Undesirable residue formation and lower performance can be observed during the use of polymer-based chemical additives in the petroleum industry when such compounds are mixed during a number of operations, such as oil production. In this work a demulsifier, a flocculant and a scale inhibitor and their respective polymeric bases were tested. These were evaluated through specific performance tests for each additive and a solubility test to assess residue formation. By correlating the performance of commercial additives and the respective polymeric bases, we can conclude that the polymeric base is responsible for the positive synergistic effects on demulsifier performance in the presence of other additives and for the negative synergistic effects on scale-inhibiting performance, also in the presence of other additives. Moreover, we found that the polymeric base can be responsible for the residue formation from the scale inhibitor and flocculant mixture, although it is not be responsible for the residue formation of the flocculant alone.