ITPN   24979
INSTITUTO DE TECNOLOGIA EN POLIMEROS Y NANOTECNOLOGIA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Effect on the Hydration of Aged Dry-mixed Cement Mortars
Autor/es:
EDGARDO F. IRASSAR; TERESA MARÍA PIQUE; JOHANN PLANK
Lugar:
Salta
Reunión:
Congreso; VII Congreso Internacional 21º Reunión Técnica "Ing. Nélida del Valle Castría"; 2016
Institución organizadora:
Asociación Argentina de Tecnología del Hormigón
Resumen:
Shelf-life stability of premixed cement mortars is affected by high temperatures and humidity. Inside the cement dry-mixed bags, cement is in contact with polymers, such as Ethylene Vinyl Acetate copolymer (EVA), presented as redispersible polymer powder. In this project rigorous climate conditions were simulated in a climate chamber to learn what happens inside these bags when subjected to high temperature and humidity. Cement mixed with EVA was aged and the prehydration was studied after 1 and 3 days of storage in the climate chamber. After aged the samples were mixed with water and the hydration was studied by means of in situ XRD, isothermal calorimetry and scanning electron microscopy. These tests showed that cement aged with EVA was less prehydrated than cement aged alone. The hydration of cement modified with EVA showed surprisingly poor ettringuite and portandite formation.