Properties Study And Preparation Of Organic Silicon Buffer Clay

Silicone elastomeric mastic primarily prepares from by raw materials such as silicones oil,fillers and coupling agents. It as a buffer material is a large number of applications on thevehicle, playing a good damping effect. The shock eliminator which weight is light andoverhaul for a long time is made with buffer clay, therefore polysiloxane as the main material ofthe buffer clay causes boom at home and abroad. But due to raw material monomer limiting atdomestic, the study also stay in the theoretical level and process conditions are not mature, poorstability.Methylphenyl silicone oil has characteristics of a high viscosity-temperature coefficient,low freezing point and flash point, excellent resistance to compression, rapid change ofviscosity under pressure resistance, resistance to low temperature et all. In this paper it isexplored several ways of the buffer clay preparation with methyl phenyl silicone oil. In thispaper, we used by anionic ring-opening polymerization to prepared different phenyl contentand molecular weight methylphenyl silicone oil. And then it is explored for methods of thecontrol molecular weight and the relationship of between viscosity and molecular weight. Itsmolecular structure was characterized by IR, UV, NMR and methyl phenyl silicone oil ofpredetermined viscosity range was obtained by the method. At last it is explored for theinfluence of several fillers addition on performance of buffer clay.In this thesis, the research contents and conclusions as follow:1The experimental process of preparation the methylphenyl silicone oil of the number averagemolecular weight for100000—250000as follows: Under nitrogen environment, first joiningthe DnPhand D4, and then adding the catalyst tetramethyl ammonium hydroxide siliconalkoxide and blocking agent MD₂M.2The influence is very large for the amount and the adding temperature of the blocking agentMD₂M on the molecular weight of methyl phenyl silicone oil. With the increase in the amountof capping agent MD₂M, the molecular weight of methyl phenyl silicone oil will be reduced.The blocking agent MD₂M joined temperature should be controlled at the range of65⁹5℃appropriate.3The different phenyl content and molecular weight silicone oil were synthesized by the anionic ring-opening. With phenyl content and molecular weight of silicone oil increasing,viscosity-temperature coefficient of silicone oil were increased, while the shearing force is alsoincreased.4The adding of the fillers not only reduces the cost of the buffer clay, but also to improves theperformance of the buffer clay. Adding talc, graphite, silica, etc, can be formed a stableprotective film on the surface of the metal buffer, in order to reduce the buffer clay frictionalwear on the metal surface. In this article the kind and amount of the filler was determined byexperimental analysis, the added amount of the fillers is for45%.5Buffer clay was prepared by an open roll mill and Hack torque rheometer. In Hack rheologytests, the balanced torque gradually decreased with the temperature increased under the samerotational speed. This indicates that when the speed is constant and the temperature increases,the intrinsic viscosity of buffer clay gradually reduces. When the temperature is constant, thebalance torque with engine speed increases. This indicates that when the temperature isconstant, the intrinsic viscosity of the buffer clay increases with shear force increasing.