improved solventless processing technology for additive blends containing a polymer carrier , including those which have high level of additives , is described . high concentrations of low - melting , sticky additives lead to phase separation and extrusion instability , such that pellets cannot be formed from such additive blends by traditional extrusion process . these blends include those with a high level of active additives that have been described in the literature as type a superblends . here a polymer typically acts as the carrier of the additives . the new and improved technology involves the solid state compaction processing , using a tubular die , of such impossible - to - pelletize additive blends of the type a composition to produce commercially useful pelletized additive blends .