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Preparation of PIM(X)-b-PEO(Y) multiblock copolymers in two reaction steps. Step 1: polycondensation with excess of 2 over 1 to achieve low molecular PIM-1 (1.1:1 = 8–10 kg/mol, and 1.025:1 = 20–30 kg/mol); and Step 2: polycondensation with DHBA-di-esters 5a–c.
