Geopolymers can be synthesized at low temperatures (25–80 °C) using an alkaline solution and an alumino-silicate material. Materials including amorphous silica, alumina, and alkali hydroxide (NaOH/KOH) are commonly used in the synthesis. For the synthesis of the binder, a variety of aluminosilicate materials can be employed. Metakaolin, rice husk ash, fly ash, and volcanic slag are among them.

fly ash

Thank you so much

Dear Hicham,

first you must know what is a Geopolymer because your question explains you don’t know correctly…

Geopolymerization isn’t Alkali Activation so there isn’t an activator. If I have to activate something it means this is the most important ingredient, the main actor of the process. But this is the case of Alkali Activation that produces unstable materials specially under water immersion, creates efflorescence due to migration of alkali to the surface and it’s still not possible to be industrialized. The geopolymerization reaction is promoted by the specific mineralogy and chemistry inside the precursor in powder (aluminosilicate with amorphous structure already super reactive) then the liquid is ONLY a reagent balanced on that precursor and can be an alkaline medium with user friendly molar ratio (not corrosive silicates) or an acidic medium with specific concentration (much more expensive than alkaline way), but necessary for Hi-Tech application like composites and organic polymer resin substitution.

Check at the site of Geopolymer Institute where Professor Davidovits coined the term of Geopolymer to explain the geological nature (minerals) connected to polymeric reaction that isn’t hydraulic like AAM (alkali activated materials), that drives all the properties of these materials.

Find all scientific papers for free on :

www.geopolymer.org

and you could also buy a copy of the book that is the holy bible of this technology (technical terms, suggestions and all informations you need are there. But it is very technical book you will need time to understand all things. It opened my mind completely.)

Best regards

Alex Reggiani

Better to use Sodium hydroxide with Sodium silicate as an activator. Try to make a one-part geopolymer instead of a two-part geopolymer.

Dear Isuru Batuwita, I think your answer is proper for Alkali Activated materials only.

Geopolymer materials are different and have proper mix design and industrially speaking aren‘t feasible as one component.

Regards

Dear Alex Reggiani,

I already have done the research for one-part geopolymer . It mainly has an activator and Precursor(Reactive Silicate and aluminate source). I have read many research papers to get an approach to that. Within that, they used different Precursors with alkaline as activators.

So could you please tell me what are the other activators than alkaline for Geopolymer?