Edge-on lamellae

An alkali halide (NaCl, KCl, KBr, etc.) which has a freshly cleaved (001) face is introduced into a polymer solution and then the pol5nner is to be crystallized epitaxially onto the face of the alkali halide. In general, flexible-chain polymers are apt to be crystallized as rod-like crystals on such an alkali halide these rod-like crystals are edge-on lamellae with their lateral surface being mostly in contact with the (001) face of the alkali halide. A given polymer deposited on an alkali halide can be melted and subsequently crystallized there in an epitaxial fashion. 

Fig. 9 Phase image showing flat-on lamellae surrounded by edge-on lamellae on a BA-C10 film with a thickness of less than 50 nm [64]...

However, in thin films, the growth of the edge-on lamellae is limited by the film thickness (h). The formation of many edge-on lamellae on a thin film cre-... 

Figure 32 shows the continuous AFM deflection images of growing crystals in a (P[(S)-LA]) thin film with a thickness of about 70 nm obtained isother-mally at 165 °C using tapping-mode AFM. After 5 min, some concave areas are detected on the amorphous surface of the thin film (c.f., Fig. 32a). In the concave area, edge-on lamellae emerge and grow with time. Many S-shaped and bow-shaped structures form on the surface after 38 min, as shown in...

Fig. 32 Series of AFM deflection images showing flat-on and edge-on lamellae in P[(S)-LA] thin film with a thickness of 70 nm during isothermal crystallization at 165 °C. The first image (a) was started at 5 min after the temperature was stable at 165 °C. The following images were taken at 10 (b), 17 (c), 24 (d), 31 (e), and 38 min (f), respectively [93]...

Images, such as the one shown in, Fig. 3.21 (left), can be obtained in flat areas of the ePP film. Since intermediate tapping conditions have been chosen (see Chap. 1 and 2 for details), the stiffer phase will appear with a positive phase shift (i.e. bright contrast), while the less stiff phase will appear dark (less positive phase shift). Based on this crude approximation, the elongated bright features seen in, Fig. 3.21 can be attributed to edge-on lamellae, while the dark matrix can be identified as amorphous phase. A quantitative determination of the lamellar thicknesses of these features... 

Figure 9.9 SEM view of transcrystallinity from glass fiber and illustration of (a) edge-on lamellae and (b) flat-on lamellae. (From Ref. 83, with permission.)...

Figure 9.5 Electron micrographs of (a) an etched surface of linear polyethylene showing (A) a group of edge-on lamellae and (B) a basel surface and (C) lamellae side surfaces with striations from pulled-off molecular stems.(b) ESEM of corn oil droplets in a water/oil emulsion.

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