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Chemical structure of block

FIGURE S.1 Chemical structure of block copolymeric thermoplastic elastomers (TPEs) (a) styrenic, (b) COPE, (c) thermoplastic pol)oirethane, and (d) thermoplastic polyamide. [Pg.106]

Fig. 1.2 Chemical structures of blocks from which copolymers are commonly constructed. Fig. 1.2 Chemical structures of blocks from which copolymers are commonly constructed.
Chart 11.12 General chemical structures of block copolymers and graft copolymers consisting of monomer units A and B. [Pg.324]

The chemical structure of block copolymers is given by the number of blocks, their sequence, and their length, as is discussed in Fig. 1.19 and Sect. 3.4.1. The structure of a diblock copolymer poly(styrene-fc/oc -l, 4-butadiene) of type AB, for example, can have the following chemical structure ... [Pg.747]

Figure 29 Representative scheme for the preparation of organic-inorganic hybrid nanocylinders through bulk self-assembly followed by cross-linking via sol-gel. (Left) Chemical structure of block copolymers used. (Right) TEM images of films and nanostructures obtained from a series of PTEPM-b-PS block copolymers. Reproduced with permission from Zhang, K. Gao, L. Chen, Y. M. Macromolecules 2001, 40,5916-5922, and Zhang, K. Gao, L. Chen, Y. M. Macromolecules 2m, 41 (5), 1800-1807. ... Figure 29 Representative scheme for the preparation of organic-inorganic hybrid nanocylinders through bulk self-assembly followed by cross-linking via sol-gel. (Left) Chemical structure of block copolymers used. (Right) TEM images of films and nanostructures obtained from a series of PTEPM-b-PS block copolymers. Reproduced with permission from Zhang, K. Gao, L. Chen, Y. M. Macromolecules 2001, 40,5916-5922, and Zhang, K. Gao, L. Chen, Y. M. Macromolecules 2m, 41 (5), 1800-1807. ...
Figure 6.259 Chemical structures of blocks used to make PPAs. Figure 6.259 Chemical structures of blocks used to make PPAs.
Figure42 Chemical structures of rocf-coil block copolymers with short, monodisperse rod segments, (a) Block copolymer with polyisoprene and a rod segment built of an azo dye and a rigid monomer and (b) miniaturized triblocks from Stupp and coworkers, (c) and (d) Show the chemical structures of block copolymers with either poly(propylene oxide) or poly(ethylene oxide) and a short rod segment as reported by Lee et al. Figure42 Chemical structures of rocf-coil block copolymers with short, monodisperse rod segments, (a) Block copolymer with polyisoprene and a rod segment built of an azo dye and a rigid monomer and (b) miniaturized triblocks from Stupp and coworkers, (c) and (d) Show the chemical structures of block copolymers with either poly(propylene oxide) or poly(ethylene oxide) and a short rod segment as reported by Lee et al.
See also PBT degradation structure and properties of, 44-46 synthesis of, 106, 191 Polycaprolactam (PCA), 530, 541 Poly(e-caprolactone) (CAPA, PCL), 28, 42, 86. See also PCL degradation OH-terminated, 98-99 Polycaprolactones, 213 Poly(carbo[dimethyl]silane)s, 450, 451 Polycarbonate glycols, 207 Polycarbonate-polysulfone block copolymer, 360 Polycarbonates, 213 chemical structure of, 5 Polycarbosilanes, 450-456 Poly(chlorocarbosilanes), 454 Polycondensations, 57, 100 Poly(l,4-cyclohexylenedimethylene terephthalate) (PCT), 25 Polydimethyl siloxanes, 4 Poly(dioxanone) (PDO), 27 Poly (4,4 -dipheny lpheny lpho sphine oxide) (PAPO), 347 Polydispersity, 57 Polydispersity index, 444 Poly(D-lactic acid) (PDLA), 41 Poly(DL-lactic acid) (PDLLA), 42 Polyester amides, 18 Polyester-based networks, 58-60 Polyester carbonates, 18 Polyester-ether block copolymers, 20 Polyester-ethers, 26... [Pg.595]

Triblock copolymers of ABA type, where B is the central elastomeric block and A is the rigid end-block, are well-known commercially available polymers [7,8]. The chemical structures of some common TPEs based on styrenic block copolymers are given in Eigure 5.1. Synthesis of such ABA-type polymers can be achieved by three routes [9] ... [Pg.104]

