Search

By applying the electrocapillary rise wetting, ECRW, with varied voltages and solvents to wet lignin and polyacrylonitrile, PAN, respectively, this work proven that this method can in situ enhance the surface free energy and polarity of polymers. Results showed that the voltage increase can in situ enhance the adsorption of only polar solvent by polymer to lead the reduction of related contact angle because of the adsorption of non-polar solvent by polymer ignoring the voltage variety. The diiodomethane was greatly adsorbed by both lignin and PAN due to the surface free energy of these polymers dominated by the non-polar Lifshitz-van der Waals interaction component. The voltage increase would enhance the Lewis acid-base interaction component of polymer to cause the enhancement of the surface free energy and polarity of polymers. This work showed that the polymer structure corresponding to the Lewis base may have different electric responses because the voltage increase has been found to cause the Lewis base component enhancement for ring structure-based polymer, e.g. lignin, and reduction for isotacticity structure-based polymer, e.g. PAN.

Several polyaniline, PANI, nanofibers, with controlled morphology and chiroptical properties were fabricated by using two developed unusual interfacial syntheses, UIS. Taking the l - and d -camphorsulfonic acid, CSA, as guiders, the first developed UIS is to prepare the bi-phase volumes in asymmetrical by setting the top phase volume/bottom phase volume, TPV/BPV, at 1/2 and 2/1 (vol%), respectively. The second developed UIS is to vary the diameter, Φ, of interfacial area at bigger, e.g. 71 mm, or smaller e.g. 52 mm, respectively. FESEM images showed that the reduction of the TPV and the increase of the interfacial area both would reduce the diameter of l / d -CSA doped PANI nanofibers. CD spectra showed that the reduction of the TPV and the increase of the interfacial area both would enhance the chiroptical properties of PANI nanofibers.

A new electric method was introduced for reducing graphene oxide, GO. Experimentally, an electrostatic generator was employed to provide varied voltages together with the control of the electrostatic force, EF, in enhancement or reduction, respectively. Results showed that the Raman intensity ratio of D/G bands, ID/IG, for reduced GO, rGO, was increased with the voltage increase, especially under the EF-enhancement condition, and this condition formed rGO also showed flaky structure with the larger size as compared with the EF-reduction formed samples.

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.