Surface Modification of Lightweight Mortars by Nanopolymers to Improve Their Water-Repellency and Durability

Małgorzata Szafraniec,Małgorzata Grzegorczyk-Frańczak,Danuta Barnat-Hunek,Maciej Trochonowicz

doi:10.3390/ma13061350

Małgorzata Szafraniec, Małgorzata Grzegorczyk-Frańczak + Show 2 more

Open Access

https://doi.org/10.3390/ma13061350

Copy DOI

Journal: Materials	Publication Date: Mar 17, 2020
Citations: 13	License type: CC BY 4.0

Affiliation: Lublin University of Technology

Abstract

The paper explores the possibility of covering the mortar with the lightweight aggregate by the nanopolymer silane and siloxane as surface hydrophobisation. The investigation involved the mortars with two types of hydrophobic agents diluted with water in a ratio of 1:4 and 1:8. Mortar wetting properties were determined by measuring the absorbability, water vapor diffusion, contact angle (CA) and surface free energy (SFE) of their structure. Surface micro-roughness and 2D topography were evaluated. Scanning electron microscopy (SEM) has shown the microstructure and distribution of pores in mortars. The reduction in absorbency after the first day of testing by 87% was shown. An improvement in frost resistance after 25 cycles by 97% and an 18-fold decrease in weight loss after the sulphate crystallization test were observed. The hydrophobic coating reduces the SFE of mortars and increases the CA. In the case of using silanes, a 9-fold increase CA was observed.

Highlights

Over the last few years, researchers have been looking for more effective and ecological ways to protect building structures from a reduction in their durability
The best results were obtained on samples A1.4, with higher concentrations of water-repellent preparations
The analysis showed that the higher the roughness as well as the higher the weight loss after the frost test, the higher the weight loss after the salt test

Summary

Introduction

Over the last few years, researchers have been looking for more effective and ecological ways to protect building structures from a reduction in their durability. They try to modify the properties of building materials to make them more efficient and sustainable. Achieving long durability of building materials will contribute to the reduction of building waste production. In line with the global trends of energy-efficient construction, conventional mortars can be replaced by lightweight alternatives. As shown in Reference [1], the addition of wood waste positively influenced the improvement of some properties of mortars

Methods

Results

Conclusion