Asymmetry in Polymer–Solvent Interactions Yields Complex Thermoresponsive Behavior

ACS Macro Letters, Год журнала: 2024, Номер 13(7), С. 818 - 825

Опубликована: Июнь 14, 2024

We introduce a lattice framework that incorporates elements of Flory–Huggins solution theory and the q-state Potts model to study phase behavior polymer solutions single-chain conformational characteristics. Without empirically introducing temperature-dependent interaction parameters, standard describes systems are either homogeneous across temperatures or exhibit upper critical temperatures. The proposed Flory–Huggins–Potts extends these capabilities by predicting lower temperatures, miscibility loops, hourglass-shaped spinodal curves. particularly show including orientation-dependent interactions, specifically between monomer segments solvent particles, is alone sufficient observe such behavior. Signatures emergent found in Monte Carlo simulations, which display heating- cooling-induced coil–globule transitions linked energy fluctuations. also capably range experimental systems. Importantly, contrast many prior theoretical approaches, does not employ any temperature- composition-dependent parameters. This work provides new insights regarding microscopic physics underpin complex thermoresponsive polymers.

Язык: Английский

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Chemical Compatibilization, Macro-, and Microphase Separation of Heteroassociative Polymers

Macromolecules, Год журнала: 2023, Номер 56(16), С. 6527 - 6542

Опубликована: Июль 31, 2023

A mean-field equilibrium theory for reversible network formation due to heterotypic pairwise interactions in mixtures of associative polymers is extended via a weak inhomogeneity expansion account spatial fluctuations chemical incompatibility. We consider solutions and blends types B with many associating groups per chain, only A–B association between these groups. The structural correlations the reversibly bonded are accounted by considering Gaussian 4-arm star-like chain conformations cross-links, which analogous an affine-network assumption. Future extensions this could further incorporate strand stretching from swelling or strong segregation. show that incompatibility drives competition segregative phase separation. addition cross-links incompatible chains compatibilizes mixture, minimizing propensity macroscopic separation into A- B-rich phases. Under binding segregation conditions, results eutectic-like behavior local microphase crossovers microscopic occur at isotropic Lifshitz points, resulting potential bicontinuous microemulsions. reactive blending such multifunctional presents opportunity envision novel properties, processing applications accessible tunable production supramolecular complexes, mesophases, multicomponent polymer networks.

Язык: Английский

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Sol–Gel Transition in Heteroassociative RNA-Protein Solutions: A Quantitative Comparison of Coarse-Grained Simulations and the Semenov–Rubinstein Theory

Macromolecules, Год журнала: 2025, Номер unknown

Опубликована: Март 5, 2025

Protein RNA-binding domains selectively interact with specific RNA sites, a key interaction that determines the emergent cooperative behaviors in RNA-protein mixtures. Through molecular dynamics simulations, we investigate impact of binding interactions on phase transitions an exemplary system and compare it predictions Semenov–Rubinstein theory associative polymers. Our findings reveal sol–gel (percolation) transition without separation, characterized by double-reentrant behavior as or protein concentration increases. We highlight crucial role bridge formations driving these transitions, particularly when sites are saturated. The quantitatively predicts numbers at equilibrium semidilute regime, but significantly overestimates size range where percolation is observed. This can partly be traced back to fact mean-field assumption not valid dilute regime neglects existence cycles connectivity graph percolating cluster transition. study enriches understanding behaviors, providing valuable insights for interpretation experimental observations.

Язык: Английский

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Interaction networks within biomolecular condensates feature topological cliques near the interface

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2025, Номер unknown

Опубликована: Март 27, 2025

Biomolecular condensates are typically maintained by networks of molecular interactions, with canonical examples including those formed prion-like low complexity domains (LCDs) proteins. Single-component LCD have been predicted to exhibit small-world network topologies and spatial inhomogeneities in protein compaction. Here, we systematically characterize underlying investigate the relationship between single molecule properties topologies. We employ a chemically specific coarse-grained model probe generalize our findings varying sequence hydrophobicity via generic that describes "hydrophobic-polar" (HP) polymers. For both systems, find sustained featuring "hubs" "cliques". Molecular hubs high betweenness centrality localize near centers adopt more elongated conformations. In contrast, cliques-densely interacting molecules form locally fully connected subgraphs-are bridged tend condensate interface. Interestingly, power-law relationships structure dynamics individual centrality, which connectivity. Thus, work demonstrates connectivity can be from single-molecule properties. Furthermore, cliques longer lifetimes their constituent remain spatially constrained, suggesting role shaping interface material

Язык: Английский

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Water vapor absorption of Polyvinyl Butyral (PVB) interlayer for laminated glass

Construction and Building Materials, Год журнала: 2025, Номер 478, С. 141325 - 141325

