Lyophobic

Lyophobic (‘solvent‑repelling’) describes a surface or colloidal system that has low affinity for the surrounding liquid. In aqueous service, lyophobic behaviour corresponds to hydrophobicity: high contact angles, poor wet‑out and a tendency for non‑polar species to adsorb preferentially. In filtration this affects start‑up and test methods (bubble point and porometry require complete wetting), fouling (oils may adhere strongly to lyophobic polymers) and cleaning (solvent choice and temperature must overcome low surface affinity). Engineers tune lyophobic/lyophilic balance via polymer selection, plasma or chemical surface treatments and coatings, targeting fast wet‑out where aqueous clarity matters or elevated lyophobicity where water hold‑up must be avoided. Specifications should document initial and retained contact angles after defined CIP cycles and thermal exposure so wettability—and therefore retention and flux—remain predictable over the medium’s life.