Effects of Nano-Structure of Silica on Dynamic Properties of Styrene-Butadiene Rubber

2007 ◽  
Vol 555 ◽  
pp. 473-478 ◽  
Author(s):  
N.L. Lazić ◽  
J. Budinski-Simendić ◽  
S. Ostojić ◽  
M. Kićanović ◽  
M.B. Plavšić

Properties of four materials based on styrene-butadiene rubber (SBR), one without filler and the other three with the same amount but different types of silica fillers, are investigated. The fillers used are Vulkasil S and two new fillers, differing in nano-structures: specific surface area and particle aggregate morphology. All other components in the material formulations are the same as well as the procedures of material preparation. Thermal and thermo-mechanical properties of all four materials are investigated by modulated differential scanning calorimetry (MDSC) and dynamic mechanical analysis (DMA). Morphology of the materials is studied using scanning electron microscopy (SEM). The results for glass transition temperature (Tg ) of gum rubber and three filled rubbers, obtained by MDSC are for all four materials Tg = -50±1 0C, and by DMA loss tangent measurements also for all of them Tg = -29±1 0C. It indicates no significant influence of active silica fillers on the rubber network segment dynamics, in the temperature range close to Tg of SBR. But, at higher temperatures MDSC gives insights into dynamic transitions that are under the influence of filler interactions and sensitive to filler structure. The difference in Tg results obtained for the same material by MDSC and DMA can be understood in terms of different sensitivity of network segment dynamics to conditions provided by those two measuring methods.

2019 ◽  
pp. 000-000
Author(s):  
Qing-Yuan Han ◽  
Xu Li ◽  
Yu-Chun Li ◽  
You-Ping Wu

ABSTRACT The compatibility between solution polymerized styrene–butadiene rubber (SSBR 2466) and natural rubber (NR) is characterized by differential scanning calorimetry and dynamic mechanical thermal analysis. The single glass transition in the entire temperature range of all NR/SSBR blends and good correlation between Tg and SSBR fraction prove the excellent compatibility between SSBR 2466 and NR. With increasing SSBR content, a reduced Payne effect, more homogeneous dispersion of silica, stronger rubber–filler interaction, and more silica selectively distributed in the SSBR phase were determined via rubber-processing analysis, transmission electron microscopy, bound rubber, and thermogravimetric analysis, respectively. The high vinyl content, low styrene content, and end-functionalized structure of SSBR play vital roles in promoting its compatibility with NR and a stronger rubber–silica linkage. The resulting increased tan δ at 0 °C and low tan δ at 60 °C indicates good wet-skid resistance and low rolling resistance by blending SSBR 2466, and 70/30 NR/SSBR is the best balance for producing a “green tire” tread.


Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2413
Author(s):  
Mariapaola Staropoli ◽  
Vincent Rogé ◽  
Enzo Moretto ◽  
Joffrey Didierjean ◽  
Marc Michel ◽  
...  

The improvement of mechanical properties of polymer-based nanocomposites is usually obtained through a strong polymer–silica interaction. Most often, precipitated silica nanoparticles are used as filler. In this work, we study the synergetic effect occurring between dual silica-based fillers in a styrene-butadiene rubber (SBR)/polybutadiene (PBD) rubber matrix. Precipitated Highly Dispersed Silica (HDS) nanoparticles (10 nm) have been associated with spherical Stöber silica nanoparticles (250 nm) and anisotropic nano-Sepiolite. By imaging filler at nano scale through Scanning Transmission Electron Microscopy, we have shown that anisotropic fillers align only in presence of a critical amount of HDS. The dynamic mechanical analysis of rubber compounds confirms that this alignment leads to a stiffer nanocomposite when compared to Sepiolite alone. On the contrary, spherical 250 nm nanoparticles inhibit percolation network and reduce the nanocomposite stiffness.


Author(s):  
Oleg K. Garishin ◽  
◽  
Anton Y. Beliaev ◽  

The work is devoted to the study of nanocomposites based on synthetic (styrene-butadiene) rubber with different fillers not previously used. The issue of using composites with alternative fillers is being investigated. The results of experimental testing and analysis of thermo-visco-elastic behav-ior of styrene-butadiene rubbers filled by various mineral particles of micro and nanosize, as well as pyrolysis products of organic food waste, are presented. The filled elastomers discussed in this work are mainly used in the tire industry to improve the performance of tires. All samples were tested on a dynamo-mechanical analyzer (DMA). Temperature and frequency dependences of the dynamic modulus and loss modulus are plotted for each of the composites. The frequency charac-teristics corresponded to the real range of rotation speeds of the car wheel, and the temperature var-ied from –50 to +50ºC. A comparative analysis of the results obtained was carried out. The struc-tural mechanisms of the filler are not investigated. It is assumed that the principles of operation of the investigated fillers at the structural level are similar to those described in many works for clas-sical fillers. Based on the test results a conclusion about the preferable operating conditions for the considered materials was made.


