Abstract: Provided herein are acoustic articles (100) that include a porous layer (102) and heterogeneous filler (104) received in the porous layer. The heterogeneous filler is substantially non-porous and present in an amount of from 0.25% to 7% by volume relative to the total volume of the porous layer and has a specific surface area of from 0.01 m2/g to 1 m2/g. The acoustic article has a flow resistance of from 500 MKS Rayls to 12,000 MKS Rayls.

Abstract: Described herein are noise-resistant assemblies pursuant to various commercial and industrial applications. The noise-resistant assemblies can include duct assemblies, pool assemblies, motor assemblies, carpet flooring assemblies, and roofing assemblies. These assemblies incorporate an acoustic article containing a porous layer and a heterogeneous filler having a median particle size of from 1 micrometer to 1000 micrometers and a specific surface area of from 0.1 m2/g to 10,000 m2/g received in the porous layer.

Abstract: Provided are conduits for air flow that are capable of reducing noise and related methods. The provided conduits include a first section that is tubular and substantially non-perforated and a second section with at least a portion having a multiplicity of microperforations that provide an average flow resistance of from 50 MKS Rayls to 8000 MKS Rayls therethrough. The second section is either (a) tubular and connected in series with the first section, with an outer surface of the second section being in fluid communication with an outer surface of the conduit, or (b) disposed within the first section.

Abstract: Provided are acoustic articles, and related methods, that include a porous layer and heterogeneous filler received in the porous layer. The heterogeneous filler can include clay, diatomaceous earth, graphite, glass bubbles, polymeric filler, non-layered silicate, plant-based filler, or a combination thereof, and can have a median particle size of from 1 micrometer to 1000 micrometers and a specific surface area of from 0.1 m2/g to 800 m2/g. The acoustic article can have an overall flow resistance of from 100 MKS Rayls to 8000 MKS Rayls. The acoustic articles can serve as acoustic absorbers, vibration dampers, and/or acoustic and thermal insulators.

Abstract: A multilayer damping material for damping a vibrating surface comprising: at least one constraining layer; at least one dissipating layer; and at least one kinetic spacer layer comprising multiple spacer elements. The kinetic spacer layer is arranged between the constraining layer and the vibrating surface, when used for damping the vibrating surface. Each spacer element has opposite ends. At least one end of each of the multiple spacer elements is embedded in, bonded to, in contact with, or in close proximity to the dissipating layer, such that energy is dissipated within the multilayer damping material, through movement of the at least one end of each of the multiple spacer elements.

Abstract: Provided are acoustic articles having a porous layer (102,104,106) placed in contact with a heterogeneous filler comprising porous carbon and having an average surface area of from 0.1 m2/g to 10,000 m2/g. The acoustic articles can have a flow resistance of from 10 MKS Rayls to 5000 MKS Rayls. Optionally, the porous layer includes a non-woven fibrous layer or a perforated film having a plurality of apertures with an average narrowest diameter of from 30 micrometers to 5000 micrometers. The heterogeneous filler can enhance low frequency performance without significantly compromising high frequency performance, thickness or weight.

Abstract: Multilayer damping material for damping a vibrating surface (10) including: at least one constraining layer (4); at least one dissipating layer (1, 3); at least one kinetic spacer layer (2) including multiple spacer elements (2b), the kinetic spacer layer being arranged between the constraining layer and the vibrating surface, when used for damping the vibrating surface, wherein each spacer element has opposite ends, at least one end of each of the multiple spacer elements is embedded in, bonded to, in contact with or in close proximity to the dissipating layer, such that energy is dissipated within the multilayer damping material, through movement of the at least one end of each of the multiple spacer elements; absorbing material as at least one additional layer (12) or within at least one of the above layers.

Abstract: Provided are conduits for air flow that are capable of reducing noise and related methods. The provided conduits include a first section that is tubular and substantially non-perforated and a second section with at least a portion having a multiplicity of microperforations that provide an average flow resistance of from 50 MKS Rayls to 8000 MKS Rayls therethrough. The second section is either (a) tubular and connected in series with the first section, with an outer surface of the second section being in fluid communication with an outer surface of the conduit, or (b) disposed within the first section.

Abstract: Dimensionally-stable fibrous structures including ceramic-coated melt-blown nonwoven fibers made of a flame-retarding polymer and processes for producing such fire-resistant nonwoven fibrous structures. The melt-blown fibers include poly(phenylene sulfide) in an amount sufficient for the nonwoven fibrous structures to pass one or more fire-resistance test, e.g. UL 94 V0, FAR 25.853 (a), FAR 25.856 (a), and CA Title 19, without any halogenated flame-retardant additive, and have a ceramic coating. The melt-blown fibers are subjected to a controlled in-flight heat treatment at a temperature below a melting temperature of the poly(phenylene sulfide) immediately upon exiting from at least one orifice of a melt-blowing die, in order to impart dimensional stability to the fibers.

