Soft Matter最新文献_第7页

Eyring theory for plasticity in amorphous polymers violates Curie's principle

IF 2.9 3区化学

Soft Matter Pub Date : 2025-03-03 DOI: 10.1039/D4SM00894D

Thomas C. Merlette, Elian Masnada, Paul Sotta and Didier R. Long

{"title":"Eyring theory for plasticity in amorphous polymers violates Curie's principle","authors":"Thomas C. Merlette, Elian Masnada, Paul Sotta and Didier R. Long","doi":"10.1039/D4SM00894D","DOIUrl":"10.1039/D4SM00894D","url":null,"abstract":"In 1936, Eyring introduced a model for plastic flow which still forms the bedrock of practically all studies on plasticity of glassy polymers. Though the concept of activated process he introduced is fundamentally relevant, we argue here that under no circumstances can the Eyring model be correct as it violates Curie's principle, which is a basic physical requirement of statistical mechanics. An alternative model was proposed by [Long et al., Phys. Rev. Mater., 2018, 2, 105601] to describe the acceleration of the dynamics by an applied stress, in which the elastic energy stored at the length scale of dynamical heterogeneities ξ ≈ 3 – 5 nm reduces the free energy barriers for relaxation. While this model still considers α-relaxation as an activated process, as did Eyring, it fully complies with Curie's principle. It is based on a Landau expansion of the free energy barriers as a function of the applied stress. We argue that, due to the large length scale involved in the α-relaxation, only the leading quadratic order term should be retained, as higher order terms are negligible. We discuss a few recent experiments which confirm these features. This model opens the way to set glassy polymers plasticity into the realm of out-of-equilibrium statistical physics and condensed matter physics, which we argue is the appropriate framework for considering the physics of glass transition and mechanical properties of glassy polymers.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2502-2508"},"PeriodicalIF":2.9,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565591","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}

引用次数: 0

Biomimetic swarm of active particles with coupled passive-active interactions.

IF 2.9 3区化学

Soft Matter Pub Date : 2025-03-03 DOI: 10.1039/d4sm01298d

Amir Nourhani

引用次数: 0

In situ error analysis in contact angle goniometry† 接触角测角仪的现场误差分析。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-28 DOI: 10.1039/D4SM01509F

Heikki A. Nurmi, Gentrit Zenuni, Sakari Lepikko, Reetta Saine, Maja Vuckovac and Robin H. A. Ras

{"title":"In situ error analysis in contact angle goniometry†","authors":"Heikki A. Nurmi, Gentrit Zenuni, Sakari Lepikko, Reetta Saine, Maja Vuckovac and Robin H. A. Ras","doi":"10.1039/D4SM01509F","DOIUrl":"10.1039/D4SM01509F","url":null,"abstract":"Contact angle goniometry is a valuable tool for characterising surface wetting properties in various application areas such as petrochemistry, coatings, and medicine. The accuracy of goniometer measurements is often unknown and underappreciated, yet the errors can be large enough to affect or invalidate the interpretation of measurement. In addition, goniometer measurement errors are typically estimated after the measurement by the variance of the measured data, without considering the instrumental uncertainties in the analysis or in the setup. Here, we present a method for estimating these intrinsic measurement errors for each frame in situ and validate it against a commercial contact angle goniometer. We evaluate the method using synthetic images of a droplet with set contact angles. Our results highlight the need for in situ error estimates in goniometer measurements, as the errors can be larger than generally estimated ones. The presented in situ error estimation method could be implemented using contact angle goniometer software to aid the user during the tuning of the instrument and analysis of the contact angle data.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2422-2429"},"PeriodicalIF":2.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sm/d4sm01509f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143522211","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}

引用次数: 0

Computer vision for high-throughput analysis of pickering emulsions†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-28 DOI: 10.1039/D4SM01252F

Kieran D. Richards, Ella Comish and Rachel C Evans

{"title":"Computer vision for high-throughput analysis of pickering emulsions†","authors":"Kieran D. Richards, Ella Comish and Rachel C Evans","doi":"10.1039/D4SM01252F","DOIUrl":"10.1039/D4SM01252F","url":null,"abstract":"The quanitative analysis of solid-particle stabilized emulsions, known as Pickering emulsions, is crucial for their application in food, cosmetics, and pharmaceuticals. However, size analysis of these emulsion droplets, with diameters ranging from 5 to 500 μm, is challenging due to their non-uniform spatial and polydisperse size-distribution. Here, we investigate the application of the circle-Hough transform (CHT), a well-established computer-vision technique characterised by its ability to detect circular features in noisy images, for the seldom explored quantitative assessment of droplet size from optical microscopy images. This is particularly relevant to images where emulsions are captured in a single 2D focal plane. To implement the CHT with optical images, we have developed an open-source software application (“Hough-Scan”), which incorporates a user-friendly graphical interface for ease of use, and a tiling algorithm allowing localised regions of circles to be processed in parallel and improving computational efficiency. Using Hough-Scan, we demonstrate that the CHT has superior precision, recall and accuracy for the identification of Pickering emulsion droplets and determination of their size, compared to both manual identification and established computer vision methods. Our study demonstrates that CHT implementation using Hough-Scan can significantly increase the ease of image analysis for a diverse range of Pickering emulsion systems of varying spatial and size distribution, as well as visual artefacts common to example microscopy images.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 12","pages":" 2339-2348"},"PeriodicalIF":2.9,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sm/d4sm01252f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143522122","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}

引用次数: 0

A refined mechanistic model for swelling kinetics of starch granules.

