scholarly journals THE INFLUENCE OF POWDER SHUNGYTES ON PROPERTIES OF OIL-AND BENZO RESISTANT RUBBERS

Author(s):  
Nikolay F. Ushmarin ◽  
Egor G. Efimovskii ◽  
Nina N. Petrova ◽  
Sergei I. Sandalov ◽  
Nikolay I. Kol'tsov

In the article two rubber mixtures are studied: rubber 7NO-68-1SK based on a combination of butadiene-nitrile caoutchouc BNKS-18AMN with chloroprene caoutchouc neoprene W and rubber 81-453 based on a combination of butadiene-nitrile caoutchouc BNKS-40AMN, butadiene caoutchouc SKD, butadiene-methylstyrene caoutchouc SKMS-30 ARK and sevilene 11808-340. The purpose of the study was to improve the physical-mechanical and operational properties of both rubber mixtures by using fine powdered schungites Taurit TS-D, Psh-5 and PSH-20 in their composition. To assess the kinetics of vulcanization of rubber mixtures, the following were determined: the minimum and maximum torques; start time, optimum time, time achieving maximum vulcanization rate and maximum of vulcanization rate. To assess the physical-mechanical properties, we determined: the conditional tensile strength; elongation at break; hardness and relative residual deformation after compression. To evaluate the performance properties of rubbers, the following was determined: the change in the relative tensile strength; change in elongation at break and change in mass after aging of vulcanizates in a standard liquid SZHR-1, isooctane + toluene mixture, as well as in gasoline and industrial oil I-20A. It is shown that for the rubber mixture 7-NO-68-1SK a partial replacement of carbon blacks P 803 on the schungite PSH-5 in an amount of 15 parts by weight leads to an improvement in the rheometric parameters, physico-mechanical and operational properties of vulcanizates. For the rubber mixture 81-453, partial replacement of the persil 175 on shungite PSH-5 also allows improving the rheometric properties and increasing the physico-mechanical and operational parameters.

2019 ◽  
Vol 59 (7) ◽  
pp. 63-68
Author(s):  
Nikolay F. Ushmarin ◽  
◽  
Evgeny N. Egorov ◽  
Nikolay I. Kol'tsov ◽  
◽  
...  

The article examines the oil-and-petrol resistant rubber mixture of type 7NO-68-1SK based on the combination of BNKS-18AMN grade butadiene-caoutchouc with polychloroprene caoutchouc of brand neoprene W. The effect of replacing imported burnt magnesia brand Remag AC on domestic burnt magnesia technical grade B on the properties of the rubber compound and vulcanizate was studied. The rubber mixture was prepared on a laboratory roll mill LB 320 160/160, and then its standard samples were vulcanized at 150 °C for 30 minutes in a two-story electrically heated press of the VP 400-2E brand. To establish the plasto-elastic properties of rubber mixture on the Mooney viscometer, MV 3000 was determined: the start time of the vulcanization, the time to reach the vulcanization mode, the initial maximum viscosity. To assess the kinetics of vulcanization of the rubber mixture on the rheometer MDR 3000 was determined: the start time of vulcanization, the time to reach the optimum vulcanization, the maximum torque. To assess the physicomechanical properties of rubber, the following were determined: conditional tensile strength; elongation at break; hardness; tear resistance and relative residual deformation under compression in accordance with the standards in force in the rubber industry. To assess the performance properties of rubber, changes in its mass were determined after aging in a mixture of isooctane + toluene, as well as standard liquid SJR–1. It has been shown that the introduction of burnt magnesia technical grade B into the rubber mixture does not lead to technological complications, magnesia is well distributed in the rubber matrix, and the magnesia agglomerates were not found on the rubber mixture sections. Replacement magnesium oxide m. Remag AC on burnt magnesia technical grade B has an impact on the plasto-elastic and rheometric properties of the rubber mixture. However of physicomechanical and operational properties vulcanizates of rubber mixture containing magnesium oxide m. Remag AC and burnt magnesiatechnical grade B, have almost the same values.


