Insect Abatement On Lubricious, Low Adhesion Polymer Coatings Measured With An Insect Impact Testing System

Insect debris disrupts laminar flow, obstructs operator vision, and degrades vehicle aesthetics. To protect vehicle surfaces, anti-contamination coatings have been under development for 70 years, but no known homogeneous coating both adequately reduces debris and survives on vehicle surfaces. Coatings with synergistic combinations of physical properties and materials, however, may enable improved anti-fouling and maintain long-term durability. Transparent, spray-on coatings were developed that contain a combination of fluorinated and hygroscopic chemistries in which the fluorinated component reduces wetting of insect debris while the hygroscopic component produces a lubricating layer of absorbed water that interferes with debris adhesion. Debris area after insect impact was approximately twice as low on these coatings as compared to homogeneous control materials. Furthermore, the sensitivity of debris accumulation to hygroscopic content, and thus lubricity, was measured. At least 13 wt% hygroscopic content in the developed coatings was required for decreased debris accumulation compared to a pure fluorinated surface. Lastly, resistance to common vehicle fluids and scribe-tape adhesion was measured on fluorinated-hygroscopic coatings as initial demonstrations of durability.