Ionic gels represent a promising electrolyte platform for electrochromic devices owing to their intrinsic ionic conductivity and safety. However, achieving mechanical robustness and interfacial adhesion without sacrificing ionic conductivity remains a significant challenge. In this work, we present a supramolecular-polymer double-network (SP-DN) ionic gel electrolyte, in which a supramolecular network formed through the self-assembly of 1,3:2,4-dibenzylidene sorbitol synergistically interacts with a covalently cross-linked polymer network. The SP-DN ionic gel synergizes superior mechanical strength and robust interfacial adhesion with high ionic conductivity and optical transparency. Electrochromic devices fabricated with this ionic gel electrolyte show rapid switching dynamics, high coloration efficiency, and robust stability over 2000 cycles. Moreover, electrochromic devices fabricated on ITO-poly(ethylene terephthalate) substrates retain 90.6% of their initial optical contrast after 1000 bending cycles, underscoring the potential of the SP-DN ionic gel for flexible applications.

Since their discovery, banded polymer spherulites have remained among the most striking polymer morphologies, exhibiting order over exceptionally large length scales. With the advent of nanoscale structural probes (nano-XRD), their microstructure is now well established: banded spherulites of many polymers were shown to comprise radially growing lamellae that twist continuously. The recent article by E.M. Woo and colleagues-“Pioneering Study on Poly(trimethylene terephthalate) Grating Assembly: Architecture and Formation Mechanism Probed Using X-Ray Microbeam” (Polymer 330 (2025) 128512)- revisits this question using, among other methods, microfocus X-ray scattering. The authors reaffirm a “grating” model in which discontinuous crystal growth of the PTT crystalline lamellae produces periodic, synchronous reorientation of lamellar crystallites. In this note, we show that the spatial resolution of their microfocus experiment is insufficient to support the principal conclusions of that model. Moreover, earlier microfocus studies of PTT with substantially higher spatial resolution, conducted more than a decade ago, demonstrated that banded PTT spherulites consist of radially growing lamellae that twist continuously.

Thermosensitive bottlebrush triblock copolymers combining poly(N-isopropylacrylamide) (PNIPAM) and poly (ethylene glycol) (PEG) represent a promising class of responsive soft materials. We investigate their molecular morphology and gelation behavior using direct-space imaging, synchrotron small-angle X-ray scattering (SAXS), and coarse-grained simulations. Atomic Force Microscopy (AFM) revealed wormlike bottlebrush backbones, while PNIPAM end blocks were detected under specific conditions using modified substrates. Transmission and scanning transmission electron microscopy (TEM/STEM) with negative staining corroborated AFM observations and provided consistent contour-length distributions. Variable-temperature SAXS revealed fully reversible structural reorganization upon heating above the PNIPAM LCST. This transition was marked by the emergence of an ordered gel network, evidenced by an interference peak corresponding to interdomain spacing and formfactor oscillations associated with PNIPAM micelles. Analysis indicated modest micelle growth while the interdomain spacing remained constant. Complementary dissipative particle dynamics simulations reproduced these features and revealed a crossover at phi pol approximate to 0.04, where bridging subchains dominate network formation. Together, these results provide a multiscale understanding of bottlebrush copolymer gelation and identify key parameters controlling their responsive behavior.

Synthesis and characterization of a series of novel graft copolymers based on siloxane backbones containing 50%, 20%, and 10% of laterally attached π-conjugated [1]benzothieno[3,2-b][1]benzothiophene (BTBT) units are presented. The copolymers were synthesized via hydrosilylation reaction of linear poly(methylhydrosiloxanes) of varying functionality with alkenyl-functionalized 2-octyl-7-(undec-10-en-1-yl)-BTBT. Comprehensive investigations by DSC, TGA, and synchrotron SAXS/WAXS revealed that at room temperature all the copolymers synthesized form crystalline phases with layered structures, where both the phase-transition temperatures and the layer thickness strongly depend on the grafting density. As the grafting density decreases, the fraction of crystallizable side chains is reduced, leading to an increase in the amorphous component. Their semiconductor properties were preliminarily elucidated in organic field-effect transistors fabricated via spin-coating, which showed the hole mobilities in the range of 1.6 × 10-4 to 2 × 10-2 cm2V-1s-1 depending on the grafting density of BTBT units to the polysiloxane main chain. These are the first graft copolymers containing BTBT side chains possessing semiconductor properties comparable to those of π-conjugated linear copolymers. These findings establish grafted polysiloxanes as a promising platform for developing solution-processable, high-performance organic semiconductors.

