{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T11:19:12Z","timestamp":1785410352867,"version":"3.56.0"},"reference-count":34,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:00:00Z","timestamp":1782259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key R&D Program of China","doi-asserted-by":"publisher","award":["2024YFF0508400"],"award-info":[{"award-number":["2024YFF0508400"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["52273080"],"award-info":[{"award-number":["52273080"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["12302481"],"award-info":[{"award-number":["12302481"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["52273080"],"award-info":[{"award-number":["52273080"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["12302481"],"award-info":[{"award-number":["12302481"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Foshan Xianhu Laboratory Project","award":["XHD2024-12134142-02"],"award-info":[{"award-number":["XHD2024-12134142-02"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Bisphenol A type epoxy resin has the problem of relatively high brittleness after curing. Although traditional polysiloxane toughening methods can improve toughness, they often come at the expense of strength. In this paper, methylphenyl dimethoxysilane (MPS) was used as a monomer to synthesize end-hydroxyl poly(methylphenyl)siloxane (PMPS), which was then used to modify E51 epoxy resin. The structure and reaction degree were characterized by infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, matrix-assisted laser desorption\/ionization time-of-flight\/time-of-flight mass spectrometry and viscosity tests. The mechanical test results show that when the PMPS content is 20 wt%, the tensile, flexural, compressive and impact strengths of the modified resin increase by 31.26%, 26.16%, 18.53% and 98.66%, respectively, compared with the unmodified resin, and the tensile and flexural elastic moduli increase by 38.36% and 32.25%, respectively. The fracture toughness increases by 60.29%, indicating that the strength, stiffness and toughness of the material have all been improved. Dynamic mechanical analysis shows that the glass transition temperature and crosslinking density of the system gradually decrease with increasing PMPS content. Thermogravimetric analysis shows that the introduction of PMPS increases the char yield and decreases the maximum thermal decomposition rate, thereby enhancing the thermal stability of the system. Microscopic morphology analysis by optical microscopy, scanning electron microscopy and atomic force microscopy shows that the system has good compatibility, and the internal different modulus phases are distributed in a network-like manner, forming a uniform co-continuous or bicontinuous phase structure. This structure effectively promotes stress transfer and energy dissipation, alleviates local stress concentration, and thus comprehensively improves the mechanical properties of the resin system.<\/jats:p>","DOI":"10.3390\/polym18131569","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T07:57:24Z","timestamp":1782287844000},"page":"1569","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Phase Structure and Mechanical Properties of Epoxy Resin Modified with Hydroxyl-Terminated Poly(methylphenylsiloxane)"],"prefix":"10.3390","volume":"18","author":[{"given":"Xixuan","family":"He","sequence":"first","affiliation":[{"name":"School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yundong","family":"Ji","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Zhao","sequence":"additional","affiliation":[{"name":"School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhenxiang","family":"Guan","sequence":"additional","affiliation":[{"name":"China Railway 19 Bureau Group Co., Ltd., Beijing 100176, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dongfeng","family":"Cao","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhentao","family":"Luo","sequence":"additional","affiliation":[{"name":"Aerospace Science and Industry Wuhan Magnetism-Electron Co., Ltd., Wuhan 430070, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shuxin","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, China"},{"name":"Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory, Foshan 528000, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"100977","DOI":"10.1016\/j.pmatsci.2022.100977","article-title":"Toughness and Its Mechanisms in Epoxy Resins","volume":"130","author":"Mi","year":"2022","journal-title":"Prog. Mater. