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Fourier transform infrared copolymers

NMR) [24], and Fourier transform-infrared (FT-IR) spectroscopy [25] are commonly applied methods. Analysis using mass spectrometric (MS) techniques has been achieved with gas chromatography-mass spectrometry (GC-MS), with chemical ionisation (Cl) often more informative than conventional electron impact (El) ionisation [26]. For the qualitative and quantitative characterisation of silicone polyether copolymers in particular, SEC, NMR, and FT-IR have also been demonstrated as useful and informative methods [22] and the application of high-temperature GC and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) is also described [5]. [Pg.239]

Principal Component Regression (PCR) was used by Tuchbreiter and MueUiaupt to determine the composition of a number of random ethane/propene, ethane/1-hexene, and ethane/l-octene copolymers [120]. After polymerization, the polymers were characterized by both Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FT-IR) and C NMR and multivariate calibration models using PCR were subsequently developed to estimate the co-monomer content. [Pg.132]

Tuchbreiter A, Marquardt J, Zimmermann J et al. (2001) High-throughput evaluation of olefin copolymer composition by means of attenuated total reflection fourier transform infrared spectroscopy. J Comb Chem 3 598-603... [Pg.147]

Coleman, M. M., Sivy, G. T. Fourier Transform Infrared Studies of the Degration of Polyacrylonitrile) Copolymers I. Introduction and Comparative Rates of the Degradation of Three Copolymers Below 200 °C and Under Reduced Pressure. Preprint submitted to CARBON... [Pg.152]

Regarding the spatial aspects of the enzymatic degradation of CA-g-PLLA, a surface characterization [30] was carried out for melt-molded films by atomic force microscopy (AFM) and attenuated total-reflection Fourier-transform infrared spectroscopy (ATR-FTIR) before and after the hydrolysis test with proteinase K. As exemplified in Fig. 3 for a copolymer of MS = 22, the AFM study showed that hydrolysis for a few weeks caused a transformation of the original smooth surface of the test specimen (Fig. 3a) into a more undulated surface with a number of protuberances of 50-300 nm in height and less than a few micrometers in width (Fig. 3b). The ATR-FTIR measurements proved a selective release of lactyl units in the surface region of the hydrolyzed films, and the absorption intensity data monitored as a function of time was explicable in accordance with the AFM result. [Pg.106]

Carboxylate ionomers have been characterised with Fourier transform-infrared (FT-IR) in the region of antisymmetric stretching vibration of carboxylate anions. Figure 4.8 shows carboxylate ionomer [89] of ethylene methacrylic (4%) copolymer). [Pg.147]

Acetonitrile was also used as the solvent for the first successful synthesis of a PAn/PPy copolymer via galvanostatic (constant-current) electropolymerization of mixtures of aniline (0.5 M) and pyrrole (0.1-1.0 M) in acetonitrile solvent in the presence of CF3COOH as acid and tetraethylammonium tetrafluoroborate as supporting electrolyte. Differential scanning calorimetry and Fourier transform infrared (FTIR) measurements confirmed that the electrically conducting product was a mixture of PAn, PPy, and a random PAn/PPy copolymer.36... [Pg.141]

By sequential copolymerization of styrene and propylene using a modified Ziegler-Natta catalyst, MgCl2/TiCl4/NdClc(OR) //Al(iBu)3, which was developed in our laboratory, a styrene-propylene block copolymer is obtained. After fractionation by successive solvent extraction with suitable solvents, the copolymer was subjected to extensive molecular and morphological characterization using 13C-NMR, DSC, DMTA, and TEM. The results indicate that the copolymer is a crystalline diblock copolymer of iPS and iPP (iPS-fo-iPP). The diblock copolymer contains 40% iPS as determined by Fourier transform infrared spectroscopy and elemental analysis. [Pg.371]

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. [Pg.295]

