The invention relates to a method for producing a multi-material composite and to a multi-material composite.

Due to the stepwise change of material properties at the interface between different materials, in particular metallic and polymeric materials, cracks often develop in multi-material composites, whereby the service life being shortened.

The method according to the invention is based on a gradual adaptation of the material properties of the materials of a multi-material composite at the interface. A composite is formed from at least one metal layer, at least one fibre-reinforced or unreinforced first polymer layer and at least one fibre-reinforced or unreinforced second polymer layer formed from the polymer of the first polymer layer and nanoparticles, said second polymer layer being at least partially disposed between the metal layer and the first polymer layer, under the influence of elevated temperature or elevated temperature and elevated pressure, wherein nanoparticles of the second polymer layer diffuse into the first polymer layer so that a gradient layer is formed in which the nanoparticle concentration decreases in the direction of the first polymer layer.

The multi-material composite produced by the method according to the invention has a particularly long service life and can be used, for example, in drive shafts for the aviation, automotive, or shipping industry.

Process for producing a pressure-sensitive adhesive comprising expanded microballoons, wherein the constituents for forming the adhesive are mixed in a first mixing assembly, the mixed adhesive is transferred into a second mixing assembly into which, at the same time, unexpanded microballoons are fed, the microballoons are expanded in the second mixing assembly or on exit from the second mixing assembly, the adhesive mixture with the expanded microballoons is shaped to a layer in a shaping assembly in which expanded microballoons which have broken through the surface are pressed into the layer surface and the layer of adhesive mixture together with the expanded microballoons are optionally applied to a weblike backing material.

There is provided an inorganic particle composite body comprising a layer of a substrate formed of a plastically deformable solid material and an inorganic particle layer that is composed of inorganic particles that do not plastically deform under a condition under which the solid material plastically deforms, that contains gaps defined by the inorganic particles, and that adjoins the layer of the substrate, wherein part of the solid material is in at least part of the gaps in the inorganic particle layer. This inorganic particle composite body is produced by a method including a preparation step of preparing an inorganic particle structural body comprising a layer of a substrate formed of a plastically deformable solid material and an inorganic particle layer that is composed of inorganic particles that do not plastically deform under a condition under which the solid material plastically deforms, that contains gaps defined by the inorganic particles, and that adjoins the layer of the substrate; and a filling step of plastically deforming at least part of the solid material contained in the inorganic particle structural body, thereby filling at least part of the gaps in the inorganic particle layer with part of the plastically deformed solid material.