General trend for moisture regain: Natural fibers (especially wool and cotton)>Regenerated fibers (rayon)>Synthetics (nylon>acrylic>polyester>polypropylene). Higher moisture regain generally means better comfort (breathability) but also can mean slower drying.
Step 1: Understanding Moisture Regain: Moisture regain is the amount of moisture a fiber can absorb from the air at standard conditions (typically 65% relative humidity and 70°F), expressed as a percentage of the fiber's dry weight. It's related to the fiber's chemical structure and how easily it forms hydrogen bonds with water.
Step 2: Approximate Moisture Regain Values:
Wool: ~13-18% (very high)
Cotton: ~8.5%
Nylon 6,6: ~4-4.5%
Polyester: ~0.4%
Polypropylene (PP): ~0% (hydrophobic)
Step 3: Comparing: Nylon's moisture regain is lower than cotton's but higher than polyester's. It's also lower than wool's and higher than polypropylene's.