Copolymers with sites for association in aqueous solutions were pre-pared by copolymerizing acrylamide with N-alkylacrylamides or with the ampholytic monomer pairs sodium 2-acrylamido 2 methylpro-panesulfonate (NaAMPS) and 2-acrylamido-2-methylpropane-dimethylammonium chloride (AMPDAC). The copolymers were characterized by elemental analysis, NMR and Fourier transform infrared spectroscopy, and lowhangle laser and quasielastic lightscattering measurements. Rheological properties were studied as a function of microstructure, molecular weight, polymer concentration, electrolyte concentration, and shear rate. On the basis of those results, a conceptual model that is based on microheterogeneous domain formation in aqueous solutions is proposed. [Pg.437]

Recently, we reported on the compatibUity of PVME with styrene/1- or 2-vinylntphthalene(VN) copolymer using glass transition temperature and Fourier-Transform infrared (FTIR) spectroscopy . The compatibility of the styreneATN derivative copolymers with PVME was found to become weaker as the composition of styrene in the copolymers is decreased. It was also found that the compatibility of the copolymers with PVME is better for 2-VN containing copolymers than for 1-VN containing copolymers . [Pg.551]

Fourier transform infrared (FTIR) and solid-state nuclear magnetic resonance (NMR) spectroscopic analyses both provided positive evidence for hydrogen-bonding interactions within these copolymer systems. We obtained... [Pg.42]

Torikai et aU have y-irradiated poly(styrene-co-methacrylate) copolymers and blends of polystyrene and polymethacrylate. They investigated the influence of irradiation on PMMA by ultraviolet and Fourier transform infrared spectroscopies and by viscosity measurements. In the case of the blends, the degradahon of the PMMA is similar to that awaited. No shielding effect... [Pg.269]

Fourier transform infrared (FTIR) second-derivative spectra of thermoplastic starch and vinyl alcohol copolymer systems with droplet-like structure, in the range of starch ring vibrations between 960 and 920 cm , provide for an absorption peak at about 947 cm (Figure 2.7), as observed for amylose when complexed (V-type complex) by low-molecular-weight molecules such as butanol and fatty acids. [Pg.24]

The simplest self-complementary motif involves two-point donor-acceptor (DA) H-bonding interactions that form cyclic dimers. Carboxylic acids, for example, are ubiquitous and have been investigated for decades. Fourier transform infrared (FTIR) spectroscopy of poly(acrylic acid)s and ethylene-methacrylic acid copolymers show that dimers persist well above the glass transition temperature (Tg) of the materials [12, 13]. Furthermore, carboxylic acids can interact within polymer melts. Instead of forming dimers, they organize into clusters, providing the basis for a supramolecular network. Lillya and colleagues showed that telechelic... [Pg.50]

Bria et al. synthesized a tetracationic cyclophane-aromatic crown ether-type side-chain poly[2]catenane 59 by employing click chemistry, via route iii (Scheme 17.18) [111]. First, the template-directed coupling reaction between bis(bipyridinium) salt 28 and the alkyne-substituted p-xylylene dibromide 55, in the presence of dinaphtho crown ether 54, afforded an alkyne-functionalized [2]catenane 56 [112], Substitution of the chloro group on styrene-vinylbenzyl chloride copolymer 57 (M = 3.7 kDa, M , = 6.3 kDa) with sodium azide gave the azide-functionalized polymer 58 [83,113-115]. By employing CuS04/ascorbic acid as catalyst [116-120], click chemistry between azide-functionaUzed polymer 58 and alkyne-functionalized [2]catenane 56 afforded the side-chain poly[2]catenane 59, the successful formation of which was confirmed with Fourier transform infrared (FTIR) and NMR analyses. Unfortunately, both of these techniques revealed that the reaction of the azide groups was incomplete, and the observation was ascribed to a Coulombic repulsion of the cyclophane units and steric hindrance caused by the bulky catenane units[121]. [Pg.512]


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See also in sourсe #XX -- [ Pg.265 ]




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