Similarity poly

The two structures appear very similar. Poly( 1,2-propylene adipate) has the same basic structure as poly(ethylene adipate), except for a pendant methyl group. This pendant methyl group on the poly( 1,2-propylene adipate) makes a large difference, however. Poly( 1,2-propylene adipate) has no crystalline melting point. Trappe theorizes that the pendant methyl prevents chain packing and therefore, prevents crystallization [42]. 

An unambiguous stereochemical assignment of the alpha methyl absorptions is difficult to make. On the basis of the similarity of the observed spectra to the closely similar poly (alphamethylstyrene) ( , 10, Jl ), it is tempting to assign the upfield and downfield absorptions to syndiotactic and isotactic triads, respectively. This assignment would be supported by the 300 and 600 MHz 1h spectra of tetramer [14] that suggest predominant (>90%) formation of a racemic dyad. 

Similarly, poly-p-diphenylphosphinostyrene has been prepared by polymerizing the monomeric material with styrene and divinylbenzene ... 

Similarly, poly (p-formyloxy styrene) (IV) can be prepared by formylation of poly(p-hydroxystyrene) using formic acid-acetic anhydride mixture as a formylating agent (Scheme 4). The formylation reaction is best... 

This process has, however, not yet found industrial application. Similarly, poly-isoprenoids can be epoxidized regioselectively in co-position to functional groups (Table 4, No. 16-19) Polymer-bound mediators can also be used in this... 

Initial studies58 had indicated that 1-glycopyranosyl nucleosides prepared by the mercuri procedure are identical with those prepared by the Hilbert-Johnson method, when similar poly-O-acylglycosyl halides are employed. The applicability of the mercuri procedure to the synthesis of 1-aldopento-furanosyl nucleosides was demonstrated by the preparation of 5 -methyl-uridine (LIV). Condensation of dithyminylmercury (LI) with tri-O-benzoyl-... 

In the second approach to self-assembly of polymer-silica nanocomposites, polymerizable surfactants are employed both to direct self-assembly into ordered mesophases and to serve as organic monomers which can be subsequently polymerized. For instance, Brinker et al. developed nonionic surfactants incorporating diacy-telene groups which could be polymerized upon irradiation by UV light.68 69 Similarly, poly(thiophene)70 and poly(pyrrole)71 have been successfully integrated into silica nanostructures in this manner. Importantly, this in situ polymerization produces isolated molecular wires, rather than clustered bundles of conductive polymer.70... 

Polypropylene imine) dendrimers (see Scheme 1 for structure) have been constructed step by step onto an amine functionalized polystyrene [38, 130, 131]. The challenge in this synthesis is finding conditions for the polypropylene imine) synthesis under which the low MW polystyrene (MW=3200) is soluble [38]. Similar poly(imine) dendrimers with carboxylic acid end groups have also been prepared [130]. The polypropylene imine) dendrimer has also been synthesized on an amino-terminated poly(2-methyl-2-oxazoline) [132]. 

Muzafarov, Golly and Moller 646 have prepared similar poly(alkoxysilanes) that are easily hydrolyzed under acidic conditions and are thus biodegradable. Additional branched organosilicon polymers of interest include those of Ishikawa et al. fi4c ... 

Photoconductivity has been observed on polymers to which the active polynuclear aromatic groups had been added by chemical attachment. For example, poly(L-lysine) with anthracene groups is claimed to be useful in electrophotography65. Similarly, poly(p-alkyl glutamates) with the attached 9-anthryl, 9-anthryl-methyl and other groups were claimed to be photoconductive66. ... 

Similarly, poly(butadiene-g-styrene) represents the graft copolymer in Equation 2, where it is understood that the symbol -g- means graft copolymer, the first indicated species forms the backbone, and the second the side chain. Similarly, the symbol -co- stands for a random copolymer, -a- for an alternating copolymer, and occasionally the symbol -cl- is used for crosslinked systems. 