Author(s):  
Nikolay F. Ushmarin ◽  
Evgeny N. Egorov ◽  
Nikolay I. Kol'tsov

The aim of the work is to study the effect of hollow corundum, glass and pomegranate ceramic microspheres on the rheometric characteristics of aggressive resistant rubber mixtures and the physicomechanical parameters of their vulcanizates to determine of the content of fillers of this type, which provides an improvement in the priority properties of products and, as a result, an increase in their durability. The objects of research were two rubber mixtures intended for compression molding and injection molding. The compression molding mixture is based on a combination of nitrile butadiene, isoprene and butadiene-α-methyl styrene caoutchoucs with colloidal silicic acids as the main fillers. And the injection molding mixture is based on a combination of synthetic isoprene and butadiene rubbers filled with chalk, P234 carbon black and carbon 100. We used hollow corundum (HMC-L), glass (MS-V), and pomegranate ceramic (MVMD-170) microspheres. The rheometric properties of the rubber compounds were evaluated by the values of the minimum and maximum torques, the duration of the induction period, the time to reach the technological optimum, and the maximum vulcanization rate. When testing vulcanizates, conditional tensile strength, elongation at break, tear resistance, hardness, abrasion and rebound elasticity were determined. Priority indicators were also determined that correlated to the greatest extent with the durability of the products during operation - relative changes in conditional tensile strength and elongation at break, hardness after heat aging in air and standard liquid SZhR-1, change in mass of samples after swelling in industrial oil I-20A and Nefras S-80/120. For a mixture for compression molding, the effect of the type of microspheres introduced at a dosage of 5 parts by mass per 100 parts by mass caoutchoucs, on the properties of unvulcanized mixtures and vulcanizates was studied. It was found that the rubber mixture with glass microspheres is somewhat below in vulcanization activity, and its vulcanizate in terms of abrasion resistance, heat aging, especially in air, is inferior to two mixtures and rubbers with corundum and pomegranate microspheres. In the second mixture, we tested corundum microspheres with a dosage of 3.0 to 7.0 parts by mass per 100 parts by mass of caoutchoucs while reducing by the appropriate amount of carbon black. It was found that with an increase in the dosage of microspheres, a decrease in the vulcanization activity of the mixture, minimum and maximum torques, and also their difference is observed, which indicates a slight decrease in the degree of crosslinking of rubbers. The consequence is an increase in relative lengtheningof the vulcanizates. To the least extent, this effect manifests itself with the introduction of corundum microspheres in a dosage of 3 parts by mass. Thus, the advantage of rubbers with microspheres is reduced abrasion, higher tear resistance while maintaining resistance to the action of physically and chemically aggressive environments at the level of rubbers that do not contain microspheres.


2015 ◽  
Vol 35 (1) ◽  
pp. 79-88 ◽  
Author(s):  
Keshak Babu ◽  
Achinta Bera ◽  
Kamlesh Kumari ◽  
Ajay Mandal ◽  
Vinod Kumar Saxena

Abstract Biodegradable blended films from methylcellulose (MC) and potato starch (PST) have been developed by the casting process. In the present work the influences of concentrations of MC and PST on rheological properties, swelling, mechanical properties such as tensile strength, percentage elongation at break and water vapor transmission rate (WVTR) of the prepared blended films have been studied. Fourier transform infrared (FTIR) analysis of pure MC, PST, their mixture and the mixture with glutaraldehyde and urea was performed to investigate the interactions in blended films. The blended films of MC and PST showed an increase in tensile strength due to the cross linking reactions of the amylopectin molecule of PST in the physical gel state. The change of percentage elongation at break increased with MC concentration and the opposite trend was found in the case of the WVTR due to the network structure of the blended films. The blended films showed a large improvement in the abovementioned properties compared with each single component, due to the interaction formed between hydroxyl groups of PST and the methoxy groups of MC. Experiments were also conducted to investigate the controlled urea release through blended films and the kinetics of the process. Interesting results were found with the prepared MC and PST blended films.


