Hydrophilic PET surfaces by aminolysis and glycopolymer brushes chemistry

Abstract : Poly(ethylene terephthalate) (PET) is a semiaromatic thermoplastic polyester used in many fields. For specific applications, controlled of the surface wettability (hydrophily/hydrophoby) could be a great challenge. Aminolysis of PET surfaces with branched polyethylenimine gives amino functional groups on the surface with high grafting density. Then, in a second step, atom transfer radical polymerization (ATRP) initiator was grafted by reaction with 2‐bromoisobutyryl bromide. Surface initiated ATRP of 2‐lactobionamidoethyl methacrylate (LAMA) was performed in solution in the presence of a sacrificial initiator or an appropriate amount of Cu(II) species that act as deactivator. The efficiency of all reactions was confirmed by X‐ray photoelectron spectroscopy. Wetting properties and surface energy were found to vary systematically depending to the type of functionalization and grafting. The quantity of grafted carbohydrate was determined by phenol/sulfuric acid colorimetric titration. The sugar graft density was observed to vary according to the ratio (monomer)/(free initiator). High graft density could be obtained yielding to superhydrophilic polymer brushes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2689–2697