Structural analysis, of poly

BD Barr-Howell, NA Peppas. Structural analysis of poly(2-hydroxyethyl methacrylate) microparticles. Eur Polym J 23 591-596, 1987. 

M. Leclerc, F.M. Diaz, and G. Wegner, Structural analysis of poly(3-alkylthiophenes), Makromol. Chem., 190 3105-3116, 1989. 

Crystal structure analysis of poly(p-xylylene) (PPX) P-form [2,25]... 

On the other hand, we reexamined in detail the ring size of the cyclic structural units of poly-AA s by means of IR, 1H-NMR, and C-NMR spectroscopy these analytical procedures were applied to the structural analysis of poly-AA, the poly(acrylic acid) derived from hydrolysis of the poly-AA, and the poly(methyl acrylate) obtained by subsequent esterification of the poly(acryl-ic acid) in comparison with the corresponding model polymers of five- or six-membered ring structure. Then, we investigated in detail the effects of polymerization conditions on the ring size of poly-AA s, i.e., on the intramolecular addition modes in the cyclopolymerization of AA since five- or six-membered ring anhydride structure can be formed via intramolecular hh or ht addition of the uncyclized radical to the internal double bond(22,23). 

This chapter covers the applications of Fourier transform infrared (FTIR) and Raman spectroscopy to the characterization of water-soluble polymers. The structural analysis of poly(oxyethylene), poly ethylene glycol), poly methacrylic acid), and poly acrylic acid), and the interactions of selected polymers with solvents and surfactants are presented. Structural features of these compounds in the crystalline and melt states are compared with their structural features upon dissolution in aqueous solvents. Special emphasis is given to the recent studies of the interactions between water-soluble polymers or copolymers and solvents or surfactants. New experimental approaches and the sensitivities of both FTIR and Raman spectroscopy to monitor such interactions are presented. 

R 723 S. Maeda, T. Mori, H. Kunimoto and C. Sasaki, Molecular Structural Analysis of Poly( -Lysine) Derived from Streptomyces , Kobunshi Kako, 2003,52,516... 

Wasanasuk, K., Tashiro, K., Hanesaka, M. et al. (2011) Crystal structure analysis of poly(L-lactic add) a form based on the dimensional wide-angle synchrotoron X-ray and neutron diffraction measurements. 

A few years earlier, in 1991, Williams et al. [22] had performed the structural analysis of poly(tetramethyl-p-silphenylene siloxane)-poly(di-methylsiloxane) copolymers (TMPS-DMS copolymers) by Si NMR. These copolymers were obtained by the condensation of bis-hydroxy(tetramethyl-p-silphenylene siloxane) 1 with a, tw-dihydroxy polydimethyl oligosiloxanes, in the presence of a guanidinium catalyst (cf. Scheme 8) ... 

Journal of Polymer Science Polymer Physics Edition 36, No.14, Oct.l998,p.2471-82 STRUCTURAL ANALYSIS OF POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE) FIBERS PREPARED BY DRAWING AND ANNEALING PROCESSES Furuhashi Y Ito H Kikutani T Yamamoto T Kimizu M Cakmak M... 

Bolognesi, A., M. Gatellani, S. Destri, and W. Porzio. 1991. Evidence of chain planarity in PAT Low-temperature structural analysis of poly(3-decylthiophene). Makromol Chem Rapid Commun 12 9. 

Detailed structural analysis of poly(vinyl acetate) has revealed that hydrogen abstraction from the acetyl group is the predominant chain transfer mechanism (285). Abstraction from the methine hydrogen of the main chain leads to a small amoimt of branching (286,287). 

A. Breitenbach and T. Kissel, Biodegradable comb polyesters Part 1 synthesis, characterization and structural analysis of poly (lactide) and poly (lactide-co-glycolide) grafted onto water-soluble poly (vinylalcohol) as backbone. Polymer, 39(14), 3261-3271 (1998). 

NEUTRON STRUCTURE ANALYSIS OF POLY (VINYL ALCOHOL)(7)... 

Guo L., Lee J.H., Beaucage, G. Structural analysis of poly(dimethylsiloxane) modified siUca xerogels. J. Non-Cryst. Solids 1999 243 61-69... 

Fig. 13. (g+aaaag aaa) conformation of crystalline erythrodiisotactic poly(l,2-dimethyltetra-methylene) according to an X-ray structural analysis of Natta el al., Ref. z8>)... 

Crystal structure analysis for poly(p-benzoic acid) whisker [40] and stmctural study of stacking faults in s5mdiotactic pol5 ropylene [41] were carried out. 

