Polymer blends FTIR spectroscopy

Keywords Focal Plane Array FTIR Imaging Infrared spectroscopy Polymer blends... 

Transition metal coordination of Cu(II) carboxylate groups and pyridine groups was employed as a means of coupling a telechelic butadiene-base polymer with a randomly functionalized styrenic polymer. Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) indicated partial miscibility of the two polymers and Fourier transform infrared (FTIR) spectroscopy demonstrated that interactions occurred on a molecular level. When compared with blends of PSVP and the free acid derivative of CTB, the compositions based on the transition metal complex had improved dimensional stability at elevated temperatures, though there remains some question as to the stability of the copper salt to hydrolysis. Electron spin resonance (ESR) spectroscopy showed that only the... 

For the studies of interactions in polymer blends the nuclear magnetic resonance (NMR), and Fourier transform infrared spectroscopy (FTIR) are of principal significance. 

Torikai et al. [1994] compared the effects of gamma irradiation of films of PS/PMMA blends and PS-PMMA copolymer (co-PS-PMMA) (Table 11.9). Polymer films were cast from methylene chloride solutions and were dried under vacuum. Based on the UV and FTIR spectroscopy, and viscosity measurements, Torikai et al. [1994] concluded that whereas the presence of PS in the copolymer provided protection against radiation-induced degradation to the PMMA units, similar... 

Fourier transform infrared (FT-IR) spectroscopy can be used to characterize drug substances, polymer blends, polymer complexes, dynamics, surfaces, and interfaces, as well as chromatographic effluents and degradation products. It provides information about the complexation and interactions between the various constituents in the PECs. It is capable of qualitative identification of the structure of unknown materials as well as the quantitative measurement of the components in a complex mixture. FT-IR spectra of physical mixture and PEC can be determined by FT-IR spectrophotometer using KBr disc method in the range of 4000 to 250 cm h Since the stability and drug substance is very important in several applications, determination of their physicochemical stability is crucial. The FTIR spectra of polyacrylic acid, PVP, metformin hydrochloride, and PEC microparticles of metformin were shown in Figure 56.8. The FTIR spectra of polyacrylic acid and PVP have shown... 

During the past three years or so, chain connectivity and its effect on the free energy of mixing and phase behaviour of (co)polymer blends has been studied. IR spectroscopy has been the primary tool because in carefully chosen mixtures it is possible to measure the fraction of hydrogen bonded groups present as a function of composition and temperature. Attention is now turned to the effect of crosslinking one or both of the (co)polymers in the blend and the results of recent FTIR spectroscopic studies are presented. 

Specific interactions in binary blends of ethylene-vinyl acetate copolymer with various low molecular weight terpene-phenol tackifying resins (TPR) were systematically investigated, as a function of the composition of the blend and of the electron acceptor ability of the resin, by using attenuated total reflection FTIR spectroscopy. Molecular acid-base were evidenced between TPR hydroxyl groups and EVA carbonyl groups. Quantitative information on the fraction of acid-base bonded entities, the enthalpy and equilibrium constant of pair formation were obtained. A crystalline transition of the EVA copolymer was observed and discussed in terms of enthalpy and entropy considerations based on FTIR and calorimetric DSC investigations. Fundamental results are then summarised to predict the interfacial reactivity of such polymer blends towards acid or basic substrates. 16 refs. 

Journal of Polymer Science Polymer Physics Edition 31, No. 12, Nov. 1993, p.l769-77 DYNAMIC RHEO-OPTICAL CHARACTERISATION OF A LOW DENSITY POLYETHYLENE/PERDEUTERATED HIGH DENSITY POLYETHYLENE BLEND BY TWO DIMENSIONAL STEP-SCAN FTIR SPECTROSCOPY... 

This section introduces a novel application of IR spectroscopy, namely IR imaging, and the specific sampling technique of attenuated total reflectance (ATR). FTIR imaging in ATR mode allows one to visualize the spatial distribution of different components in polymeric materials and to study directly the effect of high-pressure CO2 on this distribution. This novel approach should benefit polymer scientists studying polymer blends and their processing with SCCO2. 

