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Sound Absorption Properties of DFs/EVA Composites
Lihua Lyu1, Yingjie Liu2, Jihong Bi3
1School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034, China. lvlh@dlpu.edu.cn.
Polymers
|May 9, 2019
Summary
Discarded feather fibers (DFs) and ethylene vinyl acetate (EVA) create effective sound absorption composites. Optimized DFs/EVA materials achieve a sound absorption coefficient over 0.9 for broad frequency ranges.
Area of Science:
- Materials Science
- Acoustics
- Polymer Science
Background:
- Feather fibers (DFs) are an abundant waste material.
- Ethylene vinyl acetate (EVA) is a versatile polymer.
- Developing sustainable sound absorption materials is crucial.
Purpose of the Study:
- To prepare and characterize DFs/EVA composites for sound absorption.
- To investigate the influence of processing parameters on acoustic performance.
- To establish a quantitative relationship between fractal dimension and sound absorption.
Main Methods:
- Hot-pressing method for composite fabrication.
- Controlling variable method to study parameter effects.
- Transfer function method for sound absorption measurement.
- Box counting method and fractal theory for structural analysis.
Main Results:
- DFs/EVA composites exhibited excellent sound absorption.
- Optimized conditions yielded a sound absorption coefficient > 0.9.
- A wide sound absorption band was achieved.
- Fractal dimension correlated with DFs content and composite density.
Conclusions:
- DFs/EVA composites offer a sustainable solution for sound absorption.
- Fractal dimension provides a quantitative metric for optimizing acoustic design.
- This research contributes to the development of advanced porous sound absorption materials.
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