Block copolymers (BCPs) are essential in nanotechnology due to their ability to self-assemble into well-defined nanostructures. In the context of structured liquids, a fundamental understanding of microphase behavior is key to the rational design of advanced soft-matter materials. This study investigates the phase behavior of viscoelastic poly (butadiene)-block-poly (dimethylsiloxane) (PB1,2-b-PDMS) copolymers, where PB segments exhibit 100 % 1,2-microstructure. We focus on how molecular parameters-such as block asymmetry, degree of polymerization, and segregation strength-govern the resulting morphology. In-situ small-angle X-ray scattering was employed to monitor real-time, temperature-dependent order-order and order-disorder transitions (ODT). Copolymers with low molecular weight values exhibited gradual loss of order, while intermediate ones underwent sharp ODT and high molecular weight systems preserved long-range order and structural orientation across wider temperature ranges. In all sequences the morphological behavior was impacted by the PDMS content. These findings provide new insight into the thermotropic self-assembly behavior of low-modulus, nanostructured BCPs and highlight their potential in applications such as soft lithography, flexible electronics, and neurointerfaces.

A photoinduced shape memory effect was demonstrated in nanocomposites consisting of thermoplastic polyurethanes (TPU) and embedded gold nanoparticles (AuNPs). Using a synergistic approach combining confocal micro-Raman spectroscopy and fast scanning chip calorimetry (FSCC), we investigated the localized melting of the TPU crystalline phase, induced by photothermal heating of AuNPs under green laser irradiation. Furthermore, the influence of the nanoparticles on the crystallization behavior and polymorphic transitions of TPU was also examined using structural and thermal analysis techniques. The observed light-triggered thermal response highlights the potential of these nanocomposites for remote, spatially resolved actuation in advanced shape memory and soft robotic systems.

A characteristic correlation peak in small-angle X-ray scattering (SAXS) profiles of brush-like polymers, commonly referred to as the "bottlebrush peak", provides key insights into molecular packing in melts and networks. The peak position, intensity, and width are known to depend on brush architecture and chemical composition. However, a clear understanding of the origin of the peak is still lacking, frequently leading to its assignment to an unrelated structural length scale. To resolve this ambiguity, we conducted a systematic investigation of brush macromolecules spanning comb and bottlebrush regimes using a combination of SAXS, rheology, and coarse-grained molecular dynamics simulations. In densely grafted bottlebrushes, side chains effectively suppress backbone fluctuations, resulting in semiflexible filament-like conformations. In this regime, the peak position q* corresponds to an effective brush diameter d = 2 pi/q*, scaling with grafting density as d similar to n(g)(-1/2), where n(g) corresponds to backbone spacing between side chains. In contrast, comb polymers with lower grafting densities exhibit distinct scaling behavior, depending on chemical composition. For homopolymer combs, where backbones and side chains are chemically identical, the peak shifts to lower q, following q*similar to n(g)(-1/4), reflecting coupled composition fluctuations of the interlinked backbones and side chains. A similar behavior is observed in heteropolymer combs composed of weakly immiscible backbones and side chains. For heteropolymer combs with strongly immiscible components, the peak exhibits a low-q shift, q*similar to n(g)(-alpha) with a scaling exponent 1/4 < alpha <= 2/3. This behavior is a signature of a microphase separation between incompatible backbones and side chains and is associated with a characteristic domain size, L = 2 pi/q*similar to n(g)(alpha). Together, these results identify distinct physical origins of the bottlebrush peak across diverse brush systems.