Today, Lobelia inflata (Indian tobacco) or its derivatives (lobeline hydrochloride and lobeline sulfate) are used for much the same purpose and are marketed throughout Europe in a number of multi-ingredient preparations 73 Similarly, Poly gala senega (Seneca snakeroot), listed in the supply table as an expectorant, is widely marketed throughout Europe and South Africa for respiratory-tract complaints 7 A popularly prescribed diuretic on the supply table was Juniperus communis (juniper) it is still widely manufactured and dispensed for the same purpose today75... 

Composites of polypyrrole and poly(vinyl chloride) have been prepared by several groups (64-67). Polythiophene-poly(vinyl chloride) composites have also been prepared (68). The electropolymerization of pyrrole on poly(vinyl chloride)-coated electrodes yielded composites with mechanical properties (tensile strength, percent elongation at break, percent elongation at yield) similar to poly(vinyl chloride) (65) but with a conductivity of 5-50 S/cm, which is only slightly inferior to polypyrrole (30-60 S/cm) prepared under similar conditions. In addition, the environmental stability was enhanced. Morphological studies (69) showed that the polypyrrole was not uniformly distributed in the film and had polypyrrole-rich layers next to the electrode. Similarly, poly(vinyl alcohol) (70) poly[(vinylidine chloride)-co-(trifluoroethylene)] (69) and brominated poly(vinyl carbazole) (71) have been used as the matrix polymers. The chemical polymerization of pyrrole in a poly(vinyl alcohol) matrix by ferric chloride and potassium ferricyanide also yielded conducting composites with conductivities of 10 S/cm (72-74). 

Similarly, poly(trichlorobutadiene)s contain 3,4-connected links, along with predominating 1,4-links [37], that will afford allenic or acetylenic pendants during dehydrohalogenation (Scheme 12.10). 

Similarly, poly(dimethylsiloxane) (pDMS), an inorganic polymer, has been incorporated into block copolymers using a functionalization reaction. Maty-jaszewski et al. used commercially available hydrosilyl or vinylsilyl terminated... 

See Figure 17.7 for two simple examples of the utilization of the shortcut described above. Polyoxytrimethylene can be treated formally as the alternating copolymer of ethylene and oxymethylene. Similarly, poly(p-xylylene) can be treated formally as the alternating copolymer... 

Hung and Chang [83] have synthesised a number of similar poly(imide-car-bonate)s with an aromatic unit replacing one of the spacers, with structure 25. 

The first enzyme-catalyzed ROP was found for e-CL and 8-VL by two independent groups in 1993 [12, 13]. ROP of e-CL was performed in bulk at 75 °C for 10 days using Pseudomonas fluorescens as a catalyst, and poly(e-CL) was formed in 92% yield with molecular weight M of 7700 and Mw/Mn = 2.4. Similarly, poly(8-VL) was obtained at 60 °C with M of 1900 and Mw/Mn =3.0. Further investigation of obtained polyesters (terminal structure of a carboxylic acid group at one end and a hydroxyl group at the other) revealed that ROP was initiated by water. 

Polymers containing aryl groups also react efBdently with metal atoms to yield bis(arene)metal(0) complexes within the polymer chain . Thus, poly(methylphenyl-siloxanes) react at 0°C as a liquid with Ti, V, Cr, Mo and W atoms to give high yields of colored bis( / -arene)metal complexes. In contrast Co, Fe and Ni atoms )deld only metal slurries. Similarly, poly(oxyphenylene) and polystyrene (in a solvent) react with V and Cr atoms to yield colored solutions . By adjusting the metal-atom flux, small, polymer-supported Ti and Mo clusters can be prepared . In some cases the com-plexed metal atoms spontaneously migrate through the polymer fluid to form dimers . 

Similarly, poly-(.S )-leucine and other polymeric amino acids with definite chain length were prepared and used in the same way28. Poly-(5)-leucinc has also been used in enantioselective hydroesterifications (Section D. 1.5.8.). 

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