PEG-assisted controlled precipitation of calcium hydroxide and calcium carbonate nanostructures for cement reinforcement

• DOI: 10.1016/j.matchemphys.2021.124865
• Publication Date: 2021-06-20T09:22:47Z
• Authors: Ilaha Hasanova; Ulviyya Hasanova; Eldar Gasimov; Fuad Rzayev; Elman Hajiyev; Goncha Eyvazova; Meherrem Shaliyev; Aytaj Mehdiyeva; Nushaba Aliyeva; Yusif Yusifov; Hikmat Ismayilov; Haji Vahid Akhund...; Zohrab Aghamaliyev; Sarvinaz Hajiyeva; Pervane Huseynova
• Keywords: 02 engineering and technology; 0210 nano-technology

Abstract Herein, we have developed simple, one-stage and cheap precipitation methods for synthesizing Ca(OH)2 and CaCO3 nanoparticles with average sizes of (75 ± 8)0.95 and (70 ± 10)0.95 nm, respectively. Both methods are based on CaCl2 precursor and cheap polyethylene glycol (PEG) surfactant. The influence of the precipitation conditions on the size and morphology of crystallites was studied, and the required conditions for the formation of anisotropic crystals of Ca(OH)2 and CaCO3 were identified. Preliminary studies showed that all concentrations of isotropic CaCO3 nanoparticles increased the flexural and compressive strength of 2-day cement by more than 50% and more than 30%, respectively. The best overall result was achieved with 0.06% of CaCO3 nanoparticles, which increased the compressive and flexural strength of 28-day cement by ≈ 9% and ≈12%, respectively. The compressive strength of all the samples with Ca(OH)2 nanoparticles at 2 days and 28 days increased by more than 20% and more than 5%, while the flexural strength of all 2-day cements increased by more than 25%.