scholarly journals Evaluation of Effect of Various Nanofillers on Technological Properties of NBR/NR Blend Vulcanized Using BIAT-CBS System

2013 ◽  
Vol 2013 ◽  
pp. 1-10
Author(s):  
Shaji P. Thomas ◽  
Saliney Thomas ◽  
C. V. Marykutty ◽  
E. J. Mathew

Owing to processing ease and resistance to oils and chemicals, NBR is widely used in many industries. But since neat NBR has only poor tensile properties, it is better to use suitable blends of NR and NBR after incorporating appropriate nanoingredients before vulcanization. It is well established that nanoparticles can be easily dispersed in a more uniform pattern in polymer matrix, thereby enhancing the technological properties of the elastomer vulcanizate. Since there are no systematic comparative studies on technological properties of NBR/NR blend containing different nanoingredients, efforts have been made in this study to investigate cure and technological properties like tensile properties, tear resistance, compression set, hardness, abrasion loss and swelling value of NBR/NR (80/20) blend vulcanizates containing stearic acid-coated nano-zinc oxide (ZOS), nano-BIAT, nano-silicate-coated CaCO3, PEO-coated calcium silicate, and surface-modified carbon nanotubes (CNT). XRD and electron microscopy have been used for morphological analysis. The nano ingredients were effective in enhancing the technological properties of the vulcanizates. Among the nanofillers, modified CNT was found to impart superior properties to NBR/NR blend due to more intercalation.

2014 ◽  
Vol 87 (1) ◽  
pp. 21-30 ◽  
Author(s):  
Zhongbiao Man ◽  
Li Deng ◽  
Miao Yang ◽  
Yuehui Chen ◽  
Zhengjie Jin

ABSTRACT In situ surface-modified nano–zinc oxide (ZnO) had been prepared by the sol-gel method. The microscopic structure of the ZnO particles was characterized by X-ray diffraction and transmission electron microscopy. Scanning electron microscopy with energy-dispersed X-ray spectroscopy was used to observe the dispersal of ZnO in conventional vulcanization of natural rubber (NR). Properties such as cure and tensile characteristics as well as heat-resistance oxygen aging properties were researched and compared. The vulcanized structure of vulcanizate was studied by the balance-swelling method and chemical-detecting process. Results demonstrated that the dispersal of in situ surface-modified nano-ZnO in NR vulcanizate was better than that of ordinary ZnO. Compared with the addition of 5 phr of ordinary ZnO in NR, the tensile strength and elongation of NR vulcanizate filled with 2 phr of in situ surface-modified nano-ZnO increased by 0.55% and 10.34%, respectively. Meanwhile, the retention of tensile strength and elongation of vulcanizate increased by 35.85% and 19.36%, respectively.


2015 ◽  
Vol 1107 ◽  
pp. 326-332
Author(s):  
Abdul Rahim Yacob ◽  
Kamaluddeen Suleiman Kabo

The use of metal oxides in heterogeneous base catalysis has gained a large interest due to their application in many chemical and industrial processes and is environmental friendly. Basic metal oxides are commonly used and their structures, morphology and performance can be modified by method of preparation and thermal activation. In this study, surface modified amphoteric zinc oxide was prepared via hydration-dehydration method and characterised by TGA and FTIR. The basic strength at various temperatures is characterised by FTIR and back titration analyses. The results shows that surface modified zinc oxide has the highest basic strength of 1.453mmolg-1at 400°C making it a relatively good and suitable compound for use in heterogeneous basic catalysis. This result is also supported by FTIR spectra which show possible relationship between the Lewis O2-and increasing basic strength.


Author(s):  
Koushik Guha Biswas ◽  
Lipika Das ◽  
Jayanta Kumar Basu

Abstract The study represents the development of nano zinc oxide catalyst coated with alumina by co-precipitation method for dehydrogenation reaction studies. The catalyst characterization was done by transmission electron microscopy (TEM), X-Ray diffraction (XRD), BET surface analyzer and scanning electron microscopy (SEM). The reaction chosen was dehydrogenation of 2-butanol to methyl ethyl ketone (MEK) with a variation of different operating parameters such as temperature, partial pressure, reactant flow rate. The conversion was investigated by varying catalyst amount and size. The role of reaction rate on various operating parameters like temperature, the partial pressure of reactant, catalyst to feed ratio has been explored. The rate of the reaction along with order and rate constant have been calculated. The activation energy was calculated from Arrhenius law to depict the nature and efficiency of the reaction chosen.


2018 ◽  
Vol 9 (1) ◽  
pp. 77-90 ◽  
Author(s):  
Saja Mohammed ◽  
◽  
Abdulkareem Alhumdany ◽  
Muhannad Al-Waily ◽  
◽  
...  

