METHOD FOR OBTAINING MINERAL POWDER OF HIGH LAMELLARITY AND APPLICATIONS IN PARTICULAR FOR REINFORCING PLASTIC MATERIALS

摘要

The invention relates to a process for treating a lamella-type mineral in the form of particles constituted of stacks of sheets, in order to obtain a functional filler for a polymer material. The process is characterized by the fact that the mineral is suspended in a liquid with a predetermined initial particle size, after which the suspension is subjected to a delamination procedure in order to separate the sheet from the particles, and obtain a particle size smaller than the initial particle size. Said suspension is then subjected to selection in order to eliminate the particles larger in size than the predetermined size; it is subsequently dried, and the mineral particles are treated so as to restrict the creation amongst them of strong irreversible bonds. The talcum powder obtained can be incorporated into a thermoplastic material as a functional filler in order to increase the flexural modulus in proportions significantly higher than what is obtained with known fillers, without diminishing the shock resistance of the final material (with respect to the values obtained with said known fillers).