No abstract

We present the preparation of advanced antistatic and anticorrosion coatings of polystyrene (PS) incorporating a suitable amount of dodecylbenzenesulfonic acid (DBSA)‐doped SiO2@polyaniline (SP) core–shell microspheres. First, aniline‐anchored SiO2 (AS) microspheres that were about 850 nm in diameter were synthesized using the conventional base‐catalyzed sol–gel process with tetraethyl orthosilicate in the presence of N‐[3‐(trimethoxysilyl)propyl]aniline. SP core–shell microspheres were then synthesized by chemical oxidative polymerization of aniline monomers with ammonium persulfate as an oxidizing agent in the presence of the AS microspheres. The polyaniline shell thickness of the as‐prepared core–shell microspheres was estimated to be about 120 nm. The AS and SP microspheres were further characterized using Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy. The as‐synthesized DBSA‐doped SP core–shell microspheres were then blended into PS using N‐methyl‐2‐pyrrolidone as solvent and then cast onto a cold–rolled steel (CRS) electrode to obtain antistatic and anticorrosion coatings with a thickness of about 10 µm. The corrosion protection efficiency of the as‐prepared coating materials on the CRS electrode was investigated using a series of systematic electrochemical measurements under saline conditions. The enhanced corrosion protection ability of the PS/SP composite coatings may be attributed to the formation of a dense passive metal oxide layer induced by the redox catalytic effect of the polyaniline shell of the as‐synthesized core–shell microspheres, as evidenced by electron spectroscopy for chemical analysis and SEM observations. Moreover, the PS composite coating containing 10 wt% of the SP core–shell microspheres showed an electrical resistance of about 3.65 × 109Ω cm−2, which meets the requirements for antistatic applications. Copyright © 2012 Society of Chemical Industry

In this paper, we present the first preparation of an intrinsically dopable polyimide (DPI) membrane containing an amine-capped aniline trimer (ACAT) that reveals advanced gas separation capabilities as well as mechanically and thermally enhanced properties. The as-prepared DPI membrane was synthesized by reacting ACAT and 4,4 0 -(4,4 0isopropylidenediphenoxy)bis(phthalic anhydride) (BSAA) through a conventional thermal imidization reaction. Polyaniline (PANI) and conventional nondopable polyimide (NDPI) membranes were also prepared as controls. The DPI membranes were found to reveal permselectivities (R) of O 2 /N 2 of about 13.54, which is about 1.96-and 1.54-fold higher than that of NDPI and PANI, respectively, based on the investigation of gas permeability analysis (GPA). Upon doping with 1.0 M HCl (aq), the pemselectivities of DPI for O 2 /N 2 were found to be further increased to about 16.63. Moreover, significantly enhanced mechanical and thermal properties of the as-prepared DPI membrane were also found as compared to those of NDPI and PANI membranes, based on the studies of dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA), respectively.

No abstract

An electroactive polyimide fiber (EPF) mat based on conjugated segments of electroactive aminocapped aniline trimer (ACAT) as a diamine and 4,4 0 -(4,4 0 -sopropylidenediphenoxy)-bis(phthalic anhydride) (BSAA) as a dianhydride was successfully prepared by electro-spin technology with electrochemical activity and dopable properties, which were similar to polyaniline. The degree of electrochemical activity and dopable properties can be tuned by varying the content of ACAT existing in the as-prepared electro-spun EPF mats. After doping with perfluorooctanesulfonic acid (PFOS), the water contact angle of EPF surface is increased from hydrophobicity at 133 to superhydrophobicity at 155 . It is interesting that the EPF mat undergoes a switchable process from superhydrophobicity to superhydrophilicity via doping with PFOS and de-doping with ammonium gas.