TY - JOUR

T1 - Influence of the molar ratios CaO/SiO2 contained in the sustainable microcomposites on the mechanical and microstructural properties of (Ca, Na)-poly(sialate-siloxo) networks

AU - T.Mabah, D. E.

AU - Fotio, D.

AU - Rüscher, Claus H.

AU - Authority, E.

AU - Bignozzi, M. C.

AU - Leonelli, C.

AU - Tchakouté, Hervé K.

N1 - Funding information: Hervé Tchakouté Kouamo gratefully acknowledges the Alexander von Humboldt Foundation for financially support this work under the grant N° KAM/1155741 GFHERMES-P . The authors would like to thank Mr Valerie Petrov for SEM observations.

PY - 2019/12/1

Y1 - 2019/12/1

N2 - The sustainable microcomposites with different molar ratios CaO/SiO2 such as 0, 0.4, 0.6, 0.8, 1.0 and 1.2 were prepared using calcined brown chicken eggshell, rice husk ash and distilled water. 10 wt% of each microcomposite was used to substitute metakaolin and the obtained calcium aluminosilicate materials were used for investigating the effects of the molar ratios CaO/SiO2 in the microcomposites on the physical, mechanical and microstructural properties of (Ca, Na)-poly (sialate-siloxo) networks. Commercial sodium waterglass and sodium waterglass from rice husk ash with a molar ratio SiO2/Na2O kept constant at 1.6 were used as chemical ingredients. Each (Ca, Na)-poly (sialate-siloxo) network was obtained by mixing each calcium aluminosilicate material with each hardener. The final products were characterized by infrared spectroscopy and X-ray diffractometry. The determination of the apparent density, compressive strength and scanning electron microscopy analysis were done. The results show that the compressive strength values of geopolymer cements using hardener from rice husk ash and microcomposites containing the molar ratios CaO/SiO2 equal to 0, 0.4, 0.6, 0.8, 1.0 and 1.2 are 64.01, 67.97, 66.15, 65.09, 60.73 and 49.40 MPa, respectively. Whereas, those from commercial sodium waterglass are 64.75, 69.03, 64.64, 56.73, 36.47 and 28.30 MPa, respectively. It was found that the most convenient molar ratio CaO/SiO2 in the structure of microcomposite required for producing (Ca, Na)-poly (sialate-siloxo) networks with higher mechanical properties is around 0.4.

AB - The sustainable microcomposites with different molar ratios CaO/SiO2 such as 0, 0.4, 0.6, 0.8, 1.0 and 1.2 were prepared using calcined brown chicken eggshell, rice husk ash and distilled water. 10 wt% of each microcomposite was used to substitute metakaolin and the obtained calcium aluminosilicate materials were used for investigating the effects of the molar ratios CaO/SiO2 in the microcomposites on the physical, mechanical and microstructural properties of (Ca, Na)-poly (sialate-siloxo) networks. Commercial sodium waterglass and sodium waterglass from rice husk ash with a molar ratio SiO2/Na2O kept constant at 1.6 were used as chemical ingredients. Each (Ca, Na)-poly (sialate-siloxo) network was obtained by mixing each calcium aluminosilicate material with each hardener. The final products were characterized by infrared spectroscopy and X-ray diffractometry. The determination of the apparent density, compressive strength and scanning electron microscopy analysis were done. The results show that the compressive strength values of geopolymer cements using hardener from rice husk ash and microcomposites containing the molar ratios CaO/SiO2 equal to 0, 0.4, 0.6, 0.8, 1.0 and 1.2 are 64.01, 67.97, 66.15, 65.09, 60.73 and 49.40 MPa, respectively. Whereas, those from commercial sodium waterglass are 64.75, 69.03, 64.64, 56.73, 36.47 and 28.30 MPa, respectively. It was found that the most convenient molar ratio CaO/SiO2 in the structure of microcomposite required for producing (Ca, Na)-poly (sialate-siloxo) networks with higher mechanical properties is around 0.4.

KW - (Ca, Na)-poly(sialate-siloxo) networks

KW - Compressive strength

KW - Metakaolin

KW - Microcomposites

KW - Sodium waterglass

UR - http://www.scopus.com/inward/record.url?scp=85069934232&partnerID=8YFLogxK

U2 - 10.1016/j.matchemphys.2019.121928

DO - 10.1016/j.matchemphys.2019.121928

M3 - Article

AN - SCOPUS:85069934232

VL - 238

JO - Materials chemistry and physics

JF - Materials chemistry and physics

SN - 0254-0584

M1 - 121928

ER -