Fly ash-based geopolymer with kappa-carrageenan biopolymer

This chapter for the first time investigates the enhancement of fly ash-based geopolymer with kappa-carrageenan (KC), a seaweed extract. Mechanical tests were conducted to study the improvement of strength and prepeak toughness, and scanning electron microscopy and Fourier transform infrared spectroscopy were employed to study the microstructural and chemical evolution when different amounts of KC were incorporated in the fly ash-based geopolymer paste specimens. The results indicate that when the appropriate amount of KC is incorporated, the strength and prepeak toughness of the geopolymer increases substantially due to the hydrogen bonds and the more condensed geopolymer structure.