Preparation And Properties Research Of Polyaniline/Rubber Composites

As a kind of conductive polymer,polyaniline has excellent stability and conductivity,and is one of the more widely used polymer materials.In order to meet the needs of social development,various polyaniline composite materials with excellent properties came into being.The oxidant selected in this paper is ammonium persulfate and the doping acid is hydrochloric acid.The polyaniline doped with hydrochloric acid was prepared by in-situ polymerization,and it partially replaced carbon black N330 or Silica as NR and SBR Reinforced fillers were prepared by mechanical blending method.Vulcanizates with different filler ratios were prepared,and the samples were analyzed for vulcanization characteristics,micro-morphology and physical and mechanical properties.The main conclusions are as follows:Polyaniline/carbon black N330/NR and polyaniline/Silica/NR composite rubber compounds are prepared by mechanical blending.Polyaniline is used together with carbon black or Silica as a reinforcing filler for NR(polyaniline/carbon black N330(wt%/wt%)=0/50,2/48,4/46,6/44,8/42,10/40;polyaniline/silica(wt%/wt%)=0/50,2/48,4/46,6/44,8/42,10/40).Polyaniline played a role in extending the scorch time and shortening the positive curing time of the compound in the two composite systems.When the amount of polyaniline was 4 parts,the two groups of vulcanized rubber reached the maximum crosslink density.By observing the cross-section of the vulcanized rubber sample,it was found that 4 parts of polyaniline can maintain good dispersibility in NR.The test results of physical and mechanical properties show that the mechanical properties of the two groups of composite materials increase first and then decrease with the increase of the amount of polyaniline,which is the best when the amount of polyaniline is 4 parts.The experimental results prove that when the amount of polyaniline is 4 parts,the performance of polyaniline/carbon black N330/NR and polyanil-ine/silica/NR composite compound reaches the best.Keeping the above fillers and proportions unchanged,a composite material of polyaniline/carbon black N330/SBR and polyaniline/silica/styrene butadiene rubber was successfully prepared by mechanical blending.In the polyaniline/carbon black N330/SBR composite material,the scorch time of the rubber compound is significantly prolonged.The positive curing time is first extended and then shortened with the increase of the amount of polyaniline.When 6 parts of polyaniline is added,the crosslinking density of the cured rubber reaches the maximum.In the polyaniline/silica/SBR composite material,polyaniline can shorten the scorch time and positive curing time of the compound at the same time,and the effect of improving the apparent crosslink density is not obvious.The microscopic morphology observation results prove that polyaniline and carbon black N330 can be well dispersed in SBR when used together,while the filler dispersion effect is not good when polyaniline and silica are used together.The test results of physical and mechanical properties show that when the amount of polyaniline is 4 parts and 2 parts respectively,the polyaniline/carbon black N330/SBR and polyaniline/silica/SBR composites can have the best mechanical properties.In this study,the volume resistivity of all samples was measured,and it was concluded that after the treatment,the electrical conductivity of the composite compound changed,and the volume resistivity of the material would decrease as the polyaniline doping continued to increase.When the amount of polyaniline is 10 parts,the volume resistivity of the composite material can be reduced by about 1 to 2 orders of magnitude.Therefore,polyaniline can play a certain antistatic role in the composite system.