Precipitated silica

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

The synthesis of novel zeolite Y nanoparticles using mesoporous silica with a temperature controlling method

Abstract: Porous nanoparticles aggregated from primary zeolite sodium-form Y (NaY) nanocrystals were hydrothermally synthesised using porous precipitated silica as the silica source via a three-stage temperature control strategy, using tetramethylammonium hydroxide (TMAOH) as an organic additive. The synthesised samples were characterised using powder X-ray diffraction, energy dispersive X-ray spectroscopy, nitrogen (N2) sorption, and particle size analysis. The results show that the zeolite aggregate particles with sizes of 150–600 nm were composed of highly crystalline zeolite NaY nanoparticles in the size range of 2–4 nm. The particle sizes of porous aggregates can be readily tuned by varying the additive amounts of the zeolite precursor gel without notably changing the sizes of the primary zeolite nanocrystals. The N2 sorption results show that the zeolite NaY aggregate particles had high microporosity with no clear mesoporosity. The zeolite particles exhibited very good resistance to mechanical conglomeration and remained intact after several months.

Properties of Natural Rubber Vulcanizates/Nanosilica Composites Prepared Based on the Method of In-situ Generation and Coagulation

Abstract: Using the characteristics of silica sol dispersing well in water and easy formation of silica gel when the silica sol is heated, by mixing a system of concentrated natural rubber latex and silica sol, the silica sol can in-situ generate SiO2 particles when heated. After coagulation of the mixed system, natural rubber/nanosilica composites C(NR/nSiO2) were obtained. The composites C(NR/nSiO2) and their vulcanizates were studied using a rubber processing analyzer (RPA), dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). The influence of silica contents on the C(NR/nSiO2) vulcanizates mechanical properties, cross-linking degree, Payne effect, dissipation factor (tanδ), and the particle size and dispersion of SiO2 in NR were investigated. The results obtained were compared with the NR/SiO2 composites based on traditional dry mixing of bale natural rubber and precipitated silica (white carbon black). The results showed that when using a sulfur curing system with a silica coupling agent ...

Developments in silica usage for decreased tyre rolling resistance

Abstract: Tyre material designers appear to be successful in obtaining both low rolling resistance and high wet performance, using precipitated silica together with solution polymers in tyre treads. There is still a need to improve rolling resistance further. Again, precipitated silica could be part of the answer. Compounding with precipitated silicas, particularly of high dispersibility, improves rolling resistance and other tyre properties of many parts of a tyre. We explain that it could be used there to help to meet new low rolling resistance requirements, not only in passenger tyres, but also in other tyre lines.

Tire containing internal cord reinforced rubber layer

Abstract: A tire which contains an internal layer of cord reinforced rubber composite is disclosed. The rubber composite comprises, based upon parts by weight per 100 parts by weight rubber (phr), from 0 to 70 phr of a natural cis 1,4-polyisoprene rubber, 20 to 95 phr of a synthetic cis 1,4-polyisoprene rubber, and 2 to 20 phr of a trans 1,4-polyisoprene rubber; and a rubber reinforcing filler in an amount of from 20 to 70 phr, the filler comprising carbon black, or silica such as precipitated silica, or a combination of carbon black and silica which contains from 5 to 45 phr of silica. The internal layer of cord reinforced rubber composite further comprising at least one cord encapsulated by the rubber composite, wherein the cord comprises at least one filament selected from a brass coated steel filament, or a nylon, polyester, rayon or polyaramid filament.