Опубликована: Апрель 21, 2025

Язык: Английский

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Hydrogels Based on Polyelectrolyte Complexes: Underlying Principles and Biomedical Applications

Biomacromolecules, Год журнала: 2024, Номер unknown

Опубликована: Ноя. 18, 2024

Ionic complexes of electrostatically charged biomacromolecules are key players in various biological processes like nucleotide transportation, organelle formation, and protein folding. These complexes, abundant systems, contribute to the function, responsiveness, mechanical properties organisms. Coherent with these natural phenomena, hydrogels formed through complexation oppositely polymers exhibit unique attributes, such as rapid self-assembly, hierarchical microstructures, tunable properties, protective encapsulation. Consequently, polyelectrolyte complex (PEC) have garnered considerable interest, emerging an up-and-coming platform for biomedical applications. This review outlines underlying principles governing PEC hydrogels. The classification polyelectrolytes self-assembly discussed, including factors influencing their process. Recent developments applications, drug delivery, tissue engineering, wound healing management, wearable sensors, summarized. concludes prospective directions next generation hydrogel research.

Язык: Английский

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Adsorption of Semiflexible Wormlike Polymers to a Bar and their Double-Chain Complex Formation

Soft Matter, Год журнала: 2024, Номер 20(22), С. 4366 - 4388

Опубликована: Янв. 1, 2024

The quantitative transfer matrix approach and scaling arguments in terms of trains, loops, tails supertrains allowed us to characterize the main regimes semiflexible chain adsorption on a bar double-chain complex formation.

Язык: Английский

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Nonuniversal Dynamics of Hyperbranched Metallo-Supramolecular Polymer Networks by the Spontaneous Formation of Nanoparticles

ACS Nano, Год журнала: 2024, Номер 18(42), С. 29282 - 29293

Опубликована: Окт. 14, 2024

Various transient and permanent bonds are commonly combined in increasingly complex hierarchical structures to achieve biomimetic functions, along with high mechanical properties. However, there is a traditional trade-off between strength biological functions like self-healing. To fill this gap, we develop metallo-supramolecular polymer hydrogel based on the hyperbranched poly(ethylene imine) (PEI) backbone phenanthroline ligands, which have unexpectedly plateau modulus at low concentrations. Rheological measurements demonstrate nonuniversal metal-ion-specific dynamics, significantly larger moduli, longer relaxation times, stronger temperature dependencies, compared equivalent networks model-type telechelic precursors, cannot be explained by theory of linear viscoelasticity. TEM images reveal

Язык: Английский

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Theory of the center-of-mass diffusion and viscosity of microstructured and variable sequence copolymer liquids

Soft Matter, Год журнала: 2023, Номер 19(45), С. 8893 - 8910

Опубликована: Янв. 1, 2023

Biomolecular condensates formed through the phase separation of proteins and nucleic acids are widely observed, offering a fundamental means organizing intracellular materials in membrane-less fashion. Traditionally, these have been regarded as homogeneous isotropic liquids. However, analogy with some synthetic copolymer systems, our recent theoretical research has demonstrated that model biomolecular can exhibit microemulsion-like internal structure, contingent upon specific sequence, inter-chain site-site interactions, concentrated polymer density. Motivated by considerations, here we present microscopic dynamical theory for self-diffusion constant viscosity simpler class systems - unentangled A/B regular multiblock solutions. Our approach integrates static equilibrium local microdomain scale structural information obtained from PRISM integral equation time evolution autocorrelation function monomer forces at center-of-mass level to determine diffusion weak caging regime far glass or gel transition. We focus on multi-block both simplicity its relevance macromolecular science. The impact sequence attraction strength slowing down mass transport flow due clustering enhanced collisional friction emergent ordering established. Analytic analysis metrics employed study identify key order parameters quantity how attractive forces, packing density above below crossover fluctuating polymeric microemulsion state.

Язык: Английский

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Phase Separation, Reaction Equilibrium, and Self-Assembly in Binary Telechelic Homopolymer Blends

Macromolecules, Год журнала: 2023, Номер 56(24), С. 9994 - 10005

Опубликована: Дек. 13, 2023

We study a binary blend of telechelic homopolymers that can form reversible AB-type bonds at the chain ends. Reversibly bonding polymers display novel material properties, including thermal tunability and self-healing, are not found in conventional covalently bonded polymers. Previous studies reversibly polymer systems have been limited by computational demand accounting for an infinite number possible reaction products spatially inhomogeneous, self-assembled structure. demonstrate newly developed theoretical models numerical methods enable simultaneous computation phase equilibrium, self-assembly via self-consistent field theory. Phase diagrams computed variety physically relevant conditions compared with nonreactive analogues as well previous experimental blends.

Язык: Английский

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