Research On Dynamic Mechanical Properties Of Carboxy Nitrile Rubber With Modified Talcum Powder

Nowadays,the viscoelastic damping material is the main part of the damping structure parts in the production and life.With the application of it,damping form become diversified,field is more extensive,and the effect of vibration and noise reduction is more remarkable.Recently,rubber damping materials have been studied in depth.They are characterized by simple preparation process and various special functions.Fillers is one of main factors to influence the performance of rubber damping material.Carbon materials such as carbon black and graphene are widely used as fillers.However,there is few of studies on talcum?Talc?,which with low price,high impact resistance and high glossiness.All the fillers are faced with difficulty to disperse in organic matrix.To deal with this problem,the research modified the surface of Talc with different modifiers based on technology of surface modification.By that,it realized good dispersion of Talc and higher mechanical properties of rubber damping materials with the fillers.Further more,we explored the modified effect and mechanism of modifiers with different structures and properties.It has important reference value and guiding significance for practical engineering application.In this thesis,the micromorphology,chemical composition and modification mechanism of the Talc fillers were tested by settlement stability test,water contact angle?CA?,scanning electron microscope?SEM?,Fouriertransform infrared spectroscopy?FTIR?and X-ray photoelectron spectroscopy?XPS?.SEM,universal tensile test machine,dynamic mechanical performance analyzer?DMA?and impact wear tester were used to analysis carboxy nitrile rubber?XNBR?and polyurethane?PU?blend with modified Talc and study on filling properties of the fillers.The main accomplished research contents and chief conclusions are as followed.1.Mechanism and effect of modifier type on dispersion of TalcTiO₂ was well adhered to surface of Talc to form Talc@TiO₂ by ball milling after modified with silane coupling agent KH550,titanate coupling agent NDZ201 and water-soluble macromolecule PAAS.The dispersion and mechanism of composite fillers was characterized by CA,SEM,FTIR and XPS.It indicates that the surface of TiO₂ modified by NDZ201 has achieved organic and enhanced hydrophobicity of Talc@TiO₂,which get a stable dispersion in organic solvents.Fillers with PAAS achieved the stable dispersion as electronegative modifier adsorbed on the surface of particles and repelled each other in the solution,not the surface organic.However,fillers with KH550 lacked of dispersion stability as hydrolysis of the modifier.2.Filling amount and type of modifiers effect on properties of XNBR materials.Filling amount and type of modifiers are the main factors on filling performance of modified fillers.In this thesis,effect of frequency response,thermal dynamic mechanical properties,tensile properties,impact resistance and aging resistance of XNBR and XNBR/PU were tested to explore the influence of different Talc@TiO₂ as fillers.It indicates that in a certain range,the storage modulus and impact resistance of XNBR improved with the increase of the filling amount,and the tan?and glass transition temperature decreased at the same time.Pyrogenation lead to disappearance of damping besides high filling group while oil immersion does not.For XNBR/PU blend,the addition of fillers helped to enhance the mechanical properties of the matrix until it reached 15wt%as Talc@TiO₂ was ejected by pressure to form holes in the matrix.For that,it should be in the range of 10wt%¹5wt%when the matrix was filled with modified Talc@TiO₂.In contrast,fillers with PAAS groups performed better mechanical properties than those of KH550 and NDZ201 was a little better than those without modifier.The oil and heat resistance were better shown in KH550 groups and PAAS groups.The effective volume of fillers was increased due to its improvement of dispersibility in the matrix,and the desired damping performance can be achieved with a relatively small amount.