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Structurally dynamic single-chain polymer nanoparticles that can reversibly undergo a coil to particle transition via formation and cleavage of intramolecular dynamic enamine cross-links are reported. [ABSTRACT FROM AUTHOR]

Conducting polymer electrodes based on poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) present many advantages for biological signal recording over traditional metal electrodes and are being steadily evaluated in health monitoring applications. A main requirement for wearable electrodes based on PEDOT:PSS is that selected additives, such as crosslinking agents, avoid the redispersion of the polymer or its postprocess delamination. In this work, a novel approach is presented to fabricate water stable conducting free‐standing films and textile electrodes by using a divinyl sulfone (DVS) crosslinker. As opposed to pristine and glycidoxypropyltrimethoxysilane (GOPS)‐crosslinked formulations, the stability of the conducting PEDOT:PSS/DVS is achieved without reducing its conductivity or an extreme stiffening of its mechanical properties. PEDOT:PSS/DVS formulation is easily processed on any substrate and forms low surface resistance free‐standing or textiles electrodes. Electrochemical and stretchable properties of the PEDOT:PSS/DVS in air and in an aqueous environment are demonstrated and its performance in recordings of electrophysiological signals such as electrocardiography is evaluated. This three‐component material shows great potential for making wearable and humidity stable devices in healthcare applications. Furthermore, it can also be highly attractive for the development of washable electroactive textiles. The use of divinyl sulfone as a crosslinker in the poly(3,4‐ethylenedioxythiophene): poly(styrene sulfonate) allows the fabrication of conformable, highly conductive, stable in water, and stretchable electrodes finding an application in cutaneous electrophysiology and enabling the development of mechanically robust wearable electronic textiles. [ABSTRACT FROM AUTHOR]

Weinvestigate, by means of computer simulations, the formationof soft nanoparticles by irreversible intramolecular cross-linkingof homofunctional polymer precursors in good solvent. Simulationsreveal that the early and intermediate stages of the cross-linkingprocess are dominated by bonding at short contour distances. Becauseof the initial self-avoiding character of the precursor, bonding atlong contour distances, which is the efficient mechanism for globalcompactation, is a rare event that essentially occurs in the latestage of cross-linking. Thus, irreversible cross-linking of precursorswith identical molecular weight and linker fraction produces bothcompact and sparse objects. This is confirmed by a detailed analysisof the size and shape distribution of the fully cross-linked nanoparticles.We also investigate intramolecular cross-linking of heterofunctionalpolymers with two species of orthogonal linkers, bonding between distinctspecies being forbidden. It is found that simultaneous cross-linkingof both species and sequential cross-linking (activation of one speciesafter full cross-linking of the other) lead to the same structuralproperties for the resulting nanoparticles. The heterofunctional nanoparticlesare on average smaller and more spherical than the homofunctionalcounterparts, though still a significant fraction of sparse objectsis found. The simulation results are compared with results from SEC/MALLSand SAXS experiments in real polymeric nanoparticles. [ABSTRACT FROM AUTHOR]