2016 ◽  
Vol 89 (2) ◽  
pp. 262-271 ◽  
Author(s):  
Qingguo Wang ◽  
Jingrui Liu ◽  
Quande Cui ◽  
Xiao Xiao

ABSTRACT How to improve the wet skid resistance of rubber composites for tire tread while decreasing the rolling resistance is very important for both rubber researchers and industry. The irradiation-vulcanized elastomer particles, ultrafine fully-vulcanized powder nitrile butadiene rubber (UFPNBR), having the diameter of about 80 nm, were studied on modifying the dynamic mechanical properties of styrene butadiene rubber/natural rubber (SBR/NR) composites for tire tread. It is notable that the UFPNBR particles can improve the tanδ values of SBR/NR composites in a temperature range from −10 to 20 °C and decrease the tanδ values in the temperature range from 50 to 70 °C simultaneously, which indicates that the UFPNBR particles not only can improve the wet skid resistance but also can reduce the rolling resistance of the SBR/NR composites. On the other hand, the UFPNBR-modified SBR/NR composites also have good dynamic properties for safety operation of tires at high temperature and good tensile strength, tear strength, and fatigue properties in the range of 8 phr UFPNBR loadings.


2020 ◽  
pp. 009524432093398
Author(s):  
Fuquan Deng ◽  
Hua Jin ◽  
Li Zhang ◽  
Yuxin He

Polymeric foam with lightweight and higher impact strength has been used in many fields due to cost reduction and higher toughness. However, it is often difficult to improve their mechanical property especially tear strength. Here, a double foaming system was designed to increase the tear strength of the foamed ethylene–propylene–diene monomer, styrene–butadiene rubber, and thermoplastic rubber (EPDM/SBR/TPR) materials. The cell size of EPDM/SBR/TPR foam and cell distribution were investigated by scanning electron microscopy, which showed that the cells present a bimodal structure. Besides, the tear strength can reach up to 10 N/mm when the density is about 0.40 g/cm3, which is much superior to those of most engineering plastic foams. Meanwhile, the crystallization property of EPDM/SBR/TPR foams was also demonstrated by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry, which indicates that the double foaming system can reduce the crystallization of EPDM/SBR/TPR molecular chains. In addition, the variation of thermal conductivity values depends on the gradual decrease effect of the cell size.


2016 ◽  
Vol 49 (4) ◽  
pp. 298-314 ◽  
Author(s):  
Sara Estagy ◽  
Saeed Ostad Movahed ◽  
Soheil Yazdanbakhsh ◽  
Majid Karim Nezhad

The market for commercial polymer blends has grown steadily. A good blend should have strong interphases between different parts of the constituted polymers. Lack of strong interphases is a classical problem of the blend industry. Ethylene-propylene-diene monomer rubber (EPDM)/styrene-butadiene rubber (SBR) blends have a very good aging resistance and good compression sets. However, these rubbers are partially miscible. To improve the miscibility of EPDM and SBR in their blends, a Lewis acid, AlCl3, was used to form EPDM–g–SBR copolymer through Friedel–Crafts reactions. The existence of covalent bonds between EPDM and SBR macromolecules was studied by the cure traces of the blends, that is, ΔTorque, Fourier transform infrared spectrums, differential scanning calorimetry (DSC) heat flow curves, thermogravimetric analysis curves, and scanning electron (SEM) micrographs. Subsequently, several blends with EPDM/SBR ratio of 40/60 and with various AlCl3 amounts were prepared and after curing, their mechanical properties were measured and compared. The results showed covalent bonds formed between SBR–EPDM and SBR–SBR macromolecules. An exothermic change in heat flow in the DSC curve was observed around 111.28°C, which can be attributed to the formation of carbocations in Friedel–Crafts reactions. Adding 2 phr AlCl3 had an efficient effect on EPDM–SBR and or SBR–SBR linkages. The mechanical properties of the cured blends, that is, tensile strength were lower when compared with corresponding values for prepared compound with SBR. Excellent compatibility between the two polymers and strong interphases were observed in SEM micrograph of the cured blend with 1 phr AlCl3.


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