Polymer brush synthesis
Coatings selectively applied to a single side of a mircomechanical cantilever, are the central structural element of a mircomechanical cantilever sensor. Often the coating is only physisorbed, which prohibits the use of the sensor in liquid media. We investigate polymeric brushes on mircomechanical cantilevers as a covalently fixed coating which may not be washed of in a liquid analyte. In the area of gas phase sensing we investigate the differences between different surface binding strategies on sensor response. Current research focuses on a grafting from approach using controlled ATRP and photo-iniferter polymerization techniques as well as grafting to approaches using reactive ester coupling chemistry. The switching behaviour of the polymeric brushes is further investigated with scattering techniques in order to correlate changes in surface stress with changes in the brush layer structure. As a challenge to chemistry, special emphasis is placed on the ability to coat select cantilevers of a micromechanical cantilever array, in order to use the remaining uncoated cantilevers as references. In order to achieve this various structuring approaches such as shadow masks and inkjet printing are used in order to confine the polymerization reaction to specified surface areas.