Dampsubstansen

Dampsubstansen is a term used in material science and related fields to describe substances that interact with water vapor in their environment. It is not a single material, but a state describing the presence and movement of moisture within porous or hygroscopic substances. The concept emphasizes the dynamic exchange of water between a material and surrounding air, influencing its properties and behavior.

Moisture content (MC) and equilibrium moisture content (EMC) are central quantities. MC is usually expressed as the mass of water per unit dry mass; EMC depends on relative humidity and temperature. Sorption isotherms characterize how MC changes with humidity, and hysteresis describes differences between absorption and desorption paths. Water transport is often described by diffusion or capillary rise within the damp substansen.

Dampsubstansen appears across many domains, including construction materials such as wood and concrete, soils, textiles, and food products. Excess moisture can cause swelling, shrinkage, reduced mechanical strength, and altered thermal or acoustic properties. It also creates conditions favorable to mold growth and corrosion in metals.

Measurement and analysis involve gravimetric methods (drying to constant mass), moisture analyzers, and sorption instruments; Karl Fischer titration is used for precise water content in some substances; infrared and thermal methods help map moisture distribution.

Management focuses on controlling humidity and moisture sources through ventilation, dehumidification, sealing barriers, and drainage, as well as selecting materials with appropriate moisture tolerance.

See also hygroscopicity, moisture diffusion, sorption isotherm.