In situ preparation and resistance performance of waterborne sulfonate polyurethanes/polypyrrole conductive materials

A series of waterborne sulfonate polyurethanes dispersions(SWPU) was prepared through prepolymerization method by reacting polyethylene glycol(PEG1000) and isophorone diisocyanate(IPDI) with 2,4-diamino-benzene sulfonic acid sodium salt(DASS) as chain extender.Then FeCl3 was employed as oxidant,therefore SWPU/polypyrrole(SWPU/PPy) conductive composite was prepared by in situ chemical oxidative polymerization of pyrrole(Py) in SWPU dispersions.The effects of different preparative conditions including feeding ratios,feeding sequences and reaction conditions on the conductivity of SWPU/PPy conductive composite were studied.Fourier infrared spectra demonstrated the presence of hydrogen-bonding interactions between SWPU and PPy.Results also showed that SWPU/PPy resistivity can achieve 1Ω·cm,when feeding sequence: SWPU→Py→FeCl3,Py concentration was 30%,reaction temperature was 0℃,reaction time was 3h and n(FeCl3) /n(Py)=2.2.