Along polymer chains

These appHcations are mosdy examples of homogeneous catalysis. Coordination catalysts that are attached to polymers via phosphine, siloxy, or other side chains have also shown promise. The catalytic specificity is often modified by such immobilization. Metal enzymes are, from this point of view, anchored coordination catalysts immobilized by the protein chains. Even multistep syntheses are possible using alternating catalysts along polymer chains. Other polynuclear coordination species, such as the homopoly and heteropoly ions, also have appHcations in reaction catalysis. 

Figure 2.15 line repetition symmetry groups and corresponding sequences of torsion angles for cis and trails polydienes. Position of mirror planes (m), inversion centers (i), and binary axes (2) along polymer chain are also indicated. Torsion angle of single bond, CHA-CHA, is assumed to be trails (T) in both cis and lruns polydienes. 

Polymers Chain dynamics Local viscosity in polymer environments Molecular orientation in solid polymers Migration of excitation energy along polymer chains... 

Chemical reaction that leads to the formation of ring structures in or from polymer chains. Note 1 Examples of cyclization along polymer chains are (a) cyclization of... 

An extension of polymer cross linking to ion exchange resins would make it possible to form heavily cross linked resins after functional groups had been added. Another corollary of this idea would be to use radiation to activate sites along polymer chains, thus permitting the grafting of active groups. 

Fig. 3 Dependence of the decimal logarithm of irreducible correlator tun = rnlw) -on distance n along polymer chain for macromolecules of equimolar composition at the values of parameters (Eq. 20) h = 70, h = 0.01. Curves are presented for macromolecules whose length is Z = 2 x lO (1) 6 x lO (2) 12 x lO (3). Thin lines represent asymptotic expressions at n n. Volume fraction of monomeric units in the globule is = 0.9...

Electrical conductivity in PPy involves the movement of positively charged carriers and/or electrons along polymer chains and the hopping of these carriers between chains. It is generally believed that the intrachain hopping resistance is much greater than the interchain transport resistance. 

Programming Secondary Interactions along Polymer Chains 561... 

Fig. 2.13 Illustration of sequence regularities of stereo-isomers along polymer chains with three typical cases for isotactic, syndiotactic and atactic sequences...

Quasi-One-Dimensional Band Dispersion Along Polymer Chains... 

There is generally an increase in the ratio IdIIm as the molecular weight of the polymer increases. This has been taken as a confirmation of the energy migration along polymer chains. 

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