Study On Application And Modification Properties Of Silicone Rubber Mould

Mould rubber had been widly used in culture stone,optical equipment,communication product,household appliances,automobile parts,toys,etc.Because of its softness and elasticity,the poor dimensional and thermal stablity of mould appeared when it was used.So seeking reinforcing agent with best reinforcement is a research focus in mould rubber.Montmorillonite is a typical expansion layered silicate mineral including the 2:1 structure,and organic cation can be introducde into montmorillonite layers by cation exchange.The characteristics of montmorillonite were expansion,high dispersion,and water absorption etc.It has a feature of plentiful resource,low prices and wide applications.Calcium sulfate whisker is a inorganic whisker and inexpensive but elegant,The dimension,toughness and reinforcement of polymer/CSW composites can be better than that of polymer after the addition of CSW.MQ silicone resin have many advantages,such as high strength,good sticky,lower cost,high temperature and chemical resistance.As reinforced fillers,mechanical properties of mould rubber can be improved apparently.In this research,we attempted to improve the formulas of mould rubber through adding POMMT,OCSW and MQ.The dimension,thermal stablity and service life of mould rubber can be improved by combining excellent properties of filler and elasticity and processing stability of mould rubber.Detailly,our research focused on the three following aspects:Firstly,pillared organic montmorillonite was prepared and applied in addition room temperature vulcanization silicone rubber.The orthogonal test was used in the evaluation of POMMT,BET surface area,FTIR,XRD were used to characterize its structure and properties;POMMT was applied to the mould rubber matrix,and the structure and properties were tested.Results showed that the lamellar structure of POMMT was successfully stripped,specific surface area of it could reach 630m2/g and had excellent thermal stability.The mechanic,mass and dimension thermal stablity of 3%POMMT filled A-RTV had improved in different extent.Secondly,organic calcium sulfate whisker was prepared and applied to C-RTV matrix.CSW was modified by KH560,and SEM,FTIR,XRD,TGA were used to characterize its structure and properties.OCSW was applied to the C-RTV,and the mechanical and thermal properties were tested.The experimental results showed that OCSW could equably dispersed in polymer matrix when 4%of KH560 in CSW;The elongation at break and tear strength of C-RTV/OCSW-1%were enhanced to 655%and 22.37 kN/m,mass and dimension thermal stablity,consistency between OCSW and C-RTV had been improved in different extent.Thirdly,MQ silicone resin was applied in C-RTV.C-RTV/MQ mould rubber was prepared by adding different percents of MQ in C-RTV matrix,and the mechanical and thermal properties were tested.Result showed that the tensile and tear strength of 3%MQ filled C-RTV increased about 12.8%and 7%,and the mass and dimension thermal stablity had been improved in different extent.