Effect of Polysiloxanes on Roughness and Durability of Basalt Fibres⁻Reinforced Cement Mortar.

Danuta Barnat-Hunek,Grzegorz Łagód,Stanisław Fic,Monika Jarosz-Hadam

doi:10.3390/polym10040420

Danuta Barnat-Hunek, Grzegorz Łagód + Show 2 more

Open Access

https://doi.org/10.3390/polym10040420

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Abstract

The influence of roughness and the way it affects the adhesion properties and surface free energy (SFE) of polysiloxanes hydrophobised basalt fibres–reinforced cement mortars were determined in this article. The physical properties of mortars were investigated in the experimental part, which also explored the impact of hydrophobisation and basalt fibres (BF) addition on SFE, frost resistance, contact angle (CA), and roughness. A device capable of calculating all parameters was used to indicate the surface roughness and 3D topography. Prior to and after conducting surface and weight hydrophobisation, the contact angle of mortars was specified. Subsequently, it was used for carrying out SFE calculation by means of Neumann’s method, enabling us to characterize the adhesion properties and wettability of mortars. The research indicated that the surface roughness was substantially decreased, in turn raising the frost resistance. The corrosion resistance drops when the surface roughness, water absorption, and number of fibres in the mortar increase. The SEM images presenting the structure of polysiloxane coating and mortars were provided.

Highlights

The basalt fibre (BF), developed in Moscow Research Institute of Glass and Plastic in 1953–1954, is a technologically advanced fibre [1,2]
The mortars with the highest amount of BF are characterized by the greatest roughness, which is 30%–32% higher than Rmax of standard cement mortars
This work analyzed the physical properties as well as the microstructure characterizing the cement mortars with basalt fibres subjected to hydrophobisation

Summary

Introduction

Moiseev E.A. et al noted that the crystallization behavior and presence of iron oxide in the production of basalt fibres have an impact on the heat temperature stability [8,9]. The literature studies indicate that basalt fibres are employed in mortars in order to reinforce cement matrices, owing to their properties including high durability, better stability, improved toughness, and ability to resist repeated impact [4]. The basalt fibres in mortars improve the flexural and tensile strength, ductility, as well as cracking energy of cement materials. The professional literature indicates that a sensible addition of basalt fibres amounts to approximately 1–3% (w/w) of binder [4]. The addition of basalt fibres to the mortar reduces the drying shrinkage and greatly improves the abrasion resistance and the resistance to frost and alkali [10,11]. The content of fibres frequently increases the porosity and absorptivity, Polymers 2018, 10, 420; doi:10.3390/polym10040420 www.mdpi.com/journal/polymers

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