A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Two-phase geopolymerization of kaolinite-based geopolymers
Abstract The effect of immersion in alkali solution as a second-phase geopolymerization of kaolinite-based geopolymers on their properties was investigated in this study. The aim of this work was to improve the geopolymer properties by increasing both its resistance to water absorption and mechanical performance. It was found that immersion in alkali solution as a second-phase geopolymerization – or a secondary treatment – at 80°C for 1h resulted in a high gain in compressive strength, and formation of secondary geopolymer gel. A dense stable layer, with several micrometers depth, was formed on the surface of kaolinite-based geopolymer without causing swelling or shrinkage. These surface and microstructural modifications led to reduction of water absorption and thus induced high durability. As a result of second-phase geopolymerization, the produced geopolymers exhibited an increase in compressive strength from 46MPa to 59MPa, and from 22MPa to 27MPa after drying and water immersion, respectively. The water absorption of the geopolymers decreased from 10% (w/w) to 4% (w/w), and the overall shrinkage after curing decreased from 0.18% to 0.01%.
Highlights Two-phase geopolymerization is introduced and investigated in this study. A dense stable surface layer of secondary geopolymer gel was formed. The secondary treatment led to increase in strength and resistance to absorption. The secondary treatment for long period causes high loss in mechanical performance.
Two-phase geopolymerization of kaolinite-based geopolymers
Abstract The effect of immersion in alkali solution as a second-phase geopolymerization of kaolinite-based geopolymers on their properties was investigated in this study. The aim of this work was to improve the geopolymer properties by increasing both its resistance to water absorption and mechanical performance. It was found that immersion in alkali solution as a second-phase geopolymerization – or a secondary treatment – at 80°C for 1h resulted in a high gain in compressive strength, and formation of secondary geopolymer gel. A dense stable layer, with several micrometers depth, was formed on the surface of kaolinite-based geopolymer without causing swelling or shrinkage. These surface and microstructural modifications led to reduction of water absorption and thus induced high durability. As a result of second-phase geopolymerization, the produced geopolymers exhibited an increase in compressive strength from 46MPa to 59MPa, and from 22MPa to 27MPa after drying and water immersion, respectively. The water absorption of the geopolymers decreased from 10% (w/w) to 4% (w/w), and the overall shrinkage after curing decreased from 0.18% to 0.01%.
Highlights Two-phase geopolymerization is introduced and investigated in this study. A dense stable surface layer of secondary geopolymer gel was formed. The secondary treatment led to increase in strength and resistance to absorption. The secondary treatment for long period causes high loss in mechanical performance.
Two-phase geopolymerization of kaolinite-based geopolymers
Alshaaer, Mazen (author)
Applied Clay Science ; 86 ; 162-168
2013-10-05
7 pages
Article (Journal)
Electronic Resource
English
Two-phase geopolymerization of kaolinite-based geopolymers
| Online Contents | 2013
Effect of curing temperature on geopolymerization of metakaolin-based geopolymers
| Online Contents | 2014