Polyvinyl chloride (PVC) is one of the major synthetic resins, andis widely used in the building, packing, and automobile industry.Additives such as calcium carbonate (CaCO3) and di-n-octyl phtha-late (DnOP) are often added in production of plastics to improve theproperties of plastics or lower the cost [14–16]. Based on our previ-ous study, additives have certain impacts on the flotation behaviorof waste plastics [17]. From preliminary tests, it was found thatthere were significant differences in the flotability of PVC plasticsin various application areas. The natural flotability is defined asthe flotation recovery when flotation tests are conducted withoutreagents. This paper focuses on the effects of additives on the sur-face of PVC plastics and further investigates the natural flotabilityof PVC plastics.