Studying On The Sound-absorbing Materials With Wood Fiber And Polyester Fiber

The paper studied the process and structure as well as properties of composite materialsusing wood fiber and polyester fiber as raw materials，ADC as foamed agent，isocyanate asadhesive by the technology of polymer foam technology and wood-based compositetechnology.The main contents and research results of this paper is shown in the following severalaspects：Polymer foam technology and wood-based composite technology are used to producesound-absorbing composite materials with wood fiber and polyester fiber in this paper, whichstudies effects of the conditions for making process of the sound-absorbing materials on themechanical properties and sound-absorbing performance. The results show that it is feasible toadd the adhesive and a foaming agent into wood fibers and polyester fibers to make a compositematerial. The optimum conditions are that hot-pressing temperature is150°C and compositetime is10min. In a certain temperature range, the mechanical properties are improved alongwith time increasing, while the time has little effect on the acoustic performance. And in acertain time range, as the temperature increases, both the mechanical properties and acousticperformance is improved. The average absorption coefficient of the material is0.65as thetemperature is140℃in the range from1600Hz to4000Hz, while it is0.7in the condition of150℃which has been improved by0.05.The paper probed into the factors influencing the mechanical properties of compositematerial，such as the proportion of wood fiber and polyester fiber，resin content，foaming agentscontent and density，when using wood fiber and polyester fiber to make composite soundabsorption materials．The study shows that it is feasible to make wood composite soundabsorption materials by wood fiber and polyester fiber. The proportion of wood fiber andpolyester fiber，resin content，foaming agents content and density are the main factorsinfluencing the mechanical properties of composites．With the increase of the proportion ofwood fiber and polyester fiber，the static bending strength and the internal bond strength ofproducts increases．When foaming agents content increases，the mechanical properties ofproducts weaken linearly. When density increases，the mechanical properties of the productsheighten linearly．The sound absorption coefficient of composite materials with wood fiber and polyesterfiber which have been produced by different process conditions were measured using theimpedance tube instrument，this paper studies the effects of the four factors which are theproportion of wood fiber and polyester fiber, resin content, foaming agents content and the density on sound-absorbing performance of the composite material. The results show that: whenthe ratio of wood fiber and polyester fiber is3:1, resin content is12%, foaming agent content is8%and the density is0.2g/cm~3, the composite material has good sound absorption properties.The sound absorption coefficient of composite materials with wood fiber and polyesterfiber under the condition of different structure and different ways of installation measured usingthe impedance tube instrument, this paper studies the effects of the density and thickness aswell as the air-flow resistance rate of the material and the depth behind the composite materialas well as the cover material on sound-absorbing performance of the composite material. Theresults show that: the optimal density of the material is0.2g/cm~3, the optimal the flowresistance rate of the material is1.98×105Pa s/m2; the thickness of the material and the depthbehind the composite material need to adjust according to the using environment; the highfrequency of sound absorption performance of the composite material has been influenced forthe surface decoration material.