Polyalkylene glycols with two different end-capping groups of ethylene oxide (EO) and propylene oxide (PO) were used for amination to produce polyetheramine (PEA) on cobalt-based catalysts. Although it is known that the amination of secondary alcohol is more difficult than that of primary alcohol, PO end-capped block copolymers showed remarkably enhanced activity toward PEA and selectivity toward the primary amine compared to EO end-capped block copolymers.