Effect of temperature and activator molar of Na2O to SiO2 in the process of synthesis and microstructure of cement geopolymer

Journal of Advanced Materials and Processing

مقاله 2، دوره 1، شماره 3، مهر 2013، صفحه 3-10   

نوع مقاله: Research Paper

نویسندگان

M Asadi^{* 1}؛ A Nemati²؛ R Naghizadeh³؛ K Arzani⁴؛ J Fahim⁵

¹Ph.D. student, Department of Materials Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

²Department of Materials Engineering, University of Sharif Technology, Tehran, Iran

³School of Metallurgy and Materials Engineering, Iran University of Science and Technology (IUST), Tehran, Iran

⁴Department of Materials Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran

⁵Ph.D. student, Department of Materials Engineering, Najafabad Branch, Islamic Azad University,Isfahan,Iran

چکیده

Inorganic polymers were synthesized from dehydroxylated aluminosilicate clay (metakaolinite) condensed with sodium silicate in a highly alkaline environment. The thermal treatment of aluminosilicate materials causes changes in their structure with an increase in the amorphous phase. For that kind of structural change XRD analysis is not appropriate, so those changes are currently assessed by infrared emission spectra analysis (FTIR). The most characteristic FTIR band in the geopolymeric systems appears in the wavenumbers region 990-1090cm^-1 and is attributed to the asymmetric stretching vibration of T-O-Si, where T denotes Si or Al. The shift of this peak towards lower wavenumbers indicates the dissolution of the amorphous aluminosilicate phase of the raw material and the formation of a new amorphous gel in which the backbone consists of polymeric chains with smaller length in relation to the ones of the raw material. The SEM result showed that geopolymer paste was formed from quartz remaining particles and gel. The remaining particle size was reduced by increase of the curing temperature and Na₂O/SiO₂ molar ratio. The results indicated that samples with adequate strength are created compact and crack-free areas.

کلیدواژه‌ها

Geopolymer cement؛ Metakaolinite؛ Compressive strength؛ Microstructure؛ Infrared spectroscopy؛ Scanning electron microscopy