<p>The production of a latex dispersion by emulsion polymerization results in particle and reaction fouling of heat exchange surfaces. Fouling during emulsion polymerization deteriorates heat transfer efficiency, prevents continuous reactor configurations, and increases the frequency of cleaning operations. The investigation of fouling during emulsion polymerization is challenging due to the changes in the material properties of the bulk fluid during the course of the reaction. This contribution presents the design of a reactor setup that employs an integrated movable heated finger for the study of fouling during emulsion polymerization. A heated finger with ‘movable’ functionality has yet to be applied in previous fouling studies. This functionality has the potential to greatly reduce the experimental effort in the production of reaction fouling deposits for ex-situ analyses. To identify key design parameters for a movable heated finger, preliminary design screening was first conducted with prototype heated fingers. The design screening emphasized considerations such as the type of heat supply (electric vs. fluidic) and the uniformity of the heat flow. Experiments involving the retraction of the prototype heated fingers from a polymer dispersion during fouling demonstrated the need to decouple the changes in the overall heat transfer coefficient due to fouling versus the changes due to retraction of the finger into air. The preliminary design screening motivated a redesigned heated finger which was commissioned using various tests to characterize the heat flow in water and quantify the fouling of a preformed latex. The commissioning tests for the redesigned heated finger demonstrated the following: (1) a significant impact of the surface area of the finger in air on the heat required to maintain a constant surface temperature in liquid, (2) a higher fouling rate with a constant heat flux operation than a constant surface temperature operation, and (3) a dependence of the value of the convective heat transfer coefficient on the retraction height of the finger. Discrepancies between the experimental and theoretical convective heat transfer coefficients emphasize the need to reevaluate the significance of axial heat flow in further development of the movable heated finger design. Ultimately, the successful implementation of a movable heated finger provides a method to create a time lapse of the fouling process along the length of the finger within a single experiment.</p>