Isothermal Kinetics of Poly(butylene adipate-co-butylene itaconate) Copolyesters with Ethylenediaminetetraacetic Acid

A series of aliphatic copolyesters, poly(butylene adipate-co-butylene itaconate) (PBABI), have been synthesized using melt polycondensation of adipic acid (AA), itaconic acid (IA), 1,4-butanediol (1,4-BDO), and the tetra-functional group of ethylenediaminetetraacetic acid (EDTA, 0.1 mol %) to form partially cross-linking density as novel thermoplastic unsaturated copolyesters in our previous research. The crystal phase of PBABI copolyesters tended to prefer thermodynamics in the presence of a small amount of EDTA. The isothermal crystallization analysis revealed that the PBABI with EDTA exhibited a higher crystallization rate and a shorter half-time of crystallization than neat PBABI copolyesters. All of the sizes of spherulite/sheet crystals in the BA/BI = 9/1 are smaller than at BA/BI = 10/0 with or without a cross-linking agent, which demonstrated that the morphology behavior tended to form a small sheet crystal in the presence of 10 mol % IA, which played a dominant role in determining the average size of the crystal. These results deepen our understanding of the relationship among the crosslinking agent, the crystal form, and solidification time in PBABI copolyesters, making these kinds of polymers applicable to reinforce three-dimensional (3D) air-permeable polyester-based smart textiles.