For fabricating a material with light weight and effective thermal insulation, i prefer using Geofoam or EPS to compose with GPC for better load carrying Walls/Roof Panels with reduced thickness.

Thank you@Basil Ahamed

Dear Sophy,

the list of raw materials that you want to use isn’t enough to create geopolymer composite or geopolymer foam , that means mineral polymer (from geopolymer binder’s creation ) and lightweight due to air entrance agents or as suggested by Basil EPS (polystyrene can be used at different density depending on what kind of Lambda you want to obtain). Peroxide and aluminum powder can be useful to create gas and bubbles, but will be quite difficult to control the size of these bubbles so your “soufflé “ can fail if setting time isn’t so fast or if expansion is too strong (macro bubbles are very dangerous for stability) . In particular, Metakaolin and Fly ash (only low calcium, F class) can be used as useful geopolymer powder precursors but both have the limit of long setting time at room temperature so to maintain your foamed material you need heat curing . Please forgets to use steel fibers because are really very heavy (0,1g each usually) so completely useless for lightweight target. Biomass ash hasn’t the correct mineralogy to be used as precursor for Geopolymers and KOH , too strongly caustic and corrosive , can be used only to obtain alkali activation not for geopolymerization. There are better results using silicates realized in autoclave that are user friendly and less dangerous for your health. Try to consider to use some lightweight aggregates to reduce final density of hardened product , because lambda and thermal insulation are connected to the air content inside the material (more open porosity so more air , that has the best lambda of 0,026 , for obtaining more insulation and lower total lambda) .

Hoping to be useful for your project .

Kind regards

Alex Reggiani