A SOLUBLE AND CONDUCTIVE POLYANILINE COPOLYMER HAVING SYNERGISTIC NIR LIGHT ABSORPTION AND LOWER CRITICAL TEMPERATURE (LCST)

S. BONGIOVANNI ABEL; M.A. MOLINA; C.R. RIVAROLA; C.A. BARBERO

Cancún

Congreso; XXVII INTERNATIONAL MATERIALS RESEARCH CONGRESS; 2018

A linear block copolymer (PNIPAM-b-PANI), containing a thermosensitive block(poly(NâÃÂ?ÂÂ?ÃÂ?ÂÂ?isopropylacrylamide, PNIPAM) and a NIR light absorbing block (polyaniline, PANI), is synthesized. A PNIPAM block terminated in an aniline moiety is first made by radical polymerization of NIPAM using p-aminethiofenol as chain transfer agent. Then, the PANI block is grown the PNIPAM block by oxidative polymerization of aniline. The copolymer is soluble in aqueous and non-aqueous solvents, where PNIPAM is soluble, unlike PANI. Thin films of the copolymer are electrically conductive suggesting that the PANI blocks are electrically connected. Besides, studies using H1-NMR and FT-IR spectroscopies confirm the proposed structure. We propose that the PANIblock act as light-heat transductor, thus after absorbtion of NIR light, the produced heat should triggers the colapse of the PNIPAM block. Indeed, it is shown that the soluble polyaniline aggregate upon NIR light irradiation. The photothermal induced aggregattion occurs in solution, as shown by turbidimetry, and in thin films, as shown by atomic force microscopy. Therefore, PNIPAM-b-PANI could be applied in photothermal therapy, sensors/actuators devices, and in responsive surfaces/coatings.