Star-shaped isoprene-styrene copolymer and preparation method thereof

Abstract

The invention provides a star-shaped isoprene-styrene copolymer containing a random transition section and a preparation method thereof. The star-shaped isoprene-styrene copolymer is characterized in that the structural formula is [I1-S1-I2 / S2]n-Y,], wherein Y is Si or Sn, n is a branching degree, n is more than or equal to 2.5 and less than or equal to 4, and I1-S1 is a transition section copolymer of polystyrene and polyisoprene; I2 / S2 is a random section copolymer of the polystyrene and the polyisoprene, the mass fractions of transition sections of the polystyrene and the polyisoprene are 40-75wt%, and the mass fractions of random sections of the polystyrene and the polyisoprene are 25-60wt%. High styrene rubber disclosed by the invention has the characteristics of high hardness and good intensity and elasticity; when the high styrene rubber is used simultaneously with multiple synthetic rubber or natural rubber, the properties of rigidity, hardness, wearing resistance, tear resistance, dielectricity and the like of rubber products can be improved, and the high styrene rubber can be widely applied to the rubber processing fields of tires, tapes, rubber tubes, rubber overshoes and the like and other industries and can be further used for modifying synthetic plastics.

Description

technical field [0001] The present invention relates to a kind of isoprene-styrene star-shaped copolymer containing random gradient segment and its preparation method. The synthesized polymer is characterized by high hardness, high wear resistance and good elasticity of star-shaped high-styrene rubber . Background technique [0002] For a copolymer composed of isoprene and styrene, the bound styrene is generally 23-30%. If the bound styrene content is high, the resulting copolymer will have greater plasticity; otherwise, the copolymer will have greater elasticity. Generally, copolymers with a styrene binding amount of 45% to 70% in the molecular structure are called high-styrene rubbers, and those with a combined styrene content of more than 70% are called high-styrene resins. Due to the high amount of bound styrene in high styrene rubber, its physical properties are different from those of general-purpose styrene-butadiene rubber. High styrene rubber is rarely used alone....

AI Technical Summary

Problems solved by technology

And mostly adopt latex coagulation technology in the prior art, although this technological process can obtain the high styrene rubber with better performance, the main problem that this method exists is: at first in technology, need to synthesize SBR-1500 or SBR-1500 respectively earlier SBR-1502 latex and high styrene resin emulsion, the two emulsions that pass the analysis are mixed in a certain proportion, and then coagulated and dried to obtain high styrene rubber. The process is relatively long and requires two water phases, oil phases, Initiator preparation and degassing and other synthetic procedures; secondly, in terms of production cost, since the conversion rate of synthetic SBR-1500 or SBR-1502 latex monomer is only 70%, unreacted monomer accounts for 30%, and this part of monomer is in small and medium-sized It is difficult to recycle in large-scale production devices, resulting in high production costs and relatively large equipment, auxiliary materials, personnel, time, and energy required for the polymerization process; in addition, in the production cycle, since the synthesis temperature of high styrene resin emulsion is High-temperature polymerization, there are many structural gels in the polymerization kettle, and the polymerization kettle used usually needs to be cleaned once to produce 10 batches, so the utilization rate of the equipment is low

The above-mentioned polymers all have the disadvantages that the tensile strength and hardness of the product are not high enough

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