The Reclamation And Application Research Of Waste Rubber Powder

At present, the reclaimed rubber industry in our country universal existence many problems such as great labor intensity, high energy consumption, serious environmental pollution and so on. It has important practical significance to study on waste rubber resource which the natural resources has been decreased and shortage of energy nowadays.In this thesis, variety reclaiming agent including a novel plants reclaiming agent were applied to reclaimed ground rubber tire, the relationship between the varieties and the content of reclaiming agent, reclaim methods (reclaimed with open mill and extruder), process conditions of reclaim (time, temperature, screw speed) to the reclaimed rubber and its vulcanizates of the structure and performance were investigated. The reclaimed rubber and its vulcanizates were characterized by the scanning electron microscope (SEM). The main results showed as following:(1) Normal temperature process conditions of reclaimed by open mill, as the addition content was less than 15phr, with increased the content of the reclaiming agent, compared to the reclaimed rubber without reclaiming agent, the minimum torque and the maximum torque of the reclaimed rubber were decreased, the acetone extractives were increased. In the same addition content, compared to aromatic oil and coal tar, the scorch time and optimum cure time of the reclaimed rubber by plants reclaiming agent were longer, the acetone extractives were less.(2) Normal temperature process conditions of reclaimed by open mill, as the addition content was less than 15phr, with increased the content of the reclaiming agent, the tensile strength and the tear strength of the reclaimed rubber vulcanizates were increased. The tensile strength and the strength of reclaimed rubber vulcanizates by 10phr reclaiming agent were the best, the equilibrium swelling ratio were the least. In the same addition content, compared to aromatic oil and coal tar, the tensile strength and the tear strength of the reclaimed rubber vulcanizates by plants reclaiming agent were larger, also the elongation at break, the equilibrium swelling ratio were smaller.(3) High-temperature process conditions of reclaimed by open mill, as the temperature range of 40～140℃, with the increased of the temperature, the acetone extractives of the reclaimed rubber tended to increased. While the reclaimed temperature is 80℃, the reclaimed rubber vulcanizates had highest of the mechanical properties, the equilibrium swelling ratio were least. In the same temperature, compared to aromatic oil and coal tar, the mechanical properties of the reclaimed rubber vulcanizates by plants reclaiming agent were better, the equilibrium swelling ratio were less.(4) High-temperature process conditions of reclaimed by open mill, as the reclamation time within 6-15min, with the increased of the reclamation time, the tensile strength and the tear strength of the reclaimed rubber vulcanizates were increased. While the reclamation time is 8min, the reclaimed rubber had the best of the tensile strength and the tear strength, the equilibrium swelling ratio were the least. In the same reclamation time, compared to aromatic oil and coal tar, the mechanical properties of the reclaimed rubber vulcanizates by plants reclaiming agent were better.(5) Extrusion process conditions of reclaimed by extruder, the screw speed and the extrusion temperature have a greater impact of reclamation level of waste rubber powder and the mechanical properties of the reclaimed rubber vulcanizates. While the reclaiming agent is 10phr, within the screw speed 60-80r/min, the temperature of the extruder barrel is 170～200℃, the waste rubber powder had better reclamation, the reclaimed rubber vulcanizates had better of the mechanical properties. With increased the screw speed, the mechanical properties of the reclaimed rubber vulcanizates were lower, the equilibrium swelling ratio were increased. With increased the extrusion temperature, the mechanical properties of the reclaimed rubber vulcanizates had become variation. The equilibrium swelling ratio were increased by elevated temperature of the feed zone or the compress zone in the extruder barrel, decreased by elevated temperature of the metering zone in the extruder barrel. In the same addition content, compared to aromatic oil and coal tar, the mechanical properties of the reclaimed rubber vulcanizates by plants reclaiming agent were better.(6) SEM result showed that, in the same addition content and process conditions of the reclaimed, compared to aromatic oil and coal tar, the surfaces of the reclaimed rubber and the fracture surfaces of the reclaimed rubber vulcanizates had more detailed cross-section, the particles and holes were less.