− can greatly inhibit the reaction. ZnCo2O4–RGO shows good cycling stability and practical application potential. A reaction mechanism of the degradation of BPA was also explored.


2007 ◽  
Vol 124-126 ◽  
pp. 1083-1086
Author(s):  
Jun Hee Sung ◽  
Hyoung Jin Choi

Nanocomposites of conducting polymers of polyaniline (PANI), poly(oethoxyaniline) (PEOA) and polypyrrole (PPy) with clay prepared via either in-situ emulsion polymerization or solvent intercalation were investigated especially for electrorheological fluid (ER) application. Internal structures of these nanocomposites were examined via wide angle X-ray diffraction (WAXD), and transmission electron microscope (TEM). The intercalated nanostructures analyzed via WAXD and TEM were correlated with the electrical property change originated from the nanoscale interaction between clay and conducting polymer. Moreover, their ER behaviors were measured via rotational rheometer with external electric field controller.


Nano Hybrids ◽  
2016 ◽  
Vol 10 ◽  
pp. 20-27 ◽  
Author(s):  
S. Nallusamy ◽  
N. Manikanda Prabu

Polymer composite with reinforced fiber is a remarkable development in the field of engineering materials. The applications of composite materials have significantly increased in Defense, Aeronautical and Automobiles because of its specific modulus and high strength characteristics. In composite material development, nano particles reinforcement and nano fiber reinforcement are the most recent methods developed. In this research electrospun carbon nanofiber reinforced mat with polymer epoxy resin composites was prepared. X-ray diffraction, scanning electron microscope and ultrasonic scanning were used to study the morphology and the defect on the specimens for analyzing the structural conditions of the samples for determining the mechanical properties. The result clearly indicates that the Carbon Nanofiber (CNF)/ Polyvinyl Alcohol (PVA) mat improves the flexural strength of the epoxy resin and that 0.015% CNF in PVA gives a better mechanical strength.


e-Polymers ◽  
2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Mohammad Galehassadi ◽  
Fatemeh Hosseinzadeh ◽  
Mehrdad Mahkam

Abstract Nanocomposites of polystyrene (PS) was prepared with new styrenic ionic liquid, N-(4-vinyl benzyl)-(N,N-dimethylamino) pyridinium chloride[VBMAP], surfactants used as organic modifications for the clays. Sodium montmorillonite (Na-MMT) was successfully modified by [VBMAP] to become OMMT through cation exchange technique which is shown by the increase of basalspacing of clay by XRD. The composite material based on polystyrene and organo-modified montmorillonite (OMMT) was prepared by insitu polymerization and characterized. The morphology of the polymer/clay hybrids was evaluated by X-ray diffraction (XRD) ,transmission electron microscopy (TEM) and scanning electron microscopy (SEM), showing good overall dispersion of the clay. The thermal stability of the polymer/clay nanocomposites were enhanced, as evaluated by thermogravimetric analysis.


2007 ◽  
Vol 334-335 ◽  
pp. 877-880 ◽  
Author(s):  
Jae Hun Shim ◽  
Jae Hun Choi ◽  
Jung Hiuk Joo ◽  
Jin San Yoon

A new method was attempted to improve the interaction between nylon 6 with a commercially available organoclay, Cloisite®25A (C25A) through modification of C25A with 3-aminopropyltriethoxy silane, 3-(trimethoxysilyl)propyl methacrylate, 3-(glycidoxypropyl) trimethoxysilane and 3-isocyanate propyltriethoxy silane. C25A and C25A modified with the silane compounds(TFC) were melt mixed with nylon 6. X-Ray diffraction and transmission electron microscopy images revealed that all the TFC layers were fully exfoliated in nylon 6 matrix irrespectively of the type of the silane compounds used for the modification. Tensile properties of nylon 6 were most significantly improved when 3-(glycidoxypropyl)trimethoxysilane modified C25A was incorporated. The chemical reaction between the epoxy groups and the end groups of nylon 6 raised the interfacial interaction and thus was responsible for the enhanced tensile properties.


2010 ◽  
Vol 123-125 ◽  
pp. 247-250
Author(s):  
Yu Qing Zhang ◽  
Yu Xin He ◽  
Li Zhang ◽  
Jun Xian Li

A new type of EVA-g-PU/OMMT nanocomposites was synthesized through the method of chemical modification and melt intercalation. FTIR testing showed that the PU prepolymer was grafted on EVA main chains successfully. The structures of EVA-g-PU/OMMT nanocomposites were characterized by X-ray diffraction (XRD) and by high-resolution transmission electron microscopy (HRTEM). The enhanced storage modulus of EVA-g-PU/OMMT nanocomposites was characterized by dynamic mechanical analysis (DMA). The thermal stabilities of EVA/clay nanocomposites were also studied by thermal gravimetric analysis (TGA). Mechanical testing showed that the tensile strength and tear strength of EVA-g-PU/OMMT nanocomposites were far superior to pure EVA.


2011 ◽  
Vol 418-420 ◽  
pp. 670-673 ◽  
Author(s):  
Kun Yan Wang ◽  
Shi Yang Zhou ◽  
Zhen Jiang ◽  
Xiao Qing Zhu

A new ultrasonication dispersion – microwave cure (UD-MC) method for preparing highly exfoliated layered epoxy/clay nanocomposites was developed. The process was divided into two consecutive stages. In the first stage, the epoxy and organoclay were mixed by high stirring and ultrasonication in the presence of acetone. In the second stage, the mixture of epoxy and organoclay was cured with microwave of 400W and postcured at 135°C. The microstructure of the nanocomposites was characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results indicated that the basal spacing of the organoclay particles in the epoxy/clay mixture was significantly enlarged, up to around 75Å afther the ultrasonic treatment. The layered clay was highly exfoliated under the microwave energy; and the basal spacing of nanolayers was more than 90Å.


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