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-26 DOI: 10.1039/d4sm00980k

Botong Li, Lanxin Mo, Vivek Narsimhan, Ganesan Narsimhan, John M Frostad

{"title":"A refined mechanistic model for swelling kinetics of starch granules.","authors":"Botong Li, Lanxin Mo, Vivek Narsimhan, Ganesan Narsimhan, John M Frostad","doi":"10.1039/d4sm00980k","DOIUrl":"https://doi.org/10.1039/d4sm00980k","url":null,"abstract":"This paper investigates the gelatinization of individual starch granules using numerical simulations, validated against experimental microscopy data from a ParCS apparatus. We show that the dynamics of starch-granule swelling can be captured by a diffusion equation for mass transfer of water into the granule, with the equilibrium water content captured by a Flory-Rehner theory of a cross-linked network in which the fraction of cross-linked chains is made to vary as an empirical function of temperature. Having the cross-link density vary with temperature is vital to capture the swelling behavior at large and small swelling extents (i.e., close to and far away from the gelatinization temperature). The theory produces excellent agreement with both equilibrium swelling data and dynamic swelling data for red bean starch. Further, we show that the model is able to reproduce a previous experimental finding that swelling data from different granules from red bean, chickpea, green lentil, and yellow pea starches can be collapsed onto a universal curve with only two empirical parameters. The simulations are then used to predict the relationship between the empirical parameters in the master curve and the true material properties. The modified theory presented here is a major step forward in the fundamental understanding of starch gelatinization and the ability to use predictive models for optimization of industrial manufacturing processes.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143497725","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}

引用次数: 0

Correction: Room-temperature ferroelectric nematic liquid crystal showing a large and diverging density 更正：室温铁电向列液晶显示出较大的发散密度。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-26 DOI: 10.1039/D5SM90035B

Charles Parton-Barr, Helen F. Gleeson and Richard J. Mandle

引用次数: 0

Spontaneous generation of angular momentum in chiral active crystals

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-26 DOI: 10.1039/D4SM01426J

Umberto Marini Bettolo Marconi and Lorenzo Caprini

{"title":"Spontaneous generation of angular momentum in chiral active crystals","authors":"Umberto Marini Bettolo Marconi and Lorenzo Caprini","doi":"10.1039/D4SM01426J","DOIUrl":"10.1039/D4SM01426J","url":null,"abstract":"We study a two-dimensional chiral active crystal composed of underdamped chiral active particles. These particles, characterized by intrinsic handedness and persistence, interact via linear forces derived from harmonic potentials. Chirality plays a pivotal role in shaping the system's behavior: it reduces displacement and velocity fluctuations while inducing cross-spatial correlations among different Cartesian components of velocity. These features distinguish chiral crystals from their non-chiral counterparts, leading to the emergence of net angular momentum, as predicted analytically. This angular momentum, driven by the torque generated by the chiral active force, exhibits a non-monotonic dependence on the degree of chirality. Additionally, it contributes to the entropy production rate, as revealed through a path-integral analysis. We investigate the dynamic properties of the crystal in both Fourier and real space. Chirality induces a non-dispersive peak in the displacement spectrum, which underlies the generation of angular momentum and oscillations in time-dependent autocorrelation functions or mean-square displacement, all of which are analytically predicted.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 14","pages":" 2586-2606"},"PeriodicalIF":2.9,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603257","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}

引用次数: 0

The role of phosphate in silk fibroin self-assembly: a Hofmeister study†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-26 DOI: 10.1039/D4SM01198H

