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Summary: This investigation presents a simultaneous and convenient approach to produce a high‐performance polyimide with a low dielectric constant by introducing the octa‐acrylated polyhedral oligomeric silsesquioxane (methacrylated‐POSS) into a polyimide matrix to form polyimide semi‐interpenetrating polymer network (semi‐IPN) nanocomposites. The differential scanning calorimetry (DSC) and Fourier‐transform infrared (FT‐IR) results indicate that the self‐curing of methacrylated‐POSS and the imidization of polyamic acid (PAA) occurs simultaneously. The morphology of a semi‐IPN structure of polyimide/POSS‐PI/POSS nanocomposites with POSS nanoparticles embedded inside the matrix is elucidated. The POSS particles are uniform and are aggregated to a size of approximately 50–60 nm inside the polyimide matrix. The interconnected POSS particles are observed at high POSS content. The structure is highly cross‐linked, so the PI/POSS nanocomposites have an enhanced glass transition temperature. The high porosity of the PI/POSS nanocomposites markedly reduces the dielectric constant of PI because of the nanometer‐scale porous structure of POSS.

Polyaniline (PANI) is doped with H2SO4, HCl, poly(acrylic acid) (PAA), poly(acrylic acid‐co‐maleic acid) (PAMA), PAA+HCl, and poly(styrenesulfonic acid) (PSS) to obtain PANI‐H2SO4, PANI‐HCl, PANI‐PAA, PANI‐PAMA, PANI‐(PAA+HCl), and PANI‐PSS films, respectively. Ultraviolet‐visible (UV‐Vis) and Fourier transform infrared (FT‐IR) spectroscopy result confirm that PANI is doped with PSS. X‐ray photoelectron spectroscopy (XPS) results indicate that the nitrogen atoms of PANI‐PSS are the most positively charged in these films. Scanning electron microscopy (SEM) images reveal that these films are composed of highly porous nanowires. Platinum (Pt) can be incorporated into PANI‐H2SO4, PANI‐HCl, PANI‐PAA, PANI‐PAMA, PANI‐(PAA+HCl), and PANI‐PSS films via electrochemical deposition to obtain PANI‐H2SO4‐Pt, PANI‐HCl‐Pt, PANI‐PAA‐Pt, PANI‐PAMA‐Pt, PANI‐(PAA+HCl)‐Pt, and PANI‐PSS‐Pt composite electrodes, respectively. Auger electron spectroscopy (AES) results indicate that Pt particles disperse more uniformly into the spatial regions of PANI‐PSS and PANI‐(PAA+HCl) than those of other films. The PANI‐PSS‐Pt electrode provides the most active surface area of Pt in these electrodes. Cyclic voltammetry results and chronoamperometric response measurements show that the activity and stability toward methanol oxidation of the PANI‐PSS‐Pt electrode are the best in these electrodes.

Carbon nanofibers functionalized with aminobenzoyl groups (CNF–aminobenzoyl) were prepared via direct Friedel–Crafts acylation in polyphosphoric acid.