PolyOxyter, an additive masterbatch product, has been specially formulated with reactive compounds to provide performance enhancement and processing improvement for Polyesters, Nylons, and Polycarbonates. The product has been formulated to provide performance enhancement in both extrusion and molding processes. When used at a typical 3% to 7% let-down, PolyOxyter has been shown to produce many impressive benefits, such as: a widened processing window, improved compatibility between dissimilar resins, controlled crystallinity and often crystallinity reduction, elimination of weld lines & warpage, frost line elimination and scrap reduction, stabilized melt viscosity, improved printability, improved dispersion of additives, increased loading capacity for fillers and additives, improved adhesion properties with polar surfaces, reduced hydrolytic breakdown, and enhanced clarity. PolyOxyter can also improve the properties of packaging materials. As an additive, the product can be co-extruded into multi-layered film with improved vapor barrier properties for enhanced resistance to moisture, oxygen, and carbon dioxide penetration, and improved interlayer film adhesion. When used with PET applications, PolyOxter controls crystallinity in the stretching process, reduces hydrolytic breakdown, improves surface adhesion, and optical compatibility. PolyOxyter is coextrudable with PET in cast and blown film operations, and can be applied by solution coating on PET for flexibility. PolyOxyter has a uniform pelletized shape, resembling a clear bead. The product has excellent compatibility with most any amorphous polymer system, such as polyester, polyamide, polycarbonate, polysulfone, polyethersulfone, polyketone, etc. PolyOxyter is manufactured using FDA compliant ingredients.