Reactive hot melt structural adhesives comprising urethane oligomer and epoxy mixture in specified ratios. The compositions offer very high shear, peel, and impact strengths, properties of particular value in bonding adherends in an auto body assembly line.

An improved urethane reactive hot-melt adhesive is provided that improves the green strength of bonded joints is provided. Also provided are an improved method of bonding articles together with such an adhesive and improved composite articles bonded together with such an adhesive.

An improved urethane reactive hot-melt adhesive is provided that improves the green strength of bonded joints is provided. Also provided are an improved method of bonding articles together with such an adhesive and improved composite articles bonded together with such an adhesive.

A free-flowing, powdery masterbatch including a metal oxide, having a material that is absorbed within the intra-aggregate void space of the metal oxide and a resin system incorporating same are disclosed. The material that is absorbed within the intra-aggregate void space of the metal oxide is selected from, but not limited to, organic materials and polyorganosiloxanes (commonly referred to as silicones). The organic materials, whether monomeric, polymeric, or elastomeric, more preferably include, but are not limited to, acrylics, alkyds, epoxies, formaldehydes, glycols, polyamides, polyesters, polyethers, polyimides, polyolefins, polyols, polysulfides, polyvinyl acetate, polyurethanes, silicones, or mixtures thereof. The polyorganosiloxanes may include various functional groups, for example methyl, phenyl, vinyl, trifluoro, chloro and combinations thereof. The metal oxide is selected from the group consisting of silica, alumina, ceria, titania, zirconia and mixtures thereof. Also disclosed is a method for producing the free-flowing, powdery masterbatch and the resin system incorporating the masterbatch.