Journal of Thermal Analysis and Calorimetry

, Volume 126, Issue 3, pp 1417–1426 | Cite as

Influence of expandable graphite on flame retardancy and mechanical properties of organic–inorganic hybrid material based on sodium silicate and polyisocyanate

  • Jia-Ji Cheng
  • Fu-Bao Zhou


Influence of expandable graphite on flame retardancy and mechanical properties of organic–inorganic hybrid material based on sodium silicate and polyisocyanate has been investigated. The results of mechanical measurement show that adding expandable graphite decreases the maximum of the compressive strength from 5.98 to 1.49 MPa. The thermal property is evaluated by thermal conductivity test, thermogravimetric analysis. The results indicate that adding the expandable graphite increases thermal conductivity of composite and lowers maximum heat release rate. The material with expandable graphite has better flame retardancy than original material with an obvious decrease in heat release rate, fire spread and thermal decomposition rate. What is more, intumescent graphite has the obvious effect to suppress flame and prevent the composite from fire. Scanning electron microscope shows that many large particles and gaps appear after compression deformation.


Expandable graphite Hybrid material Flame retardancy Mechanical properties Thermal properties 



This work was supported by the State Key Laboratory of Coal Resources and Safe Mining, CUMT (SKLCRSM12X04), the Program for Changjiang Scholars and Innovative Research Team in University (IRT13098); the Fundamental Research Funds for the Central Universities (2014XT02). This work is also a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions and the First Outstanding Youth by the Organisation Department of the CPC Central Committee.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2016

Authors and Affiliations

  1. 1.State Key Laboratory of Coal Resources and Safe MiningChina University of Mining and TechnologyXuzhouPeople’s Republic of China
  2. 2.Key Laboratory of Gas and Fire Control for Coal MinesXuzhouPeople’s Republic of China
  3. 3.School of Safety EngineeringChina University of Mining and TechnologyXuzhouPeople’s Republic of China
  4. 4.College of Engineering and Computer ScienceAustralian National UniversityActonAustralia

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