| 摘要 |
<p>A process for producing an epoxidized block copolymer appropriate for modifying agents or modifying aids for rubbery polymers or resinous polymers, adhesives, sealants, etc. The process comprises epoxidizing a block copolymer which may be partly hydrated and comprises a polymer block (A) containing a vinyl aromatic hydrocarbon compound as the main component and another polymer block (B) containing a conjugated diene compound as the main component to thereby synthesize an epoxidized block copolymer (C) and then recovering this polymer from a slurry or solution thereof in an organic solvent by steam stripping in the presence of a surfactant. It is preferably that the surfactant is a nonionic one, in particular, one represented by the general formula: HO(C2H4O)a(C3H6O)b(C2H4)cOH, wherein a, b and c represent each a number of 1 to 1,000, having an average molecular weight of 3,000 to 20,000 and containing 20 to 90 % by weight of polyoxyethylene. According to the process, the epoxidized block copolymer product can be easily recovered from the reaction mixture without giving any prolonged heat history and thus the epoxy group can be prevented from undergoing ring opening. Also, it is possible to obtain an epoxidized block copolymer having such an epoxy equivalent as to give a high elasticity and the characteristics of epoxy compounds.</p> |