A study of methods for controlling the grafting sites of polystyrene polymers may serve as an example for the quantitative and structural analysis of the site of lithiation. Trimethylsilyl chloride serves as the quenching agent owing to the low incidence of side reactions besides metal replacement. Thus, on varying the conditions of metallation of low molecular weight polystyrene (409) and poly(4-methylstyrene) (410), aromatic and... 

Lang M, Wong RP, Chu C-C (2002) Synthesis and structural analysis of functionalized poly (s-caprolactone)-based three arm star polymers. J Polym Sci A Polym Chem 40 1127-1141... 

Matsumoto K, Kondo K., Ota T., Kawashima A., Kitamura, K, Ishida T. (2006) Binding model of novel 1-substituted quinazoUne derivatives to poly (ADP-ribose) polymerase-catalytic domain, revealed by X-ray crystal structure analysis of complexes. Biochi. et Biophy. Acta. 1764,913-919. 

Few neutron or electron diffraction studies have been reported, although the neutron structure analysis of substituted poly(benzobisthiazole) and poly(benzobisoxazole) derivatives of 19 and 5 has been reported and the torsion angle between the benzobisthiazole and phenyl rings was shown to be 7.2° larger than that determined from X-ray methods <1999MM4010, 2001MM2012>. 

The 13C chemical shift contour map for the Cp carbon of the L-alanine residue in peptides and polypeptides was made as a function of the dihedral angles(, W) by using the experimental data. Also, the corresponding calculated map was made by using the ab initio coupled Hartree-Fock method with the gauge included atomic orbitals(GIAO-CHF). From these results, it was found that the calculated map explains the chemical shift behavior of the a-helix and p-sheet forms in poly(L-alanine) and some proteins. This suggests that the calculated map is applicable to the structural analysis of proteins with complicated structure. 

From these results, it was found that the calculated map explains well the chemical shift behavior of the a-helix and p-sheet forms in poly(L-Ala) and some proteins. This suggests that the calculated map is applicable to the structural analysis of proteins with complicated structure. 

Fluorine-19 NMR spectroscopy has had widespread use in the structural analysis of polymers. This is because the presence of a fluorine in a monomer leads to a polymer where the fluorine may be in a range of environments, leading to a range of peaks which are not obscured by other resonances from elsewhere in the molecule as they are for proton and carbon NMR. Figure 5 shows the fluorine-19 spectrum of poly(tetrafluoroethene), 11. Each carbon in the chain can have the R or S configuration with respect to each end of the chain, such that pairs of adjacent centres can be meso, m, or racemic, r. Depending upon the configuration of the two carbons to either side of the fluorine, different resonances are... 

After completion of the calculations182 on poly(Gly-Pro-Pro), it was learned that Okuyama et al.187 had carried out a single-crystal X-ray structure analysis of (Pro—Pro—Gly)10. The calculated structure (Figure 25) is in agreement with theirs, with a root-mean-square deviation of 0.3 A for all (nonhydrogen) atoms, based on a comparison between the X-ray coordinates (kindly provided by Professor M. Kakudo) and the computed coordinates. 

The reactions of alkynes or alkenes with Ni-R bonds are important in organic synthesis, particularly when they involve metallacyclic precursors because these reactions lead to synthetically valuable poly- or heterocyclic derivatives. A crucial question in this context is the regioselectivity of the insertion reaction. To address this issue, a systematic study has been carried out on the insertion of various unsymmetrical alkynes into the Ni-C(sp ) bond of the nickellacycle (8) (Scheme 14) structural analysis of the fairly stable 7-membered ring Ni-aUcenyl products (9) indicates that the insertions are primarily governed by electronic factors. ... 

Products 82 are of low chemical stability and rapidly decompose (several minutes) in air decomposition is slower (several days) in the absence of water and oxygen. Thus, these investigations have defined general limitations for poly(arylenemethide) synthesis, set by their chemical instability. A structural analysis of a decomposed ladder-type poly(arylenemethide) 76 has clearly shown that the bridge (methide position) is the site of attack with formation of hydroxyl- or hydroperoxyl-groups [102]. 

Results for a Py-GC/MS analysis of poly(l-hexene-sulfone) CAS 34903-07-6 with the idealized structure [-CH(C4H9)-CH2-S02-CH2-CH(C4H9)-S02- ] are shown in Figure 12.2.1. The pyroiysis was done in similar conditions as for other examples, at 600° C in... 

Six spin-coupling pathways are subtended by typical glycosidic linkages, and in the structural analysis of oligo- and poly-saccharides, it would clearly be advantageous to use as many of these coupling constants as possible for the definition of molecular geometry, particularly in view of the limited number of NOEs observed in these systems. 

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