Macromolecular Theory and Simulations最新文献_第8页

Volumetric and Energetic Properties of Polystyrene and Polyethylene Oxide Affected by Thermal Cycling 热循环对聚苯乙烯和聚氧乙烯体积和能量性能的影响

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-04-06 DOI: 10.1002/mats.202300008

Benoit Minisini, Armand Soldera

{"title":"Volumetric and Energetic Properties of Polystyrene and Polyethylene Oxide Affected by Thermal Cycling","authors":"Benoit Minisini, Armand Soldera","doi":"10.1002/mats.202300008","DOIUrl":"10.1002/mats.202300008","url":null,"abstract":"Polymers are known to exhibit hysteresis in their thermal and volumetric properties between cooling and heating at the glass transition. A thorough investigation of this hysteresis using atomistic simulation is not proposed until now. In this work, therefore, the glass transition is studied through heating and cooling protocols at constant rate for two polymers, polystyrene (PS) and polyethylene oxide (PEO), with different molecular weights. To achieve this objective, the analysis is carried out by plotting against temperature, specific volume, coefficient of thermal expansion, total energy, and constant volume heat capacity. The calculated properties for PS and PEO are found to be in good agreement with experimental data, confirming the accuracy of the TraPPE force field for these polymers. The glass transition temperature (Tg) range remains the same regardless of the properties. Moreover, the difference in properties between heating and cooling processes systematically leads to a peak at the same temperature, associated with Tg. Finally, starting from a low temperature, the polymer chains remain mainly in a potential well as the temperature rises, while during cooling the exploration of the configuration space continues up to the temperature where no torsional changes are observed.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"32 4","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mats.202300008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45275990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Masthead: Macromol. Theory Simul. 2/2023 刊头：Macromol。理论模拟。2023年2月

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-03-20 DOI: 10.1002/mats.202370004

引用次数: 0

Molecular Simulation and Experimental Study on the Damping and Aging Properties of 4010NA/Hydrogenated Nitrile Butadiene/Nitrile Butadiene Rubber Composites 4010NA/氢化丁腈/丁腈橡胶复合材料阻尼老化性能的分子模拟与实验研究

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-03-20 DOI: 10.1002/mats.202370003

Meng Song, Meng Wang, Chaole Wang, Jihong Song, Yunan Li, Fengyi Cao, Guomin Yu, Qi Qin

引用次数: 0

Monte Carlo Simulation of Long Hard-Sphere Polymer Chains in Two to Five Dimensions 二至五维长硬球聚合物链的蒙特卡罗模拟

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-03-18 DOI: 10.1002/mats.202200080

Stefan Schnabel, Wolfhard Janke

引用次数: 1

Retrosynthetic and Synthetic Reaction Prediction Model Based on Sequence-to-Sequence with Attention for Polymer Designs 注意聚合物设计的基于序列对序列的反合成和合成反应预测模型

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-03-17 DOI: 10.1002/mats.202300011

Hiroaki Taniwaki, Hiromasa Kaneko

引用次数: 0

Atomistic MD Simulations of n-Alkanes in a Phospholipid Bilayer: CHARMM36 versus Slipids 磷脂双层中n-烷烃的原子MD模拟：CHARMM36与Slipid

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-03-12 DOI: 10.1002/mats.202200078

Anika Wurl, Tiago M. Ferreira

{"title":"Atomistic MD Simulations of n-Alkanes in a Phospholipid Bilayer: CHARMM36 versus Slipids","authors":"Anika Wurl, Tiago M. Ferreira","doi":"10.1002/mats.202200078","DOIUrl":"10.1002/mats.202200078","url":null,"abstract":"Linear alkanes (n-alkanes) are chemically the most simple linear hydrophobic molecules in nature. Studying the incorporation of n-alkanes into lipid membranes is therefore a good starting point toward understanding the behavior of hydrophobic molecules in lipid membranes and to assess how accurately molecular dynamics models describe such systems. Here, the miscibility and structure of different n-alkanes—n-decane (C10), n-eicosane (C20), and n-triacontane (C30)—in dipalmitoylphosphatidylcholine membranes are investigated using two of the most used force fields for lipid membrane molecular dynamics simulations (CHARMM36 and Slipids). The n-alkanes are miscible in the membrane up to a critical volume fraction, ϕc, that depends on the force field interaction parameters used. ϕc is dependent on alkane chain length only for the model with more disordered chains (Slipids). Below ϕc, a comparison with 2H nuclear magnetic resonance (NMR) spectra indicates that a more realistic structure of the longer alkane molecules (C20 and C30) is obtained using the Slipids force field. On the other hand, for the shorter alkane (C10), Slipids simulations underestimate molecular order and CHARMM36 simulations enable a precise prediction of its experimental spectrum. The predicted 2H NMR spectra are highly sensitive to 1–4 electrostatic interactions, and suggest that a reduction of the partial charges of the longer alkanes and acyl chains in CHARMM36 results in a better performance. The results presented indicate that lipid membranes with incorporated alkanes are highly valuable systems for the validation of force fields designed to perform lipid membrane simulations.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"32 3","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mats.202200078","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47374056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Predicting Multi-Component Phase Equilibria of Polymers using Approximations to Flory–Huggins Theory 用Flory-Huggins理论的近似值预测聚合物的多组分相平衡

