Provided is a hydrophilic precipitated silica which is well suited to use in silicone rubber formulations (RTV-1, RTV-2, HTV and LSR), particularly well suited to use in HTV silicone rubber formulations. It has a BET surface area of 185˜260 m2/g, a CTAB surface area of 100˜160 m2/g, a BET/CTAB ratio of 1.2˜2.6, and a conductivity of <250 μS/cm. Also provided are a process for producing the precipitated silica and the use of the precipitated silica for thickening and reinforcing silicone rubber formulations.

Hydrophilic silica as filler for silicone rubber formulations

The present invention is directed to a process for producing treated filler including (a) treating a slurry of untreated filler which has not been previously dried, with a treating composition including an organosilane material of specified structure (I); and (b) drying the treated filler slurry. The present invention also is directed to treated filler prepared by the process, as well as rubber compounding compositions and tires including the treated filler.

Treated fillers, compositions containing same, and articles prepared therefrom

The invention concerns a novel method for preparing a precipitated silica, wherein: a silicate is reacted with at least one acidifying agent so as to obtain a precipitated silica suspension; the precipitated silica suspension is filtered in order to obtain a filter cake; the filter cake is subjected to a disintegration operation involving the addition of an aluminium compound; following the disintegration operation, a drying step is carried out. The invention is characterized in that, during or after the disintegration operation, methylglutaric acid is added to the filter cake. The invention also concerns novel precipitated silicas and their uses.

Novel method for preparing precipitated silicas, novel precipitated silicas and their uses, in particular for strengthening polymers

The invention relates to a process for the preparation of a novel precipitated silica, wherein: a silicate is reacted with an acidifying agent, so as to obtain a silica suspension; said silica suspension is filtered, so as to obtain a filter cake; said filter cake is subjected to a liquefaction operation, optionally in the presence of an aluminium compound; wherein at least one polycarboxylic acid is added to the filter cake, during or after the liquefaction operation. It also relates to a novel precipitated silica and to its uses.

Process for the preparation of precipitated silicas, precipitated silicas and their uses, in particular for the reinforcement of polymers

The invention concerns a novel method for preparing a precipitated silica, involving the following steps: - reacting a silicate with an acidifying agent in order to obtain a suspension of precipitated silica, - filtering said suspension of precipitated silica, so as to obtain a filtration cake, - subjecting said filtration cake to a spalling operation, - after the spalling operation, carrying out a step of drying, characterised in that at least one polycarboxylic acid is added to the filtration cake during or after the spalling operation. It also concerns novel precipitated silicas and the uses of same.

Novel method for preparing precipitated silicas, novel precipitated silicas and the uses of same, in particular for reinforcing polymers

Carboxylic acids are employed during the preparation of precipitated silica or a suspension of precipitated silica to provide precipitated silicas with low water uptake, which are useful, for example, as reinforcing fillers for silicon matrices.

Preparation of precipitated silicas useful as fillers in silicon matrices

L'invention concerne l'utilisation d'acide carboxylique lors de la preparation de silice precipitee ou de suspension de silice precipitee, les silices precipitees obtenues, en particulier a faible reprise en eau, utilisables notamment comme charge renforcante dans les matrices silicones.

Procede de preparation de silice precipitee, silice precipitee obtenue et utilisations, notamment comme charge dans les matrices silicones

The invention relates to the use of carboxylic acid during the preparation of precipitated silica or a suspension of precipitated silica and to the precipitated silicas thus obtained, particularly with low water uptake, which can be used, for example, as a reinforcing filler in silicon matrices.

Soline Daudey

Papers

Preparation of precipitated silicas useful as fillers in silicon matrices

Procede de preparation de silice precipitee, silice precipitee obtenue et utilisations, notamment comme charge dans les matrices silicones

Method of preparing precipitated silica, precipitated silica thus obtained and use thereof, for example as a filler in silicon matrices