Study On Blending Modification And Application Of Epoxidized Butyl Rubber

Epoxidation modification is an economical and practical chemical modification method for rubber materials.Epoxidized butyl rubber(EIIR)has been prepared by epoxidation of isoprene units on IIR main chain.EIIR has excellent performance characteristics of both epoxidized modified rubber and butyl rubber,but its application prospects are limited due to its limited cross-linking points and low vulcanization activity.To expand the application of EIIR,we prepared high-performance BIIR/EIIR blends,ENR/EIIR blends,and NR/ENR/EIIR ternary blends by blending EIIR with BIIR,ENR,and NR through physical blending methods.The obtained blend materials had excellent air-tightness,aging resistance,damping and vibration reduction performance,and fatigue resistance.The main work of this paper is as follows:(1)Through premixing of EIIR/MAH,BIIR/EIIR blend materials with different proportions of EIIR were prepared by physically blended methodusing EIIR/MAH masterbatch.With the increase of EIIR dosage,the crosslinking density of BIIR/EIIR blend decreases,the scorching time shortens,and the vulcanization rate accelerates;the tensile strength and tear strength slightly decrease,while the airtightness and aging resistance remain basically unchanged.The effective damping temperature range of the blend material is widened by 14.5 ℃,and the damping performance is significantly improved in room and high temperature regions.It can be used to prepare high damping rubber materials with wide temperature range.(2)ENR/EIIR blend materials with different proportions of EIIR were prepared by physically a blending of d EIIR with ENR.Increasing the amount of EIIR results in a shortened scorch time,accelerated vulcanization rate,reduced tensile strength,tear strength,and resilience of ENR/EIIR blend materials.The material’s heat aging resistance,low permeability,and damping and vibration reduction performance are significantly improved.The aging coefficient increased by 36.6%,the permeability coefficient decreased by 2/3,and the effective damping temperature range widened by 14.5 ℃in comparison with those of ENR.EIIR can be physically blended with ENR to prepare a wide temperature range damping material with high weather resistance and air tightness.(3)NR/ENR/EIIR blend materials with different blending ratios were prepared by physically blending of EIIR,ENR,and NR..The addition of ENR and EIIR leads to an increase in cross-linking density,an extension of scorch period,a decrease in mechanical strength and rebound performance,and an improvement in air tightness and damping of NR/ENR/EIIR blend materials.The addition of ENR leads to a decrease in the heat resistance,air aging resistance,and flexural fatigue resistance of NR/ENR/EIIR blend vulcanizates;Compared to ENR,EIIR not only significantly improves the heat resistance to air aging and flexural fatigue performance of NR/ENR/EIIR blend vulcanizates,but also has more advantages in improving the aging resistance,air tightness,flexural fatigue resistance,and damping and vibration reduction of the blended materials.Among them,compared to pure NR system,the aging coefficient of NR/EIIR(blending ratio 80/20)material increases by49%;the permeability coefficient of NR/ENR/EIIR(60/10/30)blend material is reduced by 93%,effectively damping the temperature range(tanδ > 0.3)expands by 10.2 ℃,effectively damping the temperature range moves towards high temperatures;the first level bending fatigue is increased by about 2.6times,and the resistance to crack initiation is significantly improved.It can be seen that EIIR has good application prospects in the fields of rubber modification and damping vibration reduction.