2020 ◽  
Vol 90 (21-22) ◽  
pp. 2492-2503
Author(s):  
MA Mousa ◽  
M Khairy

A liquid precipitation method was used to prepare zinc oxide nanoparticles in three diverse media: water, methanol, and ethylene glycol. The studied materials were examined by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and ultraviolet-visible spectroscopy. X-ray diffraction patterns showed a hexagonal Wurtzite structure of zinc oxide with a nanocrystalline size. Acquired powders showed different morphologies (rod, star, and spherical structures), which were affected by the nature of the solvent in the reaction. The different zinc oxide powders have varied optical band gaps. Scanning electron microscopy examinations confirmed the arrangement of nano-zinc oxide on the surfaces of the materials. The zinc oxide-covering procedure was carried out on cotton, polyester, and 50/50 wt% polyester/cotton blended fabrics using a simple dip and curing system. The cotton fabric treated with nanorod zinc oxide exhibited the highest ultraviolet protection factor with a value of 247.2. The antimicrobial properties of untreated and treated fabrics with nano-zinc oxide were measured against Gram-negative bacteria (Escherichia coli), Gram-positive bacteria (Staphylococcus aureus), and diploid fungus (Candida albicans). The results showed the antimicrobial action relies on the morphological structure and the particle size of zinc oxide and that it increases with a reduced particle size. The cotton fabric treated with 26 nm nonspherical zinc oxide particles showed the highest antimicrobial efficiency with values of 91.4%, 86.8%, and 84.7% for Staphylococcus aureus, Escherichia coli, and Candida albicans, respectively. The mechanical properties of treated fabrics were studied. The results confirm that nano-zinc oxide is highly useful for improving the performance of defense textile products because of its biocompatibility, environmental friendliness, and nontoxicity.


2014 ◽  
Vol 910 ◽  
pp. 101-104 ◽  
Author(s):  
Jin Yu Qi ◽  
Li Xin Wu ◽  
Dong Xian Zhuo

nanozinc oxide (n-ZnO) was synthesized by sol-gel method. The surface of n-ZnO was modified by a silane coupling agent. The modified n-ZnO was then used as rubber vulcanizing activator and nanofiller for BR/SBR blends. The size and morphology of n-ZnO were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of modified n-ZnO on cure characteristics, mechanical properties and thermal conductivity of BR/SBR blends were tested and analyzed. The use of modified n-ZnO resulted in less optimum cure time (t90), higher mechanical properties (anti-abrasion, tear strength, tensile strength, tensile modulus) and thermal conductivity at lower content compared to the conventional micro ZnO(c-ZnO).


Author(s):  
P. S. Sklad

Over the past several years, it has become increasingly evident that materials for proposed advanced energy systems will be required to operate at high temperatures and in aggressive environments. These constraints make structural ceramics attractive materials for these systems. However it is well known that the condition of the specimen surface of ceramic materials is often critical in controlling properties such as fracture toughness, oxidation resistance, and wear resistance. Ion implantation techniques offer the potential of overcoming some of the surface related limitations.While the effects of implantation on surface sensitive properties may be measured indpendently, it is important to understand the microstructural evolution leading to these changes. Analytical electron microscopy provides a useful tool for characterizing the microstructures produced in terms of solute concentration profiles, second phase formation, lattice damage, crystallinity of the implanted layer, and annealing behavior. Such analyses allow correlations to be made with theoretical models, property measurements, and results of complimentary techniques.


Alloy Digest ◽  
2015 ◽  
Vol 64 (9) ◽  

Abstract Wieland-SW1 is a lead-free special brass made in extruded and drawn products. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fatigue. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: Cu-841. Producer or source: Wieland Metals Inc. and Wieland-Werke AG.


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2174
Author(s):  
Diana Gregor-Svetec ◽  
Mirjam Leskovšek ◽  
Blaž Leskovar ◽  
Urška Stanković Elesini ◽  
Urška Vrabič-Brodnjak

Polylactic acid (PLA) is one of the most suitable materials for 3D printing. Blending with nanoparticles improves some of its properties, broadening its application possibilities. The article presents a study of composite PLA matrix filaments with added unmodified and lignin/polymerised lignin surface-modified nanofibrillated cellulose (NFC). The influence of untreated and surface-modified NFC on morphological, mechanical, technological, infrared spectroscopic, and dynamic mechanical properties was evaluated for different groups of samples. As determined by the stereo and scanning electron microscopy, the unmodified and surface-modified NFCs with lignin and polymerised lignin were present in the form of plate-shaped agglomerates. The addition of NFC slightly reduced the filaments’ tensile strength, stretchability, and ability to absorb energy, while in contrast, the initial modulus slightly improved. By adding NFC to the PLA matrix, the bending storage modulus (E’) decreased slightly at lower temperatures, especially in the PLA samples with 3 wt% and 5 wt% NFC. When NFC was modified with lignin and polymerised lignin, an increase in E’ was noticed, especially in the glassy state.


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