| 초록 |
A geopolymer, consists of Si-O-Al covalent bonds in a polymeric network, has a simple manufacturing process, excellent performance and less CO2 generation, compared to traditional cement. In particular, with the benefit of low curing temperature and fast curing, the geopolymers can be used for practical on-site applications. In this study, we have investigated optimal composition designed for fast- and low-temperature curing geopolymer with additives including Ca(OH)2, fumed silica, and chopped carbon fiber. A wide range of multivariate was systematically investigated via design of experiment. As a result, we developed a geopolymer composition with a flexural strength of 27.83 MPa and compressive strength of 54.22 MPa. Furthermore, the curing temperature and time are 20°C and 1 week (typical values in literature are 40°C and 1~4 weeks), while having rather high flexural and compressive strength than literature values. In addition, we have elucidated how the superior strength can be achieved while it being cured at low temperature for short time. It was discovered that the fumed silica impedes the growth of Ca compound; it balances two different effects stemming from Ca compounds which are strength degradation and rapid curing. The developed geopolymer is expected to be widely used in refractory applications such as sealants and finishing materials. |
