scholarly journals EPOXY ANTIFRICTION COATINGS FILLED WITH THE RICE HUSKS ASH TREATED WITH SURFACTANTS

2021 ◽  
pp. 28-36
Author(s):  
A. R. Valeeva ◽  
◽  
E. M. Gotlib ◽  
E. S. Yamaleeva ◽  
◽  
...  
Keyword(s):  
Wear Resistance ◽  
Rice Husk ◽  
Quaternary Ammonium ◽  
Bending Strength ◽  
Rice Husk Ash ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
High Wear Resistance ◽  
Antifriction Coatings ◽  
Antifriction Properties

The use of epoxy antifriction coatings can significantly reduce thermal stress in the friction zone and expand the coating working temperature interval while keeping high wear resistance. The paper considers the effect of non-activated and activated by surfactants silicate filler – rice husk ash on the physicochemical and mechanical properties of epoxy materials applied as antifriction coatings. All studied samples of rice husk ash, both initial and activated with surfactants, have an alkaline surface nature. The study identified that all cationic quaternary ammonium salts (QAS) reduce the pH of rice husk ash. At the same time, nonionic OXIPAV increases this indicator. Activation of the rice husk ash surface, both by the quaternary ammonium salts and aminosilanes, significantly reduces the porosity of this silicate. In this case, the average pore diameter does not change significantly, and their specific surface area decreases significantly, to a lesser extent, when activated by nonionic quaternary ammonium salts. The application of quaternary ammonium salts and aminosilanes in the amount of 33 % for activation of the surface of the investigated silicate filler reduces its modifying effect in epoxy compositions, regardless of the chemical structure of the surfactants used, which is not a typical effect. Therefore, the authors assumed that the suboptimal concentration of quaternary ammonium salts and aminosilanes was used. The study identified that the optimal concentration of 50 % alcohol solution of KATAPAV is 14.7–21 %. In this range of the QAS content, there is a significant increase in hardness (about 40 %), a slight decrease in wear (about 10 %), and a significant decrease in the coefficient of static friction (up to 2 times). At the same time, the authors observed an increase in adhesion to metal up to 3 times and bending strength up to 25 %. Thus, rice husk ash activated with an optimal amount of quaternary ammonium salts is an effective modifier of epoxy coatings, which improves their antifriction properties and increases wear resistance, hardness, strength, and adhesion characteristics.

scholarly journals Epoxy antifriction wollastonite-filled materials

Vestnik MGSU ◽  
2019 ◽  
pp. 311-321
Author(s):  
Elena M. Gotlib ◽  
Аlmira R. Khasanova ◽  
Engel R. Galimov ◽  
Аlla G. Sokolova
Keyword(s):  
Wear Resistance ◽  
Friction Coefficient ◽  
Adhesion Strength ◽  
Quaternary Ammonium ◽  
Epoxy Compound ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Antifriction Properties ◽  
The Impact ◽  
Compound Materials

Introduction. Domestic mineral natural-origin filler ‘wollastonite’, also known as calcium methyl silicate, is widely used as a base for wear-resisting epoxy antifriction materials. Due to anisodiametric shape of its particles, wollastonite functions as a micro reinforcement fibre enhancing adhesion strength and wear resistance of epoxy compositions, improving their antifriction properties, especially when organomodifying by quaternary ammonium salts. In this regard, the investigation of the impact of chemical composition of such surfactants as quaternary ammonium salts on the properties of epoxy compound materials presents utmost interest for researchers developing low-friction materials. Materials and methods. Epoxy diane resin ED-20 was hardened with aminoalkylphenol AF-2. Content of epoxy hardener was determined by equimolar ratio of epoxy groups to amine groups. Domestic wollastonite of the grade Miwoll 10-97 was used as filler, particle length to the diameter correlated as 15:1. The wollastonite surface was activated with surfactants belonging to domestically produced quaternary ammonium salts. Wear resistance of specimens was tested by means of the vertical optical caliper IZV-1. Friction coefficient was estimated with the assistance of the computer-automated frictional machine CSM Instruments Tribometer. Adhesion strength of glue joint was determined as per GOST 28840-90 standard. Two bars of sheet aluminium were used as glued surfaces as per GOST 14759-69 standard. Results. Reduction of wear of epoxy coatings when modified with micro reinforcing wollastonite can be explained by the increase of cross-linking degree of the polymer. The length of alkyl radical of quaternary ammonium salts used for wollastonite surface activation affects the intervals between the epoxy links. As the quaternary ammonium salt chain length is growing, wear of epoxy materials is reducing. Introduction of the wollastonite containing metallic oxides in the epoxy composites increases wear resistance and adhesion strength and reduces coating friction coefficients. Conclusions. Hardened with the AF-2 and filled with the wollastonite of the Miwoll 10-97 grade, the epoxy compound materials have enhanced wear resistance and adhesion strength and lower friction coefficient. The best result is observed when applying wollastonite modified with a surfactant belonging to the class of quaternary ammonium salts. The wollastonite can be used for practical purposes as a perspective reinforcing agent for epoxy materials with improved wear resistance, enhanced adhesion to metals and reduced friction coefficient.

