Influence Of Biir Synthetic Chemical Agents On Its Application In Inner-linner Compound

Brominated butyl rubber(BIIR)is isobutene-isoprene copolymer elastomer containing active bromine.It is widely used in radial tire,inner tube,container liner,medicine bottle stopper and machine liner,etc.It is an irreplaceable raw material for the innner liner layer of passenger car radial tire.The synthetic chemical agents of brominated butyl rubber mainly include bromine monomer,antioxidant,epoxy soybean oil and calcium stearate,etc.The types and dosage of various chemical agents influence on main structure of brominated butyl rubber directly and have a significant influence on its application in the innner liner layer of passenger car radial tire.In order to study the influence of synthetic macromolecule structure and composition on the application,so as to realize the molecular design and development for different applications,this paper studies and analyzes the synthesis chemical agent of brominated butyl rubber and the application in the formulation of innner liner layer of passenger car radial tire.The main work carried out is as follows:In the first part,the structure and properties of brominated butyl rubber prepared with different amounts of epoxy soybean oil were studied.The experimental results show that the adding amount of epoxy soybean oil change effect on brominated butyl rubber synthesis technology slightly,preparation of brominated butyl rubber microstructure change is less,but it has significant effect on the vulcanization characteristics in the air barrier formula application,significantly reduce the curing rate of passenger car radial tire inner liner,and show positive correlation within the scope of the test.The aging resistance of the air-tight layer can be improved by increasing the addition of epoxy soybean oil,but the air permeability can be slightly improved.Therefore,appropriate amount of epoxy soybean oil can help to improve the service life of the innner liner layer and ensure the safety of the tire.For passenger car radial tire innner liner layer,the most reasonable addition amount of epoxy soybean oil is 1-1.5wt%.In the second part,the effect of the amount of bromine monomer on the structure and properties of BIIR rubber was studied.The results shows that the content of bromine monomer has a great influence on the microstructure of brominated butyl rubber,but had a great influence on the vulcanization,mechanical properties and aging resistance of air-tight rubber.When it is used in the innner liner layer of passenger car radial tire,the addition of 0.9wt%bromine monomer is the precondition to ensure the comprehensive performance of the compound.In the third part,the main work is to study the influence of calcium stearate dosage on the formulation property of inner liner layer.The results show that the vulcanization time is prolonged and the maximum torque and torque difference are slightly increased when the dosage of calcium stearate is increased.The content of calcium stearate should be kept below 3.6%to ensure that brominated butyl rubber in the passenger car radial tire inner liner layer formula when the application of low permeability,high gas retention.An increment of calcium stearate does not change the subject structure of brominated butyl rubber,but help ensure hot oxygen aging property of brominated butyl rubber raw rubber and the mechanical properties of passenger car radial tire inner liner application retention,but brominated butyl rubber application in gas retention.The amount of calcium stearate addition in brominated butyl rubber shall be kept between 1.8 to 2.5%.Combined with the above analysis,brominated butyl rubber bromine monomer content 0.9 wt%,calcium stearate content 1.8-2.5wt%and epoxy soybean oil content 1-1.5wt%applied in the innner liner layer of passenger car radial tire can achieve the formula of innner liner layer with comprehensive processing properties,mechanical properties and aging resistance.