What is alkali-activated binder?
Alkali-activated binders or geopolymer binders are hardened Page 2 compounds which acquire their strength and other properties by chemical reaction between an alkaline soluble source and aluminate-rich raw materials.
What is alkali activation technology?
Alkali-activation is a globally growing technology that involves the chemical reaction between a solid aluminosilicate precursor and an alkaline activator, at room temperatures, giving a hardened product (Shi et al. 2006).
Why alkali-activated materials AAM are not Geopolymers?
To sum up: Alkali-Activated Materials (AAM) are NOT Polymers, so they cannot be called Geo- Polymers. They belong to two very different and separate chemistry systems (a hydrate/precipitate that is a monomer or a dimer versus a true polymer).
Is Metakaolin a geopolymer?
Geopolymerization is a reaction of silicon (Si) and aluminum (Al) in natural source material such as metakaolin (MK) or in byproduct materials such as fly ash with alkali activators that leads to the formation of geopolymer binders [5,6].
What is activated material?
Alkali activated materials (AAMs) are binders, sometimes named geopolymers, that are produced through the reaction of an alkali source and aluminosilicates. The most commonly used alkali sources are sodium or potassium hydroxides and/or silicates, while aluminosilicates may include suitable raw materials and wastes.
What is meant by geopolymer?
Geopolymers are inorganic, typically ceramic, alumino-silicate forming long-range, covalently bonded, non-crystalline (amorphous) networks. Raw materials used in the synthesis of silicon-based polymers are mainly rock-forming minerals of geological origin, hence the name: geopolymer.
What is the difference between geopolymer concrete and alkali activated concrete?
Generally in the literature, the ligands with precursors based on alumina and silica are treated as geopolymers, while alkali activated cement are based on precursors rich in calcium.
How strong is geopolymer?
Hence this geopolymer could be categorised as structural concrete Class I (compressive strength more than 15 MPa) and structural and insulating concrete Class II (compressive strength between 3.5 and 15 MPa and thermal conductivity less than 0.75 W/m K) according to the RILEM (1983) classification.
Is geopolymer a ceramic?
Geopolymers are ceramic-like inorganic polymers pro- duced at low temperature, generally below 100 °C.