Study On Puncture Invagination Of Pharmaceutical Synthetic Polyisoprene Gasket In Clinical Use

Nitrile butadiene rubber（NBR）has been widely used in rubber industry because of its oil resistance,solvent resistance,electrostatic conductivity and other properties.However,NBR is limited in vulcanization and dynamic application of large thick products due to its fast dynamic heat generation and slow heat transfer.In this paper,the effect of aluminum powder and graphite on the processing properties,physical and mechanical properties,oil resistance and thermal conductivity of NBR rubber was studied.The effects of the morphology,amount of aluminum powder,modifier phenolic resin 204 and curing agent H on the properties of NBR compound were studied.The results show that the aluminum powder with spherical structure is better than the aluminum powder with sheet structure to improve the thermal conductivity and oil resistance of rubber,but the fluidity and mechanical properties of rubber are poor.The addition of sheet aluminum powder makes the fluidity of NBR rubber become worse,the tensile strength and tear strength of vulcanized rubber decrease greatly,the elongation increases,but the thermal conductivity and oil resistance increase,and the thermal conductivity increases with the increase of the amount of aluminum powder.When the amount of aluminum powder is more than 80 parts,the thermal conductivity and oil resistance of rubber material increase slowly.Phenolic resin 204 has a plasticizing effect on NBR compound,which can improve the fluidity of the compound and increase the elongation of the NBR compound.It has little effect on the tensile strength,tear strength,hardness and thermal conductivity of the vulcanized compound,and reduces the oil resistance.The addition of curing agent H can improve the hardness,tensile strength and tensile stress of the adhesive properly,and the thermal conductivity is slightly reduced,and the oil resistance is slightly improved.The effects of graphite and two kinds of carbon black and graphite and N330 carbon black on the properties of NBR compound were studied.The results show that among the thermal conductivity fillers N330,N660 and graphite,the thermal conductivity of graphite is better than that of N330 and N660 carbon black,and the temperature has little effect on the thermal conductivity of rubber.The oil resistance of graphite filler is slightly worse than that of carbon black filler.The physical and mechanical properties of graphite filler are poor.When the total amount of filler is constant,the thermal conductivity of rubber material is maximum when the ratio of graphite and carbon black is 60/60.With the increase of graphite coiling dosage,the coking time and curing time are prolonged,and the maximum and minimum torques decrease.The tensile strength,fixed elongation stress,tear strength,hardness and wear resistance of the compound showed a decreasing trend,while the elongation at break and springback showed an increasing trend.There is little change in the oil resistance of the adhesive.The effects of graphite dosage,graphite and carbon black,variety and dosage of coupling agent on the properties of NBR compound were studied.The results show that the thermal conductivity increases with the increase of graphite content,and the increase of thermal conductivity increases with the increase of graphite filling amount.The oil resistance of the compound increases slightly with the increase of graphite dosage.The tensile strength,elasticity and wear resistance of the compound decreased with the increase of graphite content,hardness and fixed elongation increased,tensile elongation first increased and then decreased,and tear strength had little change.The use of coupling agent can improve the mechanical properties of the compound.Among the three coupling agents,si-69 has better comprehensive properties than Zr-202 and KH550.The effects of the three coupling agents on the thermal conductivity and oil resistance of the compound are not different.When the amount of Si-69 is 2.4 parts,the mechanical properties of the compound are better.With the mechanical properties of the compound are better.With the increase of si-69 dosage,the thermal conductivity of NBR compound decreases slightly.