Study of the coating gypsum waterproofing through the synthesis of the hydrophobic gypsum/silicone composite

Materia

article

Thainá Kelly dos Santos Silva¹  Andréa de Vasconcelos Ferraz¹  Débora Santos Carvalho dos Anjos² 

[1] Universidade Federal do Vale do São Francisco;Instituto Federal de Educação

关键词: Gypsum;    Silicone;    Composite;    Chloroform;    Coating;   

DOI  :  10.1590/1517-7076-RMAT-2022-0173

学科分类：工程和技术（综合）

来源: Universidade Federal do Rio de Janeiro * Coordenacao dos Programas de Pos-Graduacao de Engenharia

【 摘 要 】

Gypsum has conquered, over time, more and more space in the area of civil construction. Although the advances obtained in the use of gypsum, this material still has limitations, including water absorption due to its hydrophilic character, which limits its application in external ambience. The purpose of reducing water absorption, expanding its application in external coatings, this work aims at the incorporation of the silicone polymer (hydrophobic character) to the gypsum matrix. Therefore, the gypsum-silicone composite was synthesized, according to the norm NBR 12128 (2016). A water/gypsum ratio of 0.7 was used and the following parameters were varied, based on a factorial planning 22: (1) silicone content: (−) 1% and (+) 5% (silicone/gypsum) and (2) chloroform content: (−) 0% and (+) 12%. The materials obtained were characterized by scanning electron microscope (SEM), infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal analyzers and Raman spectrometers. The mechanical resistance to compression, the waterproofing time and the setting time were also determined. The incorporation of silicone gave the gypsum a reduction in water absorption and retardation in setting time. When adding the silicone to the plaster, there was no change in the compressive strength, however, when adding silicone with chloroform, there was a reduction of 1MPa compared to gypsum paste. The gypsum-silicone composite has potential application in coatings, promoting a reduction in water absorption.

【 授权许可】

CC BY