| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a vinyl aromatic polymer, reinforced with rubbers and having rubber phases in a bimodal form. SOLUTION: This method for obtaining a vinyl aromatic polymer reinforced with rubbers comprises respectively separately and continuously feeding solutions of each rubber dissolved in a liquid medium substantially composed of at least one vinyl aromatic monomer to two kinds of reactors, continuously polymerizing the monomer until 10-50% of the whole monomer is respectively converted, producing the first composition containing the first prepolymer containing a rubber phase having 0.04-1.8μm volume-average diameter of the grafted rubber particles as a base in the one reactor, producing the second composition containing the second prepolymer containing a rubber phase having 0.6-12μm volume-average diameter of the grafted rubber particles as a base in the other reactor, then mutually continuously mixing both the compositions, further polymerizing the resultant composition and then separating the prepared polymer from the unreacted monomers. The resultant vinyl aromatic polymer has the rubber phases of a bimodal form. |
