Preparation And Properties Of Sound Absorbing And Flame Retardant Fiber Composites

In recent years,with the acceleration of urbanization and the continuous improvement of living standard,people's awareness of environmental protection has gradually strengthened,and more and more attention has been paid to the problems of noise pollution and fire safety.Consequently,the performance requirements for building materials have also increased.Sound absorbing and flame-retardant fiber composites,which can be used with perforated ceiling,as well as a sealing material in a variety of buildings.Compared with the imported products,domestic products have some defects such as large tightness,poor flexibility,sound-absorbing and flame-retardant properties.In order to narrow the gap with imported products,this paper mainly studied the preparation process and performance optimization of the fiber composites,and the effects of adding components on the properties of fiber composites.It is very important for noise pollution control and fire resistance to successfully prepare the fiber composites with excellent sound absorption and flame retardancy.In this paper,glass fiber,softwood fiber,and poplar chemical mechanical pulp(APMP)were used as raw materials to prepare the high-bulk fiber composites by wet forming-process,with the addition of binder,plasticizer and flame retardant through dipping method.The results showed that the synergistic effect of APMP pulp and plasticizer was helpful to improve the bulk and reduce the tightness of fiber composites.However,it will lead to the decrease of tensile strength of fiber composites.When the content of APMP was 20%,the mass fraction of macerate binder,plasticizer,flame retardant were 2%,1.5%,4%,respectively.Under this optimal preparation process,the tensile strength of the fiber composites was 14.8 N/15mm,the porosity was 80.14%,the content of flame retardant was 11.63%,the carbonization length was 35 mm,the flame retardant effect could reach the level 1 flame retardant standard,and the sound absorption coefficient up to 0.78.Using glass fiber and softwood fiber as raw materials,and the thermal expansion microspheres were added to the fiber composites by adding in the slurry during the wet process.Then the wet-paper was impregnated with a certain amount of binder and flame retardant to prepare the high-foaming sound absorbing and flame retardant fiber composites.The foaming process and the effect of the content of the thermal expansion microsphere on the properties of the fiber composites were studied.It was found that the higher content of the thermal expansion microspheres in the fiber composites,the higher the bulk,which was consistent with the change in grammage and porosity.On the contrary,the tensile strength of fiber composites obviously declined with the microspheres content increasing,which indicated that the thermal expansion microspheres had a negative impact on the mechanical properties of materials.Moreover,the flame-retardant performance of fiber composites were slightly reduced.When the amount of thermal expansion microspheres was 20%,the bulk of the fiber composite was 6.65 cm3/g,the tensile strength was 16.05 N/15mm,the porosity was 85.95%,the flame retardant effect could reach the level 1 flame retardant standard.The fiber composites had resonance absorption peaks at 1250 Hz and 5000 Hz and the sound absorption coefficients were 0.80 and 0.82,respectively.Basalt fiber and softwood fiber were used as raw materials to prepare the sound absorbing and flame retardant fiber composites by wet-forming process.The effects of mineral fiber dispersion,moisture content of wet paper,binder and flame retardant dosage on the properties of fiber composite were studied.It was found that the dispersity of basalt fibers was the best when the dosage of dispersant was 0.006%.When the ratio of softwood fiber to basalt fiber was 7:3,the dryness of wet paper was 30%,the mass fraction of impregnating binder and flame retardant were 6%and 4%,respectively.The tensile strength of fiber composites was 15.5 N/15mm,the porosity was 75.60%,the content of flame retardant was 11.63%,the flame retardant effect could reach grade 1 flame retardant standard,and the highest sound absorption coefficient could reach up to 0.84.