why are metals so apt to corrode while polymers are immune to corrosion?
Metals are prone to corrode because they have metallic bonding, where atoms share electrons in a sea of delocalized electrons. This type of bonding allows for easy movement of electrons within the metal structure, which makes metals good conductors of electricity but also makes them susceptible to corrosion.
Corrosion occurs when metals are exposed to oxygen, moisture, or other corrosive agents. The metal atoms lose electrons, resulting in the formation of metal ions. The movement of electrons from one area of the metal to another creates an electrochemical reaction, leading to the breakdown of the metal structure over time.
On the other hand, polymers, which are made of long chains of repeating molecular units, have covalent bonding. This type of bonding involves the sharing of electrons between atoms, creating strong bonds within the polymer structure. These covalent bonds make polymers more resistant to the movement of electrons, and thus less prone to corrosion.
While polymers are generally more resistant to corrosion than metals, it's important to note that certain polymers can still be affected by certain corrosive agents, such as strong acids or bases. However, compared to metals, the corrosion resistance of polymers is generally much higher.