APPLICATION OF FTIR-SPECTROSCOPY TECHNIQUE IN CHARACTERIZING MOLECULAR STRUCTURE OF NATURAL POZZOLAN-BASED GEOPOLYMER CEMENT

geopolymer cement (inorganic polymeric binder) based on natural pozzolan are investigated. SiOof activator and total molar ratios of Nacomposition exhibiting the highest ۲۸-day compressive strength. Mixtures exhibiting the highest compressive strength were studied for their molecular structure using laboratory technique of Fourier transform infrared spectroscopy.Results obtained confirm that changes in chemical composition and curing condition can result in variations in degree of silicon substitution by aluminum in the second coordination sphere. Hydrothermal curing affects the molecular structure so that by increasing the hydrothermal curing temperatures, a lower degree of silicon substitution by aluminum in the second coordination sphere is observed. The molecular structure of the studied inorganic polymeric binde is composed of Si-O-Si chains bonded to Al-O and Si-O units creating two and three dimensional networks. In this paper, the effects of chemical composition and curing conditions on molecular structure of۲/Na۲O molar ratio۲O/Al۲O۳, and H۲O/Al۲O۳ were changed to determine the optimum chemical

کلیدواژه ها:

Geopolymer ، Natural Pozzolan ، Molecular structure