Method for selecting an interlayer for vibroacoustic damping, interlayer for vibroacoustic damping and glazing unit comprising such an interlayer

摘要

A method for selecting a viscoelastic plastic interlayer including two outer layers and a central layer. The interlayer is for incorporation between two glass sheets of a glazing unit. The method of selection includes providing first and second components respectively as the central layer and the outer layers, and measuring the shear modulus G′ of the first and second components. The material of the second component is selected only if G′ is a certain value at a specific temperature and frequency range. The thickness h of the first component is set so that h is a specific value and so that g=G′/h is within a specific range of values at a specific temperature and frequency range. The method optimizes the damping of the second and third natural frequencies of a vehicle windshield without weighing down the windshield.

主权项

1. A viscoelastic plastic interlayer intended to be incorporated between two glass sheets of a glazing unit, the interlayer providing vibroacoustic damping properties to the glazing unit, the interlayer comprising:
two outer layers made of a viscoelastic plastic material, a shear modulus G′ of the outer layers being greater than or equal to 3×107 Pa at 20° C. and for a frequency range between 100 Hz and 240 Hz; a central layer having a thickness h and having vibroacoustic damping properties such that h is less than or equal to 0.3 mm and such that a shear parameter g of the central layer is between 8×108 Pa/m and 2.67×109 Pa/m at 20° C. and for a frequency range between 100 Hz and 240 Hz, where g=G′/h, wherein the central layer is disposed between the two outer layers.