Abstract

BURILLO, Guillermina; DIAZ, Andrea  and  BUCIO, Emilio. Characterization of thermo and pH sensitivity of binary graft copolymers onto polytetrafluoroethylene. J. Mex. Chem. Soc [online]. 2006, vol.50, n.1, pp.1-4. ISSN 1870-249X.

The temperature sensitivity (low critical solution temperature LCST), and pH sensitivity of binary grafting of two monomers N-isopropylacrylamide NIPAAm (temperature responsive) and acrylic acid AAc (pH responsive) onto poly(tetrafluoroethylene) PTFE, was studied for the graft copolymers with different grafting percentages, the reversibility of the phase transition from hydrophilic to hydrophobic behavior with change in temperature and pH were also studied. Poly(NIPAAm) has a low critical solution temperature of about 33 °C, but in case of the binary grafting the LCST shift to the lower temperature; probably due to the formation of hydrogen bonds between dimethylamino and acrylic acid groups.

Keywords : LCST; binary grafting; intelligent polymers; PTFE.

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