Final answer:
During the chemical phase of perming, a dilute solution of hydrogen peroxide, known as the neutralizer, is applied to reharden and fix hair into its new shape by reforming disulfide bonds.
Step-by-step explanation:
Chemical Phase of Perming and Disulfide Bonds Formation
During the chemical phase of perming, an oxidizing agent, typically a dilute solution of hydrogen peroxide which is also known as the neutralizer, is applied to reharden and fix hair into a new wavy or curly shape. This agent is crucial in the perm process as it reforms the disulfide bonds in the hair's keratin structure. Originally, disulfide bonds are disrupted by a reducing substance, commonly ammonium thioglycolate. After the hair is set on rollers or curlers into the desired shape, the oxidizing agent is applied which causes the broken disulfide bonds to reform, locking the hair into its new shape.
The reformation of disulfide bonds, which are strong covalent bonds between different protein chains or loops within a single protein chain, is what makes the perm or "permanent" hairstyle endure for several months.