Crystalline transition and morphology variation of polyamide 6/CaCl 2 composite during the decomplexation process

•Decomplexation of PA6/CaCl2 produces porous PA6 with different crystalline forms.•PA6 in γ form is obtained by soaking PA6/CaCl2 in water at room temperature.•Decomplexation of PA6/CaCl2 in boiling water produces PA6 in α form.•If PA6/CaCl2 is soaked in methanol, PA6 microsphere in α crystalline form is formed.•Changing solvents and experimental condition can adjust the morphology of porous PA6.