scholarly journals Study of the possibility of using diafen FP, sulfenamide C and N,N’-dithiodimorpholine of domestic production in rubber mixtures instead of imported analogues

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.

2009 ◽  
Vol 79-82 ◽  
pp. 2183-2186 ◽  
Author(s):  
Chanchai Thongpin ◽  
C. Sripetdee ◽  
N. Papaka ◽  
N. Pongsathornviwa ◽  
Narongrit Sombatsompop

Silica has been widely used as non-black reinforcing filler, however, the filler-filler interaction has been an important issue. Cure characteristic and mechanical properties of the rubber compound and rubber vulcanizate were affected both by filler-rubber interaction and filler-filler interaction. There have been, presently, a number of natural fillers which are also used as fillers for the rubber, i.e. fly ash, sawdust and zeolite. This work therefore will study the effect of second filler added into the 13% Si-69 treated precipitate silica (PSi) filled natural rubber compounds. It was revealed that the scorch and cure time of the rubber compound increased with the content of treated PSi. This was the effect of excess of the silane treated onto PSi which would agglomerate and form the cluster of polysiloxane and would then be able to absorb vulcanizing accelerator resulting in extending the scorch and cure time of the rubber compounds. However, this effect was over ruled with the reinforcing effect as could be seen by the increasing, with the contents of PSi, of maximum torque and mechanical properties of the vulcanizates. The NR compounded with treated PSi content of 20 phr selected to study the effect of excess silane on the cure characteristic of hybrid fillers NR composite. The addition of sawdust led to longer scorch time and cure time but not much change of the maximum torque. As expected, the modulus of the rubber vulcanizate increased with the sawdust content whereas the tensile strength and elongation at break decreased with the sawdust content. The incorporation of zeolite could accelerate the cure reaction therefore both scorch time and cure time decreased. The maximum torque also increased with the content of zeolite. Both modulus and tensile strength increased with the content of the zeolite whereas elongation at break tended to be unchanged. In the case of using fly ash as the second filler, the cure time tended to be unchanged. However, the maximum torque tended to be increased with the content of fly ash. It was found that the modulus, tensile strength increased but elongation at break decreased. Interestingly, the excess of Si-69 used effect pronouncedly for the addition of zeolite and fly ash cases as the excess silane could promote the interaction between fillers surface and rubber molecule accept for sawdust


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.


2021 ◽  
Vol 899 ◽  
pp. 239-244
Author(s):  
Larisa Yuryevna Zakirova

The article investigates the effect of vulcanizing systems of different activity on the vulcanization and elastic-strength properties of rubber compounds based on ethylene-propylene rubber Keltan . Were taken vulcanizing systems: a mixture of organic peroxide, sulfur and sulfenamide accelerator (1); a mixture of organic peroxide, sulfur and dithiodimorpholine (2); a mixture of organic peroxide, sulfur and thiuram accelerator (3); sulfur and sulfenamide accelerator (4). The vulcanization characteristics (maximum and minimum torques; times of onset, optimum and reaching the maximum speed of vulcanization) were evaluated. Elastic-strength (conditional tensile strength, elongation at break, hardness) properties of rubber compounds and operational (changes in conditional tensile strength, elongation at break after aging in air) were determined. It was found that the vulcanizing system (3) containing sulfur, peroxide in an amount of 7.0 parts by weight and thiuram accelerator imparts the best elastic and strength properties to rubber compounds and leads to their resistance to high temperatures.


1994 ◽  
Vol 67 (4) ◽  
pp. 687-692
Author(s):  
Jin Zhengji ◽  
Gu Jianming ◽  
Liu Weidong ◽  
Zhang Shiqi

Abstract The concepts of optimizability and correlative matrix are proposed and evaluated as a means of correlating the mechanical properties of rubber compounds — elongation at break, tensile strength, set, elastic resilience, tear strength, abrasion loss, aging coefficient, fatigue life, crack initiation, and aged stress — with the rubber formulation variables —NR/SBR/BR composition, accelerator level, sulfur level, antioxidant level, antiozonant level, silica level, and extender oil level.


2020 ◽  
Vol 992 ◽  
pp. 353-358
Author(s):  
N.I. Cherkashina ◽  
O.V. Kuprieva ◽  
N.V. Kashibadze

This study presents the results of an analysis of the influence of joint mechanical activation of a polyimide matrix and tungsten (IV) oxide (WO2) on the mechanical properties of their composites. Mechanical activation of the powder components of the matrix and the filler is performed in a vortex jet mill. The ultimate tensile strength, tensile modulus and relative elongation at break of the composites are all investigated. When using mechanical activation, an increase in tensile strength of 9% is observed with a content of 30 wt.% WO2 filler and of 12% with a content of 70 wt.% WO2 filler compared to composites in which the joint mechanical activation of components is not used. Using scanning electron microscopy, it is shown that the use of mechanical activation by dispersing in a jet-vortex mill made it possible to achieve a uniform distribution of highly dispersed filler based on tungsten dioxide in a polyimide matrix.


