Fourier transform infrared spectroscopy copolymers

Ethylene-styrene copolymer Ethylene-vinyl acetate copolymer Ethylene-vinylchloride copolymer Fourier transform infrared spectroscopy Gas chromatography High-density polyethylene Hydroperoxide decomposition Isobutylene... 

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. 

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... 

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. 

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. 

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. 

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... 

On simple, one- or two-layer structures, identification of the polymer type is conveniently achieved using Fourier transform infrared spectroscopy (FTIR). Each of the major polymer classes or copolymers has unique infrared spectra and are easily identified by comparison of the spectra to reference spectra. 

The basic characteristics of these segmented copolymers were studied using several techniques. These techniques included fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), intrinsic viscosity (IV), and differential scanning calorimetry (DSC). 

Odeberg and co-workers [13] demonstrated grafting reactions in polystyrene-poly(n-butylacrylate) copolymers using Fourier transform infrared spectroscopy and proton neutron magnetic resonance spectroscopy. DMA and TMA are used to study crosslinking. 

Paxton and Randall [13] used Fourier transform infrared spectroscopy (FT-IR) to measure the concentration of bound ethylene in ethylene propylene copolymers in amounts down to 0.1 %. These polymers contained >95% propylene, with the ethylene units present as isolated entitles between two head-to-tail propylene units. These workers point out that most IR bands used for determining copolymer compositions are sensitive to sequences of both monomers. This IR method for compositional analysis can be calibrated if (a) known standards of similar constitution to the copolymers being analysed are available and (b) assignments and behaviour of the calibration bands are well established preferably the absorptivities of these bands should be relatively independent of the position of monomer units in the chain. Thus, quantitative IR analysis of copolymers depends primarily on the standards employed whose composition can be determined directly and reliably. Paxson and Randall [13] used C-NMR to provide such reference standards for the less time-consuming IR measurements because it is relatively inexpensive and easy to operate for copolymer analysis. They showed that an excellent correlation is obtained between C-NMR and IR results on a series of ethylene-propylene copolymers containing >95% wt% propylene. 

Heischer et al. [172] measured the interfacial tension reductirai credited to the complexation between carboxy-terminated PBD and amine-terminated PDMS, which were added to an immiscible blend of PBD and PDMS. The changes in interfacial tensimi resembled the behavior observed for block copolymer addition to homopolymer blends there is initially a linear decrease in interfacial tension with the concentration of functional homopolymer up to a critical concentration, at which the interfacial tension becomes invariant to further increases in the concentration of functional material. However, the formation of interpolymer complexes depends on the equilibrium between associated and dissociated functional groups and, thus, the ultimate plateau value for interfacial tension reduction is dependent on the functional group stoichiometry. A reaction model for end-complexation was developed in order to reproduce the interfacial tension reduction data with Fourier transform infrared spectroscopy applied to determine the appropriate rate constants. The model provided a reasonable qualitative description of the interfacial tension results, but was not able to quantitatively predict the critical compositions observed experimentally. 

Various methods have been applied to the determination of chloroprene - maleic anhydride [137], maleic anhydride polypropylene [138] by Fourier transform infrared spectroscopy and NMR [139] and maleic anhydride - styrene - methyl methacrylate, maleic anhydride - styrene - vinyl acetate and maleic anhydride - S-allyl propionate copolymers by FTIR spectroscopy [140]. 

Frequently, in work carried out to attempt to elucidate the microstructure of polymers and copolymers, it is found necessary to employ not one physical analytical technique, but a range of such techniques. The literature abounds in examples of this need. Judging by the number of papers published, three of the most useful and commonly used techniques are combinations of Fourier transform infrared spectroscopy (FTIR) or infrared (IR) spectroscopy and matrix assisted laser desorption-ionisation time-of-flight (MALDI-TOF) mass spectrometry with nuclear magnetic resonance spectroscopy or photon magnetic resonance spectroscopy. 

Scanning electrochemical microscopy (SECM) has been applied to polymethylmethacrylate, polystyrene and polyethylene glycol. Surface enhanced infrared reflection microscopy was applied to polyacrylonitrile, polybutadiene and styrene resins whilst Fourier transform infrared spectroscopy was applied to polyimides. Finally, nuclear magnetic resonance spectroscopy has been applied to the examination of the surfaces of films of polyethylene, Suryln and ethylene-vinyl acetate copolymer. ... 

Block copolymerization of PCL and PPEs can be performed with the initiation of Al(0 Pr)3. In a typical example, the polymerization of s-CL was initiated by A3 in THF, followed by the addition of phosphoester monomer (eqn [3]). The actual formation of the expected block copolymers was confirmed by nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FT-IR), and gel permeation chromatography (GPC). Kinetic studies revealed that the of PPE follows a linear relationship with monomer conversion (up to 94.3%), and the molecular weight distribution remains narrow with dispersity (PDI) around 1.2, indicating that a limited amount of inter- or intramolecular transesterification reactions occurred. This enables the synthesis of block copolymers with narrow molecular weight distribution, controlled molecular weights, and adjustable compositions. 

Jia and co-workers [11] characterised a solid phase graft copolymer of polypropylene with styrene and maleic anhydride. The graft copolymer was evaluated by Fourier-transform infrared spectroscopy (FT-IR) [12] and Py-GG-MS. 

Un-OH can also be copolymetized with propene on a MAO-pretreated glass surface by Et(Ind)2ZrCl2. Parts of the resulting copolymer are chemically bonded to the surface, as shown by extraction experiments, scanning electron microscopy (SEM) microscopy as well as Fourier transformation infrared spectroscopy (FUR) analysis. Similar results were reported for the copolymerization of ethene with Un-OH by the same catalyst system on the organically modified silicate montmorillonite (OMMT) resulting in PE-Un-OH/OMMT nanocomposites which consist of well-exfoliated OMMT dispersions and controlled degrees of PE functionalization. ... 

QUANTIFYING SHORT CHAIN BRANCHING MICROSTRUCTURES IN ETHYLENE 1-OLEFIN COPOLYMERS USING SIZE EXCLUSION CHROMATOGRAPHY AND FOURIER TRANSFORM INFRARED SPECTROSCOPY (SEC-FTIR)... 

Multiple block copolymers form a domain-matrix morphology due to the chemical and steric incompatibilities of the two chemically different blocks. The surface molecular and morphological structures of a series of block copolyether-urethane-ureas have been studied in detail via Electron Spectroscopy for Chemical Analysis (ESCA) and Fourier Transform Infrared Spectroscopy (FTIR) coupled with internal reflectance techniques. ESCA provides elemental information concerning the very surface, while FTIR provides the molecular and secondary bonding Information of the surface and into the bulk. Bulk and surface chemical and morphological structures are shown to be quite different, and are affected by synthetic and fabrication variables. 

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