The use of infrared spectroscopy for the characterization of polymer blends is extensive (Olabisi et al. 1979 Coleman and Painter 1984 Utracki 1989 He et al. 2004 and references therein Coleman et al. 1991, 2006). The applicability, fundamental aspects, as well as principles of experimentation using infrared dispersive double-beam spectrophotometer (IR) or computerized Fourier transform interferometers (FTIR) were well described (e.g., Klopffer 1984). 

Most utility polymeric articles available today contain multiphase polymeric systems comprised of semi-crystalline polymers, copolymers, polymers in solution with low molar mass compounds, physical laminates or blends. The primary aim of using multicomponent systems is to mould the properties available from a single polymer to another set of desirable material properties. The property development process is complex and depends not only on the properties of the polymer(s) and other components but also on the formation process of the system which determines the developed microstmcture, and component interaction after formation. Moreover, the process of polymer composite formation and the stability of the composite is a function of environmental parameters, e.g., temperature, presence of other species etc. The chemical composition and some insight into the microscopic structure of constituents in a polymer composite can be directly obtained using Infrared (IR) spectroscopy. In addition, a variety of instrumental and sampling configurations for spectroscopic measurements combine to make irrfra-red spectroscopy a versatile characterization technique for the analysis of the formation processes of polymeric systems, their local structure and/or dynamics to relate to property development under different environmental conditions. In particular, Fourier transform infrared (FTIR) spectroscopy is a well-established technique to characterize polymers [1, 2]. 

Fourier transform infrared (FTIR) studies of the poly(bis-phenol A-carbonate) (PC) - poly(e-caprolactone) (PCL) blend system are presented. This is a complex blend system containing two crystallizable polymers, with large differences in crystalline melting points and glass transition temperatures (Tg), which are compatible in the amorphous state. FTIR spectroscopy has proven to be an excellent technique with which to study these blends. Evidence for the presence of specific chemical interactions between the two polymers in the amorphous state, which infers compatibility, has been obtained. Furthermore, the crystallization of the components of this blend system are readily followed at room and elevated temperatures. Solvent and polymer induced crystallization and the role of the effective Tg of the amorphous phase of the blends in the crystallization of PC is discussed. 

FTIR spectroscopy has proven to be an excellent technique with which to study the complex multiphased PC/PCL blend system. Spectral evidence has been obtained which suggests the presence of chemical interactions between the polymeric components in the amorphous state. These results are analogous to those previously reported for the PCL/PVC blend system and imply a compatible amorphous phase. Additionally, we have interpreted infrared spectra of the blends acquired at room and elevated temperatures in terms of amorphous and preferred ( crystalline ) conformations of the components. Effects of solvent and polymer induced crystallization of PC are readily observed. 

Coleman and Painter [4-6] consider hydrogen bonding as the central strong interaction in polymers that cause the observed phase behavior and miscibility. They have used Fourier transform infrared (FTIR) spectroscopy to study the hydrogen bonding in polymer blends in systems such as polyamides and polyurethanes. A large class... 

UV-vis, FTIR, NMR, Raman spectroscopy and ESR are the most powerful ways of analysing polymer blends based on NR and its derivatives. For example, NMR provides unique and important molecular motional and interaction profiles containing pivotal information on NR blend function. Some of the applications of spectroscopy are listed below ... 

Solution structure the only technique for atomic-resolution structure of polymer blend based on NR in organic solutions confirmed by UV-vis spectroscopy, FTIR and NMR. 

There are specific structural and spatial problems in whieh Raman spectroscopy plays a dominant and important role based on higher sensitivity (due to resonance enhancement) and higher spatial resolution than FTIR. Specifically, micro-Raman spectroscopy has been applied in the analysis of (glass) fibres and their surface treatments, fibre composites, multilayer plastic films, foils and coatings, polymer blends, interfaces in eomposites, contaminant and paints/pigments [488]. 

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