Study On Preparation And Properties Of ACM/PA Thermoplastic Vulcanizates

Through the dynamic vulcanization technology, we prepared high temperature resistant, oil resistant ACM/PA thermoplastic vulcanizates with acrylate rubber and the ternary nylon, Studied the preparation methods and preparation technology on the influence of the structure and performance of ACM/PA TPV; In the preparation of TPV by using double screw extrusion, the relations between thermal history, curing speed and material residence time are discussed; chosen the suitable constitutive equation for the TPV prepared and calculated the corresponding constitutive equation parameter.The results showed that the dynamic vulcanization time,dynamic vulcanization temperature,molding temperature, shear rate, rubber and plastic ratio and curing system has important influence on structure and performance of ACM/PA TPV. In haake torque rheometer, About 2 min after final torque balance,system achieved thermoplastic vulcanized state; With the increase of dynamic vulcanization temperature, mould temperature and rotor speed mechanical properties have a trend of rise first then fall; mixing vulcanization system and ternary nylon extrusion granulation in twin screw extrusion machine befor dynamic vulcanization, and ACM/PA TPV made by method has the highest performance and stable quality; The performance gap between Three different vulcanization system of TPV is very big, Sulfur/soap vulcanization system has high tensile strength and tensile elongation, and hardness also biggest; When the ACM/PAM15 rubber/plastic ratio is 70/30,the TPV quality performance is best,particle distribution more uniform and had a small particle size, With the increase of content of ternary nylon, TPV energy storage modulus and loss modulus are reduced, tanδ increased; After aging and oil resistant test for TPV at 100 ℃x 72 h, TPV tensile strength and hardness increased,this is caused by the ternary nylon crystallinity; the structure of TPV is different from vulcanizate, its strength mainly comes from the ternary nylon,which is continuous phase. therefore, the reinforcing effect of carbon black and silica to TPV is nothing compared with vulcanizates. After repea ted experiments, an oil resistant, high temperature resistant ACM/PA thermoplastic vulcanizates was prepared.Low feeding speed and the screw rotation speed can extend the resisdence time in twin screw extruder and longer equivalent vulcanization time,which is good for improveing the degree of cure. Under the experimental setting condition, material residence time is 3 min, after adjusting the vulcanization system, t90 at 170 ℃ is 2.5 min, vulcanization reaction activation energy is 91.5 kJ/mol, Reasonable matched curing rate, material residence time and extrusion process can get thermoplastic vulcanizates with outstanding mechanics performance, achieving environmental protection and energy saving, continuous production.Accurately measured TPV stress strain curve, and matched TPV stress strain curve with several widely used hyperelastic constitutive equation,calculatede its parameters,3 order Ogden model describe the ACM/PA TPV stress-strain relationship well, the corresponding parameters is mu 1.011,9.0605,-1.0024;alpha 1.2473,4.1297,1.096; provided basic data and the suitable constitutive equation for the design and application of ACM/PA TPV.