Poly­(ethylene dioxythiophene):poly­(styrenesulfonate) (PEDOT:PSS) has emerged as a promising candidate for renewable, clean, and reliable energy generation from waste heat due to its thermoelectric properties. This largely stems from its tunable and potentially high electrical conductivity. However, the resulting small Seebeck coefficients diminish the thermoelectric efficiency. We employ dedoping methods making use of acido-base and redox dedoping in order to optimize its properties. In order to tune the charge carrier concentration in PEDOT:PSS thin films, aqueous solutions of readily available inorganic salts, namely, sodium hydrogen carbonate (NaHCO3), sodium sulfite (Na2SO3), and sodium borohydride (NaBH4), are introduced in different concentrations into PEDOT:PSS solutions before thin film fabrication. This yields optimized thermoelectric properties in terms of power factors up to 100 μW/K2 m. Changes in the electronic structure are characterized using UV–vis spectroscopy and XPS, while changes in the conformation are investigated using Raman spectroscopy. The thermoelectric quantities are compared for the redox dedopants regarding the absolute number of reducing equivalents.

Aliphatic polyamides, or nylons, are typically highly crystalline and thermally robust polymers used in high-performance applications. Nylon 6, a high-ceiling-temperature (HCT) polyamide from ε-caprolactam, lacks expedient chemical recyclability, while low-ceiling temperature (LCT) nylon 4 from pyrrolidone exhibits complete chemical recyclability, but it is thermally unstable and not melt-processable. Here, we introduce a hybrid nylon, nylon 4/6, based on a bicyclic lactam composed of both HCT ε-caprolactam and LCT pyrrolidone motifs in a hybridized offspring structure. Hybrid nylon 4/6 overcomes trade-offs in (de)­polymerizability and performance properties of the parent nylons, exhibiting both excellent polymerization and facile depolymerization characteristics. This stereoregular polyamide forms nanocrystalline domains, allowing optical clarity and high thermal stability, however, without displaying a melting transition before decomposition. Of a series of statistical copolymers comprising nylon 4/6 and nylon 4, a 50/50 copolymer achieves the greatest synergy in both reactivity and polymer properties of each homopolymer, offering an amorphous nylon with favorable properties, including optical clarity, a high glass transition temperature, melt processability, and full chemical recyclability.

For potential applications in the biomedical domain, we report a comprehensive roadmap towards structural hierarchy and anisotropy in electrospun fibers based on scattering and diffraction studies.

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Multimaterial thermally drawn fibers are becoming important building blocks in several foreseen applications in surgical probes, protective gears, or medical textiles. Here, the influence of the thermal drawing parameters on the degree of polymer chain orientation, the related thermal shrinkage behavior, and the mechanical properties of the final fibers is investigated via thermo–mechanical testing and small‐ and wide‐angle X‐ray scattering (SAXS and WAXS) analyses. This study on polyetherimide fibers reveals that the drawing stress, which depends on the drawing speed and temperature, controls the thermal shrinkage behavior and mechanical properties. Furthermore, SAXS and WAXS analyses show that the degree of chain orientation increases with drawing stresses below 8 MPa and then saturates, which correlates with the amount of observed shrinkage. The use of this process‐dependent polymer chain alignment to tune the mechanical and shrinkage properties of the fibers is highlighted and controlled bending multimaterial fibers made of two polymethyl methacrylates having different molecular weights are developed. Finally, a heat treatment procedure is proposed to relax the chain alignment and increase the dimensional stability of devices such as temperature sensors. This deeper understanding can serve as a guide for the processing of complex fibers requiring specific mechanical properties or enhanced thermal stability.

Interpreting the polarimetric data from fiber-like macromolecules constitutive of tissue can be difficult due to strong scattering. In this study, we probed the superficial layers of fibrous tissue models (membranes consisting of nanofibers) displaying varying degrees of alignment. To better understand the manifestation of membranes' degree of alignment in polarimetry, we analyzed the spatial variations of the backscattered light's Stokes vectors as a function of the orientation of the probing beam's linear polarization. The degree of linear polarization reflects the uniaxially birefringent behavior of the membranes. The rotational (a-)symmetry of the backscattered light's degree of linear polarization provides a measure of the membranes' degree of alignment.

Electrospinning is a versatile technique to produce nanofibrous membranes with applications in filtration, biosensing, biomedical and tissue engineering. The structural and therefore physical properties of electrospun fibers can be finely...

Template free route for hybrid silica nanoparticles with~500 m 2 .g −1 surface area.• Cocondensation of a nonsilane precursor to achieve phosphonic acid functionality. • Silica nanoparticles displayed highMethylene blue adsorption (380 mg. g −1 ). • This method broaden the precursor selection for mesoporous silica synthesis.