Plastics Material Blender and Loader Systems Plastrac, Inc. offers a variety of gravimetric and volumetric material blenders and loader systems that are ideal for a multitude of plastic processing methods. Our plastic processing machines and auxiliary equipment is engineered to make plastics processing easier and more cost-efficient. Plastrac material blenders and loading systems synchronize in real-time with plastics molding machines to provide an accurate and consistent material mixture with no mechanical mixing.