Chemical-soaked hair and insufficiently washed hair are more susceptible to thermal denaturation.
Elasticity is 20-30% on dry hair, 50-60% on wet hair, and 70% when wet with perm, meaning hair stretches better when wet.
| Action/Temperature | Dry heat | Damp heat |
| Weakened physical strength | 80 to 100 ºC | Around 60 |
| Thickening of the hair | Around 120 | |
| Cystine Reduction | 150 | Around 100 |
| If α-keratin is Change to β-keratin | Around 180 | Around 130 |
What is Hair Elasticity? – The keratin in your hair has a coiled, spring-like structure that allows the hair to stretch and return to its original position when you pull and release it, a property known as hair elasticity.
The furry polypeptide is helical in its normal state, but when pulled, it becomes oblique and stretches up to twice its length. However, if it is stretched too much, it loses its ability to return to its original shape and sags. The force at which it breaks is called the tensile strength. Wet hair has more elasticity but less tensile strength. .
