EVA insulation

The typical weight percentage of vinyl acetate in EVA insulations ranges from 10 to 40 percent. The rest of the weight is composed of ethylene. In certain types, it is possible that other chemical additives might appear in very small percentages.

EVA is an elastomeric polymer that, due to its softness and flexibility, creates materials that are rubber-like. The very good properties of the material, especially in terms of low-temperature toughness, resistance to cracks or water, clarity, and gloss, make EVA a widely used product suitable for the production of many items.

Generally, it can be said that there are three different types of EVA copolymers, which differ in the content of vinyl acetate and the method of using these materials.

The first is the EVA copolymer, which is based on a low VA content (approximately only about 4%), often referred to as polyethylene modified with vinyl acetate. It is a copolymer and is processed as a thermoplastic material, similar to low-density polyethylene. It has similar properties to this material but differs, for example, in increased gloss, softness, and flexibility. This material is considered non-toxic.

The second type is the EVA copolymer, which is based on a medium VA content (ranging between 4 and 30%). It is referred to as a thermoplastic ethylene-vinyl acetate copolymer. It is an elastomeric material. Although not vulcanized, it has some properties of rubber or plasticized polyvinyl chloride. Both filled and unfilled EVA materials have relatively good properties at low temperature, maintaining high rigidity. Materials with approximately 11 percent VA content are used as hot-melt adhesives.

The last type is the EVA copolymer, which is based on a very high VA content (usually from about 40% and above). It is referred to as ethylene-vinyl acetate rubber.