 Solid masterbatches are also solvent-free, therefore they tend to have longer shelf life as the solvent won't evaporate over time.The masterbatch usually contains 40-65% of the additive, but the range can be as wide as 15-80% in extreme cases.The carrier material of the masterbatch can be based on a wax (universal carrier) or on a specific polymer, identical or compatible with the natural polymer used (polymer-specific).