Polymers can be arranged in two formations. If the molecules do not have a long-range order, the polymer chain has an amorphous arrangement. Amorphous polymers are generally transparent.
Contact lenses, plastic windows and transparent food wraps are generally made of amorphous polymers.
What about polymers those are not transparent? Translucent and opaque polymers have crystalline arrangement of molecules. Here, the atoms and ions are arranged in definite patterns. Generally, the amount of light that can pass through a polymer decreases with increasing amounts of crystallinity. So, the opaqueness of a polymer is an indicator of the degree of crystallinity.
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