Modification of hydrogenated Bisphenol A epoxy adhesives using nanomaterials

Color-stable hydrogenated Bisphenol A (HBA) epoxy adhesives, containing organic–inorganic hybrid nanomaterials, were prepared and their properties investigated. Poly(propylene glycol)bis(2-aminopropyl ether) (D230) was used as the room temperature curing agent, and functional organic–inorganic hybrid nanomaterials, to tailor the adhesives, were prepared by a sol–gel reaction of 3-glycidoxypropyltrimethoxysilane and tetraethoxysilane. The commercial polyhedral oligomeric silsesquioxanes (POSS) having epoxy functional groups were also used. The concentration dependence of different nanomaterials, containing epoxy functional group for HBA/D230 adhesives, was studied. The tensile strength increased with the addition of nanomaterials having glycidyl epoxy group; however, the dependence varied with the size, the number of functional groups, and the amount of the addition. HBA/D230 adhesives containing different amounts of nanomaterials, whose compositions are similar to that of granite, were applied to the Korean granite and the results were compared with those obtained by using commercial adhesives, which have the problem of significant color change and high viscosity. The mechanical properties of HBA/D230 adhesives, containing POSS having glycidyl epoxy group, are found to be similar to those of commercial adhesives. Besides, it has low viscosity and long-term color stability.