EVAc, EVA, EVM: A lot of chefs - but only one signature dish
EVAc, EVA, E/VA, E/VAC, EVM - ethylene vinyl acetate copolymers have a lot of names. To simplify: all these abbreviations actually refer to the same thing.
Nevertheless, over the years, fine differences in terminology have become established. For example, the abbreviations EVAc and E/VA, the latter of which was only used for a short period of time, should in principle no longer be used, but are still employed by some people. According to ISO 1043-1:1987, thermoplastic versions of the material should be referred to as E/VAC. The designation EVM was introduced by staff at what today is LANXESS based on the common rubber nomenclature according to ISO 1629: 1995 (E) in order to indicate the saturated backbone of the ethylene vinyl acetate copolymers in the name - Ethylene Vinyl acetate rubbers with a Methylene main chain.
The most commonly used designation is certainly EVA. However, it has become common practice to use this abbreviation for the traditional ethylene vinyl acetate copolymers with a low vinyl acetate content whose material characteristics are far inferior to the Levapren® grades produced using the medium pressure method. The abbreviation EVM is often used to refer to EVA grades with a high vinyl acetate content to differentiate these from the "simple" EVA grades.