adhäsiv

An adhäsiv, or adhesive, is a substance used to join two surfaces by forming an attachment at the interface. Adhäsiva are designed to create a bond through chemical interactions, mechanical interlocking, or a combination of both. They cure, dry, or set by various mechanisms, such as chemical hardening, solvent evaporation, or cooling, and are selected for compatibility with the substrates and operating conditions. Adhäsiva are used across industries to replace or supplement mechanical fasteners.

Common categories include natural adhesives (starch, casein, gelatin, animal glues) and synthetic adhesives (epoxies, polyurethanes, cyanoacrylates, silicones, polyvinyl acetate, acrylics). Pressure-sensitive adhesives (PSA) provide adhesion under light pressure without curing, as in tapes. Hot-melt adhesives solidify upon cooling and are used for fast assembly. Many adhesives are formulated for specific substrates such as wood, metal, glass, plastics, or textiles.

The performance of an adhäsiv depends on adhesion to the substrate, cohesion within the adhesive, and the ability to withstand environmental exposure. Key properties include tack, shear and tensile strength, elasticity, temperature resistance, and resistance to moisture or solvents. Wetting, surface energy, and clean surface preparation strongly influence bond quality. Safety considerations include volatile organic compounds (VOCs), skin and eye irritation, and flammability.

Applications span construction (lamination, panel bonding), packaging and labeling, automotive and aerospace assembly, electronics, woodworking, footwear, and medical uses such as dental cements and wound closures. Application methods range from manual brushing to automated dispensing and precision jetting, with curing strategies including room-temperature bonding, heat cure, moisture cure, UV or infrared curing.

The development of adhäsiva traces back to natural gums and animal glues and progressed to modern synthetic chemistries in the 20th century. Standards and testing (for example, shear strength, peel strength, and durability) guide formulation and quality control in industries and supply chains.