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Sound-Absorbing and Flame-Retarding Property of Nonwoven Compounded PU foam Planks

A nonwoven is an ideal sound-absorbing material due to its high surface area. Surface area of a nonwoven correlates with fiber denier and packing density, and affects the sound absorbing property. With smaller denier, sound waves have great chance to interact with fibers. Moreover, more fibers would produce friction in-between sound waves at high packing density. Besides, a large amount of fabrics are produced in the current textile industry. During the production process, selvages are cut form fabrics and then abandoned, thus leading to amazing wastes after a long period of discarding. This study used recycled selvage fiber to prepare composite nonwovens, and then compounded with polyurethane foam, forming sound-absorbing/flame-retarding composite planks. Porous and vibration absorbing mechanism was combined for improving sound the absorbing property. And effects of fiber denier, needle-punched density for nonwoven and foam density of PU foam on properties including sound-absorbing and flame-retarding are discussed. Results show that the sound absorption coefficient of the resultant composite plank was above 0.8 at medium frequency. Superficial composite nonwoven achieved the effect of delayed burning time.