{"title":"Molecular Simulation of Effects of Network Structure on Fracture Behavior of Gels Synthesized by Radical Polymerization","authors":"Tsutomu Furuya, Tsuyoshi Koga","doi":"10.1021/acs.macromol.4c02875","DOIUrl":null,"url":null,"abstract":"The synthesis of high-strength gels with many entanglements by radical polymerization with high monomer and low cross-linker concentrations has recently been reported by several groups. In order to elucidate the toughening mechanism of such high-strength gels, the fracture behavior of gels synthesized by radical polymerization is studied by a coarse-grained molecular dynamics simulation. The simulation results qualitatively reproduce the reported experimental results; the gels formed with high monomer and low cross-linker concentrations have a small number of elastically effective chains due to cross-linking, but many polymer entanglements, and exhibit high toughness without sacrificing the shear modulus. In the tough gels, the structural changes that suppress the orientation of the polymer chains in the elongation direction and stress concentration are confirmed. Analysis of the relationship between network structure and fracture behavior reveals that the chain length between cross-linking points and the number of entanglements are important for the toughness of the gels.","PeriodicalId":51,"journal":{"name":"Macromolecules","volume":"92 1","pages":""},"PeriodicalIF":5.1000,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Macromolecules","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.macromol.4c02875","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"POLYMER SCIENCE","Score":null,"Total":0}
引用次数: 0
Abstract
The synthesis of high-strength gels with many entanglements by radical polymerization with high monomer and low cross-linker concentrations has recently been reported by several groups. In order to elucidate the toughening mechanism of such high-strength gels, the fracture behavior of gels synthesized by radical polymerization is studied by a coarse-grained molecular dynamics simulation. The simulation results qualitatively reproduce the reported experimental results; the gels formed with high monomer and low cross-linker concentrations have a small number of elastically effective chains due to cross-linking, but many polymer entanglements, and exhibit high toughness without sacrificing the shear modulus. In the tough gels, the structural changes that suppress the orientation of the polymer chains in the elongation direction and stress concentration are confirmed. Analysis of the relationship between network structure and fracture behavior reveals that the chain length between cross-linking points and the number of entanglements are important for the toughness of the gels.
期刊介绍:
Macromolecules publishes original, fundamental, and impactful research on all aspects of polymer science. Topics of interest include synthesis (e.g., controlled polymerizations, polymerization catalysis, post polymerization modification, new monomer structures and polymer architectures, and polymerization mechanisms/kinetics analysis); phase behavior, thermodynamics, dynamic, and ordering/disordering phenomena (e.g., self-assembly, gelation, crystallization, solution/melt/solid-state characteristics); structure and properties (e.g., mechanical and rheological properties, surface/interfacial characteristics, electronic and transport properties); new state of the art characterization (e.g., spectroscopy, scattering, microscopy, rheology), simulation (e.g., Monte Carlo, molecular dynamics, multi-scale/coarse-grained modeling), and theoretical methods. Renewable/sustainable polymers, polymer networks, responsive polymers, electro-, magneto- and opto-active macromolecules, inorganic polymers, charge-transporting polymers (ion-containing, semiconducting, and conducting), nanostructured polymers, and polymer composites are also of interest. Typical papers published in Macromolecules showcase important and innovative concepts, experimental methods/observations, and theoretical/computational approaches that demonstrate a fundamental advance in the understanding of polymers.