Is EVA rubber or plastic?

Ethylene-vinyl acetate copolymer (EVA) is an elastomeric (naturally stretchy) polymer that produces materials which are "rubber-like" in softness and flexibility. EVA stands for plastic, made by mixing ethylene and vinyl acetate. Together, they create a material that can be used for shoe soles in EVA sneakers.

What is EVA used for?

One of the most commonly used non-degradable polymers in implantable controlled-released applications is EVA, a copolymer of ethylene and vinyl acetate (VA). EVA is biocompatible and non-toxic; the FDA has approved it for pharmaceutical applications. The VA content in an EVA copolymer can range between 0 and 40%, affecting the properties of the copolymers, including polarity, adhesion, impact resistance, flexibility, optical properties, compatibility, stiffness, softening point, melting point, and crystallinity. Various grades of EVA copolymers have good printing potential and have been used in pharmaceutical applications for decades to develop implantable drug delivery systems, such as custom-made T-shaped IUS and subcutaneous rods by FDM. EVA was used to print 5% and 15% indomethacin-loaded filaments. It was found that the indomethacin in the 3D-printed prototypes was amorphous, while it was crystalline in the corresponding HME filaments. This difference affects the drug release profiles from the filaments and printed prototypes, leading to a faster release from the prototypes prepared by AM.

What are the Advantages of Ethyl Vinyl Acetate?

Some known advantages of ethyl vinyl acetate are:

Crack resistance,

Flexibility and endurance at both low and moderate temperatures,

It can be easily processed by thermoplastic as well as rubber processing techniques,

Resilient,

High transparency with increased vinyl acetate amount,

Excellent heal seal strength,

30% lighter than PVC.