WATER REPELLENT ELEMENT AND A METHOD FOR PRODUCING A HYDROPHOBIC COATING

摘要

The invention relates to producing coatings, in particular polymer coatings for rendering hydrophobic rough, porous highly-developed and other substrate having a geometrically complex-shaped surface using supercritical carbon dioxide and is industrially applicable for forming ultrahydrophobic or ultralyophobic coatings on imperfect surfaces. The aim of said invention is to obtain an ultrahydrophobic surface and to increase the water wetting angle of said surface to =130° by precipitating a thin and homogeneous polymer coating from a solution of polymer or copolymer in supercritical carbon dioxide on a rough substrate. The inventive method consists in placing the substrate (3) and a weighting portion of polymer or copolymer in a reactor (2), in sealing said reactor, in filling the reactor (2) with gas CO₂ from a bottle (7), in placing in a thermostatic oven (1) and in setting the required temperature and pressure with the aid of the thermostatic oven (1) and a pressure generator (8) in such a way that the CO₂ is transited into the critical state thereof and said polymer or copolymer is dissolved in the supercritical CO₂. The polymer or copolymer being deposited on the substrate (3), it undergoes the transition into the ultrahydrophobised state (becomes modified). Afterwards, the reactor (2) is decompressed, dismounted and the modified substrate is extracted.