Soft Matter最新文献

{"title":"Contact formation and viscoelastic detachment in non-circular soft adhesive contacts.","authors":"Sonu Dhiman, Debashish Das","doi":"10.1039/d6sm00791k","DOIUrl":"10.1039/d6sm00791k","url":null,"abstract":"<p><p>Adhesive contact measurements on soft polymers are commonly interpreted using Johnson-Kendall-Roberts (JKR) theory, which is formulated for circular contacts. Non-circular contacts generally require more complex elliptical-contact descriptions, making it unclear when a scalar measure of contact size is sufficient. Here, we examine contact formation and detachment in non-circular soft adhesive contacts using PDMS crossed-cylinder experiments. The cylinder crossing angle was varied from 30° to 90°, producing contacts ranging from highly elongated ellipses to nearly circular geometries while keeping the material pair fixed. During loading, the contact aspect ratio <i>b</i>/<i>a</i> initially evolved but rapidly approached an angle-dependent plateau, indicating approximately self-similar growth. This motivates, but does not by itself prove, an area-equivalent representation based on the radius together with the geometric-mean curvature radius . With these substitutions, the loading branches follow a JKR-type linearization and yield a nearly angle- and preload-independent loading work of adhesion, <i>W</i>_load = 24 ± 1 mJ m^-2. Comparable values obtained from Johnson-Greenwood elliptical-contact fits provide independent support that this result is not an artifact of neglecting ellipticity at the level of the global <i>c</i>(<i>P</i>) response. In contrast, unloading and pull-off are strongly history dependent. The unloading branches can still be represented by an effective JKR-like relation using <i>c</i>, but only with a substantially larger effective separation energy, <i>W</i>_unload,eff, which increases with preload and with decreasing crossing angle. A reduced viscoelastic model based on the same area-equivalent description rationalizes the delayed contact recession and the principal unloading response over 50°-80° at the tested displacement rate. These results show that contact formation in elliptical soft adhesive contacts is governed primarily by area-equivalent scaling, whereas detachment is governed by geometry- and history-dependent dissipative separation. The framework provides a practical route for analyzing non-circular soft contacts using simple global measures while retaining the essential distinction between contact formation and viscoelastic detachment.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":"6710-6726"},"PeriodicalIF":2.9,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149078938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inducing asymmetric lamellar morphology in cylinder-forming block copolymer films using an extractable ionic liquid.","authors":"Kshitij Sharma, Sumair Raul, Akhtar Gul, Nihad Ahmadli, Guangcui Yuan, Sushil K Satija, John F Ankner, Alamgir Karim","doi":"10.1039/d6sm00326e","DOIUrl":"10.1039/d6sm00326e","url":null,"abstract":"<p><p>The morphology of block copolymers (BCPs) is dictated by the relative volume fractions of the constituent blocks. Thus, in an equilibrated state, BCPs exhibit lamellar and non-lamellar structures, such as rods and spheres, for symmetric and asymmetric chain lengths, respectively. Transforming a cylinder-forming BCP with an inherent asymmetric composition into its equivalent asymmetric lamellar morphology is a challenging proposition, but could enable unique applications, such as harmonic frequency selective waveguides. Herein, we transform such an intrinsic PMMA cylinder forming PS-<i>b</i>-PMMA thin film system into its equivalent asymmetric lamellar structure, using the PMMA-philic ionic liquid (IL) EMIM-TFSI. We observed that the system formed nano-micelles consisting of a spherical PS core block and a PMMA/IL corona, upon casting films from a PMMA selective solvent, acetone. The IL migrates to the PMMA domains due to a combination of the preferential solvent and the high cohesive energy density (CED) of the IL promoting connectivity of the corona phase. Subsequent vacuum annealing of the films at elevated temperature (10 h at 180 °C) extracts the IL, lowering the CED barrier and allowing for progressive coalescence of the nano-micelles into continuous thin PS and PMMA layers, thus producing substrate parallel asymmetric PS-<i>b</i>-PMMA lamellae as confirmed by neutron reflectometry and surface island and hole formation phenomena. Stabilized by the substrate and air interfacial wetting interactions, these PS-<i>b</i>-PMMA lamellae with asymmetric composition in a deep meta-stable state, maintain their film structure with elevated temperature vacuum thermal annealing. This simple strategy has potential to be universally applied to dial-in alternate non-equilibrium morphologies for many pristine BCP systems, in defiance of thermodynamically controlled equilibrium morphologies, making them attractive for many nanotechnology applications, from membranes to photonic crystals.