Study And Research On Acoustic Properties Of EPDM Rubber Composite Materials

Sound-absorbing material has become the focus of related research in the field. Since the rubber has very good characteristics of visco-elastic, the properties of acoustic noise for rubber-based composite material are a major research direction, and have the widespread application in many domains. As a general-purpose rubber material, ethylene propylene diene monomer (EPDM) has many advantages, such as small density, cost-effective, excellent heat resistance, weather aging resistance, ozone-aging performance and so on. Used EPDM as a matrix, and adding ADC, glass fiber, the rubber foam materials and the glass fiber-reinforced rubber composite materials are made to reach the rubber material sound absorption and reduction noise performance.Through researching about EPDM rubber foam materials, it is found that vesicant content, foaming temperature and foaming time remarkable affect sound absorption coefficient and sound insulation. The results show that when the vesicant content of 1%, foaming time for 8 min, foaming temperature of 150℃, and the test specimen weight for 20g ,the sound performance is the best result.In order to meet the rubber-based compound materials in the mechanical performance requirements, the glass fiber /EPDM rubber are developed which base compound materials and obtain compound materials in good mechanics aspect performance, and fine noise reduction performance. Firstly, the thermo-compression condition to the compound materials influence is discussed. When the hot-pressing temperature for 90℃, hot-pressing time for 5min, pressure for 15MPA, the compound materials have the best sound performance through orthogonal experiment. Under such condition, we make a variety of system-reinforced composite materials. As a result: when the glass fiber length of 5mm, the content of 5%, acoustic properties of composite materials is the best. On the base of this, by adding foaming agents, further study of the fiber-reinforced foam compound materials, and discussed the processing conditions on the impact of composite materials. The results showed that: the foaming agent content is biggest influence to compound material acoustical property. The second is weight of the test specimen. The glass fiber content is smallest influence. When the glass fiber for 5mm, Glass fiber content of 5%, the vesicant content of 2.5%, fiber-reinforced foam composite materials to enhance the acoustic performance. In order to get better acoustic properties, vesicant ADC5# is needed for more. It is mainly because that the addition of glass fiber plays a negative role in the foaming process of vesicant.