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Geopolymers are new materials for fire- and heat-resistant coatings and adhesives, medicinal applications, high-temperature ceramics, new binders for fire-resistant fiber composites, toxic and radioactive waste encapsulation and new cements for concrete. The properties and uses of geopolymers are being explored in many scientific and industrial disciplines: modern inorganic chemistry, physical chemistry, colloid chemistry, mineralogy, geology, and in other types of engineering process technologies. Geopolymers are part of polymer science, chemistry and technology that forms one of the major areas of materials science. Polymers are either organic material, i.e. carbon-based, or inorganic polymer, for example silicon-based. The organic polymers comprise the classes of natural polymers (rubber, cellulose), synthetic organic polymers (textile fibers, plastics, films, elastomers, etc.) and natural biopolymers (biology, medicine, pharmacy). Raw materials used in the synthesis of silicon-based polymers are mainly rock-forming minerals of geological origin, hence the name: geopolymer. Joseph Davidovits coined the term in 1978[1] and created the non profit French scientific institution (Association Loi 1901) Institut Géopolymère (Geopolymer Institute).
According to T.F. Yen[2] geopolymers can be classified into two major groups: pure inorganic geopolymers and organic containing geopolymers, synthetic analogues of naturally occurring macromolecules. In the following presentation, a geopolymer is essentially a mineral chemical compound or mixture of compounds consisting of repeating units, for example silico-oxide (-Si-O-Si-O-), silico-aluminate (-Si-O-Al-O-), ferro-silico-aluminate (-Fe-O-Si-O-Al-O-) or alumino-phosphate (-Al-O-P-O-), created through a process of geopolymerization.[3] This mineral synthesis (geosynthesis) was first presented at an IUPAC symposium in 1976.[4] However, very
References: 2. Jump up ^ Kim, D.; Lai, H.T.; Chilingar, G.V.; Yen T.F. (2006), Geopolymer formation and its unique properties, Environ. Geol, 51[1], 103–111. 5. Jump up ^ Davidovits, J., (1991), Geopolymers: Inorganic Polymeric New Materials, J. Thermal Analysis, 37, 1633–1656 6 9. Jump up ^ Gluchovskij V.D.:"Gruntosilikaty" Gosstrojizdat Kiev 1959, Patent USSR 245 627 (1967), Patent USSR 449894 (Patent appl. 1958, granted 1974!). 14. Jump up ^ Peigang He, Dechang Jia , Meirong Wang, Yu Zhou, (2011) (Harbin Institute of Technology, Harbin, PR China:), Thermal evolution and crystallization kinetics of potassium-based geopolymer, Ceramics International, 37, 59–63. 15. Jump up ^ Feng, Dingwu; Provis, John L. and van Deventer, Jannie S. J. (2012) (University of Melbourne, Australia), Thermal Activation of Albite for the Synthesis of One-Part Mix Geopolymers, J. Am. Ceram. Soc., 95 [2] 565–572. 16. Jump up ^ Bell, Jonathan L.; Driemeyer, Patrick E. and Kriven, Waltraud M. (2009) (University of Illinois, USA), Formation of Ceramics from Metakaolin-Based Geopolymers. Part II: K-Based Geopolymer, J. Am. Ceram. Soc., 92 [3], 607-615. 19. ^ North, M.R. and Swaddle, T.W. (2000). Kinetics of Silicate Exchange in Alkaline Aluminosilicate Solutions, Inorg. Chem., 39, 2661–2665. 20 21. Jump up ^ Duxson, P.; Fernández-Jiménez, A.; Provis, J.l.; Lukey, G.C; Palomo, A. and Van Deventer, J.S.J., (2007), Geopolymer technology: the current state of the art, J. Mat. Sci., 42 (9) 2917–2933. 22 29. Jump up ^ see the updates in the Keynotes State of Geopolymer R&D, 2009, 2010, 2011, and 2012 at http://www.geopolymer.org/camp) 30 31. Jump up ^ Lyon, R.E.; Foden, A.J.; Balaguru, P.N.; Davidovits, J. and Davidovics, M. (1997), Properties of Geopolymer Matrix-Carbon Fiber Composites, Fire and Materials, 21, 67–73. 32 Jump up ^ Silverstrim, T.; Rostami, H.; Larralde, J.C and Samadi-Maybodi, A. (1997), Fly ash cementitious material and method of making a product, US Patent 5,601,643. Jump up ^ Van Jaarsveld, J.G.S., van Deventer, J.S.J Jump up ^ Túnyi, I. and El-hemaly, I. A. (2012), Paleomagnetic investigation of the great egyptian pyramids, Europhysics News 43/6, 28-31. Jump up ^ As part of the European research project GEOCISTEM [33], Davidovits J Geopolymer Chemistry and Applications, Joseph Davidovits, Institut Géopolymère, Saint-Quentin, France, 2008, ISBN 9782951482050 (3rd ed., 2011). In Chinese: National Defense Industry Press, Beijing, ISBN 9787118074215, 2012. Geopolymers Structure, processing, properties and industrial applications, John L. Provis and Jannie S. J. van Deventer, Woodhead Publishing, 2009, ISBN 9781845694494.