Study On Black Talc Reinforcing Chloroprene Rubber And Its Mechanism

In view of the environmental pollution of traditional rubber reinforcing fillers such as carbon black,the feasibility of black talc instead of carbon black as reinforcing filler for chloroprene rubber(CR)is discussed.Black talc is not only rich in reserves and cheap in price,but also has high thermal stability and excellent reinforcing properties.In this paper,the grinding and modification of black talc and its effect on the mechanical properties of CR were studied,and the strengthening mechanism was analyzed.The main test instruments and characterization methods are laser particle size analyzer,universal tensile testing machine,XRD,ATR-FTIR,XPS and SEM,etc.The specific work is as follows:The effects of grinding and surface modification on the properties of black talc were investigated.The experimental results show that the best grinding time of black talc should be 120 min.Anhydrous ethanol is a good grinding aid for black talc.The best modification effect on black talc is titanate coupling agent NDZ-201.In addition,the relationship between specific surface area(x)and grinding power consumption(W)is W=Aexp(-x/B)+C,A=1.2336,B=-0.074,C= 0.0086.The preparation process of modified black talc reinforcing chloroprene rubber(OBT/CR)was investigated.The experimental results showed that when the amount of modified black talc and modifier were 85 g and 1.5 g respectively,the modification time was 30 min,the amount of DTDM and NA-22 were 2 g,and cured after standing for 24 h,the mechanical properties of OBT/CR was the best.In addition,the crystallinity of the modified black talc decreased from 75.3% to 48.7% after mixing,and rised to 73.81% after vulcanization,which was due to the delamination during the mixing process and the restoration of the crystal structure vulcanization.The performance and structure of pure CR,black talc reinforced CR(BT/CR)and OBT/CR were investigated.The experimental results show that the OBT/CR has the largest torque difference and tensile strength,which are13.94 d N·m and16.56 MPa separately.In addition,the characterization test analysis shows that the modified black talc is combined with CR by physical winding.The storage modulus(E')of OBT/CR is also higher than BT/CR due to physical crosslinking.