Preparation Of Polyaniline Modified Silicon Dioxide Composite And Study On Reinforcing Properties Of Hydrogenated Nitrile Butadiene Rubber

As an important elastic material necessary for the development of human society in the new century,rubber has been widely used in daily life,aviation,national defense and other fields.In recent years,with the development of science and technology,the demand for high performance rubber materials is becoming more and more urgent.The mechanical properties of rubber matrix can be greatly improved by reinforcing filler.White carbon black has the characteristics of fine particles,porous,large specific surface area,and does not depend on fossil energy,so white carbon black is increasingly widely used in rubber reinforcement.However,there are many hydroxyl groups on the surface of Si O₂,which are easy to condense in the rubber matrix,thus affecting the performance of rubber.Therefore,it is particularly important to improve the dispersity of silica in rubber.In this paper with white carbon black as the main body reinforcing filler,hydrogenated nitrile rubber（HNBR）as the rubber matrix,through the different structure of polyaniline（PANI）and polyaniline-modified carbon nanotubes（PANI-CNTs）on Si O₂ composite filler,reinforcing composite filler hydrogenated NBR rubber composites,the composite filler and rubber composites were characterized test and performance analysis.The main research contents are as follows:1.Fibrous PANI was prepared by chemical polymerization,Si O₂ was grown on its surface to obtain Si O₂-PANI composite filler,and Si O₂-PANI/HNBR composite material was obtained by mixing Si O₂-PANI into HNBR.The influence of PANI mass fraction in Si O₂-PANI on Si O₂-PANI/HNBR packing network and the influence of Si O₂-PANI composite packing on mechanical properties of HNBR were studied.The reinforcing mechanism of composite filler was analyzed.When PANI:Si O₂=2%and filling amount is 30 phr,Si O₂-PANI/HNBR tensile strength is 30.31 MPa and tear strength is 26.7 k N/m,which is 129.4%of that of pure Si O₂ reinforcement filler under the same number.The Hardness and elongation at break of Shaw A are both increased.2.PANI was grown on Si O₂ surface by in-situ polymerization.The effects of Si O₂@PANI packing with different mass ratios of Aniline（ANI）on mechanical properties of HNBR were studied.When Si O₂:ANI=50:2,the composite material has the best mechanical properties.The tensile strength of Si O₂@PANI/HNBR is 28.33 MPa.The tearing strength increased from 21.4k N/m to 30.7 k N/m,and the elongation at break and Shore hardness A increased slightly.3.Polyaniline-coated carbon nanotubes（CNTs@PANI）were prepared by in-situ polymerization.Si O₂ was grown on CNTs@PANI by electrostatic self-assembly to prepare Si O₂-CNTs@PANI three-phase packing with different mass fractions.PANI coating effectively reduced the self-entanglement of CNTs,CNTs@PANI could reduce Si O₂ agglomeration and improve its dispersion in HNBR,and the rubber filler network was weakened.When the mass ratio of ANI:CNTs=1:1,the mass fraction of CNTs@PANI is 1%,and the filler fraction of Si O₂-CNTs@PANI is 30 phr,the tensile strength of Si O₂-CNTs@PANI/HNBR reaches 31 MPa,which is increased by 92%compared with Si O₂/HNBR.And the permanent tensile deformation of Si O₂-CNTs@PANI/HNBR is reduced to 8.96%.