Facile preparation of cubic calcium carbonate nanoparticles with hydrophobic properties via a carbonation route

Hydrophobic Calcium Carbonate for Cement Surface

“…This clearly indicates that carbonation has taken place in the materials undertaken for this study. Solid state 13 C CP-MAS NMR also corroborates this and is discussed in the later section. Besides the peaks of SiO2 and CaCO3, few peaks at higher carbonation temperatures (60 and 90 °C) arise, which may be attributed to the association of organic molecule with the cement matrix to form calcium stearate.…”

“…Calcium stearate (50% excess Ca) were taken as reference material for comparing with the carbonated cement material. The solid state 13 C NMR spectras are presented in Figure 5. Figure 5a shows the NMR spectrum of pure calcium stearate.…”

“…The C1, C2, C3, C17, and C18 peaks are difficult to detect in the spectrum of cement block materials as compared to pure calcium stearate. Figure 5b shows the carbonation of cement block without any sodium sterate, the formation of 13 C peak arises due to the formation of CaCO3 and its chemical shift value is 169.12. This data clearly indicates that carbonation has taken place in our samples.…”

“…There are many reports on the synthesis of hydrophobic calcium carbonate via carbonation route [13]. Hydrophobic calcium carbonate leads to many industrial applications.…”

“…It is used as pigment, mortar, and abrasive and in paper and plastic as a filler [14]. Chen et al have reported carbonation of Ca(OH) 2 to synthesize cubic CaCO 3 using dodecanoic acid as modifier [13]. Several organic additives used for synthesizing hydrophobic CaCO 3 via carbonation of Ca(OH) 2 include oleic acid [15], octadecyl dihydrogen phosphate [16], sodium oleate [17], stearic acid [18], and dodecanoic acid [19].…”