Sheet silicate lamellae with a high aspect ratio
AssigneeBYK-Chemie GmbH
InventorsHussein Kalo, Josef Breu, Matthias Stoeter, Matthias Daab
Life of this patent
Estimating the term…
Abstract
The present invention relates to sheet silicate lamellae of a 2:1 sheet silicate with a high aspect ratio, to a method for producing these sheet silicate lamellae and to an aqueous dispersion which comprises the sheet silicate lamellae. The present invention further relates to the use of the sheet silicate lamellae of the invention for producing a composite material, and also to a corresponding composite material comprising or obtainable using the sheet silicate lamellae, more particularly for use as a diffusion barrier or as a flame retardant.
Claims12
Sheet silicate lamellae obtainable by delaminating a 2:1 sheet silicate, having ordered interstratification, in water, comprising at least the steps of
- (i) preparing the 2:1 sheet silicate having an ordered interstratification by treating a 2:1 sheet silicate (A) with a solvent mixture of water and a monoalcohol having 1 to 4 carbon atoms that comprises an alkylammonium salt,
- wherein the 2:1 sheet silicate (A) has a Lagaly layer charge of 0.56 p.f.u. to 0.90 p.f.u. and the interlayers at least alternately have sodium cations,
- (ii) separating the 2:1 sheet silicate having an ordered interstratification from the solvent mixture of the alkylammonium salt,
- (iii) delaminating the 2:1 sheet silicate having an ordered interstratification by introducing the 2:1 sheet silicate having an ordered interstratification and separated under (ii) into water to produce an aqueous dispersion comprising sheet silicate lamellae, and
- (iv) separating the sheet silicate lamellae from the dispersion prepared under (iii), wherein
- the sheet silicate lamellae have an average aspect ratio of at least 10 000.
(canceled)
(canceled)
Dependencies are inferred from the claim text.