Modification Of Silicone Rubber By Mesoporous Silica And Sound Absorption Property

With the higher requirement of acoustic environment, sound absorbing materials become more important in the field of noise control. Silicone rubber is expected to be applied in the field of noise control due to its better sound absorption. In this thesis, we used silica as sound absorption additives of silicone rubber, because silica is a good strengthening agent of silicone rubber, with the sol-gel method, and hexadecyl trimethyl ammonium bromide as the template agent. We prepared series of silica with tunable pore size from1.87nm and5.56nm by changing the reaction conditions. Finally, we prepared silicone rubber of mesoporous silicas as sound absorption additives and studied the effect of pore size and contents to sound absorption of silicone rubber. Scanning electron microscopy, transmission electron microscopy, N2adsorption desorption analysis methods were used to characterize the samples of silica and got a conclusion that different reaction conditions can get series of silicon dioxide with different pore size, different particle size and different morpHology. Smaller pore size silicas can be prepared with increasing the ratio of TEOS to CTAB. But higher aging temperature only had a certain influence on particle morpHology. Solvents system had more influence on the silica, with anhydrous ethanol and deionized water as co-solvent, particle size reached300nm to500nm, but their pore size only1.87nm. Mesoporous silica had a significant effect on sound absorption of silicone rubber, mainly concentrated in the range of1000Hz to5000Hz, the sound absorption coefficient can be increased to0.84, and maximum sound absorption coefficient move to the low frequency with increasing pore size. Silicone rubber had better sound absorption companying with the adding amount of MS-3from3pHr to10pHr, when the adding amount was8pHr, the maximum absorption coefficient reached0.84.