| 摘要 |
A process for forming sound absorbing laminates and the resulting laminate which comprises at least one layer of nonwoven fibers bonded to a substrate by a thermoplastic adhesive. The laminate is formed by placing a layer of bonded nonwoven fibers into contact with a substrate and bonding the layer of nonwoven fibers to the substrate. The improvement comprises:
utilizing at least one layer of nonwoven fibers coated with an aqueous emulsion of a vinyl acetate-ethylene (VAE) adhesive and then dried. The VAE adhesive is prepared by aqueous emulsion polymerization, contains crystalline ethylene segments and has:
(a) a crystalline melting point (T m ) ranging from 35 to 110 °C, preferably 50 to 100 °C; measured at a heat rate of 20 °C/minute; and,
(b) a tensile storage modulus of at least 1 x 10 4 dynes/cm 2 at 115 °C measured at a test frequency of 6.28 rad/sec. |
