Self-assembly and crystallization in a supramolecular hairy rod polymer from the complex of polyaniline with ω-methoxy poly(ethylene oxide) phosphates

A semirigid conjugated polyaniline (PANI) was complexed with a omega-methoxy poly(ethylene oxide) phosphate (PEOPA) through ionic bonding to yield a supramolecular hairy rod polymer comprised of an ionic PANI backbone and nonionic PEO side chains. The strong backbone-side chain repulsion resulted in a microphase-separated lamellar morphology consisting of alternating ionic and nonionic layers irrespective of the binding fraction. The thickness of the PEO layer increased with increasing binding fraction due to the smaller interfacial area per PEO chain at higher binding fraction which resulted in its higher stretching normal to the lamellar interface. The complex exhibited an order-disorder transition near 225 degreesC driven by deprotonation. The conformational rigidity of PANI backbone coupled with the strong backbone-side chain bonding strongly retarded the crystallization kinetics and the crystallizability of the PEO side chains in the complexes.