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":"6689-6701"},"PeriodicalIF":2.9,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149101262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polypeptide complex coacervate core micelles as model nanoreactors for mild synthesis of gold nanoparticles.","authors":"Brendan Karafinski, Zihan Zhang, Nairiti Sinha","doi":"10.1039/d6sm00664g","DOIUrl":"https://doi.org/10.1039/d6sm00664g","url":null,"abstract":"<p><p>Complex coacervate core micelles (C3Ms) assembled from cationic poly(D,L-lysine) (PRK, R is racemic) and poly(L-glutamate)-<i>b</i>-poly(ethylene glycol) (PLE-<i>b</i>-PEG) are investigated as preassembled, biomimetic nanoreactors for the mild synthesis of gold nanoparticles (AuNPs). Systematic comparison across coacervate architectures (AB + C, A + BC, AB + BC, and bulk A + C) demonstrates that the presence of a polymer-rich coacervate phase results in AuNP formation, with the PEG corona playing a dual role as both a microphase-separation driver and a steric stabilizer. Small-angle X-ray scattering (SAXS) experiments indicate that only architectures producing a well-defined dense coacervate core support AuNP formation, and that nanoreactor morphology is preserved during the early nucleation and growth periods. Time-resolved UV-visible light absorption spectroscopy, dynamic light scattering, and SAXS collectively allude to a kinetic framework consistent with the classical LaMer mechanism. These results establish polypeptide C3Ms as simple nanoreactors for mild metal/metal oxide nanoparticle synthesis.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supramolecular aggregate packing transitions as a strategy for molecular discrimination.","authors":"Xiao Yang, Feiyu Li, Xifang He, Yanan Yang, Lingbo Ji, Dahui Zhao, Baojiang He","doi":"10.1039/d6sm00723f","DOIUrl":"https://doi.org/10.1039/d6sm00723f","url":null,"abstract":"<p><p>Inspired by the conformational rearrangements of G-protein-coupled receptors (GPCRs) during signal transduction in the human olfactory system, this study proposes and validates a molecular discrimination strategy based on packing mode transitions of organic supramolecular aggregates. We constructed four supramolecular aggregates using naphthalene diimide (NDI) derivatives as core building blocks. These aggregates enabled the discrimination of aliphatic amines, aromatic amines, and structurally similar alkaloids, including nicotine and cotinine. Our results demonstrate that subtle differences in molecular structure can induce a reduction in internal packing density and molecular order within the aggregates, and these packing changes are transduced as shifts in spectroscopic signals and variations in spectral intensity. Molecular dynamics simulations further reveal that steric hindrance and electrostatic interactions play key roles in modulating the packing modes of the aggregates, providing molecular-level support for the experimental observations. This work validates the feasibility of using structural responses of supramolecular aggregates for molecular discrimination and offers new experimental and theoretical perspectives on the structural behavior of organic aggregates upon chemical perturbation.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Operational envelopes for designing with soft actuators using a simplified continuum approach.","authors":"Zach Miller, Saman Jamshididana, Nicolas Gonsalves, Ben Holmgren, Sameh Tawfick, John Parmigiani, Devin Roach","doi":"10.1039/d6sm00757k","DOIUrl":"https://doi.org/10.1039/d6sm00757k","url":null,"abstract":"<p><p>Liquid crystalline elastomers (LCEs) are soft materials capable of large, reversible deformations in response to external stimuli, making them promising alternatives to rigid actuators where compliance and untethered motion are crucial. However, adoption of LCEs in real-world systems has been hindered by the lack of practical modeling techniques that describe their functional behavior. Here, we present an analytical continuum framework based on decomposition of the actuation and elastic strains. Paired with existing hyperelastic models, this decomposition yields closed-form constitutive expressions which describe LCE behavior over a broad range of operating conditions. We experimentally validate the framework by showing it successfully predicts the stress state of an LCE across a variety of actuation sequences with low bias and error, indicating path independence for processes where elasticity dominates behavior. We further demonstrate the framework's flexibility by applying it to LCE fibers of different chemistry, and to a fiber having a complex hierarchical architecture; a capability crucial to employing LCE actuators in practical systems. Finally, we illustrate the utility of the resulting closed-form solutions through two design applications: quantitatively determining the coefficient of friction for a low-friction material, and a qualitative procedure for designing an LCE-actuated bistable mechanism. This work provides designers and researchers in soft robotics, microactuators, and compliant systems with a practical, rapidly deployable framework for characterizing and comparing thermoactive soft actuators.