Several Kinds Of Modification Of Styrene-Butadiene Rubber By Coupling

The thesis synthesized three kinds of modified polybutadiene-styrene copolymers:star-polyisoprene-polybutadiene-styrene copolymer (S-PI-PSB), star-polystyrene-butadiene copolymer(S-PSB) and SiO2 modified polystyrene-butadiene(PSB-SiO2), through anionic polymeri-zation by divinylbenzene(DVB), SiCl4, silica as coupling agents. The thesis researched the factors that influenced the coupling reactions, such as the coupling agent type and dosage, the way of the reagents adding, the temperature of the coupling reaction, the regulator type and dosage and so on. The thesis also characterized the performance of modified styrene-butadiene rubber.Basing on the laboratory research in the 2L reactor, the thesis did the research on the amplifying reaction of star-polyisoprene-polysyrene butadiene copolymer(S-PI-PSB) polymerization in the 15L reactor, the thesis focused on the factors that influenced coupling reaction and the rules of the coupling reaction. The results showed that the coupling efficiency could be significantly improved through the coupling agent DVB dropped, the time of coupling reaction extended, the temperature of the coupling reaction increased. The coupling efficiency could reases 83.1%, by dropping DVB 0.5h at 50℃, then increasing the temperature to 70℃and reacting 1h. The craft is proved stability and the coupling efficiency is high.In order to solute the question that the coupling efficiency is relatively low with the high 1,2-butadiene content(Bv%), the thesis researched the influence with using the regulators:tetrahydrofurfuryl alcohol ethyl ether(TFEE)/sodium dodecyl benzene sulfonate(SDBS), N,N-dimethyl-tetrahydro-furfurl amine, such as the regulators dosage, the kinds of the coupling agents, the content of the 1,2-butadiene. The results showed that the coupling efficiency of the dual regulation system was lower than the N,N-dimethyl-tetrahydro-furfurl amine regulation system and the coupling efficiency reduced with the 1,2-butadiene content increasing. The star-polystyrene-butadiene copolymer with 60% content of 1,2-butadiene could be synthesized by using the regulator N,N-dimethy-tetrahydro-furfurl amine and the coupling agent DVB.The hybrid material PSB-SiO2 was synthesized through the coupling reaction between the silica with lots of hydroxyl groups on the surface and the chlorosilane-end polystyrene-butadiene copolymer. The results showed that the new blending method could improve the mechanical properties of rubber and the dispersion of silica. The tensile strength of the hybrid material is 19.8MPa, and the tear strength is 53.9MPa, as well as the silica partical size could be 20-100nm.