Elucidations of Structure and Molecular Dynamics of Complex Polymers by State-of-the-Art Solid-State NMR Spectroscopy

Macromolecules, Journal Year: 2024, Volume and Issue: 57(5), P. 1893 - 1918

Published: Feb. 28, 2024

Solid-state nuclear magnetic resonance (ssNMR) has been playing an indispensable role in revealing the interplay of structure and molecular dynamics polymers at different states. In this Perspective, we first provide overview about fundamental spin interactions ssNMR then highlight some recent progress on sensitivity-enhanced spectroscopy situ NMR. Moreover, applications field polymer crystallization, dynamics, chemical reactions, supramolecular polymers, energy materials, so on. Finally, our personal perspective is given future development crossroad science.

Language: Английский

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Discrete Block Copolymers: Precision Engineering on Multiple Length Scales

Macromolecules, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 26, 2025

Language: Английский

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Glass Formation in Ring Polymer Melts Having Variable Knot Complexity and Molecular Mass

Macromolecules, Journal Year: 2024, Volume and Issue: 57(14), P. 6875 - 6896

Published: July 8, 2024

The variation of polymer topology provides an alternative way to tune the properties materials without varying chemistry monomers composing and a powerful approach creating new functional testing ideas about molecular transport in fluids having broad theoretical significance science. Here, we focus on flexible ring melts by coarse-grained dynamics simulations, where rings have fixed knot complexity defined minimal crossing number mc, explore how basic thermodynamic segmental dynamic are impacted mc mass M. We find that increasing has similar influence density, thermal expansion coefficient, radius gyration, overall average shape, along with characteristic temperatures glass formation fragility, as recently found upon star arms f defines corresponding measure topological complexity. common trend these distinct classes polymers can be understood from generalized entropy theory, based alters packing frustration, quantified dimensionless coefficient isothermal compressibility. These findings confirm striking frustration is key factor determining glass-forming liquids. Notably, effect knotting was hardly considered previous simulation experimental studies polymers, which akin ignoring case so suggest might source some variability measurements addition linear contaminants.

Language: Английский

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Single-Chain Slip-Spring Simulation for Entangled Nonconcatenated Ring Polymer Melts

Macromolecules, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 3, 2025

Language: Английский

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Entropic Repulsion and Local Order in Doubly Tethered Polymers on a Surface

Macromolecular Theory and Simulations, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 20, 2025

Abstract The behavior of (athermal) mobile doubly tethered polymers (ring‐like in 3D) is investigated, on a 2D substrate using the bond fluctuation model. end‐monomers can move laterally within constrained distance range. Conformational properties loop are analyzed and specifically ordering system end‐monomers. For this, director considered between for local ordering. As tethering density increases, transition from mushroom‐like conformations to nearly upright structures observed, as case linear grafted polymers. effects repulsion explored, i.e., entropic repulsion, order parameter orientational correlations directors 2D. Despite lack global phase transition, emerges due interactions 3D.

Language: Английский

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DNA Transport is Topologically Sculpted by Active Microtubule Dynamics

PRX Life, Journal Year: 2025, Volume and Issue: 3(1)

Published: March 13, 2025

The transport of macromolecules, such as DNA, through the cytoskeleton is critical to wide-ranging cellular processes from cytoplasmic streaming transcription. rigidity and steric hindrances imparted by network filaments comprising often leads anomalous subdiffusion, while active motor-driven restructuring can induce athermal superdiffusion. Understanding interplay between these seemingly antagonistic contributions intracellular dynamics remains a grand challenge. Here, we use single-molecule tracking show that large linear relaxed circular DNA microtubule networks be non-Gaussian multimodal, with degree spatiotemporal scales over which features manifest depending nontrivially on state activity topology. For example, increases caging modes dampening mechanisms for DNA. We further discover molecules exhibit either markedly enhanced subdiffusion or superdiffusion compared their counterparts, in absence presence kinesin activity, indicative microtubules threading This strong coupling both stalling directed transport, providing direct route towards parsing distinct determining impact signatures. More generally, leveraging macromolecular topology programming molecular interactions an elegant yet largely overlooked mechanism cells may exploit trafficking, streaming, compartmentalization. could harnessed design self-regulating, sensing, reconfigurable biomimetic matter. Published American Physical Society 2025

Language: Английский

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Entropic Contribution to the Nonlinear Mechanical Properties of Thermoplastic Elastomers

Macromolecules, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 4, 2025

Language: Английский

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Controlled synthesis of β-cyclodextrin-based starlike helical poly(phenyl isocyanide) and its application in chiral resolution

Carbohydrate Polymers, Journal Year: 2025, Volume and Issue: 357, P. 123456 - 123456

Published: Feb. 28, 2025

Language: Английский

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Understanding Local Conformation in Cyclic and Linear Polymers Using Molecular Dynamics and Point Cloud Neural Network

Chinese Journal of Polymer Science, Journal Year: 2025, Volume and Issue: unknown

Published: March 3, 2025

Language: Английский

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Loop-Extruder-Mediated Rigidity Can Globally Order Bacterial Chromosomes

PRX Life, Journal Year: 2025, Volume and Issue: 3(1)

Published: March 7, 2025

Many bacterial chromosomes show large-scale linear order, so that a locus's genomic position correlates with its along the cell. In model organism , for instance, left and right arms of circular chromosome lie in different cell halves. However, no mechanisms anchor loci to poles have been identified, it remains unknown how this so-called “left--right” organization arises. Here we construct biophysical explains global order could be established via an active loop extrusion mechanism. Our assumes motor protein complex MukBEF extrudes loops on most but is excluded from terminal region by MatP, giving rise partially looped ring polymer structure. Using three-dimensional simulations chromosome, find our can display stable left--right chromosomal parameter regime consistent prior experiments. We explain behavior considering effect bending rigidity derive necessary conditions emerge. Finally, develop phase diagram system, where emerges when size large enough compacted enough. work provides theoretical mechanistic explanation loop-extruders establish leads accurate gene positioning within cell, without locus anchoring. Published American Physical Society 2025

Language: Английский

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