Partially sulfonated ethylene-vinyl alcohol copolymer as new substrate for 3,4-ethylenedioxythiophene vapor phase polymerization

A new conducting composite polymer film is obtained by vapor phase polymerization of 3,4-ethylenedioxythiophene (EDOT) on a biocompatible polyanion derived from the partial sulfonation (32%) of statistical ethylene vinyl alcohol copolymer (EVAL32). EVALS32 and the oxidant (iron(III) p-toluenesulfonate, [PTS]) are contemporaneously spin coated from a methanol/water solution on glass slide. EVALS32-PTS-coated glass slides are exposed to EDOT vapors, and the polymerization is followed by Vis-NIR spectroscopy. We observed that PEDOT slowly grows into the bulk of EVALS32 matrix. Thanks to the sulfonic groups of the polyanion acting as doping agents, a highly conjugate p-doped EVALS32-PEDOT composite film with a good conductivity (1.6 × 102 S cm-1), transparency, and stability in water is obtained. The EVALS32-PEDOT film seems an ideal candidate for the preparation of organic devices to be applied in electronics, biosensor, or actuation technology. © 2014 Wiley Periodicals, Inc

Wet Adhesion of Buckypaper Produced from Oxidized Multiwalled Carbon Nanotubes on Soft Animal Tissue

Buckypaper (BP) is the general definition of a macroscopic assembly of entangled carbon nanotubes. In this paper, a new property of a BP film produced from oxidized multiwalled carbon nanotubes was investigated. In particular, BP shows to be able to promptly and strongly adhere to animal internal soft and wet tissues, as evaluated by peeling and shear tests. BP adhesion strength is higher than that recorded for a commercial prosthetic fabric (sealed to the tissue by fibrin glue) and comparable with that of other reported optimized nanopatterned surfaces. In order to give an interpretation of the observed behavior, the BP composition, morphology, porosity, water wettability, and mechanical properties were analyzed by AFM, X-ray photoelectron spectroscopy, wicking tests, contact angle, and stress–strain measurements. Although further investigations are needed to assess the biocompatibility and safety of the BP film used in this work, the obtained results pave the way for a possible future use of buckypaper as adhesive tape in abdominal prosthetic surgery. This would allow the substitution of conventional sealants or the reduction in the use of perforating fixation

Wet adhesion of buckypaper produced from oxidized multi-wall carbon nanotubes on soft animal tissue

Buckypaper (BP) is the general definition of a macroscopic assembly of entangled carbon nanotubes. In this paper a new property of a BP film produced from oxidized multi-wall carbon nanotubes was investigated. In particular, BP shows to be able to promptly and strongly adhere to animal internal soft and wet tissues, as evaluated by peeling and shear tests. BP adhesion strength is higher than that recorded for a commercial prosthetic fabric (sealed to the tissue by fibrin glue) and comparable with that of other reported optimized nano-patterned surfaces. In order to give an interpretation of the observed behavior, the BP composition, morphology, porosity, water wettability and mechanical properties were analyzed by AFM, Xray photoelectron spectroscopy, wicking tests, contact angle and stress-strain measurements. Although further investigations are needed to assess the biocompatibility and safety of the BP film used in this work, the obtained results pave the way for a possible future use of buckypaper as adhesive tape in abdominal prosthetic surgery. This would allow the substitution of conventional sealants or the reduction in the use of perforating fixation