Viscoelastic MDI-Based Polyurethane Foam for Sound and Vibration Dampening in Automobiles

The need for noise control became obvious when the U.S. Environmental Protection Agency (EPA) began in the early 1970's to seriously investigate the impact of vehicle noise on the welfare of Americans. One way of reducing interior noise in automobiles is through the use of sound absorbing and vibrational dampening materials. One example of an excellent medium for vibrational dampening is viscoelastic polyurethane foam.

An extensive description of the application of viscoelastic MDI-based foam for automotive carpet backing is presented in this paper. Acoustical and physical comparisons among viscoelastic foam, HR foam, and fiber pad are also presented.