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Sound-Absorbing Composites Based on Flax and Polymer Fibers

The paper considers sound absorption of the composite materials, which are based on the natural flax and polymer fibers. The thickness of a single layer of obtained nonwoven composite is about 10 mm. The analysis of absorption dependences is carried out for different thicknesses of the material. It is shown that in the low frequency range the absorption almost linearly increases depending on the thickness. The coefficient of the normal absorption increases with the frequency in the range from 50 Hz up to 1600 Hz. The hot-pressed material can be used for panel production. The sound absorption increases with the thickness of the pressed material. The measurements show the possibilities of application of the composite for the production of the parts of cabs’ interior.