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/15583724.2019.1650063","article-title":"Multifunctionality in Epoxy Resins","volume":"60","author":"Capricho","year":"2020","journal-title":"Polym. Rev."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"9687","DOI":"10.1016\/S0032-3861(01)00474-8","article-title":"Network Chain Orientation in the Toughening Process of the Elastomer Modified Mesogenic Epoxy Resin","volume":"42","author":"Ochi","year":"2001","journal-title":"Polymer"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1134\/S1560090416010048","article-title":"Improvement of the Impact and Crack Resistance of Epoxy Thermosets and Thermoset-Based Composites with the Use of Thermoplastics as Modifiers","volume":"58","author":"Lobanov","year":"2016","journal-title":"Polym. Sci. Ser. B"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1723","DOI":"10.1080\/03602559.2014.919658","article-title":"Synthesis and Modifications of Epoxy Resins and Their Composites: A Review","volume":"53","author":"Paluvai","year":"2014","journal-title":"Polym.-Plast. Technol. Mater."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"22316","DOI":"10.1016\/j.ceramint.2021.05.083","article-title":"Role of Non-Functionalized Oxide Nanoparticles on Mechanical Properties and Toughening Mechanisms of Epoxy Nanocomposites","volume":"47","author":"Goyat","year":"2021","journal-title":"Ceram. Int."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Barra, G., Guadagno, L., Raimondo, M., Santonicola, M.G., Toto, E., and Vecchio Ciprioti, S. (2023). A Comprehensive Review on the Thermal Stability Assessment of Polymers and Composites for Aeronautics and Space Applications. Polymers, 15.","DOI":"10.3390\/polym15183786"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Santiago, D., and Serra, \u00c0. (2022). Enhancement of Epoxy Thermosets with Hyperbranched and Multiarm Star Polymers: A Review. Polymers, 14.","DOI":"10.3390\/polym14112228"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"627","DOI":"10.1002\/pol.20210044","article-title":"Synthesis and Performance of Flexible Epoxy Resin with Long Alkyl Side Chains via Click Reaction","volume":"59","author":"Dai","year":"2021","journal-title":"J. Polym. Sci."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4256","DOI":"10.14233\/ajchem.2013.13936","article-title":"Synthesis and Properties of a Flexible Curing Agent","volume":"25","author":"Wang","year":"2013","journal-title":"Asian J. Chem."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"van Driel, W.D., and Yazdan Mehr, M. (2022). Reliability of Organic Compounds in Microelectronics and Optoelectronics, Springer.","DOI":"10.1007\/978-3-030-81576-9"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"60685","DOI":"10.1039\/C4RA09230A","article-title":"The Effect of Epoxy\u2013Silicone Copolymer Content on the Thermal and Mechanical Properties of Cured Epoxy Resin Modified with Siloxane","volume":"4","author":"Chen","year":"2014","journal-title":"RSC Adv."},{"key":"ref_13","unstructured":"May, C.A. (1988). Epoxy Resins: Chemistry and Technology, Marcel Dekker. [2nd ed.]."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"128822","DOI":"10.1016\/j.matchemphys.2023.128822","article-title":"Investigation of Hydroxyl-Terminated Polydimethylsiloxane-Modified Epoxy Resin","volume":"313","author":"Xie","year":"2024","journal-title":"Mater. Chem. Phys."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"107820","DOI":"10.1016\/j.polymertesting.2022.107820","article-title":"Enhancement of Polysiloxane\/Epoxy Resin Compatibility through an Electrostatic and van Der Waals Potential Design Strategy","volume":"117","author":"Liu","year":"2023","journal-title":"Polym. Test."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1016\/j.eurpolymj.2019.05.002","article-title":"Fabrication of Epoxy Modified Polysiloxane with Enhanced Mechanical Properties for Marine Antifouling Application","volume":"117","author":"Sun","year":"2019","journal-title":"Eur. Polym. J."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"97413","DOI":"10.1039\/C5RA18399E","article-title":"A Novel Epoxy-Functionalized Hyperbranched Polysiloxane (HPSi) Endowing Methyl Phenyl Silicone Resin (Si603)\/Epoxy Systems with Enhanced Compatibility and Fire Retardancy Performance","volume":"5","author":"Jia","year":"2015","journal-title":"RSC Adv."