Polyurethane-based conducting polymer blends: I. Effect of chain extender

Polyurethane (PU) with (m-phenylene 4-diaminosulfonic acid: PDSA) as chain extender can deeply influence the properties of its blending with n-dodecyl benzene sulfonic acid (DBSA) doped polyaniline (PADB) The sulfonic chain extender (PDSA) provides an additional probability of creating H-bonding with PADB molecules which can be characterized by IR-spectra. In the presence of intermolecular H-bonding, the conductivity and tensile strength of the PADB/PU blends can be changed, especially when the conducting PADB forms a continuous phase in the matrix at high PADB composition. Thermal analysis also reveals variation of glass transition points of the blends at various composition due to the interaction and different degree of miscibility. Scanning electronic microscopy (SEM) pictures of the blends demonstrate a more deformed type of morphology when PDBA is used as a chain extender in the preparation of PU.