Fig. 2 PICsomes formed from oppositely charged building blocks, (a) Chemical structures of the hybrid polypeptides for PICsomes and scheme of the PICsome preparation, (b) Cryo-TEM image of 100-nm-sized PICsomes (scale bar 50 run). Arrows indicate vesicle walls. Adapted from [70] with permission. Copyright 2010 American Chemical Society... Fig. 2 PICsomes formed from oppositely charged building blocks, (a) Chemical structures of the hybrid polypeptides for PICsomes and scheme of the PICsome preparation, (b) Cryo-TEM image of 100-nm-sized PICsomes (scale bar 50 run). Arrows indicate vesicle walls. Adapted from [70] with permission. Copyright 2010 American Chemical Society...
Fig. 5 Polypeptide vesicles demonstrate the ability to utilize the EPR effect, (a) Chemical structure of the amphiphilic block polypeptide PSar-b-PMLG. (b) Fluorescence image using fluorescently labeled PEG. Fluorescence is not observed in the cancer site although accumulation is observed in the bladder, (c) Fluorescence image using ICG-labeled vesicles, showing evidence of vesicle accumulation due to the EPR effect. Adapted from [41] with permission. Copyright 2008 American Chemical Society... Fig. 5 Polypeptide vesicles demonstrate the ability to utilize the EPR effect, (a) Chemical structure of the amphiphilic block polypeptide PSar-b-PMLG. (b) Fluorescence image using fluorescently labeled PEG. Fluorescence is not observed in the cancer site although accumulation is observed in the bladder, (c) Fluorescence image using ICG-labeled vesicles, showing evidence of vesicle accumulation due to the EPR effect. Adapted from [41] with permission. Copyright 2008 American Chemical Society...
This paper will not described the chemical structure of pectins which is a difficult problem [1] even if the physical properties in solution and ability to form gel must be directly related with the distribution of the units along the chain. The functional properties of pectins are not only related to the neutral sugar content (up to 15 %) but also to the distribution of structural blocks having very different contibutions. [Pg.22]

Short chain branches are frequently introduced into polymers by copolymerization. The chemical structure of the comonomer controls the type and length of the short chain branch. The polymerization catalyst, reaction conditions, and comonomer content in the reaction medium determine the probability of finding a branch at any particular location along a chain. Comonomers, and hence the short chain branches derived from them, can be introduced at random or as blocks. [Pg.33]

Figure 21.4 General chemical structure of styrene block co-butadiene... Figure 21.4 General chemical structure of styrene block co-butadiene...
An exhaustive theoretical characterization of the chemical structure of poly-disperse block copolymers suggests knowledge of the distributions of ... [Pg.190]

A special class ofblock copolymers with blocks of very different polarity is known as amphiphilic (Figure 10.1). In general, the word amphiphile is used to describe molecules that stabilize the oil-water interface (e.g., surfactants). To a certain extent, amphiphilic block copolymers allow the generalization of amphi-philicity. This means that molecules can be designed that stabilize not only the oil-water interface but any interface between different materials with different cohesion energies or surface tensions (e.g., water-gas, oil-gas, polymer-metal, or polymer-polymerinterfaces). This approach is straightforward, since the wide variability of the chemical structure of polymers allows fine and specific adjustment of both polymer parts to any particular stabilization problem. [Pg.151]

Fig. 14 TEM micrographs showing a vesicles, b, c micellar fibers, and d superhelices from a PEO-PMPS block copolymer (the chemical structure of this copolymer is represented below the micrographs). Reprinted with permission from [238]. Copyright (2001) American Chemical Society... Fig. 14 TEM micrographs showing a vesicles, b, c micellar fibers, and d superhelices from a PEO-PMPS block copolymer (the chemical structure of this copolymer is represented below the micrographs). Reprinted with permission from [238]. Copyright (2001) American Chemical Society...
A complete description of the synthetic methodology and the characterization of the obtained metallosupramolecular block copolymers was reported in a recent paper [324]. These compounds have been referred to as metallosupramolecular block copolymers and designated by the acronym Ax-[Ru]-By, where A and B are the two different polymer blocks, -[Ru]- denotes the fczs-2,2/ 6/,2/terpyridine-ruthenium(II) linkage between the A and B blocks, and x and y represent the average degree of polymerization of the A and B blocks, respectively. The chemical structure of a PEB-[Ru]-PEO metallosupramolecular copolymer is depicted in Fig. 23. [Pg.135]

Preparative and analytical HPLC were carried out in an ODS column using gradient elution. The gradient was composed of methanol, water and formic acid. The chemical structures of the new pigments were elucidated by UV-VIS, 2D NMR and LC-MS. MS conditions were capillary 3 kV, cone 30 and 60 V, extractor 7 V, sources block temperature 120°C, desolvation temperature 150°C [257],The chromatographic profile of the SEC fraction containing the new pigments is shown in Fig. 2.116. The chemical structures of the new derivatives identified by various spectroscopic techniques are shown in Fig. 2.117. [Pg.273]

Snyder and coworkers [6] reviewed the dependence of silanol interactions on the chemical structure of the interacting base. Deductions were based on data of the relative efficacy of amine silanol blocking agents that were more popular at the time the stronger the deactivation effect of the modifier, presumably the stronger its binding to silanols. Stronger interaction of an amine or quaternary ammonium compound was said to be favored by... [Pg.330]

Figure 4. Chemical structure of sulfonated SEBS block copolymer. Figure 4. Chemical structure of sulfonated SEBS block copolymer.
Fig. 6.5 Chemical structure of polystyrene-block-poly(m-vinyltri phenyl phosphine) (PS-b-PPH)... Fig. 6.5 Chemical structure of polystyrene-block-poly(m-vinyltri phenyl phosphine) (PS-b-PPH)...
The chemical structure of p-block-ers also determines their pharmacokinetic properties. Except for hydrophilic representatives (atenolol), p-sympatho-lytics are completely absorbed from the intestines and subsequently undergo presystemic elimination to a major extent (A). [Pg.94]


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Block structures

Block structuring

Chemical structure of di-block copolymer

Of chemical structures

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