| 摘要 |
<p>Silicate coatings are produced on surfaces, esp. metals, by coating the surface with a thin layer of a polysiloxane, and converting the polysiloxane layer into a silicate layer bonded to the surface by heating under oxidising conditions. Used for forming a chemically resistant glassy surface on metal apparatus, such as reactor and esp. Golay columns for gas chromatography. The catalytic action of the metal surface is inactivated, while its valuable mechanical properties are maintained. The polysiloxane is pref. dimethylpolysiloxane, phenylmethylpolysiloxane, or cyanoethylpolysiloxane. Heating takes place at a maximum temp. of 300 degrees C, and oxidn. is effected by use of air. The silicate treated surface is silylated by treatment with hexamethyldisilazane, or dimethylchlorosilane.</p> |
