Conducting Composites of Polyurethane Resin and Polypyrrole: Solvent‐Free Preparation, Electrical, and Mechanical Properties

Abstract

Three methods were used for solvent-free preparation of conducting composites of PUR and PPy. In all cases, PUR was prepared from TDI and hydroxol 15-W as polyol cross-linker, whereas PPy was obtained upon oxidative coupling of Py using ferric chloride as oxidant. In method 1, PPy powder was dispersed in hydroxol. After addition of TDI the mixture was cured to yield the final product. In method 2, ferric chloride and Py were dissolved in hydroxol and a PPy dispersion was obtained. Then TDI was added and the final product was obtained upon curing. In method 3, Py was dissolved in TDI and ferric chloride dissolved in hydroxol. Then the two solutions were mixed and cured resulting in the simultaneous formation of PPy and PUR. Method 1 led to composites with a specific electrical conductivity s of 10 À10 S Á cm À1 and a Shore A hardness of 40 to 55. Using methods 2 and 3, composites with s values of 10 À7 S Á cm À1 and a hardness of 30 to 40 were obtained. Presence of moisture increased the s values and decreased the hardness. Due to the solvent-free preparation, the maximum PPy content of the samples was limited to 10 wt.-%. The studies also demonstrated that the conductivity was mainly dependent on the amount of ferric chloride present in the sample and not on the PPy content, suggesting that the conductivity was ionic.Flow diagram of different preparation methods for PUR-PPy composites.

A chemically polymerized electrically conducting composite of polypyrrole nanoparticles and polyurethane for tissue engineering

“…Perhaps not surprisingly, others have investigated PPy‐enhanced elastomers in other biomedical applications 24. Although there have been several attempts to synthesize PPy–PU composites,25, 26 the authors know of no relevant studies that characterize such composites for use in TE with SMs. The hybrid material was polymerized using an in situ polymerization emulsion technique.…”

Synthesis and characterization of polypyrrole rod doped with p‐toluenesulfonic acid via micelle formation

“…[3][4][5] Such nanomaterials are applicable in various electronic devices, such as conducting films, obtained by solvent casting; polymer electrodes, obtained by blending; and conducting fillers of electromagnetic shielding materials. [6][7][8][9][10][11] In these applications, conducting particles must exhibit dispersion stability over long periods, and maintain their electrical conductivity. The patterning of conducting polymer circuits by lithography or mold compressing methods has been studied.…”

Conductive Composites of Polyurethane Resins and Ionic Liquids

“…Up to the present, the antistatic equipment of plastics was mainly based on solid additives like technical carbon (carbon black) 3, 4. Some attempts to use graphite,5 silver‐coated inorganic fillers,6 or conducting polymers such as polypyrrole7–10 as additives were recently reported. Low melting additives or additives which are liquid at the processing temperature such as tetraalkylammonium salts, cationic, or non‐ionic surfactants were only occasionally used.…”