Electron microscopy blends

In order to see the effect of the compatibilizer more clearly, SEM (scanning electron microscopy) micrographs of the peeled back exposed surface of the spun fibers are shown in Fig. 7. In a noncompatibilized blend, the long TLCP fibrils are bundled together (Fig. 7A). The fibril surface looks quite clean and smooth along the... 

Characterization and control of interfaces in the incompatible polymer blends were reported by Fayt et al. [23]. They used techniques such as electron microscopy, thermal transition analysis, and nonradiative energy transfer (NRET), etc. They have illustrated the exciting potentialities offered by diblock copolymers in high-performance polymer blends. 

Electron and optical microscopes are being used to see blend homogeneity. Elastomer-plastic blends are somewhat easier to identify than elastomer-elastomer blends because normal staining techniques, e.g., osmium tet-raoxide, can be used in the case of plastic-elastomer blends. Normally, there are two methods that are followed for examining the blend surface by electron microscopy. 

Reactive compatibilization of engineering thermoplastic PET with PP through functionalization has been reported by Xanthos et al. [57]. Acrylic acid modified PP was used for compatibilization. Additives such as magnesium acetate and p-toluene sulfonic acid were evaluated as the catalyst for the potential interchange or esterification reaction that could occur in the melt. The blend characterization through scanning electron microscopy, IR spectroscopy, differential scanning calorimetry, and... 

In the matrix of PLA/ polycaprilactone (PCL)/OMMT nano-composites, the silicate layers of the organoclay were intercalated and randomly distributed (Zhenyang et at, 2007). The PLA/PCL blend significantly improved the tensile and other mechanical properties by addition of OMMT. Thermal stability of PLA/PCL blends was also explicitly improved when the OMMT content is less than 5%wt. Preparation of PLA/thermoplastic starch/MMT nano-composites have been investigated and the products have been characterized using X-Ray diffraction, transmission electron microscopy and tensile measurements. The results show improvement in the tensile and modulus, and reduction in fracture toughness (Arroyo et ah, 2010). 

The mechanism of formation of morphology structures in iPP-E-plastomers blends via shear-dependent mixing and demixing was investigated by optical microscopy and electron microscopy. A single-phase stmcture is formed under high shear condition in injection machine after injection, namely under zero-shear environments, spinodal decomposition proceeds and leads to the formation of a bicontinuous phase stmcture. The velocity of spinodal decomposition and the phase separation depend on the molecular stmcture of iPP and E-plastomer components. 

Electron microscopy, 16 464, 487-495 history of, 16 487-488 in polymer blend morphology determination, 20 339-340 of PVC particles, 25 658-659 of silica, 22 371-372 in surface and interface imaging, 24 75-80... 

The melt mixed 80/20 PS/iPP blend displays a set of exotherms, where the amount of the iPP component that was heterogeneously nucleated is substantially reduced as indicated by the decrease of the crystallization enthalpy in the temperature region where the iPP crystallizes in bulk, i.e., at 109-111 °C (exotherm labeled A). This effect is due to the confinement of iPP into a large number of droplets. If the number of droplets of iPP as a dispersed phase is greater than the number of heterogeneities present in the system, fractionated crystallization occurs. The number of droplets for this composition is known (by scanning electron microscopy observations) to be of the order of 1011 particles cm-3 and polarized optical microscopy (POM) experiments have shown that this iPP contains approximately 9 x 106 heterogeneities cm-3. In fact, it can be seen in Fig. 1 that the fractionated crystallization of the iPP compon-... 

Prerequisite for these observations was the development of proper analytical procedures to visualize the morphology of these blends by electron microscopy.5 7... 

The essential step is the efficient grinding and blending of raw materials. The final properties of cement strongly depend on its mineral composition so that raw composition and firing conditions are adjusted, depending on the type of cement to be produced. The microstructure of the steel fiber-cement paste interface was studied by scanning electron microscopy (SEM). The interfacial zone surrounding the fiber was found to be substantially different from the bulk paste further away from the fiber surface. The interfacial zone consisted of... 

Electron microscopy has been performed using a sample synthesised at w = 10, [Cd2+]/[S2 ] = 2, and characterized by 430-nm absorption onset, which corresponds to a CdS diameter equal to 25 A. The microanalysis study shows the characteristic lines of sulfide and cadmium ions, indicating that the observed particles are CdS semiconductor crystallites. The electron diffractogram shows concentric circles, which are compared to a simulated diffractogram of bulk CdS. A good agreement between the two spectra is obtained, indicating the particles keep zinc-blend crystalline structure (fee) with a lattice constant equal to 5.83 A. 

The micrographs obtained from scanning electron microscopy are shown in Fig. 54 for the tensile fractured surface of 50 CR/50 XNBR self-crosslinked blend filled with 10 phr layered silicate (Fig. 54a) and for the same blend without any... 

Transmission electron microscopy measurements reveal that the nanotubes are selectively located in the PA-6 phase. The selectively filled PA-6/ABS blends show a highly irregular, cocontinuous morphology. 

Thin epitaxial films (less than 3 nm) of CrAs and CrSb with zinc-blende structure can be grown on GaAs substrates by MBE. Their 7c exceeds 400 K (Akinaga et al. 2000c Zhao et al. 2001b). A zinc-blende structure is confirmed by in-situ RHEED collected during the growth and ex-situ cross-sectional transmission electron microscopy (TEM). The... 

The morphology of blends of asymmetric PS-Pl diblocks that do not form lamellar phases has been investigated using transmission electron microscopy by Koizumi et al. (1994c). They considered three cases (i) approximately equal... 

Microscopy. This is a powerful tool for studying visually the distribution of the two phases in the polyblend. One can tell not only the domain size of the dispersed phase but also which polymer forms the dispersed phase from refractive index. A phase contrast light microscope can detect heterogeneity at the 0.2-10 /x level. If the sample can be stained preferentially and sectioned with microtome, then under favorable conditions electron microscopy can show heterogeneity to a very fine scale. In a study of PVC-poly(butadiene-co-acrylonitrile) blend,... 

Tihe technological properties and the commercial application of several polymer blends have been studied extensively. Investigations of the basic principles, however, relating the phase structure of the blends to the properties of the individual components have not been carried out to an extent justified by the industrial value of these materials. Several methods have been used, the most successful being optical and electron microscopy and dynamic-mechanical measurements. Critical factors and difficulties in the morphological studies of polymer blends have been... 

Changing the milling temperature has a pronounced effect on the mechanical properties (19) and the physical state of the polymer blend (Table I). Figure 6 shows that the permeability and diffusion coefficients decrease considerably on increasing the milling temperature. This decrease can be correlated with the increased amount of very small PVC particles (< 0.2 /on) as observed by electron microscopy. The effect is... 

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