Preparation And Properties Of Non-vulcanized Butyl Rubber Damping Material

Damping materials are widely used in air conditioning equipment,automotive and other vibration equipment.Rubber is a viscoelastic material suitable for damping material.The rubber was made into a non-vulcanized damping material by a suitable processing method.Compared with other similar damping materials such as asphalt damping materials,hot melt damping materials,coating damping materials,the rubber has many advantages including simple molding,non-toxic and tasteless,friendly environment,to paste and install on a variety of materials and to make a binding damping treatment,and more excellent damping effect,etc.Butyl rubber is an ideal base damping material,including isobutylene-isoprene rubber(IIR),chlorinated butyl rubber(CIIR)and bromobutyl rubber(BIIR).Due to its molecular structure,the molecular segment undergoes a large internal frictional motion when subjected to external vibration or acoustic excitation,and thus rubber exhibits the better damping effect.In the study,we selected IIR,CIIR and BIIR as the matrix materials,diatomaceous earth,light calcium carbonate,talcum powder and mica powder with scaly structure as fillers,carbon black and white carbon black as reinforcing agent.Silica as a variable test,polyisobutylene and terpene resins as tackifiers,and polyisobutylene with a molecular weight of 1300 g/mol and terpene resin as variables were tested.Effect of these on tensile strength,penetration value,peel strength,loss factor and other properties were also studied.Firstly,the properties difference of non-vulcanized rubber damping materials(behind referred to as damping material)of IIR,CIIR and BIIR as basal materials was studied.The results show that the higher the Mooney viscosity of rubber is,the higher the cohesion strength and tensile strength of the corresponding damping material are,and the lower the penetration value of material is.BIIR,which can be prepared damping material,has strong polar group and lower molecular weight and the highest peel strength and loss factor.The vibration damping effect of materials is the best.Secondly,the effect of different filler on the properties of non-vulcanized BIIR damping materials was studied.The results show that the non-vulcanized rubber damping material prepared from diatomaceous earth has the highest tensile strength,but the peel strength and the penetration value are very low.The damping material prepared from talc has lower tensile strength and peel strength,but the loss factor is higher.The tensile strength and peel strength of the damping material prepared from calcium carbonate are higher,but the loss factor is the lowest.The damping material with mica powder has the highest peeling strength,loss factor,and the best comprehensive performance.Thirdly,the effect of the type of reinforcing agents and white carbon black content on the properties of non-vulcanized BIIR damping materials was studied.The results show that The results show that the smaller the particle size,the better the reinforcing effect.Damping material reinforced by carbon black(CB)N330 has the highest tensile strength and peel strength,CB N550 filled damping material followed,and CB N774 filled damping material is the worst.The penetration is just the opposite.Due to the silanol group on the surface of silica,the surface polarity and hydrophilicity of the material is increased.The damping material filled with silica has the highest peel strength,and the tensile strength of that is in between the CB N330 filled damping material and the N550 filled damping material.With the amount of white carbon black increased,the tensile strength of damping material increases.The needle penetration falls,and the peel strength firstly rises and then falls.When the amount of white carbon black is 30 phr,the peel strength reaches the highest value of 68.55 N/25 mm.Hence,white carbon black is more suitable than carbon black for the filler of damping materials,and the optimal dosage is 30 phr.Fourthly,the effect of polyisobutylene with different molecular weight and the content of PIB-1300 on the properties of non-vulcanized BIIR damping material was studied.The results show that with the molecular weight the polyisobutylene increased,the tensile strength of the material increases and the penetration degree decreases.The dampimg material with PIB-2400 has the highest tensile strength and the lowest penetration value.The dampimg material with PIB-1300 has the highest peel strength.When the amount of polyisobutylene PIB-1300 increased,the penetration value and peel strength of the damping material increases,but the tensile strength decreases.When the amount of polyisobutylene is 150 phr,the peel strength is just at the peak of 68.55 N/25 mm,and then peel strength begins to decrease.The peel strength of damping material is the most important because it is used for bonding.And the PIB-1300,the optimal dosage of which is 150 phr,is more suitable for the non-vulcanized BIIR damping materialFinally,the effect of terpene resin contents on the properties of non-vulcanized BIIR damping materials was studied.The results show that the tensile strength of the damping material increases as the amount of terpene resin increases.However,when the content of resin approach to 90 phr,the tensile strength of materials decreases.With the amount of terpene resin increases,the penetration of the damping material decreases,and the peel strength increases.When the adding content reaches 90 phr,the bonding strength strength tends to be stable.In the same test conditions,the loss factor of the damping material firstly rises and then falls with the increase of the amount of terpene resin.When the amount of terpene resin is 90 phr,the loss factor of rubber is the highest.As the amount of terpene resin increases,the peak of the damping material loss factor moves toward high temperatures.When the amount of terpene resin is 90 phr,the overall performance of damping material is optimal.