Ethylen / Vinylacetat (EVA)
The Ethylen / Vinylacetat (EVA) is used to describe a group of co-polymers. Examples include cold-resistant extractable spouts of canisters, plastic sheets used in agriculture and horticulture, shrink-wraps (office supplies, solar modules), shower curtains, and flooring. A subclass of EVAs extending up to 28% VA is mainly used as melt adhesive.
In photovoltaics, solar cells are embedded in EVA. In this process, the EVA contained in plastic sheets is melted at a temperature of about 150 °C (300 °F), becomes crystal clear and cross-links three-dimensionally. When cooled off, the resulting bond is highly durable and serves to protect the cells against environmental stress.
If VA content is higher than 30% (it may reach up to 90%), the resulting elastomer is similar to natural rubber. It is often called EVM (DIN I ISO 1629:1995), and is primarily used for shoe soles or as a polyblend together with other elastomers.