Why should Nylon Plastic Products be boiled in water?

Analysis of the reasons why nylon parts are boiled in water.

1 The Nylon Plastic we commonly use is Nylon 6 (PA6), nylon 66 (PA66), which is a crystalline thermoplastic material.

2 Nylon Plastic Materials are easy to absorb water and contain hydrophilic groups (amido groups).

For crystalline polymers, during injection molding, the rapid cooling makes the material unable to crystallize and shape naturally, resulting in strong internal stress inside the material. Nylon materials that have not undergone "tempering" treatment have their internals after being shaped, macro molecules will still tend to natural orientation and crystalline movement, which will further aggravate the internal stress of the material. Therefore, the nylon parts that have not undergone the boiling process are very brittle, and are easy to collapse or break when subjected to external forces.

So, what if the Molded Nylon Plastic macro molecules are allowed to naturally orient and crystallize to eliminate the internal stress as much as possible?

That is what we are talking about. The boiling process is actually similar to our metal "tempering" process. That is to let the nylon parts soak in a certain water temperature, so that the macro molecules inside tend to the natural orientation as much as possible and achieve the balance of internal crystallization and decrystallization, thereby eliminating its internal stress. The manifestation is that the toughness of nylon parts is greatly enhanced, and the brittleness is basically eliminated.

So why boil it in water?

That is because Nylon Plastic contains a hydrophilic group-amido group, which makes nylon easy to absorb water, but after nylon absorbs a certain amount of water, it helps the orientation and crystal movement of its internal macro molecules.