Thanks to its natural origin, biocompatibility, and relatively simple manufacturing process, gelatin is a widely used gelling agent in the pharmaceutical, cosmetic, and food industries. Traditionally, the main sources of gelatin have been mammalian bones and skin. In recent years, there has been considerable interest in fish-derived raw materials as an alternative source of gelatin. However, the use of fish gelatin is limited by its insufficient viscoelastic properties and mechanical strength, as well as its low thermal stability. In the present work, the enhancement of the viscoelastic behavior of gelatin hydrogels in the presence of the natural polysaccharide κ-carrageenan was examined. We studied the mechanical properties, supramolecular structure, and selected physicochemical characteristics of fish and mammalian gelatin hydrogels combined with κ-carrageenan using rheological measurements, scanning electron microscopy (SEM), small-angle X-ray scattering (SAXS), wide-angle X-ray scattering (WAXS), and contact angle analysis. Our rheological studies revealed substantial changes in the viscoelastic and stress-strain properties of hydrogels based on fish gelatin. The gel melting point of the combined system based on fish gelatin and κ-carrageenan increased from 18 to 44 °C, becoming slightly higher than that of the mammalian gelatin/κ-carrageenan system (42 °C). A much weaker effect of κ-carrageenan was observed on almost all properties of mammalian gelatin than on those of its fish analogue. Thus, κ-carrageenan significantly alters the structure and properties of fish gelatin hydrogels, increasing their gel-sol transition temperature. These results could provide new insights into protein-polysaccharide supramolecular complexes and broaden the technological applications of fish gelatin as an underused protein source.

This review explores the use of staining techniques for polymers in transmission electron microscopy, with a focus on commonly employed staining agents and their mechanisms of interaction with polymeric materials. It offers detailed insights into contrast generation, emphasizing how specific stains selectively enhance electron density in distinct polymer phases to reveal morphological and structural features. Established contrast enhancement methods, such as heavy metal staining with agents like osmium tetroxide and ruthenium tetroxide, are discussed in depth. The review also highlights recent advancements in alternative staining strategies, illustrating emerging trends and expanding possibilities for high-resolution imaging in soft matter characterization.

Thermoplastic polyurethanes (TPUs) based on crystallizable biodegradable polyesters are of significant interest due to their unique mechanical and thermal properties, which depend not only on phase-separated morphology but also on the volume fraction, composition, and local distribution of crystallites in the soft segments. This study investigates the spherulitic structures of multi-block TPUs containing poly (butylene adipate) (PBA) and poly (epsilon-caprolactone) (PCL) diols using synchrotron microfocus X-ray scattering, polarized optical microscopy, and differential scanning calorimetry. The microstructure of melt-crystallized thin films was examined as a function of polymer composition and crystallization temperature. TPU-PBA forms non-banded spherulites exhibiting the metastable beta-phase at 25 degrees C and the stable alpha-phase at 35 degrees C. PCL-based TPU films show non-banded spherulites of PCL crystals regardless of the crystallization temperature. TPU-C, containing both PBA and PCL blocks, produces two distinct spherulite types: banded spherulites of alpha-phase PBA and non-banded spherulites with beta-PBA and PCL crystals. For TPU-B, an equimolar blend of TPU-PBA and TPU-PCL, both banded and non-banded spherulites contain all three crystalline phases. Orientational maps from 2D microfocus X-ray diffraction reveal typical fast radial growth along the a-axis for PBA and the b-axis for PCL in non-banded spherulites. However, in banded spherulites of TPU-C and TPU-B, slow growth occurs along the b-axis for PBA and the a-axis for PCL, indicating a 90 degrees switching of growth directions. This phenomenon is attributed to epitaxial matching between the (100) plane of PCL and the (010) plane of beta-PBA. In non-banded spherulites, beta-PBA and PCL lamellae grow independently with different thicknesses. Conversely, in banded spherulites, the parallel growth of PCL on beta-PBA along the slow direction ensures lamellar thickness matching, minimizing surface free energy. Mechanical stress at the PBA-PCL interface generates banding, inducing a beta-to-alpha solid-state transition and converging the melting peaks of alpha-PBA and PCL.

Conjugated polymers represent promising hole‐transport materials (HTM) used for the fabrication of efficient and stable perovskite solar cells (PSCs). Herein, a novel wide‐bandgap polymer Lira24 is designed based on Si( i ‐Pr) 3 ‐substituted benzodithiophene and bis(2‐ethylhexyloxy)benzene moieties. Alternation of selected building blocks in polymer backbone provides the formation of S∙∙∙O non‐covalent intramolecular interactions, which are beneficial for the planarization of polymer chains, better π‐conjugation and consequently improved charge transport. The developed polymeric HTM show enhanced hole mobility of 1.7×10 −3 cm 2 V −1 s −1 in respect to that of widely used PTAA, and well‐aligned energy of highest occupied molecular orbital (−5.39 eV) with valence band of MAPbI 3 absorber material. As a result, PSCs with Lira24 delivered an encouraging power conversion efficiency of 18.1% remarkably outperforming the efficiency of PTAA‐based control devices. The results of this work illustrate the importance of backbone structure control in the design of hole‐transport materials for efficient perovskite photovoltaics.