Caleb Wigham, Vrushali Varude, Henry O’Donnell and R. Helen Zha

{"title":"The role of phosphate in silk fibroin self-assembly: a Hofmeister study†","authors":"Caleb Wigham, Vrushali Varude, Henry O’Donnell and R. Helen Zha","doi":"10.1039/D4SM01198H","DOIUrl":"10.1039/D4SM01198H","url":null,"abstract":"Silk fibroin is the primary protein component of the threads of Bombyx mori silkworm cocoons. Previous work has demonstrated that silk fibroin can self-assemble at solid–liquid interfaces to form dense, nanothin coatings that grow continuously from a substrate surface when exposed to potassium phosphate, a kosmotropic salt. Herein, the role of potassium phosphate in promoting silk fibroin self-assembly in solution and on surfaces is studied and compared to other salts in the Hofmeister series. Results show that strong kosmotropes, such as ammonium sulfate and potassium phosphate, promote a bimodal distribution of assembled species in solution that is indicative of a nucleation-growth mechanism. Interestingly, silk fibroin assemblies formed by potassium phosphate contain the highest β-sheet content, suggesting that phosphate-specific interactions play a role in silk fibroin self-assembly. In the presence of kosmotropic salts, silk fibroin nanoaggregates continuously accumulate at solid–liquid interfaces with varying early- and late-stage adsorption rates. Interfacial coatings formed in the presence of potassium phosphate are smooth, dense, and completely cover the underlying substrate without evidence of large-scale aggregation, whereas other kosmotropes generate rough, heterogeneous coatings. These studies thus decouple the kosmotropic effects of phosphate (via disruption of the protein hydration shell) from ion-specific behavior in driving silk fibroin self-assembly.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2461-2470"},"PeriodicalIF":2.9,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sm/d4sm01198h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143539617","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}

引用次数: 0

Microstructural evolution in drying colloidal films driven by evaporation and sedimentation: lattice Boltzmann simulation and a mathematical model†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01498G

Jinseong Yun, Byoungjin Chun and Hyun Wook Jung

{"title":"Microstructural evolution in drying colloidal films driven by evaporation and sedimentation: lattice Boltzmann simulation and a mathematical model†","authors":"Jinseong Yun, Byoungjin Chun and Hyun Wook Jung","doi":"10.1039/D4SM01498G","DOIUrl":"10.1039/D4SM01498G","url":null,"abstract":"Understanding the temporal evolution of particle distribution during the drying of colloidal films is essential for advancing the design and optimization of film properties. This study investigates the dynamics of colloidal particles during vertical drying using the lattice Boltzmann method. Simulation results reveal that the particle distribution during drying and the resulting film microstructure are governed by two key dimensionless numbers: the drying Péclet number (Pe) and the sedimentation Péclet number (Pesed). When the evaporation rate exceeds the sedimentation rate (Pe ≫ Pesed), particles accumulate near the air–liquid interface, ultimately forming a colloidal crystal in the top layer. Conversely, when sedimentation dominates (Pe ≪ Pesed), similar accumulation and crystallization occur near the bottom substrate. These findings underscore the critical influence of drying and sedimentation dynamics on the final microstructural quality of colloidal films. To complement the simulation results, a one-dimensional mathematical drying model is developed, incorporating hydrodynamic hindrance and collective diffusivity effects resulting from particle accumulation. This model demonstrates quantitative agreement with simulation results across a wide range of Pe and Pesed. Using this model, new drying regime maps are constructed in the Pe and Pesed spaces, delineating distinct regions dominated by evaporation, diffusion, or sedimentation.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2430-2444"},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536163","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}

引用次数: 0

Adhesion study at the interface of a PDMS-elastomer and borosilicate glass-slide: effect of modulus and thickness of the elastomer

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01249F

Susheel Kumar, Chiranjit Majhi, Krishnacharya Khare and Manjesh K. Singh

{"title":"Adhesion study at the interface of a PDMS-elastomer and borosilicate glass-slide: effect of modulus and thickness of the elastomer","authors":"Susheel Kumar, Chiranjit Majhi, Krishnacharya Khare and Manjesh K. Singh","doi":"10.1039/D4SM01249F","DOIUrl":"10.1039/D4SM01249F","url":null,"abstract":"Adhesion control at the interface of two surfaces is crucial in many applications. Examples are the design of micro and nanodevices such as microfluidic devices, biochips, and electronic sensors. Adhesion at the interface of two materials can be controlled by various methods, such as chemical treatment on the surface of the materials, modification of the surface texture of the materials, and change of the mechanical properties of the materials. The main idea of this study is to control the adhesion by changing the mechanical properties (modulus) of the polydimethylsiloxane (PDMS) elastomer. We vary the modulus of the PDMS elastomer by changing mixing ratio (w/w) of the silicone elastomer base and its curing agent (SylgardTM 184, Dow Corning). Our study also includes the effect of the thickness of the PDMS elastomer sheet on its adhesion behavior. Adhesion measurements at the interface of the borosilicate glass slide and different PDMS elastomer specimens were performed using a wedge test. This method inserts a glass coverslip at the interface to create a wedge. We observe a significant decrease in the work of adhesion and an increase in equilibrium crack length with an increase in elastic-modulus and thickness of the PDMS elastomer samples. We present and discuss the effect of modulus and specimen-thickness on the adhesion behavior of the PDMS elastomer against a glass slide.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2493-2501"},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565590","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}

引用次数: 0