Abstract
Lightweight geopolymers are well-suited for construction applications, including thermal and acoustic insulation panels and fire-resistant barriers. Their porous microstructure can be tailored by incorporating gas bubbles into the fresh ceramic mixture. Several factors—such as geopolymer composition, mixing and curing conditions, and the setting behavior of the paste—play a crucial role in bubble retention within the consolidated specimens. This study investigated the processing of porous metakaolin-based geopolymers prepared with the addition of 5, 7.5, and 10 wt.% of a preformed liquid foam stabilized with xanthan gum. The addition of 0.45 wt.% xanthan gum improved foam stability, ensuring uniform pore distribution and minimizing bubble collapse during processing. This approach enabled the fabrication of specimens with low densities (0.87–1.46 g/cm3) and high porosity (39.49%–64.78%), significant air permeability, and well-controlled microstructural characteristics, with average pore sizes varying from 99 to 137 µm. Based on the findings, the geopolymeric binder containing 7.5 wt.% foam demonstrated a balance of strength, low density, reduced water absorption, and engineered porosity, making it a promising candidate for sealing components or thermal insulation materials. The direct foaming method and processing conditions effectively enhanced the properties of porous geopolymers, highlighting their potential for advanced construction applications.
| Original language | English |
|---|---|
| Article number | e15137 |
| Journal | International Journal of Applied Ceramic Technology |
| Volume | 22 |
| Issue number | 4 |
| Early online date | 4 Apr 2025 |
| DOIs | |
| Publication status | Published - 1 Jul 2025 |
Acknowledgements
his study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001. This work was carried out with the support of Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq (Process 304005/2023-1). The authors thank Nouryon, Metacaulim do Brasil, and Camargo Química for supplying the raw materials used in this work. The authors also thank Prof. Dr. Oscar Peitl and LaMaV (Vitreous Materials Laboratory, DEMa-UFSCar) for the FTIR analyses performed in this study.Funding
This study was financed in part by the Coordena\u00E7\u00E3o de Aperfei\u00E7oamento de Pessoal de N\u00EDvel Superior\u2014Brasil (CAPES)\u2014Finance Code 001. This work was carried out with the support of Conselho Nacional de Desenvolvimento Cient\u00EDfico e Tecnol\u00F3gico, CNPq (Process 304005/2023-1). The authors thank Nouryon, Metacaulim do Brasil, and Camargo Qu\u00EDmica for supplying the raw materials used in this work. The authors also thank Prof. Dr. Oscar Peitl and LaMaV (Vitreous Materials Laboratory, DEMa-UFSCar) for the FTIR analyses performed in this study. The Article Processing Charge for the publication of this research was funded by the Coordena\u00E7\u00E1o de Aperfei\u00E7oamento de Pessoal de N\u00EDvel Superior - Brasil (CAPES) (ROR identifier: 00x0ma614). The Article Processing Charge for the publication of this research was funded by the Coordena\u00E7\u00E1o de Aperfei\u00E7oamento de Pessoal de N\u00EDvel Superior \u2010 Brasil (CAPES) (ROR identifier: 00x0ma614).
| Funders | Funder number |
|---|---|
| DEMa-UFSCar | |
| Vitreous Materials Laboratory | |
| Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior | |
| Conselho Nacional de Desenvolvimento Cientifico e Tecnologico | 304005/2023-1 |
| Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior | 00x0ma614 |
Keywords
- binder
- metakaolin
- microstructure
- porous geopolymer
- preformed foam
ASJC Scopus subject areas
- Ceramics and Composites
- Condensed Matter Physics
- Marketing
- Materials Chemistry