Crystalline polymers

A family of polymers characterized by their molecules' ability to form an ordered arrangement during solidification.

Because the molecules are able to fit closely together in an ordered state, crystalline polymers are typically more dense than amorphous polymers. No polymer can reach 100% crystallinity, some molecules will always remain in a disordered state and form an amorphous part of the material.

Crystalline polymers display an X-ray diffraction pattern, which can be used to detect the degree of crystallinity (from the intensity) and identify the polymer (from the pattern).