Fabrication of Silane and Desulfurization Ash Composite Modified Polyurethane and Its Interfacial Binding Mechanism

Polyurethane/desulfurization ash (PU/DA) composites were synthesized using “one-pot method”, with the incorporation of a silane coupling agent (KH550) as a “molecular bridge” to facilitate the integration of DA as hard segments into the PU molecular chain. The effects of DA content ( φ ) on the mechanical properties, thermal stability, and hydrophobicity of PU, both before and after the addition of KH550, were thoroughly examined. The results of microscopic mechanism analysis confirmed that KH550 chemically modified the surface of DA, facilitating its incorporation into the polyurethane molecular chain, thereby significantly enhancing the compatibility and dispersion of DA within the PU matrix. When the mass fraction of modified DA (MDA) reached 12%, the mechanical properties, thermal stability, and hydrophobicity of the composites were substantially improved, with the tensile strength reaching 14.9 MPa, and the contact angle measuring 100.6°.