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Microstructural details of poly(phenyl glycidyl ether) (PPGE) and its optically active form obtained by the aluminium isopropoxide (AIP)/ZnCl 2 ionic-coordinative initiator were analysed by nuclear magnetic resonance techniques. In order to assign the soluble fraction signals unmistakably, PPGE samples had to be synthesized using various cationic initiator systems. Several modifications...
Micromorphological and microstructural characterizations of the type and degree of crystallinity and the relative dispersion of phases within polymers, as well as in the study of their surfaces and associated interfaces, offer a number of challenges in the field of materials science of polymers. Microscopy is a natural methodology for the acquisition of microstructural information, but for polymers...
The microstructures of phenyl and 4-fluorophenyl polyacrylates were studied by 500 MHz 1 H and 125 MHz 13 C n.m.r. spectroscopy. The isotacticity parameters of both polyacrylates were calculated from the 1 H n.m.r. spectra, giving the values P m = 0.44 for poly(phenyl acrylate) and P m = 0.48 for poly(4-fluorophenyl acrylate). The 13 C n...
The 13 C nuclear magnetic resonance (n.m.r.) spectra were found to provide a means for direct observation of the structures formed along the glycolide/lactide copolymer chain upon transesterification. Nevertheless 1 H n.m.r. spectroscopy appeared to be more convenient and useful in the analysis of chain microstructure. The glycolide methylene group region of the proton spectra...
The effect of a plastic deformation, induced by a simple shear, on the nanostructure of amorphous polycarbonate (PC), is studied by low-frequency Raman scattering (LFRS). As previously observed for poly(methyl methacrylate) (PMMA), an excess appears in the low-frequency part of LFRS spectra after plastic deformation. The excess is stronger in the case of PC than in the case of PMMA, and its light...
Polymer electrolytes based on triblock copolymers of ethylene oxide (EO)/propylene oxide (PO)/ethylene oxide of moderate molecular weight and narrow block-length distributions, doped with M(CF 3 SO 3 ) 2 and M[N(CF 3 SO 2 ) 2 ] 2 (M = Mg, Ca, Sr and Ba), LiCF 3 SO 3 and LiN(CF 3 SO 2 ) 2 have been investigated...
The lamellar morphology of melt-crystallized thin film spherulites of isotactic and syndiotactic polypropylene (iPP and sPP) has been investigated by transmission electron microscopy (TEM) in phase contrast conditions. It is found that the arrangement and orientation of the lamellae depend on the crystallization temperature. The spherulitic crystallization of iPP has changed from dominant radial to...
We demonstrate that annealing conductive, solvent-case poly(3-hexylthiophene) (P3HT) films under reduced vacuum improved their structural properties and induced higher conductivity. These preliminary results suggest that thermal processing of conductive polymers may be a useful step in their future device fabrication.
A method for characterizing triad and pentad distribution by 13C n.m.r. spectroscopy has been developed and applied for an acrylate-methacrylate copolymer for which the chemical shifts of the homopolymers were sufficiently separated to observe mixed sequences up to pentads. Calculation of the intensity was performed applying Markov-Bernoulli statistics while the chemical shift for each sequence was...
Methods of microscopic observation and macroscopic characterization have been developed for determining the co-phase continuity in immiscible binary blends. After selective dissolution of the component polymers, the morphologies of microscopic observation are consistent with the results of macroscopic observation and weight percentage determination. By using these methods, the relationship between...
The microstructure and microphase behaviour of diblock (M a ≈ 27 and 50 kg mol −1 ) and triblock (M a ≈ 50kg mol −1 ) copolymers of polystyrene (PS) and poly(ethylene-alt-propylene) (PEP) were studied by small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and dynamic mechanical thermal analysis (DMTA). The composition was varied from 10 wt.%...
The microstructure of poly(trans-4-acryloyloxyazobenzene) P(AB) homopolymer, prepared by solution polymerization using AlBN as initiator is analysed by one- and two-dimensional NMR spectrotcopy. Sequence distribution was calculated from 13 C{ 1 H}n.m.r. spectrum of the homopolymer. A 13 C distortionless enhancement by polarization transfer spectrum was used to differentiate...
trans-4-Acryloyloxyazobenzene/methyl methacrylate (A/M) copolymers were prepared by free-radical solution polymerization in DMF using AIBN as initiator. The copolymer compositions were obtained from 1 H n.m.r. spectroscopy. The reactivity ratios for the copolymerization of A with M were calculated using the Kelen-Tudos (KT) and non-linear error in variables model (EVM) methods. The reactivity...
Previous work has shown that dragline silk of Nephila madagascariensis is not homogeneous in cross-section. We report here that the core of Nephila edulis silk also contains extremely fine elongated, electron lucent domains. These domains may contribute to the exceptional tensile strength and toughness of this material by acting as stress concentration parts or (and) fluid-filled canaliculi.
The synthetic process of hyperbranched aliphatic polyesters based on 2,2-bis(hydroxymethyl)propionic acid (AB 2 -type monomer) and 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (B 3 -type core) was investigated with in situ Fourier transform infrared (FT-IR) spectroscopic analysis. The experimental parameter was the stoichiometric ratio between monomer and core moiety corresponding to...
The process of electrostatic fiber formation, or electrospinning, was used to create biocompatible thin films for use in implantable devices. The morphology of the thin films was found to depend on process parameters including solution concentration, applied electric field strength, deposition distance, and deposition time. The microstructure of the coatings was examined by Transmission Electron Microscopy...
Blends of conjugated polymers with ultrahigh molecular weight polyethylene (UHMW-PE) containing up to 30% (w/w) of poly(2-butyl, 5-(2'-ethyl-hexyl)-1,4-phenylene vinylene) (BuEH-PPV) have been prepared by gel processing. The microstructure of both pristine and oriented (tensile drawn) films were studied using optical microscopy (365nm ultraviolet illumination), X-ray diffraction and transmission electron...
Polycarbonate(PC)/ poly(styrene-co-acrylonitrile)(PSAN) blends were investigated by Raman and confocal Raman imaging spectroscopy, revealing the existence of two-phase (PC-rich and PSAN-rich) microdomain structure. This structure is coarser in blends with comparable component contents. During cold drawing the microdomains are strongly extended. As follows from polarised photoacoustic FTIR spectroscopy,...
Copolymers of cationic trimethyl(4-methacrylamidophenyl)ammonium methyl sulfate (TMMAPhAMS) or zwitterionic 3-dimethyl(4-methacrylamidophenyl)ammonato propane sulfonate (DMMAPhAPS) monomer with methacrylamide (MAA) have been prepared by free radical polymerization using 4,4′-azobis-cyanovaleric acid as an initiator in aqueous solution. Copolymer compositions were obtained by elemental analysis. The...
A new kinetic gelation model that incorporates the kinetics of non-linear free radical copolymerization is presented. Copolymerization of bi- and tetrafunctional monomer mixtures is simulated to characterize kinetic effects on polymerization statistics and microstructures. An algorithm for random next step selection in a self-avoiding random walk and efficient mechanisms of component's mobility are...
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