| 摘要: | 隨著科技的發展，噪音成為生活中不可避免的潛在傷害，其來源來自交通、工地、工廠以及室內空間所產生之噪音，為了降低噪音影響，吸音材料廣泛的應用於生活空間中。吸音材料為了提中高低頻的吸音效果往往只能增加材料之厚度，但增加厚度不僅使成本上升、重量提高，增加了使用上的限制。為了更有效的的提升材料的低頻吸音性能並兼具使用便利性。本研究針對吸音材料進行製造方法與複合材料對吸音性能的影響，在本實驗中，使用聚乳酸(PLA)及聚偏二氟乙烯(PVDF)開發了一種新型的吸音膜材，研究了以靜電紡絲法製備PLA、PVDF奈米纖維膜，及咖啡粉末複合不織布對吸音性能的影響。
實驗結果表明，PLA於靜電紡絲工程時因溶劑脫出產生呼吸效應，進而於纖維表面產生微細孔洞，在吸音測試中PLA纖維膜因具有較大之孔隙，使聲能於碰撞吸音材後能夠進入材料內部產生黏滯流動損失及內部摩擦兩效應發生，在吸音係數綜合評價(Sound Absorption Average ,SAA)中以PLA作為第一層膜材之數值為0.66而使用PVDF者為0.59，雖說兩者差距不大，但在吸音曲線上可發現PLA複合吸音材較PVDF複合吸音材吸在達到良好吸音材知吸音係數0.6前移一個中心頻率，PLA為400Hz，PVDF為500Hz，故PLA較PVDF之奈米纖維膜在低頻區域時具有較良好的吸音能力，但兩者在中高頻段區皆有良好的吸音性能。
With the development of technology, noise has become an inevitable potential injury in life. Its source comes from the noise generated by traffic, construction sites, factories and indoor spaces. In order to reduce the impact of noise, sound-absorbing materials are widely used in living spaces. In order to improve the sound absorption effect of high and low frequencies, sound-absorbing materials often only increase the thickness of the material, but increasing the thickness not only increases the cost and weight, but also increases the restrictions on use. In order to effectively improve the low-frequency sound absorption performance of the material and also with ease of use. This study focuses on impact on sound absorbing performance of manufacturing and composite material .In this experiment, using polylactic acid(PLA)and polyvinylidene fluoride(PVDF) develop new type of sound-absorbing membrane material ,including the nanofiber membrane of PLA ,PVDF developed by electro spinning and coffee powder composite nonwoven fabric.
The experimental results show that, PLA during the electrospinning process produces a breathing effect due to solvent extraction, and then generates fine holes in the fiber surface. In the sound absorption test, the PLA fiber membrane has large pores, so that the sound energy can collide with the sound absorbing material. When entering the material, two effects of viscous flow loss and internal friction occur. In the comprehensive evaluation of sound absorption coefficient(SAA), PLA the value of as the first layer of film is 0.66 and the use of PVDF is 0.59, although both gap is small, but the curve can be found in the sound absorbing PLA and sound absorbing material than composite PVDF composites to achieve good sound absorbing material in a sound absorbing material absorbing sound absorption coefficient of known 0.6 forward a center frequency, PLA is 400Hz, as 500Hz PVDF, and therefore PLA more PVDF the Chennai Rice fiber membrane has better sound absorption capacity in the low frequency region, but both have good sound absorption performance in the middle and high frequency band region. |
