Process for the preparation of a hydrophobic aerogel.

摘要

For an improved hydrophobic aerogel, it is proposed that a correspondingly hydrophobic alkoxy silane mixture be hydrolysed in a basically catalysed manner under the action of ultrasound and the wet gel obtained be dried supercritically. Aerogels thus obtained have an impedance of about 10<5>kg/m<2>s, which corresponds to the optimum value of the impedance matching layer of an ultrasonic transducer.