Byk-chemie Gmbh

Matthias Daab

Josef Breu

Hussein Kalo

Andreas Edenharter

Matthias Stoeter

Hubert Schiessling

The invention relates to a process for delamination of a layered silicate in an aqueous medium, wherein in a first step a layered silicate is treated with a delamination agent, and in a second step the thus treated layered silicate is contacted with an aqueous medium, whereby the delamination agent is a compound having exactly one positively charged atom, the positively charged atom being selected from the group consisting of nitrogen and phosphorous; contains nfunctional groups selected from the group consisting of hydroxyl groups, ether groups, sulfonic acid ester groups and carboxylic acid ester groups, nbeing a number from 3 to 10; comprises a total number of carbon atoms nbeing from 4 to 12; has a ratio n/(1+n) from 1 to 2, wherein nis the total number of carbon atoms of the delamination agent and nis the total number of functional groups in the delamination agent as defined under ii.; contains natoms selected from the group consisting of carbon, nitrogen, phosphorous, oxygen and sulfur, nbeing ≥9; and wherein the delamination agent is used to treat the layered silicate in an amount of at least equal to the cation exchange capacity of the layered silicate. The invention further relates to the thus produced delaminated layered silicates, their use in the production of composite and coating material and as a barrier material. Moreover, the invention relates to compositions containing the thus produced delaminated layered silicates.

Process for delamination of layered silicates

A process for delamination of a layered silicate in an aqueous medium includes treating a synthetic or naturally occurring 2:1 clay mineral layered silicate with a delamination agent, and contacting the treated layered silicate with an aqueous medium. An amount of the delamination agent used to treat the layered silicate can be at least equal to the cation exchange capacity of the layered silicate. A delaminated layered silicate can be obtained from the process and provided in a dispersion, a composite, or a barrier.

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.

Growing community of inventors

Bayreuth, Germany

Matthias Daab