Polymer ligands

Additional ligands, (I), and ringopening polymerization ligand polymers, (II), prepared in the current application are illustrated below. 

This type of selectivity originates solely from steric interactions between the auxiliary ligands, polymer chain, and the incoming propene. It was first explained qualitatively by means of visualization of the structure of the catalyst precursors. A more quantitative approach led naturally to molecular mechanics models in order to explain and even predict the stereospecificity of catalysts with different ligand environments. Due to the limitations of MM models to describe metallocene complexes as well as bond breaking and bond formation processes (see Section 3.1.2.1), the models were initially based on some rigid core structures derived from the measured structures, e. g., of the dichloride precursors [25, 26]. In order to achieve more accurate results, core structures, calculated by ab initio methods, were employed later. A further step in this direction is the joint description of the... 

IrCla initiation. The unexpected isotactic bias on polymers of is interpreted in terms of control of R or S configuration at the ring carbon attached to ligand. Polymers of 1 show no cis/trans blockiness falls from 0.4 to 0.2 with dilution of monomer (2). 

The last series of examples of diisocyanide-containing polymers is the mixed-ligand polymers where two different bridging ligands are used to hold the polymer backbone. The polymers are of the general formula (Au—C = C—R—C=C—Au—C=N—R —N=C) where the list for R and R is given in Table 8.2.73,74... 

Equation 22 predicts that the nonideality term for the acid dissociation equilibria of weak polyelectrolytes can directly be used to evaluate the (K mt function, i.e., if log( M)app is plotted against ApA, a straight line with the slope Z is expected, whose intercept at the y axis corresponds to log( [5-7], It should be noted again that (1) the concurrent measurement of pH and pM at each titration point is needed for this analysis and (2) the ratio of the total concentrations of metal ion to ligand polymer should be kept as low as possible for the perturbation due to complexation on acid dissociation equilibria to be neglected. 

Figure 1. Radiolytic reduction of metal ions. After their formation, the atoms coalesce and also become associated with excess metal ions. The clusters can be stabilized by ligands, polymers or supports. The cluster redox potential increases with the nuclearity n. The smallest oligomers can undergo corrosion by...

Ogris M, et al. (2001). DNA/polyethylenimine transfection particles influence of ligands, polymer size, and PEGylation on internalization and gene expression. AAPS PharmSci. 3 e21. 

The self-assembly of metal-Ugand-based architectures at surfaces is a promising and versatile method for the fabrication of 2D metal-ion arrays. Most of those experiments have been carried out under UHV conditions showing the remarkable potential of this approach [15]. Under ambient conditions, only in a few occasions metal-ligand polymers [16] or 2D grids [17-19] are formed. 

From Fig. 7.7, it can be noticed that the variation of electrical properties of paper sheets with changing the type of ligand polymer was greatly noticed at low frequency [0.5 kHz]. Therefore, the values of dielectric measurements at 0.5 kHz were recorded in Table 7.13, together with their mechanical properties. 

Po %)e interpretation Solid transibon ormekiitg Ddtydration Decomposition (e.g. lost of ligand) Polymer crystallization Some solid transitions Docomposition (oxidatKNi) Glass transition Electricat disturbanc... 

III. APPLICATION OF THERMODYNAMIC PRINCIPLES TO LIGAND-POLYMER BINDING... 

Figure 13, Seaming electron micrographs of a large particle of the mixed ligand polymer (left 1000 X, right 3000 )Q. (Reproduced with permission from reference 20. Copyright 2007 Elsevier.)...

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