Microstructure and Properties of C-S-H/PCE Nanocomposites

Abstract:

Different dosage of TPEG-polycarboxylate (PCE) copolymers were used to prepare the calcium-silicate hydrated (C-S-H)/PCE nanocomposites by precipitating C-S-H from Na₂SiO₃·9H₂O and Ca (NO₃)₂·4H₂O in the PCE solution. The composition and structure of the prepared C-S-H/PCE nanocomposites were characterized by XRD, SEM, FTIR methods, and the early strength of mortars was measured. The results show that structural investigation of the C-S-H/PCE nanocomposites via X-ray diffraction revealed a semi-crystalline composition, and the PCE polymers were adhered the surface of C-S-H particles in the composite. The preparation of C-S-H /PCE nanocomposites enhanced markedly the early strength of mortar, and when the dosage of PCE copolymers was up to 30%, the early strength enhancing effect was the highest, the early flexural strength increased up to 100%, and early compressive strength increased up to 120%. Therefore, C-S-H /PCE nanocomposites can improve the early strength of mortar effectively since it can lower the barrier of nucleation of the products, promote the nucleation and inhibit the growth of large grains effectively.

• Periodical: Materials Science Forum (Volume 898)
• Pages: 2089-2094
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.898.2089
• Online since: June 2017
• Authors: He Qing Shen*, Zi Ming Wang, Xiao Liu, Xiao Fan Pang, Long Xue
• Keywords: C-S-H, Early Strength, Nanocomposite, Polycarboxylate (PCE)

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