Study On Noise Reduction Properties Of Polyurethane Rigid Foam

Noise is the third resource of pollution that do harm to environment, to people's healthyand influence the normal use of many instruments, in some instance, it even endanger thesafety of the country. Therefore the noise control and study is not only for the environmentprotection requirement but also for the need of keeping the safety of the country.In the study, the variety rule of the induction noise was studied by means of the noiseinduction testing. Polyurethane foams is one of the most popular noise absorptionmacromolecule porous materials. For the development of the technical of polyurethanesynthesis, polyurethane foams sound absorption materials should keep the pace of newtechnology in this industry. In this study, a new polyether was produced and the factors thatinfluence on the quality were discussed.The noise reducing characteristics of polyurethane rigid foams was tested and theapproach to improve the noise reduction property of the polyurethane rigid foams wasdiscussed. At the same time, three kinds of complex polyurethane materials has beenproduced and the characteristics on noise reduction was also been tested.Main innovation and study results are described as follows:(1) A polyether which containing phenyl in molecule has been synthesized and thepolyurethane rigid foams produced by it as the main materials has good characteristics.(2) Adopting the self-designed noise testing equipment, the noise-reducing property ofpolyurethane rigid foams on the basis of different kinds of polyether and thickness was tested.From the testing result, a set of direction for the best noise reduction effect was built.(3) A polyurethane foams composite reinforced by tiny hollow glass ball has beenproduced and the characteristics on noise reduction have been discussed.(4) Another two composite materials that adhere polyurethane elastomer or polyurethanecoating to polyurethane foams surface have been produced and it noise reducingcharacteristics has been tested. The reasons why the composite material can increase thenoise reduction property have been discussed and bring forward the noise reductionmechanism.