Sound dampening

Note high vinyl SIS (SVS) used for sound dampening ... 

Further, these materials exhibit a high energy absorption and high sound-dampening properties. These properties are retained under cryogenic conditions. However, in general, adhesion of UHMWPE to substrates is poor, even when the suiface is roughened. 

The strength-to-weight ratio of structural foams is reported to be 2 to 5 times greater than that of metal. Another important property is sound dampening (5). 

Magnetite (Fe304), a common iron ore, adds density and magnetic properties to a resin for sound-dampening or anti-static/low-resistivity applications. The filler also absorbs microwave energy and resists visible scratches. Added at 60%-80% in 9-pm or higher particle sizes, magnetite reportedly can be processed with common equipment [7-18]. 

Perhaps the ultimate low-weight use of foamed POs in vehicles comes in the form of expanded polypropylene (EPP) bead materials, which can be molded into cushioning materials for sound-dampening, seating, storage systems, energy absorption, and occupant protection. A couple of recent uses of EPP are covered in Case 13.2. 

Chem. Deserp. Wet ground muscovite mica CAS 12001-26-2 EINECS/ELINCS 310-127-6 Uses Reinforcing agent, filler for plastics, sound dampening, foundry coating, etc. 

Thermosets also benefit from the foam structure, as evidenced by improved thermal insulation, sound dampening and mechanical stress absorption responses to temperature changes or impact. Hollow spheres with an already set volume are normally used, that is, pre-expanded microspheres. The reason is that the curing reactions often interfere with any expansion before a sufficient volume increase has been obtained. Hollow organic spheres are found in products such as sealants, adhesives, putties, pipes, cultured marble, body fillers, model-making materials, and pastes [2, 3, 19]. Common suitable matrix materials are epoxies, PUR, and polyesters. 

Sound dampening and insulation Wall coverings for music studios, coatings for car ventilation units, computer and printer housings. 

The new effects category of benefits includes a wide range of characteristics such as sound dampening, thermal and electrical insulation, energy absorption, and the host of possibilities for marrying different characteristics, for... 

MAJOR PRODUCT APPLICATIONS paints, inks, wood finishes, powder coatings, adhesive, mastics, seals, sealants, coatings, medical, paper, battery products, drilling fluids, brake linings, bowling balls, sound dampening, plastisols, urethane foams, acoustical compounds, insulating materials... 

A common type of adhesive for electronics is the hot melt PUR adhesives (HMPURs) which have the necessary high temperature resistance, the fast production speeds and the viscoelastic properties of an elastomer and are found in audio speakers, electronic enclosures, and the installation of sound dampener systems [50]. 

Over time, I began to realize that people select materials based on feel all the time. Furniture makers select wood based on its grain and sheen, and how it feels when you touch it. Products of all kinds, both consumer and industrial, have gaskets and vibration absorbers and sound dampeners. And when it comes to cams and mechanisms— the really geeky stuff— engineers often select materials based on the sound they make or the vibration they make—or do not make. All of these material choices are based on feel. 

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