scholarly journals Comparison of the modifying effect of rice ashand buckwheat husk in epoxy antifriction coatings

2021 ◽  
Vol 17 (4) ◽  
pp. 9-15
Author(s):  
Elena M. Gotlib ◽  
Alina R. Valeeva ◽  
Ekaterina S. Yamaleeva ◽  
Ilya D. Tverdov ◽  
Alexey V. Dolmatov
Keyword(s):  
Wear Resistance ◽  
Friction Coefficient ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Sol Gel ◽  
Optimal Temperature ◽  
Epoxy Coatings ◽  
Antifriction Coatings ◽  
Modifying Effect ◽  
Buckwheat Husk

This paper discusses the issue of utilization of rice and buckwheat husks, a comparison of their modifying effect in epoxy antifriction coatings, for this, the elemental composition of these fillers was determined using X-ray fluorescence analysis, their structure was analyzed by scanning electron microscopy, and the acid-base characteristics of the filler surface were determined by the pH method., the surface area of the pores of the ash of rice and buckwheat husks, their oil absorption were calculated, a sol-gel analysis was carried out to assess the density of the spatial network of filled epoxy coatings, and their wear resistance and hardness were determined. In the course of the research, the optimal temperature for obtaining ash from rice and buckwheat husks was established, which contributes to an increase in wear resistance, hardness and a decrease in the static friction coefficient of filled epoxy coatings. It is shown that the optimal temperature for obtaining rice husk ash is 500 C, and buckwheat husk ash 800 C. At the same time, rice husk ash is a more effective filler for epoxy polymers than buckwheat husk ash, since it increases the hardness of materials and provides a greater decrease in their friction coefficient.

Synthesis and stability of 1-aminoalkylphosphonic acid quaternary ammonium salts

2021 ◽  
Author(s):  
Tomasz K. Olszewski ◽  
Anna Brol
Keyword(s):  
Phosphonic Acid ◽  
Quaternary Ammonium ◽  
Alkylating Agent ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Aminoalkylphosphonic Acid

An effective protocol for quaternization of simple 1-aminoalkylphosphonic acids under basic conditions and using Me2SO4 as convenient alkylating agent is reported. In the course of reaction phosphonic acid quaternary ammonium...

scholarly journals Green Accelerated Synthesis, Antimicrobial Activity and Seed Germination Test of Quaternary Ammonium Salts of 1,2-bis(4-pyridyl)ethane

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2424 ◽  
Author(s):  
Tăbăcaru ◽  
Botezatu ◽  
Horincar ◽  
Furdui ◽  
Dinică
Keyword(s):  
Escherichia Coli ◽  
Triticum Aestivum ◽  
Seed Germination ◽  
Quaternary Ammonium ◽  
Pathogenic Bacteria ◽  
Classical Method ◽  
Triticum Aestivum L ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Radicle Growth

A family of fifteen quaternary ammonium salts (QAs), bearing the 1,2-bis(4-pyridyl)ethane core, were obtained using for the first time two different green methods, such as microwave (MW) and ultrasounds (US) irradiation, with very good yields and in much shorter times compared to the classical method, and an assay on their antimicrobial action against Escherichia coli (E. coli) was carried out. While 12 to 24 hours were required for complete alkylation of 1,2-bis(4-pyridyl)ethane by reactive halogenated derivatives in anhydrous solvent under reflux conditions, MW and US irradiation reduced the reaction time and the desired products were achieved in a few min. One of the aims of this study was to evaluate the antibacterial potential of the synthesized QAs against pathogenic bacteria, along with their impact on germination activity of wheat seeds (Triticum aestivum L.). The antibacterial activity of the QAs against Escherichia coli was explored by determining the minimum inhibitory concentration (MIC). The MIC values varied from 0.312 to 2.5 mg/mL, highlighting the lowest values attained for the derivatives containing methoxy, chlorine and benzofurane functional groups. The viability of aerobic bacteria was determined with the Tetrazolium/Formazan Test, a method that was found to be the best alternative approach with respect to the difuzimetric method. Seeds of Triticum aestivum L. were used for the evaluation of the germination indicators, such as seed germination (SG), the relative seed germination (RSG), the relative radicle growth (RRG), and the seed germination index (GI). The toxicity studies of QAs 1, 4 and 7, at two different concentrations, showed no inhibitory effect on seed germination.

Interaction of water-insoluble quaternary ammonium salts with the hydrated silica surface

1996 ◽  
Vol 32 (6) ◽  
pp. 331-334
Author(s):  
V. V. Turov ◽  
O. A. Zaporozhets ◽  
O. Yu. Nadzhafova ◽  
V. V. Sukhan
Keyword(s):  
Quaternary Ammonium ◽  
Silica Surface ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Hydrated Silica

Curare-like Action of Polymethylene bis-Quaternary Ammonium Salts

Nature ◽  
1948 ◽  
Vol 161 (4097) ◽  
pp. 718-718 ◽  
Author(s):  
R. B. BARLOW ◽  
H. R. ING
Keyword(s):  
Quaternary Ammonium ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts
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