Showing papers on "Precipitated silica published in 1981"

Precipitated siliceous products

Abstract: A method for producing a precipitated silicon dioxide having a new combination of physical and chemical properties is disclosed. The pigments are produced by acidulating a solution of an alkali metal silicate with an acid under controlled precipitation conditions. The aqueous reaction medium comprising the precipitated silica is then post-conditioned by introducing a second silicate solution into the reaction vessel and thereafter adding additional acid to react with the said second silicate solution. By varying the amount of the silicate employed in the post-conditioning step, a product is obtained which has a unique combination of physical and chemical properties including reduced wet cake moisture content, high surface areas and oil absorptions, improved surface activity, friability, wetting characteristics, and the like. The product has particular utility for use as a rubber reinforcing agent because of its increased surface activity and oil absorption, etc. The product, however, may be used in paints, paper, detergents, dentifrice compositions, molecular sieves, and polymeric compositions. An unexpected discovery of the invention involves the production of a rubber reinforcing silica which has a decreased wet cake moisture content. In one particularly advantageous embodiment, an adduct material, such as aluminum, is added to control the refractive index and surface area of the product.

Inhibition of corrosion of aluminium tubes by toothpastes

Abstract: The tendency of gel toothpastes comprising silica thickeners, such as silica aerogel or precipitated silica, and a fluoride source, such as sodium monofluorophosphate or fluoride, to corrode aluminium tubes can be reduced by incorporating at least 001% by weight sodium or potassium hydroxide or carbonate, so that the pH of the toothpaste is at least 85

Opacified dental cream containing a binary fluorine-providing system

Abstract: An opacified dental cream which effects dental remineralization and reduces caries formation. The opacified dental cream contains a binary fluorine providing system which provides fluorine from sodium monofluorophosphate and from sodium fluoride, a synthetic precipitated silica containing up to about 1% by weight of alumina polishing agent and an opacifying agent.

Mastic asphalt composition

Abstract: A mastic asphalt composition is disclosed which comprises, in addition to the mastic asphalt, 0.2 to 5 wt. % of a crystalline, powdered, synthetic zeolite or zeolite mixture. In addition, the mastic asphalt composition may further contain precipitated silica.

Cerium-containing precipitated silica, process for producing same and masses, hardenable to elastomers, containing same

Abstract: Cerhaltige Fallungskieselsaure gekennzeichnet durch die folgenden physikalisch-chemischen Kenndaten: Cerium-containing precipitated silica characterized by the following physicochemical characteristics: Sie wird hergestellt. It is produced. indem man der Origmalfallungssuspension einer Fallungskieselsaure eine Cer(IV)-Salzlosung zufugt by adding the Origmalfallungssuspension a precipitated silica, a cerium (IV) salt solution Die mit der cerhaltigen Fallungskieselsaure hergestellten. The products produced with the cerium-containing precipitated silica. zu Elastomeren hartbaren Massen auf Basis von Diorganopolysiloxanen weisen ausgezeichnete Warmestabilitat auf. to give elastomers, curable compositions based on diorganopolysiloxanes have excellent heat stability. Zusatzlich wirkt die cerhaltige Fallungskieselsaure als Flammschutzmittel In addition, the cerium-containing precipitated silica acts as a flame retardant

Process for improving the mineral asphalt coatings for streets and paths and products

Abstract: There is provided a process for improving mineral asphaltic coatings for streets and roadways comprising preparing a mixture to be used as the base mineral asphalt coating material, homogeneously mixing in 0.1 to 10 weight % of silica which is either (1) a precipitated silica, (2) a precipitated and spray dried silica or (3) a pyrogenically produced silica and further working this mixture into a mineral asphalt coating for streets and roadways.