Dual Effects of Interfacial Interaction and Geometric Constraints on Structural Formation of Poly(butylene terephthalate) Nanorods

Thin-Film Crystallization of Poly(butylene terephthalate) from the Anisotropic Amorphous State

“…To this end, we investigate the thin-film crystallization of PBT from the amorphous state. Usually, polymer thin films with a thickness of less than ∼1 μm can impose a significantly one-dimensional (1D) confinement effect. − Polymer crystallization of thin films on solid substrates, including commercial engineering plastics, such as PET and PA 6, has demonstrated that the chain orientation, segmental mobility, transporting process, and surface free energy at the interface can be influenced greatly by the 1D confinement. − The lamellae with preferential orientations, either flat-on or edge-on, grown in polymer thin films indicate that the crystallization pathway or kinetics are different from that in bulk crystallization. ,,, It is also reported that some preordered structure, which is hardly detected or even absent in the bulk state, can be trapped in the 1D confined space. , For PBT thin films, we hypothesize that the 1D confinement effect may retain the mesophase once it has developed and/or slow down the transition from the metastable state to the crystal phase.…”