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-02-24 DOI: 10.1002/mats.202300001

Stijn H. M. van Leuken, Rolf A. T. M. van Benthem, Remco Tuinier, Mark Vis

{"title":"Predicting Multi-Component Phase Equilibria of Polymers using Approximations to Flory–Huggins Theory","authors":"Stijn H. M. van Leuken, Rolf A. T. M. van Benthem, Remco Tuinier, Mark Vis","doi":"10.1002/mats.202300001","DOIUrl":"10.1002/mats.202300001","url":null,"abstract":"The rational development of sustainable polymeric materials demands tunable properties using mixtures of polymers with chemical variations. At the same time, the sheer number of potential variations and combinations makes experimentally or numerically studying every new mixture impractical. A direct predictive tool quantifying how material properties change when molecular features change provides a less time- and resource-consuming route to optimization. Numerically solving Flory–Huggins theory provides such a tool for mono-disperse mixtures with a limited number of components, but for multi-component systems the large number of equations makes numerical computations challenging. Approximate solutions to Flory–Huggins theory relating miscibility and solubility to molecular features are presented. The set of approximate relations show a wider range of accuracy compared to existing approximations. The combination of the analytical, lower-order, and more accurate higher-order approximations together contribute to a broader applicability and extensibility of Flory–Huggins theory.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"32 4","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/mats.202300001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45001968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Secondary Structure Formation in Hybrid Synthetic/Peptide Polymers: Insights from Molecular Dynamics Simulations 合成/肽杂化聚合物二级结构形成的分子动力学模拟研究

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-02-23 DOI: 10.1002/mats.202200070

Thomas Kunze, Christian Dreßler, Daniel Sebastiani

引用次数: 0

Emergence and Stability of Hierarchical Structures under Cylindrical Confinement 圆柱约束下层次结构的产生与稳定性

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-02-22 DOI: 10.1002/mats.202200076

Tiancheng Chen, Yuci Xu

{"title":"Emergence and Stability of Hierarchical Structures under Cylindrical Confinement","authors":"Tiancheng Chen, Yuci Xu","doi":"10.1002/mats.202200076","DOIUrl":"10.1002/mats.202200076","url":null,"abstract":"Focusing on the formation of hierarchical structure under cylindrical confinement, the self-assembly of A(BC)2B multiblock copolymer of chain length N in a nanopore with size R is studied using the self-consistent field theory. The hierarchical concentric ring (HCk), hierarchical perforated cylinder (HPk), hierarchical helix (HHk), and even hierarchical disk (HDk) is obtained with different number of mid-thin layers k via a proposed design principle. The results show that large pore size and χAB favor the hierarchical structure with more k, while χBC prefers hierarchical structure with less k, consistent with the results of hierarchical structure in bulk. By investigating the effect of the volume fraction of the tail A block (fA), the phase transition sequence, HCk → HPk → HHk → HDk is explored, which shares the same transition of multiblock copolymer in bulk with Lk → Gk → Ck → Sk. Finally, the phase diagram with respect to the fA and R is explored, where the stability regime of these hierarchical structures is well understood. The results provide a compelling panacea for the fabrication of hierarchical 3D nanostructures under confinement.","PeriodicalId":18157,"journal":{"name":"Macromolecular Theory and Simulations","volume":"32 3","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42836221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Masthead: Macromol. Theory Simul. 1/2023 刊头：Macromol。理论模拟。2023年1月

IF 1.4 4区工程技术

Macromolecular Theory and Simulations Pub Date : 2023-01-19 DOI: 10.1002/mats.202370002

引用次数: 0