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rheology and programmable gelation of DNA tadpoles.","authors":"Jennifer Harnett, Saminathan Ramakrishnan, Elizabeth P Holmes, Alice L B Pyne, Davide Michieletto","doi":"10.1039/d6sm00371k","DOIUrl":"10.1039/d6sm00371k","url":null,"abstract":"<p><p>DNA origami is a powerful method to achieve nanoscale folded structures. DNA origami is typically employed to create precisely and tightly folded objects often in small quantities and studied at single molecule scale. Here, we use the DNA origami method to design and fold polymers with complex topologies, and study their rheology and viscoelastic properties in dense conditions. First, we designed and purified topologically distinct DNA nanostructures - linear, circular, and \"tadpole\" polymers - to evaluate how polymer architecture influences entanglement and rheology. Despite their distinct topologies, we observe that all constructs obeyed universal rheological scalings, likely due to their short length. However, upon thermal annealing in the bulk, the DNA polymers displayed significantly different behaviours. Our results suggest that DNA polymers could be used to engineer thermoresponsive behaviours in complex fluids by introducing reversible and topology-dependent crosslinking.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13662780/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of constitutional isomerism on molecular ordering and thermal shifts.","authors":"D Sandhya Kumari, D Megha, B Venugopal, G Shanker","doi":"10.1039/d6sm00628k","DOIUrl":"https://doi.org/10.1039/d6sm00628k","url":null,"abstract":"<p><p>We introduce naphthol-cholesteryl dimers showing that constitutional isomerism in a rigid core dictates mesophase structure and thermal stability. Planar naphthalene-diol cores linked to a chiral cholesteryl segment <i>via</i> flexible spacers permit subtle substitution changes that switch packing from V-shaped branches to linear rods, sharply altering the mesophase type and transition temperatures. Linear <i>para</i>-isomers promote tight π-π stacking, elevating average clearing temperatures (<i>T</i>_C) above 177 °C and broadening the nematic phase range. In contrast, V-shaped variants lower <i>T</i>_C to an average of 135 °C. XRD shows intercalated SmA layers, and UV-vis reveals concentration-dependent H-aggregation in the 2,6-series. Both dimers exhibit monomer/excimer fluorescence; 2,6-NCh-Dn shows enhanced solid-state emission and larger Stokes shifts-a difference that highlights aromatic geometry as a key template when designing mesogens.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sublattice-selective acoustic attenuation <i>via</i> a band-index-conserved flat channel in a Lieb-patterned ferromagnetic nematic liquid-crystal array.","authors":"Dongwook Lee, Jiwon Seo","doi":"10.1039/d6sm00521g","DOIUrl":"https://doi.org/10.1039/d6sm00521g","url":null,"abstract":"<p><p>A Lieb lattice of ferromagnetic nematic liquid-crystal elements yields a sublattice-programmable acoustic response, switched on or off by the drive geometry rather than enhanced attenuation. The central result is a point-group-protected drive-selection rule: at the Brillouin-zone center, the B/C-antisymmetric drive projects entirely onto the B₁ irrep of the <i>C</i>_4v little co-group while the uniform and A-only drives contain no B₁ component, so the corresponding drive overlaps <i>η</i>_flat = 1, 0, 0 are exact symmetry consequences, independent of the range of the intersite coupling. Two independent features of the Lieb sublattice structure enable the wider construction. First, the bipartite chiral symmetry pins a zero-eigenvalue mode whose eigenvector has vanishing amplitude on the corner sublattice, making the associated collective channel insensitive to uniform corner-sublattice detuning. Second, when the on-site frequencies and couplings are sublattice-symmetric, the Lieb band index is conserved and the flat magnetic channel hybridizes only with the flat acoustic channel, so the acoustic loss feature at the single-site frequency <i>ω</i>_<i>m</i>(<i>H</i>) is sourced by the flat-channel overlap of the driving field. An interdigitated transducer with oppositely biased combs on the B- and C-edge sublattices maximizes this overlap at Γ and gives the largest Brillouin-zone-averaged overlap among the drive geometries considered; a uniform drive suppresses it. We quantify the selection by an integrated contrast _sel ≈ 10. We further show that a direct B-C hopping generated by dipolar coupling lifts the flat band and reduces the global band-index-conservation selection rule away from Γ, but does not compromise the <i>C</i>_4v-protected drive gating at Γ; realizing the stronger full-Brillouin-zone flat-channel calibration would require engineered short-range interactions that reduce the effective B-C coupling, and an elastic/anchoring contribution is one possible, but presently unverified, route. The Lieb geometry selects a symmetry-filtered acoustic function distinct from the broad, integrated response of frustrated hexagonal flat-band lattices.