Sequence polymers

In order to ensue a clear presentation of the results the authors decided to segregate both synthetic principles All synthetic strategies developed from the multifunctional condensations of Stille and Marvel were assigned to this general type of reaction. At the same time the first multistep sequences (polymer-analogous cyclization of poly(methyl vinyl ketone) and polyacrylonitrile) are used as point of reference for the classification of the other type of synthesis (stepwise procedures). 

RAFT is the newest methodology and is performed by adding a thioester compound to a conventional free-radical polymerisation, as shown in Figure 4(b). The mechanism of RAFT polymerisation is envisaged to involve a series of addition-fragmentation sequences. Polymers with narrow molecular weight distribution can be made, and block or star polymers are also possible. 

Oh-Uchi SK, Yang JY, LeeJS, MurakawaY, and Narita M. Only Weak Dependence of the Protected Peptides Solubility in Organic Solvent on their Amino Acid Sequence. Polym/1996 28 1033-1038. 

The essential features of protein lattice models were described in Section 10.3.1. Protein folding is usually studied with a seif-avoiding chain on a cubic lattice with one residue per vertex and a simple interaction model which only includes interactions between pairs of monomers that are in contact on the lattice but are not successive in the sequence. Polymers of length 27 that occupy all sites of a 3 x 3 x 3 cube are particularly popular. There are nearly... 

For their research on the effects of fluorine substitution on peptide conformations (see below), Zondlo and coworkers developed a divergent synthesis of peptides (Thr-Tyr-X-Asp) (TYXN) containing an internal substituted Tyr-X (X = Pro or substituted Pro) sequence. Polymer-supported peptides containing hydroxyproline were prepared, modified, and released by standard acidic cleavage and deprotection. This is summarized in Fig. 3.13. 

Sequence polymers synthetic amino acid polymers, consisting of multiple repeats of one short sequence. In contrast to Polyamino acids (see), Sp. contain more than one type of amino acid residue. They are prepared by the self condensation of activated peptides (di to hepta). p-Nitrophenyl esters (see Peptid ) and other activated esters can be u ring closure is avoided by using high concentrations of reactants in polar solvents in the presence of organic bases. The average of the resulting S.p. are considerably lower than those of the synthetic poly-... 

Zhang, F.J., Song, M., Lu, T.J., Liir, J.P., He, T.B., The polydispersity of ethylene sequence in metallocene ethylene/alpha-olefin copolymers HI crystallization and melting behavior of short ethylene sequence, Polymer 2002, 43 1 453-1460. 

Various structures of SPI materials were recently studied [103,104]. For instance, Genies and co-workers [78] synthesized SPI membranes with random and sequence polymer, but did not achieve the high proton conductivity required for practical application of fuel ceU. Guo and co-workers [103] and Fang and co-workers [104] also investigated the relationship between the structure of SPI and its properties in detail. It was revealed that the more flexible the main chain, the more the man-brane s hydrolysis stability was improved. Finally, Woo and co-workers [77] found that proton conductivity and methanol permeability of SPI membranes do not depend on the distance between water clusters, but only on the size of water cluster in SPI membrane. 

Lv A, Deng X-X, Li L, Li Z-L, Wang Y-Z, Du F-S, Li Z-C (2013) Facile synthesis of multiblock copolymers containing poly(ester-amide) segments with an ordered side group sequence. Polym Chem 4(13) 3659-3662... 

Zuc 1994a Zuckermann, R.N. and Goff, D.A., Synthesis of (N-Substituted)-Glycine Polymers of Defined Length and Sequence, Polymer Preprints, 35 (1994) 975-976. 

Inspired by our bodies ability to heal, self-healing materials have the ability to repair themselves when they are damaged. In the literature discussed in other chapters in this book, supramolecular chemistry as well as sample conditions were varied in order to examine whether gel rheological behavior is dependent on factors like polymer functionality sequence, polymer concentration, temperature and pH. 

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