What is a common consequence of applying a sodium hydroxide relaxer on hair previously treated with ammonium thioglycolate?

When sodium hydroxide relaxers are applied to hair that has previously been treated with ammonium thioglycolate, a common consequence is breakage. This occurs because both sodium hydroxide and ammonium thioglycolate are strong chemical agents that alter the hair's structural integrity in different ways. Sodium hydroxide is a highly alkaline substance that works by breaking down the disulfide bonds in hair, while ammonium thioglycolate alters these bonds through a different chemical reaction.

Using these two different relaxers in succession can create an incompatibility, as the hair may already be weakened from the first treatment. The cumulative chemical stress can lead to significant damage to the hair fibers, making them more prone to breakage. This is especially true if proper precautions and bonding treatments are not implemented between processes, leading to a compromised hair structure. Understanding the chemistry behind these relaxers helps inform best practices in hair treatment to prevent damage.