The chemical bonding of extruded polystyrene foam with mortar through UV curable organic-inorganic hybrid coatings

UV curable organic-inorganic hybrid (OIH) coatings were used to modify the extruded polystyrene foam (XPSF) surfaces to increase the bonding strengthen (BS) of XPSF/mortar composite (XMC). OIH coatings contained polyurethane acrylate, hexanediol and nanoparticles with different dimensions. With the addition of nano-SiO 2 and halloysite nanotubes , the BS-D (BS in dry state) & BS-W-2H/7D (BS in wet state after 2-hour/7-day drying) values for modified XMC were increased from 0.050 & 0.039/0.047 MPa to 0.245 & 0.196/0.356 and 0.312 & 0.233/0.323 MPa. The chemical bonding between SiO 2 /-COOH from UV coating and hydration products in mortar improved the bonding state.