On the basis of analyzing the structure characteristics of TAS - 2a, BAB-type block copolymer is put forward, with its structure being anchored group in the centre.

在分析TAS - 2a结构特征的基础上，指出其结构为锚固基团处于中央的BAB型嵌段共聚物。

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The second working group or Track was subdivided into Track 2A and 2B.

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