Abstract: The provided articles, assemblies, and methods use a non-woven fibrous web (50) having one or more layers (60) that are densified in situ to provide a layer that is densified relative to one or more adjacent layers, collectively within a unitary non-woven construction. The non-woven web (50) can be made from fibers having a composition and/or structure that resist shrinkage induced by polymer crystallization when subjected to high temperatures. Advantageously, the provided non-woven webs (50) can be molded to form a three-dimensional shaped article that displays dimensional stability.

Abstract: The present disclosure provides an acoustic composite. The acoustic composite includes a first porous layer having a flow resistance in a range of from about 100 Rayl to about 150,000 Rayl. The acoustic composite further includes a second porous layer having a flow resistance in a range of from about 100 Rayl to about 150,000 Rayl. The acoustic composite further includes a perforated membrane adjacent to at least one of the first porous layer and the second porous layer. The perforated membrane includes a first surface and a second surface opposed to the first surface. The perforated membrane further includes a patterned arrangement of a plurality of through-holes each independently extending from a first open end, the first surface including the first open end, to a second open end, the second surface including the second open end.

Abstract: Dimensionally stable fire-resistant fibrous structures including fire-resistant melt-blown nonwoven fibers, and processes and apparatus for producing such dimensionally stable, fire-resistant nonwoven fibrous structures. The melt-blown fibers include poly(phenylene sulfide) in an amount sufficient for the nonwoven fibrous structures to pass one or more fire-resistance test selected from UL 94 V0, FAR 25.853 (a), and FAR 25.856 (a), without any halogenated flame-retardant additive in the nonwoven fibrous structure. The melt-blown fibers are subjected to a controlled in-flight heat treatment at a temperature below a melting temperature of the poly(phenylene sulfide) immediately upon exiting from at least one orifice of a melt-blowing die, in order to impart dimensional stability to the fibers.

Abstract: Provided acoustic devices include an external housing defining an expansion chamber and a wall extending through and partitioning the expansion chamber into a central chamber and a peripheral chamber adjacent the central chamber, wherein an inlet and outlet communicate with the central chamber, and wherein the wall includes a plurality of apertures formed therethrough to allow air movement to and from the central and expansion chambers, the plurality of apertures sized to provide an average flow resistance ranging from 100 MKS Rayls to 5000 MKS Rayls. The acoustic devices advantageously show significant sound attenuation while streamlining air flow to reduce pressure drop across the expansion chamber.

Abstract: A multilayer damping material for damping a vibrating surface comprising: at least one constraining layer; at least one dissipating layer; and at least one kinetic spacer layer comprising multiple spacer elements. The kinetic spacer layer is arranged between the constraining layer and the vibrating surface, when used for damping the vibrating surface. Each spacer element has opposite ends. At least one end of each of the multiple spacer elements is embedded in, bonded to, in contact with, or in close proximity to the dissipating layer, such that energy is dissipated within the multilayer damping material, through movement of the at least one end of each of the multiple spacer elements.

Abstract: Provided acoustic devices include an external housing defining an expansion chamber and a wall extending through and partitioning the expansion chamber into a central chamber and a peripheral chamber adjacent the central chamber, wherein an inlet and outlet communicate with the central chamber, and wherein the wall includes a plurality of apertures formed therethrough to allow air movement to and from the central and expansion chambers, the plurality of apertures sized to provide an average flow resistance ranging from 100 MKS Rayls to 5000 MKS Rayls. The acoustic devices advantageously show significant sound attenuation while streamlining air flow to reduce pressure drop across the expansion chamber.

Abstract: An acoustic composite comprises a flow resistive substrate having a solid acoustic barrier material bonded to at least a portion of a major surface of the flow resistive substrate; wherein the acoustic barrier material has a density greater than about 1 g/cm3 and the acoustic composite has a porosity between about 0.002% and about 50%.

Abstract: Structured films having acoustical absorbance properties are disclosed. Methods of making and using the structured films are also disclosed.

Abstract: An acoustic composite comprises a flow resistive substrate having a solid acoustic barrier material bonded to at least a portion of a major surface of the flow resistive substrate; wherein the acoustic barrier material has a density greater than about 1 g/cm3 and the acoustic composite has a porosity between about 0.002% and about 50%.

Abstract: Structured films having acoustical absorbance properties are disclosed. Methods of making and using the structured films are also disclosed.

Abstract: Structured films having acoustical absorbance properties are disclosed. Methods of making and using the structured films are also disclosed.