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Biobased hyperbranched poly(ester amide) (HBPEA)/polyaniline (PAni) nanofiber nanocomposites were prepared by incorporating the as-synthesized PAni nanofiber at varied weight percentages by an ex situ polymerization technique. Fourier transform infrared spectroscopic analyses indicated the interactions of the benzenoid–quinoid moieties of PAni with HBPEA. The transition from liquidlike to solidlike behavior of the nanocomposites with a percolation threshold at 10 wt % nanofiber content was studied using dynamic rheology. The formation of nanofibrous network within the HBPEA matrix as vouched for by TEM study and initial degradation temperature (from 277 to 307 °C) was found to be increased with the increment of nanofiber content. The evaluation of mechanical properties such as tensile strength (7.2–12.25 MPa), elongation at break (88–70%), impact resistance (>100 cm), and scratch hardness (8.5–10 kg) together with the decrease in the sheet resistance (from 107 to 105 Ω/sq) forwarded the epoxy–poly(amido amine) cured nanocomposites as prospective antistatic materials.

In the present work, we report a low cost and scalable oil-water interfacial polymerization method to synthesize one-dimensional (1-D) highly conducting polypyrrole (PPy) nanofibers doped with p-toluenesulfonic (p-TSA) and hydrochloric (HCl) acids. Polymerization of pyrrole (monomer) has been carried out at the interface formed between the immiscible oil and aqueous water droplets under constant magnetic stirring at room temperature. Formation of smaller diameter (16-20 nm) PPy nanofibers has been confirmed from the high resolution transmission electron microscopy (HRTEM) studies, and the average diameter of p-TSA doped PPy nanofibers is found to be smaller than that of HCl doped nanofibers. The polymer chain ordering or crystallinity of both p-TSA and HCl doped PPy nanofibers have been studied with X-ray diffraction (XRD). Studies of Fourier transform infrared (FTIR) spectra suggest the presence of all the characteristic vibration bands in doped PPy nanofibers. The doping of PPy nanofibers has been confirmed from the formation of polaron and bipolaron bands in their UV-vis spectra. The optical band gap energy (E) and Urbach energy (E) for PPy nanofibers doped with p-TSA and HCl doped PPy nanofibers were determined from their UV-vis absorption spectra. The red shift of the polaron absorption band in p-TSA doped PPy nanofibers confirms a higher conjugation length of the polymer nanofiber chains than that in the HCl doped PPy nanofibers. Thermogravimetric (TGA) and derivative plots of TGA studies predict that PPy nanofibers doped with p-TSA are thermally and structurally more stable as compared to HCl doped PPy nanofibers. Current-voltage (I-V) characteristics exhibit nonlinear behavior with voltage in both p-TSA and HCl doped PPy nanofibers.

A facile method of ultrasound-assisted noncovalent functionalization of multiwalled carbon nanotubes (MWCNT) with fatty amide of castor oil and use of the same as a reactive component in the in situ polymerization of hyperbranched poly(ester amide) (HBPEA) via an A 2 + B 2 + A′A 2 approach is reported. The reaction entails anchoring of the amide groups to MWCNT to maximize the reaction with the diacids, resulting in formation of the nanocomposite. Fourier transform infrared analyses validated the anchorage of esteramide groups to the nanotubes. Intercalation and formation of dense polymer layers on the isotropically dispersed nanotubes (with mean coherency coefficient of 0.229) were evident from transmission electron microscopy. The changes in biophysico attributes were reflected in their selective efficacy against the Gram-positive bacteria with an enhanced cytotoxicity (death rate increase of Staphylococcus aureus by 137.5% and Bacillus subtilis by 107.6%) and significant decrease in the sheet resistance by 3 orders of magnitude (from 10 7 to 10 4 Ω sq −1 ) as compared to the pristine HBPEA at low loading of 1 wt % MWCNT. The multifunctional nanocomposites maintained the acceptable mechanical performance, and kinetics evaluation of activation energy revealed enhanced thermal stability over pristine HBPEA; the nanocomposites can be envisaged for MWCNT-based bionano applications, particularly in the field of advanced textiles.