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Functional Properties of SAP-Based Humidity Control Plasters
Jan Fořt1, Magdaléna Doleželová1, Václav Kočí1
1Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, 16629 Prague, Czech Republic.
Polymers
|July 24, 2021
Summary
Superabsorbent polymers (SAPs) in lime-cement plasters enhance indoor humidity control. Adding 1 wt.% SAP offers a balance between moisture buffering and material strength for improved building microclimates.
Area of Science:
- Materials Science
- Building Physics
- Construction Engineering
Background:
- Improving indoor relative humidity is crucial for occupant comfort and building durability.
- Passive methods for humidity control are sought after to reduce energy consumption.
- Materials with high moisture storage capacity offer a promising solution for passive humidity regulation.
Purpose of the Study:
- To investigate the effect of superabsorbent polymers (SAPs) on the properties of lime-cement plasters.
- To analyze the mechanical, hygric, and thermal characteristics of SAP-modified plasters in relation to their microstructure.
- To determine optimal SAP dosages for enhanced passive humidity control in buildings.
Main Methods:
- Preparation of lime-cement plasters with three different types of SAPs at varying dosages.
- Experimental analysis of mechanical, hygric, and thermal properties.
- Microstructural characterization of the developed plaster composites.
Main Results:
- SAP incorporation significantly influences the functional properties of the plasters.
- A 1.5% SAP dosage can improve moisture buffering by up to 2.5 times.
- A 1 wt.% SAP dosage represents a compromise between moisture storage and mechanical integrity.
Conclusions:
- SAP-modified lime-cement plasters demonstrate enhanced passive humidity control capabilities.
- The study provides data for computational models to assess building interior microclimates.
- Optimized plasters can contribute to more stable and comfortable indoor environments.
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