Prepartion And Properties Research Of Acoustic Transmission Rubber

Acoustic transmission rubber as the coating material of underwater acoustic equipment components, has very important using value. Because of the complexity of the working environment and requirements of acoustic transmission rubber should not only has good transmission performance, but also has good water tightness, cold resistance, excellent mechanical properties. In this paper, we prepared the chloroprene rubber (CR) and butadiene rubber (BR), casting polyurethane (CPU), mixing polyurethane (MPU) of three kinds of acoustic transmission rubber materials. Using sulfuration apparatus, differential scanning calorimeter (DSC), acoustic pipe, water vapor permeability tester, dynamic mechanical analyzer (DMA) techniques, we research and analysis of the curing temperature, curing time, different rubber ratio, clay dosage on the performance of materials. Main content of this paper as follows:(1) Using accelerator TT and accelerator NA-22 fits low temperature curing of CR, they can effectively shorten the scorch time (T10) and curing time (T90); Using accelerator PZ and accelerator TT and increasing the amount of sulfur fit low temperature curing of BR, they can effectively shorten the scorch time (T10) and curing time(T90); Finally, we designed the low temperature curing formula for chloroprene rubber and butadiene rubber, the curing temperature is120℃, the curing time is 30 minutes.(2) The performance of CR/BR closely related to the proportion of the base rubber. As the CR ratio decreased, the mechanical properties of rubber declined. Using BR into CR, it can effectively reduce the glass-transition temperature, improve the cold resistance of material, at the same time, can also reduce the damping performance of material, improve the acoustic performance, and CR/BR in the temperature range of-2℃ to-30℃, the change of the storage modulus is small, dynamic mechanical performance is relatively stable, suitable for sound transmission rubber material. BR will reduce the water tightness, so we should control the ratio of BR.(3) Casting polyurethane curing at 80 ℃ for 16 hours with good comprehensive properties. The mechanical properties of CPU had a slight increase, the glass transition temperature decreased slightly, cold resistance increased, damping performance declined, acoustic performance improved, especially in the high frequency acoustic performance was better, but the water tightness decreased slightly.(4) Adding the super accelerator PZ can effectively reduce the MPU curing temperature and shorten curing time, it also can realize low temperature fast curing. When adding 2.5 phr PZ, the vulcanization will be completed in 30 minutes at 130℃. Compared to the curing temperature of 150℃,the MPU with the curing temperature of 130℃ had cold tolerance, the mechanical properties and water tightness performance is slightly lower, but the acoustic performance is better. The heat aging resistance performance was poor, it should add antioxidants in the formulation to enhance its heat aging properties.