Styrene-butadiene

About: Styrene-butadiene is a research topic. Over the lifetime, 5568 publications have been published within this topic receiving 62099 citations. The topic is also known as: styrene-butadiene rubber & SBR.

Mechanical performance of styrene-butadiene-rubber filled with carbon nanoparticles prepared by mechanical mixing

Abstract: Reinforcement of styrene-butadiene-rubber (SBR) was investigated using two different carbon blacks (CBs) with similar particle sizes, including highly structured CB and conventional CB, as well as multi-walled carbon nanotube (MWCNT) prepared by mechanical mixing. The attempts were made to examine reinforcing mechanism of these two different classes of carbon nanoparticles. Scanning electron microscopy and electrical conductivity measurement were used to investigate morphology. Tensile, cyclic tensile and stress relaxation analyses were performed. A modified Halpin–Tsai model based on the concept of an equivalent composite particle, consisting of rubber bound, occluded rubber and nanoparticle, was proposed. It was found that properties of CB filled SBR are significantly dominated by rubber shell and occluded rubber in which molecular mobility is strictly restricted. At low strains, these rubber constituents can contribute in hydrodynamic effects, leading to higher elastic modulus. However, at higher strains, they contribute in stress hardening resulting in higher elongation at break and higher tensile strength. These elastomeric regions can also influence stress relaxation behaviors of CB filled rubber. For SBR/MWCNT, the extremely great inherent mechanical properties of nanotube along with its big aspect ratio were postulated to be responsible for the reinforcement while their interfacial interaction was not so efficient.

Reinforcing styrene butadiene rubber with lignin-novolac epoxy resin networks

Abstract: In this study, lignin-novolac epoxy resin networks were fabricated in the styrene butadiene rubber (SBR) matrix by combination of latex compounding and melt mixing. Firstly, SBR/lignin compounds were co-coagulated by SBR latex and lignin aqueous solution. Then the novolac epoxy resin (F51) was added in the SBR/lignin compounds by melt com- pounding method. F51 was directly cured by lignin via the ring-opening reaction of epoxy groups of F51 and OH groups (or COOH groups) of lignin during the curing process of rubber compounds, as was particularly evident from Fourier trans- form infrared spectroscopy (FTIR) studies and maximum torque of the curing analysis. The existence of lignin-F51 net- works were also detected by scanning electron microscope (SEM) and dynamic mechanical analysis (DMA). The structure of the SBR/lignin/F51 was also characterized by rubber process analyzer (RPA), thermogravimetric analysis (TGA) and determination of crosslinking density. Due to rigid lignin-F51 networks achieved in SBR/lignin/F51 composites, it was found that the hardness, modulus, tear strength, crosslinking density, the temperature of 5 and 10% weight-loss were signif- icantly enhanced with the loading of F51.

Mechanics of short fibers in filled styrene‐butadiene rubber (SBR) composites

Abstract: Different short fibers (glass, carbon, cellulose, polyamide, and polyester with aspect, length/diameter, ratio of 600, 860, 500, 83, and 330 respectively) were added to styrene-butadiene rubber (SBR) matrix filled with an inorganic semireinforcing mineral (sepiolite). In all cases, 18 parts by volume of fiber per 100 parts by mass of rubber were added. The fiber orientation attained (more than 60%) was evaluated by a ratio of directional mechanics on uncured samples. In glass and carbon fiber composites, because of decreases in fiber aspect ratio after mixing (10 and 35 respectively), no improvements in properties were obtained. The presence of fibers yields a large increase in green strength, stress at low strain, and tear strength. Logically, the elongation at break diminishes. The uncured and cured properties present a remarkable anisotropy. The adhesive employed (resorcinol-formaldehyde) to increase fiber-to-matrix adhesion enhanced the composite properties, especially in the case of polyester fiber composites. Thus, for polyester fiber composites, green strength became 15.85 kg/cm2; stress at 25% strain, 10.2 MPa; tensile strength, 6.3 MPa; elongation at break, 36%; tear strength, 70 N; and swelling in longitudinal direction, 1.06.

The Synergy of Double Cross-linking Agents on the Properties of Styrene Butadiene Rubber Foams.

Abstract: Sulfur (S) cross-linking styrene butadiene rubber (SBR) foams show high shrinkage due to the cure reversion, leading to reduced yield and increased processing cost. In this paper, double cross-linking system by S and dicumyl peroxide (DCP) was used to decrease the shrinkage of SBR foams. Most importantly, the synergy of double cross-linking agents was reported for the first time to our knowledge. The cell size and its distribution of SBR foams were investigated by FESEM images, which show the effect of DCP content on the cell structure of the SBR foams. The relationships between shrinkage and crystalline of SBR foams were analyzed by the synergy of double cross-linking agents, which were demonstrated by FTIR, Raman spectra, XRD, DSC and TGA. When the DCP content was 0.6 phr, the SBR foams exhibit excellent physical and mechanical properties such as low density (0.223 g/cm3), reduced shrinkage (2.25%) and compression set (10.96%), as well as elevated elongation at break (1.78 × 103%) and tear strength (54.63 N/mm). The results show that these properties are related to the double cross-linking system of SBR foams. Moreover, the double cross-linking SBR foams present high electromagnetic interference (EMI) shielding properties compared with the S cross-linking SBR foams.

Thiol‐containing ionic liquid for the modification of styrene–butadiene rubber/silica composites

Abstract: To introduce thiol–ene chemistry in the modification of composites by ionic liquid (IL), a novel functional IL, 1-methylimidazolium mercaptopropionate (MimMP), was synthesized and investigated as a modifier for styrene–butadiene rubber/silica composites. MimMP could be hydrogen-bonded with silica and react with the double bonds of rubber chains via thiol–ene chemistry. The filler networking, curing behavior, filler dispersion, crosslink density, and mechanical performance were fully studied. The filler networking in the uncured rubber compounds was effectively restrained. The vulcanization was largely accelerated by MimMP. The interfacial interaction was quantitatively evaluated and found to consistently increase with increasing MimMP. The mechanical performance and abrasion resistance of the modified vulcanizates improved considerably. The remarkable improvements were mainly ascribed to the improved interfacial structure comprised of MimMP–silica hydrogen bonding and MimMP–rubber covalent bonds via thiol–ene chemistry. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011