Synthesis and characterization of poly(n-undecyl isocyanate)/polyaniline polyblend

Poly(n-undecyl isocyanate) (PUDIC)/n-dodecylbenzenesulfonic acid (DBSA)-doped polyaniline (PANIDBSA) polyblend was prepared and the effect of the H-bonding between these two polymers on the compatibility, conjugation chain length of PANIDBSA, and helixity of PUDIC in the polyblend system were studied. The monomer and polymer were characterized by NMR spectra and the polyblend was analyzed by FTIR, UV-vis spectra, and wide-angle X-ray diffraction. It was found when the blend composition of the PUDIC was higher than 10%, the WAXD patterns demonstrated lower angle shifting for the peaks at around 2θ = 2-2.5°, referring to the distance between the layers of the layered structure of PANIDBSA crystalline with increasing PUDIC, indicating the expansion of the layered structure of PANIDBSA. The FTIR spectra illustrated the presence of an absorption peak at 1700 cm⁻¹ shift to higher wave number with PUDIC due to its H-bonding with PANIDBSA. The UV-vis spectra of PANIDBSA described a blue-shift of the λmax with PUDIC, indicating that the presence of PUDIC in the polyblend system can interrupt and decrease the conjugation chain length of PANIDBSA. The optical activity of the helical PUDIC decreased notably with the presence of PANIDBSA, resulting from the reversed helical effect (de-nature) of H-bonding.