Polymers schematic illustration

For the multibranched polymers, an additional mechanism not considered for the linear/star-branched polymers needs to be introduced. For the simplest multibranched polymer, the pom-pom polymer schematically illustrated in Figure 16, McLdsh and Larson combined the equilibrium mechanisms (arm retraction/trunk reptation in the dynamically dilated tube) and the nonequilibrium mechanisms (arm/trunk stretch, CCR, and the arm withdrawal) to formulate a constitutive equation. The arm withdrawal mechanism, leading to partial contraction of the trunk up to a point of tension balance with the arms, is the mechanism not considered for the linear/ star-branched chains. The resulting constitutive equation for the pom-pom chains cannot be cast in a Bemstein-Zapas-Kearsley (BKZ)-type convolution form. This pom-pom con-stimtive equation reproduces the hierarchical relaxation (from... 

Figure 4.1 Schematic illustration of possible changes in the specific volume of a polymer with temperature. See text for a description of the various lettered phenomena.

Table 5.6 Schematic Illustration Showing the Formation of a Linear Polymer by the Reaction of One of the f- 1 Reactive Groups at the End of a Portion of Polymer...

Figure 8.2 Schematic illustrations of AGm versus X2 showing how jUj -may be determined by the tangent drawn at any point, (a) The polymer-solvent system forms a single solution at all compositions, (b) Compositions between the two minima separate into equilibrium phases P and Q.

Figure 9.15 Schematic illustration of size exclusion in a cylindrical pore (a) for spherical particles of radius R and (b) for a flexible chain, showing allowed (solid) and forbidden (broken) conformations of polymer.

Interfacial Polymerization. Many types of polymerization reactions can be made to occur at interfaces or produce polymers that concentrate at interfaces thereby producing microcapsules. Accordingly, this approach to encapsulation has steadily developed into a versatile family of encapsulation processes. Figure 4 schematically illustrates five types of encapsulation processes that utilize these types of reactions. 

In spite of these problems, polymer melts have been sufficiently studied for a number of useful generalisations to be made. However, before discussing these it is necessary to define some terms. This is best accomplished by reference to Figure 8.2, which schematically illustrates two parallel plates of very large area A separated by a distance r with the space in between filled with a liquid. The lower plate is fixed and a shear force F applied to the top plate so that there is a shear stress (t = F/A) which causes the plate to move at a uniform velocity u in a direction parallel to the plane of the plate. 

Figure 15-26. Schematic illustration of a device fabricated lroin a single layer of an interpenetrating donor-acceptor (conjugated polymer/CWi) network.

FIG. 9 Schematic illustration of adsorption of poly(styrenesulfonate) on an oppositely charged surface. For an amphiphile surface in pure water or in simple electrolyte solutions, dissociation of charged groups leads to buildup of a classical double layer, (a) In the initial stage of adsorption, the polymer forms stoichiometric ion pairs and the layer becomes electroneutral, (b) At higher polyion concentrations, a process of restructuring of the adsorbed polymer builds a new double layer by additional binding of the polymer. 

FIG. 2 Schematic illustration of three types of polymer-clay composites. 

Figure 2. Schematic illustrations of (a) polymer-stabilized, (b) surfactant-stabilized, (c) ligand-stabilized metal nanoparticles.

Figure 8.17 Schematic illustration of apparatus used to evaluate the mar resistance of polymer surfaces...

Fig. 8. Schematic illustration of the ER effect in a polymer gel. The paths of the particles have been formed before application of an electric field...

Fig-1 Schematic illustration of the crystallization and melting processes of polymers. The crystallization process corresponds to processes of disentanglement and chain sliding diffusion. The melting process is the reverse of the crystallization process. Between equilibrium melt and ideal crystal, there exists metastable melt and crystal. Cross marks indicate entanglement... 

Figure 1. Schematic illustration of the two critical concentrations in a polymer solution

FIGURE 28-5 Schematic illustration of the movement of cytoskeletal elements in slow axonal transport. Slow axonal transport represents the movement of cytoplasmic constituents including cytoskeletal elements and soluble enzymes of intermediary metabolism at rates of 0.2-2 mm/day which are at least two orders of magnitude slower than those observed in fast axonal transport. As proposed in the structural hypothesis and supported by experimental evidence, cytoskeletal components are believed to be transported down the axon in their polymeric forms, not as individual subunit polypeptides. Cytoskeletal polypeptides are translated on cytoplasmic polysomes and then are assembled into polymers prior to transport down the axon in the anterograde direction. In contrast to fast axonal transport, no constituents of slow transport appear to be transported in the retrograde direction. Although the polypeptide composition of slow axonal transport has been extensively characterized, the motor molecule(s) responsible for the movement of these cytoplasmic constituents has not yet been identified. 

Figure 11. Schematic illustration of (a) a side-by-side and (b) an on-top structure of HC-FC mixed monolayers. Dark squares stand for HC tails of a HC amphi-phile and a HC main chain of a cationic polymer, and open squares stand for FC tails of a FC amphiphile.

Figure 7 Schematic illustration of a self-polishing antifouling paint with soluble CU2O particles exposed to seawater (no insoluble pigments present for simplicity). Notice the pigment-leached layer and the two moving fronts (eroding polymer front, zE, and dissolving pigment front, zP). After Kiil et al. (2002c).

If 7, is positive, component-1 is selectively adsorbed on the polymer and if polymer is added to the system, the concentration of component-1 must also be increased, if the activity of component-1 is to remain constant. A helpful schematic illustration has been provided by Kratochvfl13I) and is shown in Fig. 39. The example relates to a binary solvent composition of 1 1 for the bulk solvent 1 — solvent 3 mixture. 

Fig. 9.16 Schematic illustration of drying process for SWNT-filled polymer emulsion. Initially the nanotubes and polymer particles are uniformly suspended in water (left). Once most of water has evaporated, the polymer particles assume a close-packed configuration with the nanotubes occupying interstitial space(center). Finally, the polymer particles will interdiffuse (i.e., coalesce) to forma coherent film, locking the SWNTs within a segregated network (right) (Keren et al, 2003. With permission from Wiley-VCH)...

Figure 3 Schematic illustration of a hybrid hydrogel system—genetically engineered coiled-coil protein domains used to crosslink synthetic water-soluble polymers. Divalent transition metal ions are shown to form complexes with nitrogen-oxygen-donor ligands on the synthetic polymer side chains and the terminal histidine residues in the coiled coils.

Fig. 9.1 A schematic illustration of surface coatings with their typical thickness ranging from angstroms to micrometers. Selected are monomolecular layers fabricated by the transfer of Langmuir-Blodgett (LB) films onto solid substrates (1) self-assembled monolayers (SAMs) (2) multilayers thereof (3) polymer-...

Fig. 9.35 Schematic illustration of the self-condensing vinyl polymerization ATRSIP on planar silica substrates resulting in hyper-branched surface-bonded polymer layers.

Fig.1 Schematic illustrating the formation of surface-anchored polymer assemblies by utilizing the grafting onto and grafting from methods...

Fig. 3 Schematic illustrating a conformations of stuface-anchored polymers, and polymer brush assemblies with a b grafting density gradient, and c a gradient in polymer length. Part d depicts polymer conformations on a substrate comprising grafting density and polymer length orthogonal gradients...

The fracture behavior of toughened polymers, containing rubber or inorganic fillers, may involve several mechanisms, as schematically illustrated in Fig. 8.1 (Garg and Mai, 1988a). These include ... 

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