|
With the rapid development of automobile industry , the higher the performance of the tire . According to the literature , nearly 50 percent of the rolling resistance of the tire from the tread rubber of hysteresis loss . The balance of the tire tread wet skid resistance and rolling resistance is the direction of development of high-performance tires . Access the modified group in the polymer chain ends can effectively reduce the number of free end , to improve the bonding force between the polymer with a filler , so as to achieve while reducing hysteresis loss , improve the dispersion capability of the filler in the polymer matrix purposes. Firstly, through the n-butyl lithium and 1,1 - diphenylethylene addition reaction prepared by the modified initiator 1,1 - diphenyl of hexyllithium ( DPHL ) , and the initiator synthesized polybutadiene ene, polyisoprene, polystyrene , as well as linear butadiene - styrene copolymer (SSBR), and finally obtained by SnCl4 coupled double-end modified star polymer. Investigated the polymerization reaction time , the type of end groups , the coupling agent , the coupling reaction temperature , the coupling reaction time and the molecular weight of SSBR coupling efficiency . The results showed that : DPHL activity of the effective anionic polymerization initiator, by its initiator synthetic linear SSBR , when the molecular weight of 70 000 , n (Cl-) / n (Li) is 1.12, and the polymerization reaction time is 60 min , the coupling temperature 60 ℃, the coupling time for more than 30min , the coupling efficiency of up to 74.3%; convert the end of the molecular chain is Bd , the coupling efficiency can be improved ; , the coupling efficiency decreases as the molecular weight increases . The study shows that the mechanical properties of the vulcanizates : compared to by the synthesis of n-butyl lithium star SSBR, the chain end by DPHL Synthesis contains excellent two bulky SSBR physical and mechanical properties of the benzene ring , a stronger interaction with the filler , the Payne effect smallest, highest tanδ of vulcanized rubber at 0 ℃ , the lowest 60 ° C when the tanδ , showing a high wet skid resistance and low rolling resistance , SSBR various performance improvements , more suitable for use in high-performance green energy-saving tire tread with plastic .
|