Microstructure And Properties Of Nitrile Rubber And Preparation Of High-Performance Nitrile Magnetic Rubber

The microstructure of rubber and filler is the key factor that determines vulcanizate’s performance. Magnetic nitrile rubber is made from nitrile rubber, magnetic powder and a small amount of complexing agent, vulcanized into flexible magnetic material. Recently applied research not only pay attention to the magnetic properties of the bonded magnets, and so put forward higher requirements to their physical and mechanical properties and anti-aging properties.This paper investigated the affect of acrylonitrile content and carbon black on the performance of nitrile rubber, on the basis, investigated the affect of factors such as binder, reinforcing agent, plasticizer, coupling agent, antioxidant, vulcanization system in the system of magnetic rubber.Finally the formulation optimized by orthogonal experimental design, and the high-performance nitrile magnetic rubber prepared meet customer requirements.Investigated the influence of acrylonitrile content of nitrile rubber on processing performance, vulcanization characteristics, physical and mechanical properties, the sulfurization reaction, the glass transition temperature, the pyrolysis reaction, the chemical shift and the crosslinking density, the study results show that:As acrylonitrile content increased,the mixing torque increase, but a small amount of carbon black added improve the interaction forces between the molecules, diffece of the mixing torque decreased; vulcanization rate first increases and then decreases, the fastest rate of acrylonitrile content about28%; Tensile strength, increased with the acrylonitrile content increasing, when the the ACN content greater than28%, a significant increased; The acrylonitrile promote the vulcanization, vulcanization behavior diffect with increasing acrylonitrile content; Pyrolysis process, the double bond cross-linking and ACN cyclization exothermic action, peak temperature of the exothermic peak first increases and then decreases; Infrared spectra show that the addition to the C=N stretching vibration absorption peaks are not displaced, the other characteristic peaks of varying degrees of blue shift size as follows:vasCH2> vsCH2>δCH (trans-1,4)>δCH2> gamma (C≡N); Glass transition temperature increases linearly with increasing acrylonitrile content, and a greater degree of influence, physical crosslink density and the total crosslink density increased, the chemical crosslinking density first increases and then decreases.Investigated the influence of carbon black particle size on processing performance, vulcanization characteristics, physical and mechanical properties, the sulfurization reaction, the glass transition temperature,the pyrolysis reaction and the crosslink density of nitrile rubber,study results show that:the carbon black can affect interaction between molecule chains of nitrile rubber, thereby affecting its processing performance; particle diameter of carbon black smaller effect on the vulcanization rate, but because the smaller the particle size,the greater heat accumulated, scorch time and cure time are shortened; Comprehensive physical and mechanical properties of carbon black N330is optimal; Carbon black is less impact on the curing reaction, activation energy is little difference; Carbon black has a stabilizing effect on the nitrile rubber pyrolysis; Effect of carbon black particle size on the glass transition temperature is also smaller; Effect of different particle size of carbon black on its physical crosslinking density is smalle, but as the particle size increases the chemical crosslinking density is significantly reduced.Preparing the effects flowing agent ZN-1, examine a key factor in the magnetic rubber binder, the choice of the magnetic powder, a coupling agent type, dosage and treatment process, the amount of reinforcing agent, results show. Homemade flowing agents can reduce compound hardness,improve the dispersion properties of the magnetic powder, have a certain anti-aging properties; magnetic powder particle size should be small and uniform,the diameter and thickness about3.0-4.0; Magnetic powder treated with titanate coupling agent parts by weight of about1%, and pre-dispersion treatment with high solubility organic solvent, magnetic properties of the magnetic powder is the best; Carbon black as a reinforcing agent, the dispersion properties of the magnetic powder is reduced, so that preferably in small amounts in the case to meet the performance requirements.Investigated by orthogonal design of the impact of magnetic, plasticizers, antioxidants, accelerators, vulcanization activators and uniform flow agents on the strength and performance of magnetic rubber, identified best formula:NBR3470100, BMXF-5S850, coupling agent8.5, plasticizers5, ZnO5, SA2, N33020,RD2, antiager MB1; ZN-17, DM3,S/DCP/TAIC0.5/1.5/2.5. And the optimal formula verificated, the test results are normal and anti-aging performance are good, magnetic properties is excellent, and all aspects of performance in full compliance with the high demands of the customers.