Morphology orientation

Block copolymer Structure Morphology Orientation method Ref. 

Details are given of the interaction between the macrostructure and morphology of PP structural foam mouldings made by the gas-counter pressure process. The morphology, orientation, and processes ofnon-isothermal... 

Counter stain with methylene blue for morphological orientation. 

Poly(ethylene terephthalate) (PET) which is manufactured by a stagewise melt polymerization process consisting of transesterification, prepolymerization and finishing polymerization steps, is one of the fastest growing thermoplastic polyesters used extensively for fibers, films, bottles, injection molded parts and other products [1], Considerable scientific effort has been made to elucidate its properties. Important aspects can be studied using solid-state NMR spectroscopy to determine morphology, orientation and mobility in the bulk material. 

As well as influencing chromophore types and levels, variations in production conditions result in fibers of varying morphology (orientation, crystallinity, and supramolecular order) (3). Because morphology itself may markedly effect photooxidative sensitivity, the extent of this effect was explored by first studying the susceptibility of the various filaments to y-initiated oxidation. The y-initiation is believed to be completely random and it is not dependent on trace quantities of chromo-phores or the build-up of oxidation products, in contrast to photooxidation, yet it is followed by the same propagation and termination steps as photo-initiated oxidations (2,4). 

Fig. 5.12 Schematic of the surface-ordering process in a diblock copolymer. The top diagram shows the dibiock copolymer in a phase mixed state. This is not accessible for PS/PMMA co-polymers via solvent-casting processes. The center diagram corresponds to a microphase-separated morphology where the periodic lamellar microdomains are randomly oriented in the specimen. After annealing for 24 h at 170 °C, the copolymer exhibits a lamellae morphology oriented parallel to the surface as shown in the bottom picture. Reprinted with permission from ref. [96]...

In summary, in the next few decades we will have to move from process thermodynamics to a more material morphology-oriented approach including the possibilities of biotechnology to materials production. 

SCORIM results in substantial enhancement of the physical properties of iPR The enhanced properties are related to the formation of shish-kebab morphology, and hence the high levels of molecular orientation that result from the application of macroscopic shears to a solidifying melt in a mold cavity. In this chapter, SCORIM technology is first described, and then relationships between processing conditions and mechanical properties are discussed, including a discussion on shish-kebab morphology, orientation and the occurrence of 7 phase in processed iPP. 

Keywords homopolymer, block copolymer, hinge, living hinge, plastic hinge, hinge geometry, process parameter, morphology, oriented layers, stacked lamellae, molecular orientation, hard elasticity, deformation mechanism, transmission electron microscopy (TEM). 

Keywords crystallite draw ratio, long period, mechanical properties, membrane, three-dimensional morphology, orientation factor, roU-trusion, SAXS, tie molecules, WAXS. 

Final properties of an injection-molded product, made of semi-crystalline polymers, strongly depend on the flow-induced microstructure (crystallinity, morphology, orientation, etc.). Particularly, the enhancement in polymer crystallization rate crucially changes the soUdiiication behavior, and the oriented microstructure leads to a local anisotropy in thermal and mechanical properties. 

Cross-links Highly ordered structures Crystallinity Crystalline thickness Spherulitic size and morphology Orientation Hybridization (blends and composites) Material Morphology Material shape and dimensions Porosity and pore size Surface Treatment Coating Alkaline treatment Stress or strain... 

Liquid crystalline polymers have been discussed in many texts and review papers [65, 400-413] during the last decade, in which the synthesis, processing, morphology, orientation and structure-property relations are described. The major applications of these materials have been as high modulus fibers and films, with unique properties due to the formation of ordered lyotropic solutions or thermotropic melts which transform easily into highly oriented, extended chain structures in the solid state. 

The oxygen diffusion constant, D, depends on the state of aging process, the reactant concentrations, and the sample morphology (orientation, crystallinity). It follows approximately an Arrhenius-type temperature dependence as in Eq. (66), where Do is a proportionahty constant, and R the molar gas constant. 

Herrmann, W., Uhl, C., Heinrich, G., and Jehnichen, D. (2006) Analysis of HNBR-montmorillonite nanocomposites morphology, orientation and macroscopic properties. Polymer Bulletin, 57, 395-405. 

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