A TEM study on melt-crystallized poly (butylene terephthalate)

Abstract

A study was made to investigate an optimum condition for ruthenium tetraoxide staining of poly(butylene terephthalate) (PBT) with glass transition temperature as low as ca. 23 degrees C for TEM observation of melt-grown PBT crystals. The morphological study of ultrathin sections prepared based on optimum staining at 25 degrees C for 8 h revealed formation of fringed-micellar crystal nuclei in the early stage and folded-chain fringed-micellar crystals in the later stage of isothermal crystallization at 40 degrees C from melt. The fraction of chain-folded crystals increased with increasing crystallization temperature from the quantitative analysis of crystal thickness in comparison with the reported morphology using the replica method.

Density of heterogeneous and homogeneous crystal nuclei in poly (butylene terephthalate)

“…5). Crystallization at high temperature, in contrast, leads to growth of laterally extended lamellae of rather low thickness, as was reported also elsewhere [47]. The AFM image of the sample crystallized at 180°C shows edge-on seen lamellae with an approximate thickness of 6-8 nm.…”

Crystallization of Poly(butylene terephthalate) from the Glass

“…Therefore, the observed SAXS peak is related to a nanoscale correlation among the corresponding entities and the entities are crystalline. The ensemble of nanoscale entities is regarded as a nodule structure similar to the one which is observed in iPP quenched from the melt to 0 °C. − Manabe and co-workers have studied the morphology of PBT isothermally crystallized at 40 °C from melt by transmission electron microscopy . They have observed granule-like crystalline domains with indistinct boundary in the PBT sample.…”

Facile construction of cellulose nanocomposite aerogel containing TiO2 nanoparticles with high content and small size and their applications

“…A copper grid coated with a holey carbon support film was used to prepare samples for TEM observation. A small piece of the central part of the aerogel specimen was embedded in acetone and then to a 7:3 (v/v) mixture of methylmethacrylate and butylmehtacrylate monomers containing 1.4% (w/v) benzoyl peroxide as initiator at 25°C for 6 h. Then ultrathin sections were prepared in an ultramicrotome equipped with a cryosectioning unit and the section approximately 100 nm thick was mounted on a grid with carbon support (Manabe et al 2002). Atomic force microscopy (AFM) analysis of the composite aerogel was carried out on an SPM-9500J3 AFM instrument (SHIMADZU, Japan).…”