Regolith Simulant Adhesion to Polycarbonate and PDMS: Deposition Methods, Coverage, and Removal Resistance

ABSTRACT

Dust adhesion is a critical challenge for lunar and Martian surface operations, causing equipment degradation, and reduced operational lifetimes. This study investigated the adhesion of three regolith simulants, Lunar Highlands Dust Simulant (LHS1D), Lunar Mare Simulant (LMS1), and Mars Global Simulant (MGS1), to polydimethylsiloxane (PDMS) and polycarbonate using two deposition methods: air deposition and rolling contact. Polycarbonate showed significantly lower area coverage than PDMS across all simulants and deposition methods ( p < 0.001). This was unexpected, as PDMS has lower surface energy, higher hydrophobicity, and higher roughness – properties typically associated with reduced adhesion. However, PDMS has a lower Young's modulus (3.2 MPa vs. 2.9 GPa), which may allow greater surface deformation and increased contact area. Experiments with a stiffer PDMS formulation (4.2 MPa) supported this, showing reduced adhesion with increased modulus. Rolling contact generally produced higher coverage than air deposition, and the finest simulant (LHS1D) showed the highest adhesion, consistent with increased van der Waals interactions for fine particles. Drying significantly increased adhesion on both materials. These findings suggest that substrate stiffness may play a more significant role than surface energy in controlling regolith adhesion, and that rigid, high‐modulus materials warrant further investigation for dust‐exposed surfaces in space environments.