In the design and construction of cars, it is important to prevent the transmission of noise distributed from engine or body shake. In automotive applications, damping materials are generally placed on sheet metal panels exhibiting high vibration levels. The use of insulators such as foam, bitumen insulators, use of rubber sealant and insulation coatings are among the methods considered. Another method used to reduce noise and acoustic losses is using polymeric materials such as butyl on the floor and body of the car cab. These materials are highly resistant to moisture, heat, chemicals and extreme cold, and adhere well to steel and galvanized surfaces. Usually the sound insulation process starts from the doors, which not only reduces noise but also improves acoustics. In general, temperature, sound frequency and surface geometry influence the rate of noise reduction.
These sheets are used in the automotive industry to control and absorb vibration in the body, front tray, roof and door, and can be installed in paint or decoration step.
This product consists of a viscoelastic polymer that is assembled on a hard aluminum. Polymer with hard metal is used as a unique compound to reduce noise and vibration in the temperature range of 5 to 40 °C. The viscoelastic layer reduces vibration by creating molecular stretches or heat generation. Unlike foreign product, this product is free of bitumen, lead and environmental harmful oils. To fabricate this product, a combination of polymers with different molecular mass was used to damp a variety of input frequencies.
- Good thermal stability, anti-shock
- Easy to apply
- No need for an oven to assemble
- Low relative weight compared to bitumen insulators
- High vibration absorption and up to 3 times higher than bitumen insulators
The sample containing nanoparticles showed higher tensile strength and adhesion than the sample without nanoparticles. Since the product should have a high adhesion for the sound damping, the increased adhesion which caused by increase in the intermolecular forces at the product and substrate interface, improves the product life and reduces the risk of corrosion.
| Strength | Control specimen | Specimen with nanoparticles |
| Tensile Strength (kg/cm2) | 0.3 | 0.64 |
| Adhesion Strength (kg/cm2) | 9 | 16.5 |
