Poly micrographs

Figure C2.11.2. A scanning electron micrograph showing individual particles in a poly crystalline alumina powder.

Figure 3 TEM micrograph of a deformed thin film of an 8.2 mol% poly(styrene-co-sodium methacrylate) ionomer cast from THE.

We have studied the effect of monomer concentration in the dispersion polymerization of styrene carried out in alcohol-water mixtures as the dispersion media. We used AIBN and poly(acrylic acid) as the initiator and the stabilizer, respectively, and we tried isopropanol, 1-butanol, and 2-butanol as the alcohols [89]. The largest average particle size values were obtained with the highest monomer-dispersion medium volumetric ratios in 1-butanol-water medium having the alcohol-water volumetric ratio of 90 10. The SEM micrographs of these particles are given in Fig. 15. As seen here, a certain size distribution by the formation of small particles, possibly with a secondary nucleation, was observed in the poly-... 

Figure 20 A typical scanning electron micrograph of the macroporous uniform poly(styrene-divinylbenzene) late> particles. Magnification 1200 x, (particle size = 16.0/rm average pore diameter = 200 nm).

Figure 16 Scanning electron micrograph of poly(cardanyl acrylate) beads.

The next two examples illustrate more complex surface reaction chemistry that brings about the covalent immobilization of bioactive species such as enzymes and catecholamines. Poly [bis (phenoxy)-phosphazene] (compound 1 ) can be used to coat particles of porous alumina with a high-surface-area film of the polymer (23). A scanning electron micrograph of the surface of a coated particle is shown in Fig. 3. The polymer surface is then nitrated and the arylnitro groups reduced to arylamino units. These then provided reactive sites for the immobilization of enzymes, as shown in Scheme III. 

FIGURE 3 Scanning electron micrograph (1200x magnification) of the surface of a porous alumina particle coated with poly(diphenoxy-phosphazene). Surface nitration, reduction, and glutaric dialdehyde coupling immobilized enzyme molecules to the surface. (From Ref. 23.)... 

Figure 2. Representative optical micrographs of poly-HEMA cross-linked with EDMA. (a) and (b) represent the gel-type polymer produced by suspension co-polymerization in the dry and swollen state, respectively, (c) and (d) represent the macroreticular polymer produced by suspension co-polymerization in the presence of a porogen (toluene), in the dry and swollen (vide infra) state, respeetively [13], (Reprinted from Ref [15], 1996, with permission from Elsevier.)...

Recent developments have allowed atomic force microscopic (AFM) studies to follow the course of spherulite development and the internal lamellar structures as the spherulite evolves [206-209]. The major steps in spherulite formation were followed by AFM for poly(bisphenol) A octane ether [210,211] and more recently, as seen in the example of Figure 12 for a propylene 1-hexene copolymer [212] with 20 mol% comonomer. Accommodation of significant content of 1-hexene in the lattice allows formation and propagation of sheaf-like lamellar structure in this copolymer. The onset of sheave formation is clearly discerned in the micrographs of Figure 12 after crystallization for 10 h. Branching and development of the sheave are shown at later times. The direct observation of sheave and spherulitic formation by AFM supports the major features that have been deduced from transmission electron and optical microscopy. The fibrous internal spherulite structure could be directly observed by AFM. 

Fig. 3 a TEM micrograph of polystyrene-fc-poly-(L-lactide), PS-fc-PLLA, neat (d>plla = 0.35). b Schematic representation of nanohelical morphology. From [16]. Copyright 2004 American Chemical Society... 

Fig. 1.2 Scanning electron micrographs of (A) the silica wall of the diatom Stephcmopyxis turns (reproduced from [21] by permission ofWiley-VCH) and (B-D) singular morphologies of silica synthesized using poly-L-lysine and pre-hydro-lyzed tetramethyl orthosilicate (TMOS) under...

Fig. 1.5 SEM micrographs of (A) donut-shaped poly(aspartate) and MgCl2 by alternate spin CaC03 crystals grown on polyacrylic acid grafted coating and crystallization. (A) and (B) adapted chitosan, (B) CaC03 hollow helix, fractured by from [84] and [85]with permission from Elsevier, micro-manipulation, formed on poly(a-L-aspar- and (C) from [88] (reproduced by permission of tate),and (C) double layered aragonitethin films The Royal Society of Chemistry), grown on a chitosan matrix in the presence of...

Fig. 5.3 SEM micrographs of Ti02 nanoparticles obtained in the presence of pR5 (scale bar= 1.2 pm) (a) and poly-L-Lysine (scale bar=750nm). (b) (Reprinted with permission from [36], Copyright (2006) American Chemical Society).

Figure 15.14 Study of the sample from the Dogon statuette 71.1935.105.169. (a) Optical microphotograph (b) SEM micrograph showing the layer structure ToF SIMS images of (c) proteins, (d) polysaccharides and (e) stearic acid (f) superposition of the distribution of poly saccharides and stearic acid (see colour Plate 9)...

Figure 12. Scanning electron micrograph of negative images delineated in poly(TBMA-co-ST) resist at 7.6 mJ/cm2 of 254 nm radiation.

Figure 9. Electromicrograph of a high density poly- Figure 10. Light micrograph of polyethylene fibrids.

Fig. 10. Scanning electron micrographs of monolithic poly(divinylbenzene) capillary column. Note that the porous monolith is surrounded by an impervious tubular outer polymer layer resulting from copolymerization of the monomer with the acryloyl moieties bound to the capillary wall. This layer minimizes any direct contact of the analytes with the surface of the fused-silica capillary...

Figure 5. Transmission electron micrograph of poly[(CO,SA,TDI)-SIN-(S,DVB)], 10/90, after being fully polymerized and postcured. Oil phase is stained dark.

Introns in DNA can be visualized in an electron micrograph of DNA-mRNA hybrids (Figure 1-3-8). When mRNA hybridizes (base pairs) to the template strand of DNA, the introns appear as unhybridized loops in the DNA. The poly-A tail on the mRNA is also unhybridized, because it results from a posttranscriptional modification and is not encoded in the DNA. 

Figure 4 Electron micrographs of unchlorinated poly(vinyl acetate-co-oxazolidinone) (top) and chlorinated poly(vinyl acetate-co-oxazolidinone) (bottom) coated medical catheters exposed for 72 h to a flowing aqueous suspension of Pseudomonas aeruginosa (10 CFU/mL). 

Fig. 9.33 SPM micrograph of gold nanoparticles decorated with grafted chains of poly(n-...

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