The Synthesis And Application Of Morpholine Modifiers In Solution Styrene And Butadiene Rubber

The solution styrene and butadiene rubber(SSBR) is commonly produced by organolithium initiators in the presence of polar modifiers. One of the key technology is the selection of the modifiers which can control the microstructure of the polymer and increase the rate of polymerization, and it has a direct effect on the properties of SSBR.In this thesis, the anionic copolymerization of butadiene and styrene is conducted with n-butyllithium(n-BuLi), cyclohexane and hexane mixing solution, and the self-made asymmetric ethers-morpholine modifiers. The modifiers are synthesized using the Dazens method including ethoxyethyl morpholine (EOEM), propoxyethyl morpholine (POEM), butoxyethyl morpholine (BOEM) and hexoxyethyl morpholine (HOEM).The kinetic behaviors of the copolymerization, the relationship between polymer composition and conversion at different modifier contents are studied. The kineties research indicates that the polymerization speed increases with the adding of the modifiers, so the styrene monomer is randomized along the polymer chain to form random SSBR, and the rate regulation ability decreases as the following order: EOEM>POEM>BOEM>HOEM.The microstructure research shows that the regulation ability of the modifiers are strong, and the randomizers regulation ability decreased in following order: EOEM>POEM≈BOEM≈HOEM; The research shows that the adding of the modifiers has little influence on the molecular weight and its distribution. It is found that coupling efficiency decreased slightly with increasing modifier contents.Furthermore, the results of the physical properties show that the resulting products have both high wet skidding-resistance and low rolling-resistance properties, which are valuable for using in making automobile tire treads.