Abstract: A constrained layer, composite structure for damping acoustic vibrations includes an extensional layer comprised of a first polymeric material, and a constraining layer of a second polymeric material. The modulus of elasticity of the constraining layer is greater than that of the extensional layer. In use, the structure is disposed on the surface of an article in which acoustic vibrations are to be damped so that the extension layer overlies the surface. Also disclosed are methods for preparing the structure, including automated methods.

Abstract: A two layer sound deadening material is formed from pumpable material applied through a pair of extrusion heads mounted on a single mount. A robot, used in high speed mass production automotive assembly lines, moves the door panel relative to the stationary extrusion heads to allow the simultaneous application of the two layers onto the interior side of the door. The first layer is formed of a thermosetting composition containing epoxy, rubber and a catalyst and adheres directly to the door panel. The second layer is formed of a thermosetting composition containing an epoxy resin, a thermo plastic copolymer and a curative which will adhere directly to the first layer due to similar chemical structures. The second layer is positioned such that the edges thereof are inside of the corresponding edges of the first layer to prevent read through transmission of noise from the body or door panel.

Abstract: A two layer sound deadening material is formed from pumpable material applied through a pair of extrusion heads mounted on a single mount. A robot, used in high speed mass production automotive assembly lines, moves the door panel relative to the stationary extrusion heads to allow the simultaneous application of the two layers onto the interior side of the door. The first layer is formed of a thermosetting composition containing epoxy, rubber and a catalyst and adheres directly to the door panel. The second layer is formed of a thermosetting composition containing an epoxy resin, a thermo plastic copolymer and a curative which will adhere directly to the first layer due to similar chemical structures. The second layer is positioned such that the edges thereof are inside of the corresponding edges of the first layer to prevent read through transmission of noise from the body or door panel.

Abstract: A constrained layer, composite structure for damping acoustic vibrations includes an extensional layer comprised of a first polymeric material, and a constraining layer of a second polymeric material. The modulus of elasticity of the constraining layer is greater than that of the extensional layer. In use, the structure is disposed on the surface of an article in which acoustic vibrations are to be damped so that the extension layer overlies the surface. Also disclosed are methods for preparing the structure, including automated methods.