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Electric-assisted capillary rise adsorption of polar and nonpolar solvents by cellulose and chitosan was studied by employing an electrostatic generator to assist a common capillary rise wetting by taking the anode and cathode electrodes respectively linked to a metal tube charged with samples and the probe solvent. To vary the voltage at 0, 100, 200, and 300 V, respectively, the recorded dynamic adsorption results showed that the cellulose and chitosan both kept a stable adsorption of the nonpolar hexane and diiodomethane, obviously ignoring the voltage increase. Moreover, the hexane amount adsorbed by cellulose and chitosan is similar, while the diiodomethane amount was adsorbed to a greater amount by cellulose as compared with the chitosan corresponding to these two biomaterials-based nonpolar components, for example, greater for cellulose and smaller for chitosan. Results also showed that the adsorption of polar water and formamide was gradually increased with the voltage increase, especially for chitosan, to correspond to the polar component of these materials, for example, greater for chitosan and smaller for cellulose. These adsorption behaviors suggested that the application of an extra electric field can only enhance the adsorption of polar solvent, and the molecular structure, for exmaple, the β-(1-4)-linked d-glucosamine units of chitosan, has sensitive electric field responses in polar solvent adsorption as compared with those of the β(1-4)-linked d-glucose units of cellulose. The reason for the electric adsorption behaviors was known due to the presence of an extra electric-field-induced reduction of the total surface tension of solvent and mainly the polar component.

Porous poly(L-lactide), PLLA, and poly(D-lactide), PDLA, films were fabricated by the electric breath figure (EBF) method. The pore sizes of both the PLLA and PDLA films were reduced with the increase in electric voltage; however, the former followed a non-linear fit, whereas the latter followed a linear fit. Under 0 V condition, the average diameter, da, was 15.0 ± 0.50 μm for the PLLA film and 6.66 ± 0.54 μm for the PDLA film, whereas under 3 kV condition, da was 1.65 ± 0.35 μm for the PLLA film and 0.73 ± 0.07 μm for the PDLA film. FTIR spectra analysis showed that the EBF process did not change the structure of PLLA or PDLA.

Polyaniline (PANI) microfibers were prepared by an unusual interfacial synthesis method. Experimentally, the ANI formed aqueous phase (AP) was placed at the top, and the poly( l -lactide) (PLLA) formed oil phase (OP) was placed at the bottom, while the volume of these two phases was varied by taking the ratio of AP/OP at 2/1 and 1/2, respectively. FESEM images showed that the phase volume variety-based two synthesis processes both can form rectangular PANI microfibers while a comparison found that the AP/OP at 2/1 formed microfibers with smaller diameter and longer length than that of the AP/OP at 1/2 formed samples. This suggested that the increase of the AP volume would benefit the interfacial polymerized PANI with better size.

In this work, tea polyphenol (TP) was employed as an environmentally friendly and highly efficient dopant and thermal stabilizer for polyaniline (PANI). Results from UV, XRD, conductivity, TG and solubility studies indicated that the TP was efficient doped in PANI. To compare with the pure PANI, the TP-doped PANI presented enhanced conductivity, thermal stability and solubility due to the TP doped in PANI chains enhanced the π–π* interaction and facilitated the electron delocalization.