| With the rapid development of auto industry, the discharge quantity of waste tires has been sharply increasing year by year. The recycling of waste rubber has already become a research hotspot of many countries in the world. In this thesis, waste rubber powder (WRP), which was grinded from waste tires, was modified and prepared into damping materials. This process could not only dispose waste tires effectively, but also control vibration and noise pollutions. Furthermore, benefits of economy, environment and society could be obtained.In this thesis, WRP was modified by the method of organic small molecule hybrid: adding hindered phenol AO-60, and a hybrid pad with high damping properties was prepared. The properties of hybrid WRP/AO-60pad were characterized by DMA SEM、XRD、DSC、FT-IR. The main results of this thesis are as follows:(1) The processing technology of hybrid WRP/AO-60was researched, and the process of blending WRP with AO-60was adjusted. In consideration of the processing characteristics of WRP and AO-60, a prior agitation was carried out in stead of the traditional mastication process. In order to get vulcanization agents a better separation effect, a specific mixing procedure was performed.(2) The damping properties of the hybrid pad were characterized by DMA. The influence of AO-60on the damping properties of the hybrid pad was emphatically investigated. The DMA results indicated that, the process of organic small molecule hybrid modification could increase the value of loss factor (tanδ) peak of the hybrid pad prominently from0.366to0.885. With the increasing of AO-60content, the tanδmax value of the hybrid pad gradually increased, the storage modulus in glass state improved, and it could obviously adjust the corresponding peak temperature to gradually shift toward improving direction.(3) The microstructure, crystal habit, thermal behavior and hydrogen bonds existence of the hybrid were characterized by SEM, XRD, DSC and FT-IR. The analysis indicated that, AO-60had good compatibility to the matrix WRP. Most of the AO-60was dissolved in an indefinite form, only a few AO-60congregated in type β crystal form, and the whole hybrid presented an uniform area with microscopic separation. FT-IR scan showed that, there did exist large numbers of hydrogen bonds in the hybrid. Analysis, due to the good compatibility of WRP/AO-60, AO-60could infuse the vulcanization network and form hydrogen bonds with it. So that the structure of the vulcanization network was strengthened, and the damping properties of the hybrid pad were improved.(4) The influence of particle size of the matrix WRP on the damping properties of the hybrid pad was studied. The result showed that, when using60mesh WRP as matrix, the damping properties of hybrid WRP/AO-60pad was the best in this thesis, and the tanδmax value was0.784at temperature of53.6℃(5) A study on the influence of vulcanization conditions on the damping properties of the hybrid pad was made. The result showed that vulcanization temperature, vulcanization pressure and vulcanization time also had a certain impact on the damping properties of the hybrid pad. The appropriate vulcanization conditions of hybrid WRP/AO-60pad in this thesis were145℃, lOMPa,20min.(6) A thorough study on the influence of vulcanization system on the damping properties of the hybrid pad was made. The contrast result showed that, the tanδmax value of the hybrid pad with DM/TMTD vulcanization system was the biggest. A further study on varied vulcanization agents of the hybrid pad in DM/TMTD system was made by the method of orthogonal experiment. The extreme difference analysis showed that, impact factors of vulcanization agents were quite low. The contributions of main factors in vulcanization system were:S>TMTD>DM>DOP. The best formula of vulcanization system of hybrid pad in this thesis was:S2.5phr, TMTD0.1phr, DM0.4phr, DOP8phr, ZnO3phr, CZ0.1phr, SA2phr. |
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