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multivalent adhesion of flexible nanocarriers to cell membranes: effects of architecture, subdivision, and length.","authors":"Saba Mirahsani, Morteza Hamzeh, Fatemeh Ahmadpoor, Samaneh Farokhirad","doi":"10.1039/d6sm00753h","DOIUrl":"https://doi.org/10.1039/d6sm00753h","url":null,"abstract":"<p><p>Multivalent adhesion between ligand-functionalized nanocarriers and cell-surface receptors underlies targeted drug delivery, yet how the structure of flexible carriers regulates binding independently of stiffness remains poorly understood. We use a multiscale statistical mechanics-based framework coupling a deformable-membrane continuum model to coarse-grained models of flexible nanocarriers, ligands, and receptors. Monte Carlo simulations quantify multivalency and resolve binding free energies into enthalpic and entropic contributions. We compare star and linear architectures, subdivision of a fixed ligand budget among multiple carriers, and contour lengths across receptor densities and membrane excess areas. Bond number is receptor-limited at low receptor density and ligand-limited at high density, yielding similar multivalency among designs. Carrier structure instead controls the organization and thermodynamic quality of comparable bond populations through enthalpy-entropy compensation, with receptor translational entropy as the dominant penalty. Linear nanocarriers bind more favorably than star nanocarriers at matched stiffness and multivalency because they incur a smaller collective configurational penalty. Ligand-budget subdivision produces a nonmonotonic response: at high receptor density, the single-carrier system is most favorable and the two-carrier system least favorable because of entropic penalties and weaker receptor-ligand enthalpic stabilization. Contour length produces a weaker receptor-density-dependent crossover: shorter carriers are favored at low receptor density, longer carriers at intermediate density, and their binding free energies converge after ligand saturation. Membrane excess area modulates these balances without imposing a universal ordering. Similar bond numbers can therefore conceal substantial differences in adhesion free energy, providing design principles for matching carrier structure and ligand organization to receptor expression and membrane mechanics.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149178054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-sustained GaIn droplet oscillations by coupled electrochemical and mechanical driving forces.","authors":"Yi Li, David Paulovics, Mathieu Odijk, Javier Rodríguez Rodríguez, Ivana Qianqi Lin, Detlef Lohse, Christian A Nijhuis","doi":"10.1039/d6sm00708b","DOIUrl":"10.1039/d6sm00708b","url":null,"abstract":"<p><p>Self-sustained oscillations of liquid-metal droplets represent a striking example of electrochemical-mechanical coupling in active matter. These liquid-metal droplets immersed in an aqueous solution oscillate toward and away from an electrode, in response to a continuous applied voltage. Recently, these oscillations have been studied in gallium-indium (GaIn) droplets. Though it is understood that the GaIn droplet self-oscillations are driven by surface tension variations, the details of the underlying mechanism remain incompletely understood, in part because previous investigations have relied primarily on optical observations. Here, we introduce an experimental platform that enables simultaneous electrochemical and optical characterization of self-oscillating GaIn droplets in an aqueous NaOH electrolyte under wet-electrochemical conditions in both an unconfined and laterally confined (Hele-Shaw) geometry. By correlating the time dependence of the current with the droplet dynamics, we could identify five distinct stages in the oscillation cycle, involving (i) droplet-electrode contact and positive charging, (ii) droplet spreading due to oxide growth, (iii) droplet detachment and asymmetrical contraction, (iv) inertial movement away from the electrode, and (v) electrowetting-driven return to the electrode. The measurements reveal two sequential driving mechanisms, namely asymmetrical contraction-induced inertial movement (following oxide dissolution) and an electrowetting-induced Marangoni flow associated with charge redistribution at the liquid-metal/electrolyte interface. Furthermore, we observe reversal of the interfacial flow direction and transient decoupling of surface and bulk motion. These findings provide new insight into the electrochemical-mechanical driving mechanism governing liquid-metal droplet oscillators in aqueous solutions.</p>","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13656080/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149163378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}