Poly ionic macromolecules

The 3H-poly-Phe peptides produced in these experiments will be isolated by exploiting their ability to precipitate in a solution containing 5% trichloroacetic acid (TCA). Strong acids such as TCA are effective in inducing the precipitation of all ionic macromolecules. Thus, the proteins, tRNA, and mRNA present in the translation reactions will all become insoluble on the addition of 5% TCA. Remember that there are three individual pools of 3H-Phe present in this ongoing translation reaction the free 3H-Phe, the 3H-Phe covalently linked to the tRNA, and the 3H-Phe that has been incorporated into the growing peptide. The free 3H-Phe will remain soluble in 5% TCA due to its small size, and therefore will not be present in the precipitate. The 3H-Phe covalently linked to the 3 end of the tRNA, however, will be insoluble in 5% TCA and will be present in the precipitate (Fig. 23-9). If this 3H aminoacyl tRNA pool is not removed from the precipitate, you will overestimate the amount of 311-Phe that was incorporated into the peptide when the reactions are subjected to scintillation counting. 

Xiao S, Lu X, Lu Q (2007) Photosensitive polymer from ionic self-assembly of azobenzene dye and poly(ionic liquid) and its alignment characteristic toward liquid crystal molecules. Macromolecules 40 7944—7950... 

J. Tang, M. Radosz, Y. Shen, (2008) "Poly(ionic liquid)s as optically transparent microwave-absorbing materials." Macromolecules, 41,493-4%. 

TA4 Tang, J., Srrrr, W., Tang, H., Radosz, M., and Shen, Y., Enhanced CO2 absorption of poly(ionic ]iquid)s. Macromolecules, 38, 2037, 2005. 

Yuan J, Antonietti M (2011) Poly(ionic liquid) latexes prepared by dispersion polymerization of ionic liquid monomers. Macromolecules 44 744—750... 

Van der Waals complexes result from association of non-ionic macromolecules via dipole-induced dipole or dispersion interactions. For example, the macromolecular complex of isotactic and syndiotactic poly(methyl methacrylate) forms as a result of van der Waals interactions [1]. Similar mechanisms give rise to complexes involving copolymers of poly(methacrylic acid) (PMAA) with poly(methyl methacrylate) (PMMA) [1,2]. 

Amajjahe, S. Ritter, H. (2008a). Supramolecular controlled pseudo-LCST effects of cyclodextrin-complexed poly(ionic liquids). Macromolecules, 41,3250-3253. 

Allcock, H. R., and Kwon, S., An ionically-crosslinkable poly-phosphazene Poly[di(carboxylatophenoxy)phosphazene] and its hydrogels and membranes. Macromolecules. 22. 75, 1989. 

AB cements are not only formulated from relatively small ions with well defined hydration numbers. They may also be prepared from macromolecules which dissolve in water to give multiply charged species known as polyelectrolytes. Cements which fall into this category are the zinc polycarboxylates and the glass-ionomers, the polyelectrolytes being poly(acrylic acid) or acrylic add copolymers. The interaction of such polymers is a complicated topic, and one which is of wide importance to a number of scientific disciplines. Molyneux (1975) has highlighted the fact that these substances form the focal point of three complex and contentious territories of sdence , namely aqueous systems, ionic systems and polymeric systems. 

Tliis description combined with Table 2, however, does not necessarily mean that the actual variation of pKa of the relevant group in the material is from ca.10 to ca.5. The actual pKa of the ionic groups in materials could be altered significantly due to the electrostatic interaction between these groups. This electrostatic interaction, on the other hand, could vary significantly according to the conformation that constituent macromolecules take, for example, the secondary structure of poly(amino acid). 

For another poly-p-phenylene system it is reported that aggregation to defined cylindrical micelles occurs in aqueous solution [15, 16]. In these systems the ionic groups (sulfonate groups) are directly attached to the phenyl-ene units. Moreover, long n-alkyl side chains are attached to the PPP backbone. The polyelectrolytes PPP-1 considered here have the trialkyl ammonium groups linked to the backbone via a hexamethylene spacer. It is obvious that the spatial requirement of these substituents prevents the macromolecules from forming such aggregates. 

Winey, K.I. Laurer, J.H. Kirkmeyer, B.P. Ionic aggregates in partially Zn-neutralized poly-(ethylene-ran-methacrylic acid) ionomers shape, size and size distribution. Macromolecules 2000, 33, 507. 

Laurer, J.H. Winey, K.I. Direct imaging of ionic aggregates in Zn-neutralized poly(ethylene-ran-methacrylic acid) copolymers. Macromolecules 1998, 31, 9106. 

Kirkmeyer, B.P. Taubert, A. Kim, J.-S. Winey, K.I. Vesicular ionic aggregates in poly(styrene-ran-methacrylic acid) ionomers neutralized with Cs. Macromolecules 2002, 35, 2648. 

Sauer, B.B. McLean, R.S. AFM and x-ray studies of crystal and ionic domain morphology in poly(ethylene-co-methacrylic acid) ionomers. Macromolecules 2000, 33, 7939. 

Bruno KR, Mattice WL. Long-range intermolecular interactions in dilute aqueous solutions of ionized poly(L-lysine) at low ionic strength. Macromolecules 1992 25 327-330. 

Most macromolecules when dissolved in salt solutions acquire charges that are shielded by an atmosphere of counterions. This ion atmosphere affects the diffusion coefficient of the macromolecule and hence the light-scattering time-correlation function. Electrolyte solutions are discussed in Chapters 9 and 13. Recent measurements of diffusion coefficients have been made by several groups. Lee and Schurr (1974) have studied poly-L-lysine-HBr. Schleich and Yeh (1973) have performed similar studies on poly-L-proline. Raj and Flygare (1974) have studied bovine serum albumin (BSA) and find that at high ionic strength and low pH the diffusion constant decreases. This they attribute to the expansion of the molecule. 

Modern theories of silicate structure do not assign the cations such a passive role, but assume that they are site bound in well-defined regions around the macromolecule. This is essentially similar to co-ordinating ions with ionic organic polymers, for example in the calcium or zinc salts of poly(acrylic acid). 

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