Study of the influential factors on the rheological behavior of adhesive mortar available in the market

Abstract

Rheology studies the deformation and flow of matter and seeks to describe the deformations of material depending on the time they are exposed to mechanical actions. This paper proposes to understand the behavior of fresh mortar adhesives in Squeeze Flow tests based on rheological characterization of different commercial compositions. In the tests, flow of material results from the application of a compressive load on the sample in the fresh state which causes displacement due to stresses generated during radial shear flow. We performed further physical characterizations of mortars and viscosity on material passing the through a sieve with a 0.075 mm sieve opening with the objective of basing the analysis of the results obtained from Squeeze Flow tests. It was observed that the mortars studied showed differences in rheological behavior, probably resulting from synergistic action of some of the composition parameters, especially the particle size distribution and particle morphology.

Low‐weight fractions of graphene and hydroxyapatite enhance mechanics in photocured methacrylate adhesives

“…Rheology results for the composites with G and HA additives are shown in Figure 6(a),(b). Viscosity decreases with increasing shear rate for all UDMA‐MMA composites enhanced with either G or HA, indicating thixotropic or non‐Newtonian behavior 43,44 . Viscosity increases with increasing G or HA concentration, which is expected in additive containing polymers 13,45,46 .…”

“…Viscosity decreases with increasing shear rate for all UDMA-MMA composites enhanced with either G or HA, indicating thixotropic or non-Newtonian behavior. 43,44 Viscosity increases with increasing G or HA concentration, which is expected in additive containing polymers. 13,45,46 The viscosity at a shear rate of 10 s −1 for the composites containing G ranges from 0.024 ± 0.001 to 0.043 ± 0.001 PaÁs, while the viscosity for composites containing HA ranges from 0.024 ± 0.001 to 0.074 ± 0.001 PaÁs.…”

Skin formation in adhesive mortars evaluated by MRI and interfacial rheology

“…Skin formation have an import role on adhesion, therefore, research and further developments should focus on improvement of techniques to its characterization. The wide surface area in which material is applied (substrate-mortar interface) and exposed to (air-mortar interface) before tile placement generates a great loss of water that not only has an intrinsic influence on the mortar's properties [10], but also affects skin formation. As the initial contact between fresh mortar and tile is the first step for the development of interfacial microstructure, for the adhesive properties between the materials, the comprehension of the rheological behavior at the air-mortar interface and its evolution with time and drying is of great importance for mortar producers and users.…”