Perfluorosulfonic acid ionomer-based membranes are highly effective in hydrogen energy and other applications. However, widely applied Nafion (R) membranes have drawbacks. Developing electrolyte membranes with higher conductivity is a challenge. The research purpose is studying structure and transport properties of a series of Aquivion-type membrane samples, which differ from Nafion (R) membranes by shorter side chains. The samples vary in degree of annealing. It is found that the conductivity of Aquivion membranes in NaCl solutions weakly depends on the annealing degree, whereas the permselectivity for Na+ transport increases with increasing annealing. The Aquivion membranes' conductivity grows with increasing NaCl concentration, C, and at C = 1.5 M reaches 25 mScm-1, which is 2.5 times greater than that of Nafion (R) 117 membrane. The permselectivity at this concentration is 0.99, the same as that of Nafion (R) 117. A simulation based on the microheterogeneous model quantitatively describes the experimental results under the assumptions discussed in the paper.

Conjugated compounds including thiophene and benzothiadiazole units are promising candidates for next-generation semiconductor materials. Precise control over morphology and crystal orientation is critical for optimizing device performance. By employing a combination of synchrotron nano-focus X-ray scattering and fast chip calorimetry, a correlation was established between the size of ordered domains formed during isothermal crystallization and charge carrier mobility. These findings highlight the potential of advanced in situ techniques for fine-tuning the electronic properties of organic semiconductors.

Synchrotron microbeam X-ray diffraction was employed to investigate the local-scale structure and solid-state phase transformation within individual spherulites of poly(vinylidene fluoride) (PVDF). In thin, non-oriented films, PVDF crystallizes into α and γ phases, forming distinct spherulitic morphologies: large, banded α-spherulites and smaller, irregular “mixed” spherulites dominated by the γ-phase. For samples crystallized at high undercooling (160 °C), the mixed spherulites primarily consisted of the γ-phase, with only a minor fraction of α-lamellae localized at the spherulite boundaries. At higher crystallization temperatures (165 °C), the α-phase was entirely absent from the mixed spherulites. High-temperature annealing induced a phase transformation from the α-phase to the γ-phase, initiating at the interface between α- and γ-spherulites. The transformation propagated radially along the b-axis of the α-spherulite, while its characteristic banded morphology remained intact. Radial scanning with an X-ray microbeam provided spatially resolved mapping of the structural transition within the α-spherulite at the micrometer scale, offering detailed insights into the transformation mechanism and its impact on the spherulitic structure. The fast crystal growth direction remained unaltered during the transition, suggesting minimal material transport and maintaining structural coherence.

Achieving simultaneous tissue-mimetic mechanical properties and electrical conductivity within a single molecular system remains a major challenge. Typically, the design of stretchable and flexible electronic materials requires a trade-off between mechanical compliance and electronic performance. Herein, we employ a computationally driven materials design strategy to synthesize polydimethylsiloxane bottlebrush graft copolymers with precisely controlled fractions of poly(3-hexylthiophene) (P3HT), where the grafts serve both as physical cross-links between bottlebrush strands and as conductive elements. Thin films cast from solution reveal percolation of P3HT needle-like crystals, corroborated by transmission electron microscopy, small-angle X-ray scattering, and computer simulations. These films exhibit a distinctive combination of properties, including a low elastic modulus (∼1-100 kPa) and an electrical conductivity of up to ∼10-2 S/cm. Materials that simultaneously combine tissue-like mechanics with electronic functionality hold strong potential for wearable and implantable devices.

Multi-responsive polymeric nanocontainers attract significant attention for their potential applications in biotechnology, drug delivery, catalysis, and other fields. By incorporating a liquid-crystalline (LC) mesogenic ligand with an alkyl tail length ranging from 8-12 carbons, ionically linked to the polymer backbone, we generate vesicles with walls significantly thinner than those of conventional polymersomes, approaching the thickness of a lipid bilayer. These LC vesicles, ranging in size from 50-120 nm, are designed to be mechanically robust due to the alignment of the hydrophilic polymer backbone within the plane of the vesicle wall. Additionally, incorporating a temperature-sensitive block into the polymer structure imparts thermoresponsiveness to the nanocontainers, enhancing their functionality and adaptability for various applications. Ionic complexes of hydrophilic polybases, specifically poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and PDMAEMA-b-PNIPAM (poly(N-isopropylacrylamide)) block copolymers, with amphiphilic wedge-shaped mesogens bearing a sulfonic acid group at the focal point were synthesized. The designed nanocontainers, in the form of either vesicles or nanotubes, exhibit a well-defined wall thickness of 5 nm, dictated by the organization of a smectic LC phase. The constructed coarse-grained models elucidate the mechanism of self-assembly, demonstrating that the balance between the hydrophilicity of the main polymer chain and the hydrophobicity of the wedge-shaped pendant groups determines both the internal and external structure of the vesicles.

