Adhesion is a physical-chemical parameter able to render innovations to Portland cement-based materials. However, this concept still lacks experimental evidence to underlie further developments in this subject. This work has demonstrated how distinct substances can impart different adhesion forces after evaluating the hydration degree and the mechanical strength of non-reactive cementitious materials. The substances capable of making tridimensional hydrogen bonds, such as water, for instance, were the most effective in providing cementitious samples with improved bending strength. It implies that water is not only important because of its role in cement hydration, but also because it develops adhesion between hydrated cementitious surfaces. More than speculating the fundamental understanding on adhesion in Portland cement-based materials, the present paper intends to stimulate thinking on how to take the benefits of the water confined between the hydrated cementitious surfaces as an in-built nanoadhesive, so far little explored, but at the same time so prone to yield high performance materials.
adhesion; hydrogen bond; mechanical properties; Portland cement
