Polymeric organic coating for electroluminescent lamp components, particularly for phosphor particles and electrodes and a method of making same, wherein the polymer is formed using an initiator, preferably by ring-opening metathesis polymerization. A dense hydrophobic organic coating is formed which is capable of protecting the electroluminescent device components from exogenous agents such as moisture and eventual degradation. The polymer layer may be attached to an outer surface of the component by one or more tethering layers.