Architecturally hindered crystallization of bottlebrush graft copolymers offers a reaction- and solvent-free pathway for creating injectable elastomers with tissue-mimetic softness. Currently, injectable materials involve solvents and chemical reactions, leading to uncontrolled swelling, leaching of unreacted moieties, and side reactions with tissue. To address this issue, bottlebrush copolymers with a poly(ethylene glycol) (PEG) amorphous block and crystallizable poly(lactic acid) (PLA) grafted chains (A-g-B) were synthesized, with grafted chains of controlled length arranged along the backbone at controlled spacing. The densely grafted PEG brush is leveraged to architecturally control both the rate and degree of crystallization of PLA grafts, offering tunability of mechanical properties as a function of architecture and time in a single-component solvent-free system covering a broad range of aggregation states comprising fluid-, paste-, and elastomer-like behaviors with modulus ranging from 1 to 50 kPa. The PLA-g-PEG pastes are particularly interesting, as they combine solvent-free injectability and time-controlled formation of shape-persistent elastomers at constant temperature. This molecular paste platform may advance reconstructive surgery, drug depots, and tissue engineering.

Correction for ‘Elucidating the influence of side chains on the self-assembly of semi-flexible mesogens’ by Raluca I. Gearba et al., Chem. Commun., 2025, https://doi.org/10.1039/d4cc05421k.

Ultra-soft injectable hydrogels are paramount in biomedical applications such as tissue fillers, drug depots, and tissue regeneration scaffolds. Synthetic approaches relying on linear polymers are confronted by the necessity for significant dilution of polymer solutions to reduce chain entanglements. Bottlebrush polymers offer an alternative approach due to suppressed chain overlap and entanglements, which facilitates lower solution viscosities and increased gel softness. Leveraging the bottlebrush architecture in linear-bottlebrush-linear (LBL) block copolymer systems, where L is a thermosensitive linear poly(N-isopropylacrylamide) block, and B is a hydrophilic polyethylene glycol brush block, injectable hydrogels were designed to mimic tissues as soft as the extracellular matrix at high polymer concentrations. Compared to an analogous system with shorter brush side chains, increasing the side chain length enables a decrease in modulus by up to two orders of magnitude within 1–100 Pa at 20 wt% polymer concentrations, near to the physiological water content of ~70%. This system further exhibits thermal hysteresis, enabling stability with inherent body temperature fluctuations. The observed features are ascribed to kinetically hindered network formation by bulky macromolecules.

Organic semiconductor materials are interesting due to their application in various organic electronics devices. [1]benzothieno[3,2-b][1]benzothiophene (BTBT) is a widely used building block for the creation of such materials. In this work, three novel solution-processable regioisomeric derivatives of BTBT—2,7-bis(3-octylthiophene-2-yl)BTBT (1), 2,7-bis(4-octylthiophene-2-yl)BTBT (2), and 2,7-bis(5-octylthiophene-2-yl)BTBT (3)—were synthesized and investigated. Their optoelectronic properties were characterized experimentally by ultraviolet–visible and fluorescence spectroscopy, time-resolved fluorimetry, and cyclic voltammetry and studied theoretically by Time-Dependent Density Functional Theory calculations. Their thermal properties were investigated by a thermogravimetric analysis, differential scanning calorimetry, polarizing optical microscopy, and in situ small-/wide-angle X-ray scattering measurements. It was shown that the introduction of alkyl substituents at different positions (3, 4, or 5) of thiophene moieties attached to a BTBT fragment significantly influences the optoelectronic properties, thermal stability, and phase behavior of the materials. Thin films of each compound were obtained by drop-casting, spin-coating and doctor blade techniques and used as active layers for organic field-effect transistors. All the OFETs exhibited p-channel characteristics under ambient conditions, while compound 3 showed the best electrical performance with a charge carrier mobility up to 1.1 cm2·V−1s−1 and current on/off ratio above 107.