Polymerization of aniline hydrochloride in reverse of microemulsion by batch and semicontinuous process using ionic and nonionic surfactants

Abstract

The polymerization of aniline hydrochloride by inverse microemulsion in a batch process and the semicontinuous process was studied as a function of the surfactant ionic and nonionic. Polymerizations were carried out at 60°C for 4 h with a yield polymer of circa 67 and 27% wt. for ionic and nonionic surfactants. The conductivity of synthesized polyaniline by the semicontinuous process is higher up to three orders of magnitude than that of the batch process for both surfactants. The calculating degree of oxidation by UV-Vis showed the relative intensities of the quinoid to benzenoid unit around one. The morphology was determined by Scanning Electron Microscopy (SEM) and observed that the formation of the different morphologies is due to the self-assembly behavior of surfactant. The diameter z-average particle size (Dz) was studied by Transmission Electron Microscopy (TEM), which determined that the diameter particle in a semicontinuous state is larger than the one produced in a batch; this is due to the control of monomer addition in the system. These findings suggest that the polymerization process and the type of surfactant influence the properties of polyaniline.

Sensor performance and computational study of polyaniline film in ethylenediamine detection

“…As shown in Figure 3, the absorbance intensity at 748 nm decreased during dedoping process whereby the ES is expected to be converted into insulating leucoemeraldine (LE) after EDA immersion. On the other hand, the absorbance intensity at 748 nm increased during redoping process as expected at which LE was converted back to ES when doped with HCl 17 . Since the conversion between ES and LE is a reversible mechanism, it can be easily obtained by applying the dedoping or redoping process.…”

“…One dedoping process (A) by using EDA with 7 s response time and one redoping process (B) with 5 s recovery time with 3 M of HCl are considered as one cycle. It is expected that the ES will be converted to insulating LE after EDA immersion, whereas LE will be converted back to ES when redoped with 3 M HCl 17 . According to Figure 7, the shift of the data is within a narrow range (0.088–0.171) and the baseline is relatively horizontal.…”

“…It is expected that the ES will be converted to insulating LE after EDA immersion, whereas LE will be converted back to ES when redoped with 3 M HCl. 17 According to Figure 7, the shift of the data is within a narrow range (0.088-0.171) and the baseline is relatively horizontal. Overall, PAni(0 C) shows good reusability of up to 10 cycles with short response time and recovery time of 7 and 5 s, respectively.…”

“…On the other hand, the absorbance intensity at 748 nm increased during redoping process as expected at which LE was converted back to ES when doped with HCl. 17 Since the conversion between ES and LE is a reversible mechanism, it can be easily obtained by applying the dedoping or redoping process. The π to polaron transition at 732-748 nm is selected to study the absorption shift of PAni sensor before and after EDA immersion as it is the most significant absorption shift among the three characteristic peaks of PAni.…”

“…The decrease in I Q/B ratio shows that PAni backbone possesses predominant benzenoid moieties which has demonstrated the conversion of ES to LE. 17 This is because predominating benzenoid units can be found in LE, whereas predominating quinoid units can be found in pernigraniline base (PB). The ratio of benzenoid to quinoid ring in ES is 1:1, while benzenoid ring is the predominant unit in LE.…”