Research On Organizations And Sound Absorption Properties Of Diatomite/Polyurethane Porous Composite Material

With economy developing, noise pollution makes a serious impact on people’s working conditions and living environment. It become probably that diatomite will be made to the sound-absorbing material because of it’s porous structure. Diatomite reserves in China ranks second in the world. In our country, diatomite mainly used for light wall material,but its use is not wide. Research shows that the diatomite has a pore structure characteristics, which makes the diatomite has a larger porosity, strong adsorption, excellent sound absorption properties, wear resistance and heat resistance and other properties. And it also has certain intensity. Diatomite is the quality of heat insulation, fire retardant, sound absorption,humidity and purifying indoor air environmental protection interior decoration materials.The purpose of this paper is to develop efficient sound absorption material and product. A certain strength and flame retardant properties of diatomite/polyurethane composite porous sound absorbing material was prepared by one step foaming method. The relative content, focus ondiatomite and polyurethane foaming agent, opening agent and flame retardanteffect of content on properties and microstructure of composite, especially the influence on the sound absorption properties of composite materials.Through the observation of diatomite/polyurethane composite microstructure with SEM, there is multi aperture communicating channels in composite materials.The pore wall adhereto a large number of diatomite particles who are fine connected with polyurethane.The diatomite particles maintain its open state. With the increase of diatomite content, according to reduction of polyurethane foaming material, it will seriously reduce the formation of gas foaming process.Porosity and average pore size of diatomite/polyurethane composite material will decrease.The research on microstructure of diatomite/polyurethane composite show that the acount of diatomite made the greatest impact on the density and the strength of the composite, while the foaming agent and the opening agent could improve the morphology and porosity properties of the composite material. By changing the amount of diatomite, diatomite/polyurethane composite material density up to0.2g/cm3less compression strength up to24MPa or more; Blowing agent and an amount of the pore openings form the composite obviously affected so greatly affect the degree of diatomite/polyurethane density and strength of the composite material; DMMP was added to a flame retardant composite flame played a significant role when the addition amount of the flame retardant DMMP,20parts of diatomite/polyurethane composite material up to a limiting oxygen index of29.6, the same material than the construction industry flame retardant standards.The study on the sound absorption performance of diatomite/polyurethane composite material shows that, diatomite/polyurethane porous composite material have strength and good sound absorption characteristics. The process formula of absorptiontype diatomite/polyurethane composite the most consistent with the building material:the diatomite in200copies,20copies of opening blowing agent, agent0.2, flame retardant20, the curing temperature is70℃, the curing time is8hours. The process forpreparation of diatomite/polyurethane composites exhibit excellent sound absorption characteristics, the peak absorption coefficient at around0.9, sound absorption coefficient is higher than the frequency range0.56width is greater than2000HZ.