| Anionic living polymerization was widely used, especially in preparing polymer with complicated structure. In this paper, linear and star-shaped rubber L/S-(PI)n-(PSB)n, S-(PB)n-(PSB)n was synthesized with n-BuLi as initiator, THF, PMEDTA,SDBS and TFEE as polar additive, and DVB as coupling agent to get a new style rubber with high performance and properties.Three different coupling agents including m-divinylbenzene, p-divinylbenzene and mixture of two isomers were used to synthesize star polymer to get high coupling efficiency. The results indicated:the seriation of coupling efficiency of different isomer was:m-DVB>DVB>p-DVB, and that of m-DVB could approach 92%; the seriation of average arm numbers was:p-DVB>DVB>m-DVB. The coupling efficiency increased first with temperature, then decreased, the feasible temperature was 50℃. The coupling efficiency increased sharply first and then smoothly when [DVB]/[Li] increased from 1 to 5.The coupling efficiency reduced with increasing molecular weight per arm.Linear block copolymer L-(PI)n-(PSB)n and star-shaped miktoarm S-(PI)n-(PSB)n to improve the compatibility of natural rubber and styrene butadiene rubber blends. The results show that NR/ESBR blend with Linear block copolymer L-(PI)n-(PSB)n or star-shaped miktoarm S-(PI)n-(PSB)n have better dynamic properties:tanδat 0℃reached to 0.297, tanδat 60℃was below 0.156, It indicated that L-(PI)n-(PSB)n and S-(PI)n-(PSB)n increased the compatibility of NR/SBR blend. Star-shaped miktoarm rubber S-(PB)n-(PSB)n was synthesized at the first time. The results show that the polymer have two glass transition temperature which indicates microdomain seperation of PB and PSB. And it has optimal comprehensive properties:elongation at break> 480%, tensile strength>21 MPa, tanδat 0°reached 0.284, tanδat 60℃was below 0.091。...
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