| abstract |
A composite material is characterised by a substrate based on vegetable materials, in particular vegetable fibres, vegetable fibre raw materials or vegetable fibre semifinished products, and by a nanocomposite in functional contact therewith obtained by surface modification of (a) colloidal inorganic particles with (b) one or several silanes of the general formula (I): Rx-Si-A4-x, in which the radicals A are the same or different and represent hydroxyl groups or hydrolytically splittable groups, except for methoxy, the radicals R are the same or different and represent non hydrolytically splittable groups and x equals 0, 1, 2 or 3, x≥1 in at least 50 % by volume of the silanes, in the conditions of a sol-gel process with a substoichiometric amount of water, in relation to the available hydrolysable groups, so as to form a nanocomposite sol. If required, the nanocomposite sol is further hydrolysed and condensed before being brought into contact with the substrate and then hardened. |