| This thesis studied the formulation design and applied properties of EPDM/CPE blends.How the factors, which are ratio of EPDM/CPE, curing system,reinforcing agent system, softening agent system,and antiagers,affect the physical and mechanical propterties , heat-aging resistance and permanent deformation of the vulcanizates,was investigated. Furthermore, the fracture surfaces of EPDM/CPE blends were explored and its inner structure was analysed by SEM.The results showed that the EPDM/CPE vulcanizates have better physical and mechanical propterties , heat-aging resistance and permanent deformation properties. The best blend ratio is 70/30.Among the studied reinforcing agents, N550 has smooth surface and good structure,so can enhance the strength of blends efficiently. Considering the comprehensive properties of EPDM/CPE vulcanizates,we determine 50 phr as appropriate carbon black dosage.With the increasing of curing time, the hardness and tensile strength of peroxide-vulcanized EPDM/CPE blends increased,and of which the break elongation and permanent deformation reduced .Meanwhile,the hardness of composite curing EPDM/CPE blends increased, the tensile strength increased at first and then reduced,and the permanent deformation reduced .When the pressure is 10MP,the temperature is 150℃,the curing time is 10min, the comprehensive properties of EPDM/CPE blends are the best.Among the studied antiagers,RD can protect the vulcanizates rather well. The protective effect under high temperature can be improved significantly with addition of MB. When the dosage of RD is 2.0 phr and that of MB is 1.0 phr, the protective effect is better.Among the studied softeners, nephthenic oil can improve the synthetical performance of EPDM/CPE blends,and it will be better with addition of DBP.But the compatibility of DBP and EPDM is not better.A litter of DBP will spatter out, which can improve the demould property and surface brightness of rubber hose.But the dosage of DBP can not be too much, the better ratio of nephthenic oil and DBP is 5/3.The physical and mechanical propterties and heat-aging resistance of EPDM/CPE blends will be impoved significantly,using dicumyl peroxide DCP in the peroxide curing system. TAIC can help to initiate free radical , increase the efficiency of cross-linking,and enhance the properties of heat-aging resistance.When the dosage of DCP is 4.0 phr and TAIC is 1.0 phr, the comprehensive properties of EPDM/CPE blends are the best.Using the software of orthogonaie design assistant,we achieved the best combination of A3B3C1D1 of the peroxide cure system,that is ,the blend ratio of EPDM/CPE is 70/30;the dosage of DCP is 4phr;the level of N550 is 50phr;the curing time is 10min.Therefore,the best formula is as follows:EPDM/CPE 70/30,DCP 4.0, N550 50, TAIC 1.0, RD 2.0, MB 1.0, CTP 0.3, ZnO 3.0, MgO 5.0, Stearic Acid 1.0, Coumarone Resin 2.0,Nephthenic Oil 5.0, DBP 3.0.The curing conditions are:Pressure 10MPa,Temperature 150℃,Curing Time 10min.The physical and mechanical propterties of peroxide-vulcanized EPDM/CPE blends with the best formula and composite curing EPDM/CPE blends are better than that of pure EPDM. Compared with it,the composite curing EPDM/CPE blends have better tensile strength and break elongation but poor heat-aging resistance and permanent deformation.Each of two curing systems has its own advantages.So by optimizing the formula and processing technology of EPDM/CPE,the composite curing system should be improved, which can solve the contradiction between mechanical properties and heat-aging resistance,and the comprehensive properties of EPDM/CPE will be better.For this, this thesis discussed it preliminarily ,and it should be further investigated.
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