| 초록 |
In the automobile industry, polyurethane foams are importantly used to absorb negative sounds because of their porous structure. A bubble-like cell contains air, and the air reduces sound energy by friction and heat. Also, the wall of cell decreases the energy by vibration after the sound crashes. To improve these sound absorption property, wood fiber was added into polyurethane composite foam. Moreover, the chemical treatments with alkalization and silanization using sodium hydroxide and 3-aminopropyltriethoxysilane. From FTIR, the chemical treatment was checked by observing specific functional groups (OH, NH2, CH2, and etc.). Using SEM, morphology effect was analyzed through measuring sizes of pores and cavities. Also, DMA was used to analyze damping effect of polyurethane composite foams with chemically treated wood fibers. |
