Volume 40, Issue 6 (November 2012)

    Examining Polymerization of Kaolinitic Concrete Using Scanning Electron Microscopy and Raman Spectroscopy

    (Received 26 December 2011; accepted 24 March 2012)

    Published Online: 2012

    CODEN: JTEOAD

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    Abstract

    Geopolymers are environmentally friendly substitutes for Portland cement; in many applications, geopolymers not only reduce greenhouse gas emissions but also are recyclable. The hardening mechanism of geopolymer polymerization differs from that of ordinary Portland cement. In the present research, two methods are used to evaluate the microstructure of this inorganic material. In the first method, complete polymerization was observed by means of scanning electron microscopy (SEM) to reveal the foundations of strength establishment. The SEM results show that the synthesized geopolymer maintained a layer structure of metakaolinite particulates. Therefore, it was thought that the geopolymeric reaction mainly occurred at the surface of microflakes of metakaolinite particulates. In order to further investigate the polymerization process of the material, two Raman spectrum frequency ranges—875 nm and 325 nm—were used in the study because of their capability to characterize the mineral/hydrated phases under a thick post-treatment layer. Also, in order to facilitate quality control of the production and explore the extreme compressive strengths of metakaolin cement, the polymerization mechanism and microstructures of the products were monitored step by step using Raman spectroscopy. The lessons learned in the research program can be used to advance the research methodology needed for further investigation of the strength enhancement of the geopolymer.


    Author Information:

    Kuo, Chin-kun
    Associate Professor, Dept. of Sports, Health, and Leisure, Dept. of Architectural Engineering, Vung-Ta Institute of Technology & Commerce, Pingtung County,

    Wang, Edward H.
    Associate Professor, Dept. of Civil Engineering and Environmental Informatics, Minghsin Univ. of Science and Technology, Hsin-Chu County,

    Hwang, Chao-Lung
    Professor, Dept. of Construction Engineering, National Taiwan Univ. of Science and Technology, Taipei,


    Stock #: JTE104641

    ISSN: 0090-3973

    DOI: 10.1520/JTE104641

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    Author
    Title Examining Polymerization of Kaolinitic Concrete Using Scanning Electron Microscopy and Raman Spectroscopy
    Symposium , 0000-00-00
    Committee C01