Precipitated silica

About: Precipitated silica is a research topic. Over the lifetime, 1401 publications have been published within this topic receiving 20992 citations.

Highly dispersible precititated silica

Abstract: The present invention relates to a highly disperse precipitated silica which has a high surface area, to a process for preparing it, and to its use as a tire filler for commercial vehicles, motorbikes, and high-speed vehicles.

Effects of different interphases on the mechanical properties of cured silanized silica‐filled styrene–butadiene/polybutadiene rubber blends for use in passenger car tire treads

Abstract: Polybutadiene (BR) and styrene-butadiene (SBR) rubbers containing the same loading of precipitated silica nanofiller were prepared. The silica surfaces were pre- treated with bis(3-triethoxysilylpropyl) tetrasulfide to chemically bond the silica to the rubber. The rubber com- pounds were mixed together for different times and at dif- ferent temperatures to produce SBR/BR blends. The mass fraction and composition values of the interphases in the blends were subsequently determined with modulated-tem- perature differential scanning calorimetry. These properties changed substantially as a function of mixing temperature and mixing time. The hardness, tensile strength, elongation at break, stored energy density at break, tear strength, mod- ulus, abrasion resistance, heat buildup, and loss tangent of the cured blends were measured over a wide range of test conditions. Elongation at break, stored energy density at break, tearing energy, and abrasion resistance benefited from increases in the mass fraction of the interphase. The remaining properties were influenced mainly by the filler loading and mixing time of the two rubber compounds. V C 2009 Wiley Periodicals, Inc. J Appl Polym Sci 113: 1868-1878, 2009

Development of high performance rubber composites from alkoxide-based silica and solution styrene–butadiene rubber

Abstract: The solution SBR and silica-based composites are prepared by hydrolysis of tetraethylorthosilicate in the presence of an organic solution of SBR and n-butylamine as catalyst. Further addition of bis[3-(triethoxysilyl)propyl]tetrasulfide, a silane coupling agent, improves the performance and properties of the composites. All the results are compared with commercial precipitated silica at similar loading conditions. The generated silica particles from this alkoxide route resulted in lower Mooney viscosity of the compound and showed less filler flocculation compared with standard commercial precipitated silica in reference compounds. A detailed dynamic mechanical study also indicated that alkoxide silica in model tire compounds could offer a lower rolling resistance and a higher wet skid resistance compared to the reference. Other properties such as heat build-up, rebound resilience, and hysteresis loss were found to be very promising for alkoxide silica composites, too. The silica particles (aggreg...

Stonework cleaning - using pastes of strong acids and abrasive powders

Abstract: Extremely dirty stone surfaces are cleaned using strong acids eg fluoric acid or one of the complexes such as nitrilo-tri-acetic acid, ethylene-diamino-tetra-acetic acid, 1,2-diamino-cyclohexane-tetra-acetic acid and di-ethylene-triamine penta-acetic acid or their mixts or the alkali polysulphates The conc of the acid is pref 5-15% and the pH is adjusted to pref 9-12 using alkali Pref 10-40% of an inorg powder with large surfaces, eg aerosil, precipitated silica, asbestos powder, perlite, kieselguhr, pref steeped in an org solvent to facilitate paint removal, eg ketones, chlorinated hydrocarbons, esters, dioxane, aniline or their mixt, is added Fluoric or hydrofluosilicic acid with organic powders, eg wood dust, cellulose, ground polyurethane foam, as well as pref 3-5% of a binding medium, eg dextrin, casein, gelatine, etc, may be used Fluoric or hydrofluosilicic acid with pref 6-15% bentonite or clay may also be used The substances made into a paste with 5% water soluble polyvinyl ether, 1-5% of an emulsifier, eg stearate, soap, etc, and 05% of a wetting agent pref sulphate and water The paste is coated onto the stones and after drying removed, mechanically, together with the adhering impurities

A green dual-phase carbon-silica nanohybrid derived from black liquor lignin for reinforcing styrene-butadiene rubber

Abstract: In rubber industry, lignin has been investigated as a potential alternative of fossil-derived carbon black (CB) for several decades. However, due to poor dispersity, big particle size and incompatibility with rubber, lignin cannot achieve the same reinforcing effect as CB by direct dry mixing. Here, a new and green dual-phase carbon-silica nanohybrid (LDPCS) was successfully prepared from black liquor lignin (BLL) and sodium silicate through a simple co-gelation/self-assembly and carbonization process. The preparation mechanism and process as well as the morphology and properties of LDPCS were investigated and discussed in detail. The results indicated that the hydroxymethylation and silane modification of BLL could improve its affinity with SiO2 sols, thus facilitating the co-gelation of BLL and SiO2 sols to inhibit the growth of SiO2 particles. During subsequent acid precipitation, silane modified hydroxymethylated BLL (SiHM-BLL) was self-assembled around SiO2 particles to form nanosized SiHM-BLL-SiO2 hybrids. After carbonization, SiHM-BLL-SiO2 nanohybrids were converted into LDPCS with small primary particle size of 60–90 nm, high specific surface area of 82.19 m2/g, relatively loose secondary aggregation structure and graphitic microcrystals in the carbon framework. With incorporating LDPCS into styrene-butadiene rubber (SBR) by direct dry mixing, LDPCS showed a superior reinforcing capability for SBR as compared with CB, which was ascribed to the nanoscale dispersion of LDPCS, robust C/SiO2 interfaces and high affinity with SBR matrix. This work provided a new insight into the fabrication of novel hybrid nanofiller from lignin and broadened the potential applications of lignin in rubber compounds and beyond.