MoistureSensitivity

Moisture sensitivity refers to the degree to which a substance, component, or system responds to moisture in its environment. It covers physical, chemical, and functional changes caused by water absorption, high humidity, or condensation.

In materials science, moisture sensitivity is significant for polymers and composites that absorb water, leading to swelling, reduced stiffness, lowered glass transition temperature, or changes in dielectric and mechanical properties. Electronics and packaging often treat moisture sensitivity via Moisture Sensitivity Level (MSL), a rating that guides storage, handling, and reflow times after humidity exposure.

Measurement and testing: Methods include gravimetric sorption, dynamic vapor sorption, and moisture content determination (Karl Fischer titration). Data are interpreted with sorption isotherms to estimate equilibrium moisture content and diffusion coefficients. Thermal or mechanical testing under humidity assesses performance changes.

Mitigation and application: Control humidity, use moisture barriers, desiccants, surface coatings, and proper drying or conditioning processes. Material selection and design may reduce sensitivity by using hydrophobic polymers, crosslinking, or additives. Understanding moisture sensitivity is crucial in manufacturing, storage, and long-term reliability of products, as well as in agricultural contexts where seed germination and viability depend on moisture levels.