Coating noise-damping

Noise-damping coating. [Data from Wesch, K. Ruch, K., us Patent 5,756,555, May 26,... 

This is sprayable plastisol which can be used for coating substrates which require noise-damping especially of high-frequency components. 

Hutchinson and coworkers examined a wide range of IPNs, SINs and semi-IPNs that were useful as reinforced elastomers. PU/PMMA semi-IPNs prepared by bulk polymerization are used in shaping polymer articles. Epoxy/PU semi-IPNs are used as adhesives. Ion exchange resins are prepared from chloromethyl PS/sulfonate PS IPNs. PS/PS IPNs are used to prepare optically smooth plastic surfaces. Poly(ethyhnethacrylate)/poly(ra-butyl acrylate) prepared by Sperling et find the applications as noise damping coatings. 

Application of special-purpose coatings (anti-condensation, noise damping, etc.). 

Sperling and Thomas employed gradient IPNs to obtain a hard exterior, a soft interior, and a composition-graded intermediate zone. Such materials were useful for noise and vibration damping as explored in Section 8.8. Predecki swelled hydroxyethyl methacrylate monomer mixes into silicone rubber to produce materials having hydratable surfaces. Such materials could replace surface coatings in arteriovenous shunts. 

L. H. Sperling, T.-W. Chiu, R. G. Gramlich, and D. A. Thomas, Latex IPN Coating System for Damping Noise and Vibrations over a Broad Temperature Range, U.S. Nat. Tech. Inform. Serv., Ad Rep. No. 765511/1. Latex IPNs as damping materials. 

Mica is also used in high density polyethylene to make blow molded rear seat backs and load floors used in intermediate size cars and vans to replace much heavier steel assemblies. The mica imparts stiffness and heat resistance. Mica is very effective in foamed plastics, especially polyethylene copolymers, and modified polyfphenylene oxide). It promotes a very uniform cell structure with improved strength and stiffness, and unexpectedly increased impact resistance. The high stiffness of mica gives improved sound transmission, so that it is used in loudspeaker cones, cabinets and earphones. Paradoxically, mica is the preferred mineral in coatings based on polyurethane or asphalt binders to reduce road and motor noise and to damp vibrations. 

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