Design of photoresponsive surfaces based on epoxy/isocyanate polymers

L. VENTURA; M.E. PENOFF; M.J. GALANTE; P.A. OYANGUREN

Mar del Plata

Simposio; XVI Simposio Latinoamericano de Polímeros, XIV Congreso Iberoamericano de Polímeros; 2018

Azobenzene-containing polymers have beenextensively investigated because of the uniqueresponse of the azobenzene moiety to light fields. Itskey feature is the efficient and reversible isomerizationbetween a thermally stable trans-state and ametastable cis-state [1]. On the other hand, theincorporation of fluorine into polymers has beenextensively explored because of the uniquecharacteristics of fluorine substitution. Theintroduction of trifluoromethyl groups into polymersimproves chemical resistance, surface, electrical,mechanical, and optical properties of the polymerscompared to the non fluorinated materials [2].In this work, we focus on the influence of surfacedipole moment on the photoswitchable wettability ofazobenzene-modified surfaces, as a result of irradiationwith light of an appropriate wavelength. Photosensitiveazobenzene molecules undergo reversible trans-cisisomerization, causing large changes in the moleculargeometry as a result of UV/visible irradiation. Toinvestigate this behavior in more detail,epoxy/isocyanate based polymers containingazobenzene groups with and without fluorine weresynthesized, characterized, and compared theirphotoresponse.