Effects Of Multi-component And Multi-dimensional Nano Fillers On Properties Of Natural Rubber

Using the thermal conductivity of fillers to promote the heat transfer of rubber vulcanization is of great significance to improve the vulcanization efficiency and reduce the production energy consumption.This topic selects a relatively mature tread rubber formula as the research object,and uses different tube diameters,different dosages of multi-walled carbon nanotubes(MWCNTs)and different dosages of graphene oxide(GO)as thermally conductive fillers to explore the effect of the two on the properties of natural rubber,and MWCNTs/GO are used to enhance the properties of natural rubber and determine the best ratio.The temperature field of rubber was simulated and analyzed,and the influence of the addition of thermally conductive filler on the temperature field distribution of rubber during vulcanization was studied.Research indicates:1.As the content of MWCNTs increases,the thermal conductivity of the rubber compound is significantly improved.When the content of MWCNTs is 10Phr,the thermal conductivity of the rubber compound and the vulcanizate increase by 79.2%&73.9%,respectively.The improvement of the thermal conductivity of the rubber compound promotes the vulcanization of the rubber and increases the cross-linking density.When the content of MWCNTs is 6Phr,the positive vulcanization time tc₉₀decreases by 14.5%.At this time,the tensile stress and the tensile strengthof the vulcanized rubber is improved.The smaller the tube diameter of MWCNTs,the more obvious the improvement effect on the thermal conductivity of the rubber compound and the vulcanizate,the more helpful it is to save vulcanization time,and the more obvious the reinforcement effect on the mechanical properties of the vulcanizate.2.As the content of GO increases,the thermal conductivity of the rubber compound continues to increase.When the GO content is 6Phr,the thermal conductivity of the rubber compound and the vulcanizate increase by 51.8%&55.9%;the cross-linking density has increased;GO itself consumes part of the vulcanization accelerator,and the vulcanization efficiency has not been improved.The 100%constant extension stress,300%constant extension stress and hardness of the vulcanizate have been improved,and the tensile strength,tear strength and elongation at break have been reduced.3.The synergy of MWCNTs/GO builds a"thermal conduction channel"between the fillers,and further improves the thermal conductivity of the rubber compound.Compared with a single filler,when the content of MWCNTs and GO fillers are 3Phr and 6Phr,respectively,the positive vulcanization time tc₉₀decreases by 11.35%.At this time,the thermal conductivity of mixed rubber and vulcanized rubber increased by6.1%and 6.5%,respectively.The 100%constant extension stress,300%constant extension stress and hardness of vulcanized rubber increased slightly,and the tensile strength,tear strength and elongation at break were reduced.4.The simulation results of the temperature field during the vulcanization of thick rubber products show that natural rubber itself has poor thermal conductivity,which causes a large temperature gradient in the vulcanization process.MWCNTs/GO synergistically and used in natural rubber can significantly enhance the heat transfer capacity of the rubber,reduce the internal temperature gradient of the rubber,and improve the uniformity of vulcanization.In summary,Starting from the actual application,under the premise of ensuring the mechanical properties of the rubber compound,when MWCNTs and GO are used in conjunction with the addition of 6Phr and 3Phr,the overall performance of the MWCNTs/GO/NR composite obtained is the best.This result provides reference value for the realization of energy saving in the vulcanization process and the application of multi-dimensional nano-fillers in rubber materials.