2013 ◽  
Vol 13 (2) ◽  
pp. 40-43
Author(s):  
Natalia Meissner ◽  
Władysław M. Rzymski

Abstract In this work, composites made from styrene-butadiene rubber and short fibers were prepared by mixing and investigated. The influence on the vulcanization process and tensile strength properties has been studied and compared with compounds filled with carbon black. The presence of fibers gave shorter curing time and led to a slight increase in tensile strength but decreased the elongation at break of the compound.


2012 ◽  
Vol 488-489 ◽  
pp. 93-97
Author(s):  
Pranut Potiyaraj ◽  
Sittiporn Ngamsurat ◽  
Wasan Poklong

The effects of epoxidized natural rubber as a compatibilizer in modified-montmorillonite filled natural rubber were studied. Natural rubber was compounded with 2, 5 and 10 parts per hundred rubber (phr) of organomodified montmorillonite as a reinforcing filler and cured by using a conventional sulfuric system. Epoxidized natural rubber with 25 and 50 mol% epoxidic units (ENR25 and ENR50, respectively) was used as compatibilizer at the amount of 5, 10 and 15 phr. Rubber compounds were then tested for their curing properties. Test specimens for mechanical testing were prepared by compression molding. The use of montmorillonite as a filler in natural rubber efficiently improved mechanical properties that are tensile strength, modulus, elongation at break, tear strength and hardness, especially with the small amount of montmorillonite. This is supposed to be related to intercalation and exfoliation process. The increasing amount of montmorillonite caused the filler to be agglomerated thus the reinforcing efficiency was reduced and some mechanical properties were dropped. It was further founded that epoxidized natural rubber compatibilized montmorillonite filled natural rubber effectively. As the amount of epoxidized natural rubber increased, the mechanical properties tended to increase. The presence of epoxidized natural rubber improved filler-rubber interaction and filler dispersion. The compatibilizing efficiency of ENR25 was slightly superior to that of ENR50. This is because ENR 25 contains more double bonds than ENR 50 hence higher strain-induced crystallinity is occurred


2013 ◽  
Vol 844 ◽  
pp. 272-275 ◽  
Author(s):  
Karnda Sengloyluan ◽  
Kannika Sahakaro ◽  
Jacques W.M. Noordermeer

Epoxidized natural rubber (ENR) and bis-(3-triethoxysilylpropyl) tetrasulfide (TESPT) were used to improve the properties of silica-filled NR. The use of ENR containing 51 mol% epoxide groups (ENR-51) as a compatibilizer without TESPT was optimized at 7.5 phr, based on the results of Payne effect and tensile strength. By using 7.5 phr of ENR-51 with varying amounts of TESPT in a range of 2 to 5 wt% relative to the silica, the properties of compounds were compared to those of the ones with optimum TESPT content (i.e. 8.6 wt% relative to the silica) and without. The addition of TESPT to the ENR-51 compatibilized silica-filled NR compound had no effect on Mooney viscosity but lowered the Payne effect to the same level as that of the silica/TESPT compound, and significantly decreased both scorch and optimum cure times. The silica-filled NR with ENR and the small amount of TESPT combination showed a further increase in tensile strength to match that of the optimized silica/TESPT system, while maintained the elongation at break. This work demonstrates that the use of ENR as compatibilizer clearly enhances the properties of silica-filled NR compounds, and that such properties can be further improved by adding TESPT at a half or less amount of TESPT normally needed for silica-filled compounds.


2014 ◽  
Vol 42 (4) ◽  
pp. 290-304
Author(s):  
Rajarajan Aiyengar ◽  
Jyoti Divecha

ABSTRACT The blends of natural rubber (NR), polybutadiene rubber (BR), and other forms of rubbers are widely used for enhancing the mechanical and physical properties of rubber compounds. Lots of work has been done in conditioning and mixing of NR/BR blends to improve the properties of its rubber compounds and end products such as tire tread. This article employs response surface methodology designed experiments in five factors; high abrasion furnace carbon black (N 330), aromatic oil, NR/BR ratio, sulfur, and N-oxydiethylene-2-benzothiazole sulfenamide for determination of combined and second order effects of the significant factors leading to simultaneous optimization of the NR/BR blend system. One of the overall optimum of eight properties existed at carbon 44 phr, oil 6.1 phr, NR/BR 78/22 phr with the following values of properties: tensile strength (22 MPa), elongation at break (528%), tear resistance (30 kg/mm), rebound resilience (67%), moderate hardness (68 International rubber hardness degrees) with low heat buildup (17 °C), permanent set (12%), and abrasion loss (57 mm3). More optimum combinations can easily be determined from the NR/BR blend system models contour plots.


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