The Nomenclature of Levapren
Levapren® is formed by copolymerization of ethylene and vinyl acetate. In principle Levapren consists of methylene units forming a saturated polymer backbone with pendant acetate groups. These rubber-like polymers are designated "EVM"(1) according to ISO 1629: 1995 (E) nomenclature. The presence of a fully saturated main chain is an indication that Levapren® is a particularly stable polymer. Degradation generally only occurs at very high temperatures and even then very slowly.
(1)In accordance with ISO 1043-1: 1987, the abbreviation E/VAC is to be used thermoplastics. The abbreviation EVA is also frequently used.
At a glance
- The "M" in the designation refers to the saturated backbone of the methylene main chain of the EVM
- While the abbreviation EVA usually describes "conventional" ethylene vinyl acetat copolymers, the designation EVM has become established for grades with vinyl acetat content
The polymers are used as synthetic rubbers, as adhesive raw materials or as modifiers in thermoplastics, specifically PVC. The adhesive raw materials are sold under the brand name Levamelt®, while powdered grades are distributed under the brand of Baymod®L. The main differences between the grades are in the vinyl acetate content and the polymer viscosity.