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Ji, Y.D., Pan, J., Xu, C.X., and Cao, D.F. (2025). Effects of Phase Structure Regulation on Properties of Hydroxyl-Terminated Polyphenylpropylsiloxane-Modified Epoxy Resin. Polymers, 17.","DOI":"10.3390\/polym17152099"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"127368","DOI":"10.1016\/j.polymer.2024.127368","article-title":"Phenyl Propyl Polysiloxane Modified Epoxy Resin I: The Content, Phase Structures and Macroproperties","volume":"308","author":"Wang","year":"2024","journal-title":"Polymer"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"127665","DOI":"10.1016\/j.polymer.2024.127665","article-title":"Phenyl, Propyl Polysiloxane Modified Epoxy Resin II: The Co-Continuous Phase, Concurrently Strengthening and Toughening Mechanism","volume":"313","author":"Wang","year":"2024","journal-title":"Polymer"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"e56519","DOI":"10.1002\/app.56519","article-title":"Phenyl Propyl Polysiloxane-Modified Epoxy Resin III: The Reaction Condition, Phase Structures, and Macroproperties","volume":"142","author":"Ji","year":"2025","journal-title":"J. Appl. Polym. Sci."},{"key":"ref_22","unstructured":"(2023). Determinating the Epoxy Value of Plasticizers (Standard No. GB\/T 1677-2023)."},{"key":"ref_23","unstructured":"(2021). Test Methods for Properties of Resin Casting Body (Standard No. GB\/T 2567-2021)."},{"key":"ref_24","unstructured":"(2022). Plastics\u2014Determination of Fracture Toughness (GIC and KIC)\u2014Linear Elastic Fracture Mechanics (LEFM) Approach (Standard No. GB\/T 41932-2022)."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"248","DOI":"10.1016\/j.porgcoat.2005.06.013","article-title":"Synthesis, Characterization and Development of High Performance Siloxane-Modified Epoxy Paints","volume":"54","author":"Ahmad","year":"2005","journal-title":"Prog. Org. Coat."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1016\/j.porgcoat.2017.10.014","article-title":"Characterization and Properties of Epoxy Resin (E-20) Modified with Silicone Intermediate RSN-6018","volume":"114","author":"Shen","year":"2018","journal-title":"Prog. Org. Coat."},{"key":"ref_27","first-page":"145","article-title":"Synthesis and Characterization of Hydroxyl-Terminated Polymethylphenylsiloxane Oligomers","volume":"28","author":"Zhang","year":"2014","journal-title":"Org. Silicon Mater."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"131585","DOI":"10.1016\/j.conbuildmat.2023.131585","article-title":"Effect of Organosilicon Modified Epoxy Resin on Slurry Viscosity and Mechanical Properties of Polyurethane Grouting Materials","volume":"387","author":"Wang","year":"2023","journal-title":"Constr. Build. Mater."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/S0167-5729(02)00077-8","article-title":"Dynamic Atomic Force Microscopy Methods","volume":"47","year":"2002","journal-title":"Surf. Sci. Rep."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"166","DOI":"10.1016\/j.ijadhadh.2018.03.006","article-title":"Properties of Phenol Formaldehyde Resin Modified with Silane Coupling Agent (KH550)","volume":"84","author":"Wei","year":"2018","journal-title":"Int. J. Adhes. Adhes."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"105828","DOI":"10.1016\/j.reactfunctpolym.2024.105828","article-title":"The Synthesis of an Epoxy-Terminated Hyperbranched Polysiloxane Toughener and Its Application at Low Temperature","volume":"195","author":"Pan","year":"2024","journal-title":"React. Funct. Polym."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1471","DOI":"10.1016\/j.polymdegradstab.2005.10.005","article-title":"Thermal Degradation Behaviors of Some Branched and Linear Polysiloxanes","volume":"91","author":"Zhou","year":"2006","journal-title":"Polym. Degrad. Stab."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.tca.2012.11.010","article-title":"Thermal Degradation and Flammability of Novel Organic\/Inorganic Epoxy Hybrids Containing Organophosphorus-Modified Oligosiloxane","volume":"552","author":"Qian","year":"2013","journal-title":"Thermochim. Acta"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/j.polymdegradstab.2016.09.029","article-title":"Thermal Degradation Mechanism and Flame Retardancy of MQ Silicone\/Epoxy Resin Composites","volume":"134","author":"Jia","year":"2016","journal-title":"Polym. Degrad. 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