Which component is commonly used in film-coated polymers to impart flexibility and reduce brittleness?

Plasticizers are commonly used in film-coated polymers to enhance flexibility and reduce brittleness. These substances work by inserting themselves between the polymer chains, effectively increasing the distance between them and reducing intermolecular forces. As a result, the polymer becomes more pliable and less prone to cracking or breaking under stress. This is particularly important in pharmaceutical applications where film coatings need to be robust yet flexible enough to withstand handling and manufacturing processes.

In contrast, stabilizers are primarily used to protect polymers from degradation caused by heat, light, or oxygen but do not significantly contribute to the flexibility of the film. Fillers can be used to increase volume or lower the cost of the formulation but may not necessarily impart flexibility. Colorants are primarily added for aesthetic purposes to provide visual appeal and do not impact the mechanical properties of the film's flexibility. Thus, plasticizers are the key component that specifically addresses the requirement for increased flexibility in film-coated polymers.