Water Absorption 24 Hour/Equilibrium ASTM D570

Scope:
Water absorption is used to determine the amount of water absorbed under specified conditions. Factors affecting water absorption include: type of plastic, additives used, temperature and length of exposure. The data sheds light on the performance of the materials in water or humid environments.

Test Procedure:
For the water absorption test, the specimens are dried in an oven for a specified time and temperature and then placed in a desiccator to cool. Immediately upon cooling the specimens are weighed. The material is then emerged in water at agreed upon conditions, often 23°C for 24 hours or until equilibrium. Specimens are removed, patted dry with a lint free cloth, and weighed.

Specimen size:
Two inch diameter disks, 0.125" or 0.250" thick.

Data:
Water absorption is expressed as increase in weight percent.
Percent Water Absorption = [(Wet weight - Dry weight)/ Dry weight] x 100

Equipment Used:
Mettler balance

**Please note that this test description is intentionally generic in nature and aimed at providing a descriptive summary to enhance test understanding. Standards can be obtained from appropriate standard authorities.