Amorphous polymers high-performance

Properties of various amorphous polymers appear in Tables 1.4 and 1.5. For comparison, the properties of two commodity amorphous polymers, high-impact polystyrene (HIPS) and acrylonitrile/butadiene/ styrene (ABS), are included in Table 1.4. Since HIPS and ABS are multicomponent resins, their average property values are shown. Properties of the highly aromatic high-performance amorphous polymers... 

Polyether Imides. Polyether imides (PEIs) are amorphous, high performance thermoplastic polymers that have been in use since 1982. The first commercial polyether imides were the Ultem series developed by the General Electric Co. The first, Ultem 1000 [61128-24-3] is prepared from phthahc anhydride, bisphenol A, and meta-phenylenediamine and has the following stmcture ... 

The use of femtosecond pulses in nonlinear optics has one obvious advantage high peak power, necessary to observe the nonlinear effect, can be obtained from low total power in the pulse. This made samples with a low damage threshold amenable for HRS measurements. One example of such sample is amorphous polymer films. These films do not have the optical quality of single crystals. They are more susceptible to optical damage. With the femtosecond pulses, we have been able to perform HRS measurements on solid thin films, to study the orientational correlation between nonlinear optical chromophores in the film.10 13... 

Wilkinson, S. P., et al., Reactive Blends of Amorphous Functionalized Engineering Thermoplastics and Bismaleimide/Diallyl Bisphenol A Resins for High Performance Composite Matrices, Polymer Preprints, vol. 33, no. 1, 1992, p. 425. 

Another possible evidence of grafted organic/polymeric molecules onto CNT surface can be achieved by microscopy analyses using both principal types of electron microscopy - transition electron microscopy, TEM, or scanning electron microscopy, SEM (15,19,24,44,45,47). Such analyses are usually performed after careful extraction of the polymer from tubes by polymer solvents, performed several times by a reflux procedure with an excess of solvent therefore it is supposed that only covalently attached molecules remain fixed at CNT surface. High Resolution mode of TEM analysis shows the evidence of amorphous material on nanotubes surface (15). 

Supercritical or high pressure carbon dioxide can induce polymer crystallization and plasticize polymers. The systematic study on the interaction of carbon dioxide with twenty different crystalline and amorphous polymers has been performed and various influencing parameters have been determined. Through the examination, analysis and comparison of the yield strength, ultimate elongation and modulus both before and after treatments in supercritical carbon dioxide at 3000 psi and 70°C, it was found that two main factors, i.e., degree of crystallinity and the presence of a polar side chain group, e g., ester. 

At sufficiently high pressure, the absorption of certain gases can result in substantial swelling of the polymer this can be beneficial or deleterious. The solubility of gases in amorphous polymers is important in a variety of membrane and polymer technologies. In membrane technology, it has been shown that membrane performance is dependent on the solubility of the... 

The last few years have witnessed a high level of activity pertaining to the research and development of all-solid, thin-film polymer electrolyte batteries most of these use lithium as the active anode material, polymer-based matrices as solid electrolytes, and insertion compounds as active cathode materials. High-performance prototypes of such batteries stand currently under research, whose trends are expected to include the development of amorphous polymers with very low glass-transition temperatures, mixed polymer electrolytes, and fast-ion conductors in which the cationic transport number approaches unity. 

Organic field effect transistor (OFET) devices have been fabricated from pBTTT polymer solutions and hole mobility values of up to 0.8cm /V s were reported in a nitrogen atmosphere. These values approach that of high performing evaporated small molecule devices and are comparable to amorphous silicon. In bottom gate, bottom-contact devices, in which the active semiconductor layer is the exposed top surface, the effect of different ambient conditions has been evaluated. Exposure to unpurified, ambient air in which the humidity is -50%, results in an initial increase in the off-current of the device. In filtered, low humidity air, transistor devices remain very stable over time. 

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