Polymer assemblies

In this chapter we have focused attention on various aspects of individual polymer molecules. In the next three chapters we shall examine some properties of assemblies of polymer molecules. Our interest in these chapters will be mostly directed toward samples of pure polymer assemblies of high and low molecular weight molecules-polymer solutions—will be discussed in Part III of this book. 

The elastomer produced in greatest amount is styrene-butadiene rubber (SBR). Annually, just under 10 lb of SBR is produced in the United States, and almost all of it is used in automobile tires. As its name suggests, SBR is prepared from styrene and 1,3-buta-diene. It is an example of a copolymer, a polymer assembled from two or more different monomers. Free-radical polymerization of a mixture of styrene and 1,3-butadiene gives SBR. 

Mayo-I.ewis equation, in enpolymcri/alion 338 M C see methyl erotonate mechanically assisted polymer assembly (MAPA) 562... 

Maruyama, N., Koito, T, Sawadaishi, T, Karthaus, O., Ijiro, K., Nishi, N., Tokura, S., Nishimura, S. and Shimomura, M. (1998) Mesoscopic pattern formation of nanostructured polymer assemblies. Supramol. Sci., 5, 331-336. 

Fig. 30. A trivial open polymer assembled from pyridine-functionalized porphyrins.

Fig. 34. A cooperative open polymer assembled from imidazole-functionalized porphyrins.

Fig. 2. Schematic representation of the supramolecular cylinders of the dendrimer derived from macromonomer 9 (R=OC12H25,n=3) in the Qh mesophase atop view of a cylinder containing six repeat units in a stratum with the alkyl tails melted to match the average column radius determined by X-ray scattering experiments b side view of a cylinder containing 30 repeat units of the polymer assembled with melted alkyl tails. Reproduced with permission from references 5 a...

In 1997, Decher reported a fundamental concept regarding the multilayer nanoassemblies composed of polycations and polyanions [24]. The polymer assemblies were prepared by an alternate adsorption process, as shown in Figure 6.5. If a substrate has an anionic charge on its surface then polycation could adsorb onto the surface as a first layer. Polyanion could subsequently adsorb onto the surface by immersing in a... 

Figure 6.4 The preparation of nanostructured materials in solution evolves from (a) the classic examples of suspension, dispersion, or emulsion polymerization, to the methods that include the covalent crosslinking of select domains within supramolecular polymer assemblies (b) core crosslinking of polymer micelles (c) shell crosslinking of polymer micelles (SCKs) (d) nanocages from core-eroded SCKs (e) shaved hollow nanospheres from outer shell/core-eroded vesicles.

McQuade DT, Kim J, Swager TM (2000) Two-dimensional conjugated polymer assemblies interchain spacing for control of photophysics. J Am Chem Soc 122 5885-5886... 

After elongation has proceeded for a sufficient period of time, the protomer and polymer will reach concentrations corresponding to the equilibrium constant Ko, which from our earlier discussion may be represented as k-/k+. This constant represents the critical concentration for polymer assembly, and protomer concentrations which fall below the magnitude of this constant will not spontaneously assemble. In this sec-... 

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

The cytoplasm of eukaryotic cells is traversed by three-dimensional scaffolding structures consisting of filaments (long protein fibers), which together form the cytoskeleton. These filaments are divided into three groups, based on their diameters microfilaments (6-8 nm), intermediate filaments (ca. 10 nm), and microtubules (ca. 25 nm). All of these filaments are polymers assembled from protein components. 

Wilson AJ. Non-covalent polymer assembly using arrays of hydrogen-bonds. Soft Mater 2007 3 409-425. 

Figure 6.13 (a) Recognition-mediated nanoparticle-polymer assembly through three-point... 

Synthesis of polymeric capsules involves polymer self-assembly on many levels and length scales. Approaches to their synthesis include cases where monomers are polymerized around a liquid template, premade polymers are assembled around liquid and solid templates, premade particles are assembled around templates, and small molecules or polymers assemble spontaneously. Each method offers unique challenges and advantages, and each allows the production of capsules with different properties. 

Photoinduced Charge Separation and Electron Relay in Molecular and Polymer Assemblies... 

Recommendations on additional aspects of macromolecular nomenclature such as that of regular double-strand (ladder and spiro) and irregular single-strand organic polymers continue to be published in Pure and Applied Chemistry. Recommendations on naming nonlinear polymers and polymer assemblies (networks, blends, complexes, etc) are expected to be issued in the near future. 

Chromophore—Polymer Assemblies for Nonlinear Optical Materials... 

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