Design of photoresponsive surfaces based on epoxy/isocyanate polymers

MARIA J. GALANTE; ELISABETH PENOFF; LUCÍA VENTURA; PATRICIA OYANGUREN

Mar del Plata

Simposio; XVI Latin-American Polymer Symposium, XIV Iberoamican Polymer Congress; 2018

INTEMA-CONICET-UNMdP

Azobenzene-containing polymers have been extensively investigated because of the unique response of the azobenzene moiety to light fields. Its key feature is the efficient and reversible isomerization between a thermally stable trans-state and a metastable cis-state. On the other hand, the incorporation of fluorine into polymers has been extensively explored because of the unique characteristics of fluorine substitution. The introduction of trifluoromethyl groups into polymers improves chemical resistance, surface, electrical, mechanical, and optical properties of the polymers compared to the non fluorinated materials.In this work, we focus on the influence of surface dipole moment on the photoswitchable wettability of azobenzene-modified surfaces, as a result of irradiation with light of an appropriate wavelength. Photosensitive azobenzene molecules undergo reversible trans-cis isomerization, causing large changes in the molecular geometry as a result of UV/visible irradiation. To investigate this behavior in more detail, epoxy/isocyanate based polymers containing azobenzene groups with and without fluorine were synthesized, characterized, and compared their photoresponse.