2019 ◽  
Vol 57 (2) ◽  
pp. 123-129
Author(s):  
Egor G. Efimovskiy ◽  
◽  
Nikolay F. Ushmarin ◽  
Sergey I. Sandalov ◽  
Nikolay I. Kol'tsov ◽  
...  

The article presents the results of a study of various rubber compounds based on rubbers containing, in the composition, made by FGUP GosNIIOHT diafen FP, sulfenamide C and N,N'-dithiodimorpholine instead of imported analogues. Rubber compounds were made on a laboratory rubber mixer SKI-3L with Intermix rotors. After a day at room temperature, the rubber mixtures were vulcanized on a vacuum compression machine of column type a firm Panstone 3RT. The main technological indicators of rubber mixtures after their manufacture on the rolls were: ductility, ring modulus and density. These indicators characterize the processability of rubber mixtures in the manufacture of products from them. For the obtained vulcanizates, the elastic-deformation properties (conditional tensile strength, relative elongation at break, Shore A and ISO hardness, bond strength with metal at tearing, and abrasion resistance) were determined by standard methods. To assess the performance properties of rubbers, changes in conditional tensile strength, relative elongation at break, hardness, volume and mass after rubbers aging in corrosive media, as well as relative residual deformation of compression, temperature limit of brittleness and frost resistance were determined. The possibility of using diaphene FP, sulfenamide C and N,N'-dithiodimorpholine made by FSUE "GosNIIOHT" as part of various rubber mixtures instead of imported analogs is shown. The obtained rubbers according to the technological, elastic-deformation and operational properties comply with the requirements. These rubbers can be used for the manufacture of rubber-technical products with a special set of elastic-deformation and performance properties, and domestic ingredients manufactured by the Federal State Unitary Enterprise GosNIIOHT can be introduced into production.


2011 ◽  
Vol 230-232 ◽  
pp. 103-106
Author(s):  
Hai Tao Liu ◽  
Jing Feng Zhang ◽  
Yi Guang Tian ◽  
Xue Jun Weng ◽  
Shi E Lin

Mechanical and vulcanization behaviors of styrene-butadiene rubber(SBR)/N330 and SBR/N330/PBMCN nanocomposites were investigated via partial replacement of SBR with pyrophyllite based modified composite nanopowder(PBMCN), which were prepared by melt mixing procedure. Results show a fairly good dispersion of PBMCN in the SBR/N330/PBMCN composites characterized by field-emission scanning electron microscope (FESEM). Mechanical and vulcanization behaviors of the as-abtained pruducts were measured according to GB/T 528-2009 and GB/T 16584-1996, respectively. Near properties in tensile strength, elongation at break and vulcanization behaviors were observed in SBR/N330/PBMCN nanocomposites when SBR was partially replaced by PBMCN for 8% mass fraction. A possible reinforcement mechanism of PBMCN to SBR/N330/PBMCN nanocomposites is also dicussed based on the experiment.


2019 ◽  
pp. 96-101
Author(s):  
M. N. Nagornaya ◽  
A. V. Myshlyavtsev ◽  
E. A. Strizhak

The influence of carbon black N121 and N326, oxidized by active oxygen forms, in comparison with the influence of channel carbon black K 354 on the properties of rubbers based on butyl rubber was investigated. It was revealed that the introduction of oxidized carbon black samples into the composition of rubber compounds allows increasing the start time of rubber mixture scorching from 8.82 to 11.17 minutes, increasing the level of conventional tensile strength from 15, 52 to 16.68 MPa. It has been established that using rubber based on butyl rubber as a filler for carbon black N121 or N326, oxidized with 30% hydrogen peroxide, makes it possible to obtain rubber with a surface energy similar to rubber K 354.


