Lamellar morphology period

Fig.23. Schematic illustration of wetting geometries expected for ultra-thin films of diblock copolymers a - parallel lamellae, b - surface (pinned) micelles, c - perpendicular lamellae. L corresponds to the equilibrium period of the lamellar morphology...

Figure Bl.9.13. Time-resolved SAXS profiles during isothermal crystallization (230 °C) of PET (the first 48 scans were collected with 5 seconds scan time, the last 52 scans were collected with 30 seconds scan time) calculated correlation functions y(r) (normalized by the invariant Q) and lamellar morphological variables extracted from the correlation functions (invariant Q, long period crystal lamellar thickness and...

The periodic systems that are subjected to small-angle scattering studies are mostly of lamellar morphology, as in folded-chain lamellar crystals, membrane structures, and block copolymers with lamellar ordering. We will therefore confine our discussion to lamellar systems only and discuss them in more detail in the rest of this section. 

C. Dark-field electron microscopy reveals its morphology crystallites are lamellar in shape, around 15 mm thick (along the chain) and 100 nm long (in the lateral direction). The lamellae also have somewhat irregular boundaries. Hudson et al. [110] optimized the etchant composition to reveal clearly the periodic lamellar morphology. 

The long period, spacing between adjacent crystalline lamellae layers, can be estimated from a circular averaged 1-D SAXS data. The lamellar morphology of iPP in the blends was also determined from the position of the SAXS maxima. 

Lamellar Morphology. Formation of lamellar surfactant-induced structures was studied by Brinke et al. [33] using scaling arguments. This structure consists of polymer layers of thickness D and an interlayer space filled with surfactant tails of thickness 2L. The long period of the structure is Lp = D + 2L. The interface area A is considered in calculations. The free energy of such a layered system consists of three contributions ... 

Many types of polymers self-organize into lamellar (sheet-like) morphologies. This includes, among others, semicrystalline polymers, symmetric linear AB diblock copolymers, and smectic main-chain liquid crystalline polymers. The characteristic cf the lamellar morphology is that there is a variation of the electron density in the direction normal to the lamellae. The spatial period of the variation can be large, of the order lO-lOOnm, so the scattering occurs principally at small scattering vectors. 

DlMarzio et al. [78] and Whitmore and Noolandi [79] theoretically predicted an equihbrium lamellar morphology formed in crystalline-amorphous diblock copolymers. The long period of the lamellar morphology L, that is, a sum of crystalline layer thickness and amorphous layer thickness, is expressed by a scaling form ... 

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