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Despite decades of research, the fundamental question of structure and morphology of the poly(3,‐4‐ethylenedioxythiophene):poly(styrene sulfonate) complex (PEDT: PSS) electrically conducting polymer remains open. Here, through a systematic study of the polymerization of 3,4‐ethylenedioxythiophene (EDT) on two series of sulfonated polystyrenes, i.e., PS‐co‐SSH and PS‐co‐SSNa, with per cent sulfonation 24 ≲ x ≲ 100, this study shows that the substrate polyelectrolyte not only affords charge compensation and processability, but also templates the morphology of the growing PEDT chain—whether extended, coiled or collapsed. This determines the electrical, electronic and optical properties of the resultant PEDT: PSS interpolyelectrolyte complexes, including their work function. This study calls this the Polyelectrolyte Template model. The PEDT: PSS complex retains memory of its polymerization morphology even after subsequent ion‐exchange, for example, to the same acid form. Electrical conductivity decreases sharply with decreasing x, and depends on whether the polymerization is templated with the H+ or Na+ form of the polyelectrolyte. The work function is less sensitive to x, but exhibits a transition from low to high work function (5.2–5.3 eV) when x exceeds a threshold, which indicates formation of a polar surface driven by molecular‐scale segregation of the PSS counteranion. This surface segregation also affects the ability of these complexes to inject holes into very large‐ionization‐energy semiconductors. [ABSTRACT FROM AUTHOR]

We describe six aqueous formulations prepared from anionic HYPAN, an acrylic acid/acrylamide copolymer, and cationic poly(diallyldimethylammonium chloride) (PDADMAC) for stabilization of loamy sandy soil and quartz sand. The formulations were deposited on the surface of soil and sand that after drying resulted in the formation of protective polymer–soil and polymer–sand coatings. Most formulations gave mechanically stable coatings with a strength of 100–200 kg cm−2 and sustained a storm wind of 76 km h−1. A non‐stoichiometric HYPAN–PDADMAC polycomplex with a 10‐fold excess of anionic HYPAN units formed the water resistant coatings, which retained 99% soil and 90% sand. These characteristics were superior to those for coatings made from a conventional binder polyacrylamide. Additionally, the coating from soil and 'anionic' non‐stoichiometric interpolyelectrolyte complex increased the total amount of stored water and lengthened the time of water release. Anionic polymer formulations did not exhibit antimicrobial action against bacteria and yeast in both solutions and films. Cationic polymer formulations manifested strong antimicrobial action against bacteria and yeast in solutions, and suppressed the growth of Gram‐positive bacteria and yeast in films. Taking into account the commercial availability of the initial polymers and a simple procedure for polycomplex preparation, there is great potential for anionic polymer formulations as anti‐erosion binders and soil conditioners. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Interpolymer complexes (IPC) Eudragit® EPO/S100 were prepared in different media (water pH of 7.0 and ethanol). According to the elemental analysis, FTIR spectroscopy, and thermal analysis data, IPC prepared in aqueous media (denoted as interpolyelectrolyte complexes—IPECs) is stabilized predominantly by ionic intermacromolecular bonds and has a composition close to equimolar. However, polycomplexes formed in nonaqueous (ethanol) media (denoted as IPC) are stabilized by both hydrogen and ionic bonds and characterized by an almost twofold excess of Eudragit® S100. All samples do not include free copolymer domains. IPECs and IPCs have different behavior in the buffer media mimicking the gastrointestinal tract. Matrices of IPECs are characterized by the surface erosion and pH‐independent swelling profiles with low values of a swelling degree. Matrices of the IPCs swell significantly in the buffer media with pH 1.2, 5.8, and 6.8 with subsequent decrease in the swelling degree due to the surface erosion. According to the assessment of release of the model active pharmaceutical ingredient (API), IPECs are prospective carriers for sustained delivery of II class Biopharmaceutical Classification System (BCS) drug (diclofenac sodium). At the same time, IPCs provide sustained release of the II class BCS and prolonged release of the I class BCS drug (theophylline). [ABSTRACT FROM AUTHOR]

Carbopol polymers are polymers of acrylic acid and crosslinking agents; there is the prospect of penetration of linear macromolecules between the mesh size of crosslinked Carbopol microgels for a certain period of time. Interpolyelectrolyte complex (IPEC) samples between Carbopol and linear polycations (Eudragit EPO—EPO) were obtained at different interpolyelectrolyte reaction (IPER) times (1, 3, and 7 days). Confirmation of the IPEC structures was proved by FTIR and mDSC. Moreover, according to the results of elemental analysis and mDSC, an increase in the duration of IPER time did not lead to a significant increase in the fraction of the incorporated EPO (CS), since its amount in polycomplex samples remains almost unchanged and the Tgs varies slightly and it depends from the Carbopol grade used. Analysis of the particle size and zeta potential of polycomplex gels showed that the obtained IPEC samples are nanosized, and the particle charge depends on the presence of free ionized carboxyl groups Carbopol (Noveon) or positively charged dimethylamino groups of EPO on their surfaces. After increasing the duration of IPER up to 3 days, a decrease in zeta potential values was observed. In the case of 7 days, an increase in particle size was observed due to their aggregation (C2020/EPO, C10/EPO, NAA‐1/EPO). Mathematical modeling of diclofenac sodium release according to the Korsmeyer–Peppas equation showed that all IPEC samples were characterized by the Super Case‐II transport mechanism, except for C10/EPO sample, which was characterized by Anomalous transport. [ABSTRACT FROM AUTHOR]

This mini-review reports on complex macromolecular architectures (interpolyelectrolyte complexes) based on star-shaped polyelectrolytes. These complexes can be prepared in aqueous media via electrostatically driven co-assembly of star-shaped polyions (a) with oppositely charged linear homopolyelectrolytes or (b) with oppositely charged double hydrophilic (ionic/non-ionic) diblock copolymers. In case (a), the complexes can be water-soluble if the charge of the star-shaped macromolecule is only partially compensated by a linear polyion. In case (b), the complexes retain their solubility in aqueous media even under a full charge compensation of the polymeric components. In both cases, the complex macromolecular architectures based on star-shaped polyelectrolytes are characterized by a distinct compartmentalized structure of a micellar ('core-corona') type with an insoluble core, which is assembled from coupled monomer units of the oppositely charged polymeric components, and a hydrophilic, either ionic or non-ionic, corona. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]