2019 ◽  
Vol 60 (10) ◽  
pp. 81-87
Author(s):  
Nikolay F. Ushmarin ◽  
◽  
Lyudmila Yu. Tsareva ◽  
Ksenia A. Konnova ◽  
Maria V. Yakimova ◽  
...  

The article investigates the influence of technological additives and peroxides on the properties of two rubber mixtures based on ethylene-propylene caoutchouc of marking SKEPT-40. The main properties were: rheometric (maximum and minimum torques; start, optimum and maximum vulcanization rates; maximum vulcanization rates), physical and mechanical (conditional tensile strength, elongation at break, hardness) and operational (changes in conditional strength at tensile, elongation at break and hardness after aging in air). The resistance of rubbers to the action of high temperatures by methods of differential thermal and thermogravimetric analysis was studied. As technological additives, MA-L22, Struktol WS180, Zincolet BB 222 and Struktol A89 were used. Vulcanizing agents were peroxides: Novoperox BP-40, Percodox BC-FF, Dicumyl Peroxide (DK), Chemanox PX1 and Dicumyl Peroxide DCP 99. The studies were carried out for two rubbers, one of which is intended for the manufacture of molded products, and the second rubber – for sealing profiles. It was shown that the technological additive Zincolet BB 222 increases the vulcanization rate of rubber mixture for molded products. All technological additives used have practically no effect on the conditional tensile strength and hardness vulcanizates of molded products, increasing their elongation at break. The smallest changes in the physical and mechanical properties are characterized by the vulcanizate, which contains the technological additive Zincolet BB 222. Technological additives practically do not affect the process of vulcanization of the rubber mixture and slightly affect the process of destruction of rubber during aging. Of the investigated technological additives Zincolet BB 222 is more conducive to improving the thermal properties of rubber. It has been established that Novoperox BP-40 and Chemanox PX1 peroxides increase the rate of vulcanization of the rubber mixture for sealing profiles. For vulcanizates of this rubber mixture, when Novoperox BP-40 and Chemanox PX1 is replaced with other peroxides, a decrease in the conditional tensile strength, hardness and an increase in the elongation at break are observed. With aging in air, changes in the physicomechanical properties of the vulcanizates of the rubber mixture variants containing Novoperox BP-40 and Chemanox PX1 are insignificant and close to each other.


2015 ◽  
Vol 1125 ◽  
pp. 271-275 ◽  
Author(s):  
Reza Arjmandi ◽  
Azman Hassan ◽  
M.K. Mohamad Haafiz ◽  
Zainoha Zakaria

The objective of this study is to investigate the effect of partial replacement of montmorillonite (MMT) with microcrystalline cellulose (MCC) on the tensile and morphology properties of polylactic acid (PLA) composites. PLA composites reinforced with hybrid MMT/MCC were prepared by solution casting. Based on our previous study, tensile strength exhibited that the optimum MMT content in the PLA/MMT is 5 phr. Therefore, partial replacement of MMT with MCC was performed at 5 phr of filler content in order to produce PLA/MMT/MCC hybrid composites. Fourier transform infrared spectroscopy revealed some polar interaction between fillers and PLA matrix. Young’s modulus of the PLA/MMT/MCC hybrid composites increased gradually with increasing MCC filler in the hybrid composites and was higher than PLA/MMT nanocomposites. However, the highest tensile strength of hybrid composites was obtained at 4 phr MMT and 1 phr of MCC filler (~26 MPa), which was lower than optimum formulation of PLA/MMT nanocomposites. Interestingly, the percent elongation at break of the hybrid composites were higher than that of PLA/MMT nanocomposites; increased significantly from ~10 to ~58 %. Field emission scanning electron microscopy indicated the aggregation of MCC and the presence of some cracks in the PLA hybrid composites, resulted in decrease of the tensile strength.


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