Inorganic–organic hybrid geopolymers: evolution of molecular and pore structure, and its effect on mechanical and fire-retardant properties

IF 3.4 3区 工程技术 Q2 CONSTRUCTION & BUILDING TECHNOLOGY Materials and Structures Pub Date : 2024-11-06 DOI:10.1617/s11527-024-02501-z
Rashmi Singla, T. Mishra, T. C. Alex, Sanjay Kumar
{"title":"Inorganic–organic hybrid geopolymers: evolution of molecular and pore structure, and its effect on mechanical and fire-retardant properties","authors":"Rashmi Singla,&nbsp;T. Mishra,&nbsp;T. C. Alex,&nbsp;Sanjay Kumar","doi":"10.1617/s11527-024-02501-z","DOIUrl":null,"url":null,"abstract":"<div><p>In order to overcome the brittle behavior of conventional geopolymers, of late, a paradigm shift towards development of hybrid geopolymers has commenced. This study describes hybrids synthesized by co-milling metakaolin and solid organics (epoxy resin: diglycidyl ether of bisphenol A and hardener: dicyandiamide) followed by alkali activation. The developed hybrid geopolymers exhibit enhanced mechanical and physical properties. Physical and mechanical properties of such hybrids depend on the extent of molecular-level interactions and microstructural evolution during geopolymerisation. Evolution of molecular structure from precursor stage (co-milled samples) to hybrid geopolymers is studied using transmission electron microscopy (TEM) and <sup>27</sup>Al, <sup>13</sup>C, <sup>29</sup>Si solid-state nuclear magnetic resonance (NMR) spectroscopy. NMR and TEM analyses of the hybrid geopolymers illustrate the formation of Si–O–C bonds and uniform C distribution (with no phase separation); this confirms inorganic–organic chemical interactions during geopolymerisation. Detailed assessment of pore characteristics using TEM, mercury intrusion porosimeter, and Brunauer–Emmett–Teller reveal formation of a dense gel (with reduced pore size and pore volume) in hybrid geopolymer vis-à-vis MK-based inorganic geopolymer. The implication of such microstructural features on mechanical and physical properties is discussed. Lastly, the suitability of developed hybrids as fire-retardant materials used in mass transit applications is highlighted.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"57 10","pages":""},"PeriodicalIF":3.4000,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Materials and Structures","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1617/s11527-024-02501-z","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0

Abstract

In order to overcome the brittle behavior of conventional geopolymers, of late, a paradigm shift towards development of hybrid geopolymers has commenced. This study describes hybrids synthesized by co-milling metakaolin and solid organics (epoxy resin: diglycidyl ether of bisphenol A and hardener: dicyandiamide) followed by alkali activation. The developed hybrid geopolymers exhibit enhanced mechanical and physical properties. Physical and mechanical properties of such hybrids depend on the extent of molecular-level interactions and microstructural evolution during geopolymerisation. Evolution of molecular structure from precursor stage (co-milled samples) to hybrid geopolymers is studied using transmission electron microscopy (TEM) and 27Al, 13C, 29Si solid-state nuclear magnetic resonance (NMR) spectroscopy. NMR and TEM analyses of the hybrid geopolymers illustrate the formation of Si–O–C bonds and uniform C distribution (with no phase separation); this confirms inorganic–organic chemical interactions during geopolymerisation. Detailed assessment of pore characteristics using TEM, mercury intrusion porosimeter, and Brunauer–Emmett–Teller reveal formation of a dense gel (with reduced pore size and pore volume) in hybrid geopolymer vis-à-vis MK-based inorganic geopolymer. The implication of such microstructural features on mechanical and physical properties is discussed. Lastly, the suitability of developed hybrids as fire-retardant materials used in mass transit applications is highlighted.

查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
无机-有机杂化土工聚合物:分子和孔隙结构的演变及其对机械和阻燃性能的影响
为了克服传统土工聚合物的脆性,近来开始转向开发混合土工聚合物。本研究介绍了通过共同研磨偏高岭土和固体有机物(环氧树脂:双酚 A 的二缩水甘油醚和固化剂:双氰胺),然后进行碱活化合成的混合土工聚合物。所开发的混合土工聚合物具有更强的机械和物理特性。这种混合聚合物的物理和机械性能取决于土工聚合过程中分子间相互作用的程度和微观结构的演变。使用透射电子显微镜(TEM)和 27Al、13C、29Si 固态核磁共振(NMR)光谱研究了从前驱体阶段(共磨样品)到混合土工聚合物的分子结构演变。对混合土工聚合物的核磁共振和透射电子显微镜分析表明,Si-O-C 键的形成和均匀的 C 分布(无相分离)证实了土工聚合物化过程中无机-有机化学相互作用。使用 TEM、汞侵入孔隙度计和布鲁瑙尔-艾美特-泰勒法对孔隙特征进行的详细评估显示,与基于 MK 的无机土工聚合物相比,混合土工聚合物形成了致密凝胶(孔径和孔隙体积减小)。本文讨论了这种微观结构特征对机械和物理特性的影响。最后,还强调了所开发的混合材料作为阻燃材料在公共交通应用中的适用性。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 去求助
来源期刊
Materials and Structures
Materials and Structures 工程技术-材料科学:综合
CiteScore
6.40
自引率
7.90%
发文量
222
审稿时长
5.9 months
期刊介绍: Materials and Structures, the flagship publication of the International Union of Laboratories and Experts in Construction Materials, Systems and Structures (RILEM), provides a unique international and interdisciplinary forum for new research findings on the performance of construction materials. A leader in cutting-edge research, the journal is dedicated to the publication of high quality papers examining the fundamental properties of building materials, their characterization and processing techniques, modeling, standardization of test methods, and the application of research results in building and civil engineering. Materials and Structures also publishes comprehensive reports prepared by the RILEM’s technical committees.
期刊最新文献
Enhancing adhesion of carbon-glass hybrid fibre-reinforced polymer tubes to seawater sea sand concrete through surface sand coating Effect of coarse recycled aggregate with embedded fibres on the mechanical properties and microstructure of polypropylene fibre-reinforced concrete Effect of emulsifier type on the properties of cement asphalt mortar for non-ballast slab tracks Effect of sulfate attack on geopolymer mortars at early ages of exposure Development and validation of an innovative Hybrid Laminate Material for the blast and fire protection of structures
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1