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Host Polymer (host + polymer)
Selected AbstractsEffect of surface modifying macromolecules stoichiometric ratio on composite hydrophobic/hydrophilic membranes characteristics and performance in direct contact membrane distillationAICHE JOURNAL, Issue 12 2009M. Qtaishat Abstract The stoichiometric ratio for the synthesis components of hydrophobic new surface modifying macromolecules (nSMM) was altered systematically to produce three different types of nSMMs, which are called hereafter nSMM1, nSMM2, and nSMM3. The newly synthesized SMMs were characterized for fluorine content, average molecular weight, and glass transition temperature. The results showed that fluorine content decreased with increasing the ratio of ,,,-aminopropyl poly(dimethyl siloxane) to 4,4,-methylene bis(phenyl isocyanate). The synthesized nSMMs were blended into hydrophilic polyetherimide (PEI) host polymer to form porous hydrophobic/hydrophilic composite membranes by the phase inversion method. The prepared membranes were characterized by the contact angle measurement, X-ray photoelectron spectroscopy, gas permeation test, measurement of liquid entry pressure of water, and scanning electron microscopy. Finally, these membranes were tested for desalination by direct contact membrane distillation and the results were compared with those of commercial polytetraflouroethylene membrane. The effects of the nSMM type on the membrane morphology were identified, which enabled us to link the membrane morphology to the membrane performance. It was found that the nSMM2/PEI membrane yielded the best performance among the tested membranes. In particular, it should be emphasized that the above membrane was superior to the commercial one. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Dendronized tricyanopyrroline-based chromophores in nonlinear optical active host polymerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2008Mai Ha Hoang Abstract We synthesized new nonlinear optical (NLO) chromophores containing a 3,5-bis(3,5-bisbenzyloxy-benzyloxy)-benzoate dendron. Tricyanopyrroline (TCP)-based chromophores were designed and prepared by virtue of its strong electron withdrawing property. A soluble polyimide containing 6-({4-[2-(1-allyl-4-cyano-5-dicyanomethylene-2-oxo-2,5-dihydro- 1H -pyrrol-3-yl)-vinyl]-phenyl}-butyl-amino)-hexanoyl group in the side chain was also prepared as an NLO active host polymer. A benzoate dendron was tethered at two different binding positions of the chromophore to yield two different guest molecules. Thin-film composites of these dendronized chromophores dissolved in the NLO active polyimide host were employed to fabricate the electro-optic (EO) samples. The EO properties of new NLO polyimides containing dendronized chromophores were compared with those of the sample with nondendronized plain chromophores. The effect of a bulky dendron on the EO properties was investigated using an in situ reflection technique. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5064,5076, 2008 [source] Immiscible polymers in double spin-coated electroluminescent devices containing phenyl-substituted tris(8-hydroxyquinoline)aluminum derivatives soluble in a host polymerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 19 2003E. Shoji Abstract Three new phenyl-substituted tris(8-hydroxyquinoline)aluminum (AlQ3) derivatives have been synthesized: tris(5-phenyl-8-quinolinolate-N1,O8)aluminum, tris(5,7-diphenyl-8-quinolinolate-N1,O8)aluminum, and tris[5,7-bis(p -fluorophenyl)-8-quinolinolate-N1,O8]aluminum. These AlQ3 derivatives are easily soluble in common organic solvents and form solid-phase solutions in a poly(aryl ether ketone) host polymer (A435). These interesting properties allow the use of soluble AlQ3 derivatives in double spin-coated organic light-emitting devices of the type ITO/NPB-QP/A435 + 50 wt % soluble AlQ3 derivative/Mg, where NPB-QP is a hole-transporting polymer insoluble in toluene, the solvent for A435. Typical double spin-coated organic layer devices are characterized by an emission at 530,539 nm, a threshold voltage of 6,9 V, and a maximum luminance of 1800,4000 cd/m2 at 21,25 V. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3006,3016, 2003 [source] Fabrication of Patterned Polydiacetylene Composite Films Using a Replica-Molding (REM) TechniqueMACROMOLECULAR RAPID COMMUNICATIONS, Issue 3 2010Oktay Yarimaga Abstract Functional three-dimensional (3D) micropatterns of diacetylene supramolecules embedded in a host polymer have been successfully fabricated by a replica-molding (REM) technique. Dimensional reduction as a result of liquid evaporation during the curing process does not affect the conformational features of the transferred patterns. Polymerization of the diacetylene vesicles using 254,nm UV-light irradiation from the back-side of the transparent substrate induces blue colored polydiacetylene (PDA) micro-images. Interestingly, the polymerization selectively occurs in the molded areas because of the sub-300,nm light blocking property of SU-8. 3D fluorescence patterns are readily obtained by heat treatment of the blue images on the film. [source] Terahertz Photonic Crystals Based on Barium Titanate/Polymer Nanocomposites,ADVANCED MATERIALS, Issue 19 2008Joseph Lott Polymeric materials with engineered refractive indices for applications in the THz regime can be fabricated and processed by conventional melt-processing of inorganic nanomaterials and conventional host polymers. The approach opens up new opportunities for the creation of optical elements to manipulate the technologically relevant THz radiation, for example photonic crystals. [source] Studies on nylon-6/EVOH/clay ternary compositesPOLYMER COMPOSITES, Issue 1 2006N. Artzi Nylon-6 (Ny-6)/EVOH blends are interesting host multiphase systems for incorporation of low clay contents. The Ny-6/EVOH blend is a unique system, which tends to chemically react during melt-mixing, affecting thermal, morphological and mechanical properties of the ternary systems containing clay. The addition of clay seems to interrupt the chemical reaction between the host polymers at certain compositions, leading to lower blending torque levels when clay is added. A competition between Ny-6 and EVOH regarding the intercalation process takes place. Ny-6 seems to lead to exfoliated structure, whereas EVOH forms intercalated structure, as revealed from XRD and TEM analyses, owing to thermodynamic considerations and preferential localization of the clay in Ny-6. Hence, the ternary systems have combined intercalated and delaminated morphology or complete exfoliated morphology depending on blend composition and clay content. Selective extraction experiments (gel content) indicate the formation of chemical reaction between the Ny-6 and EVOH, and give an indirect indication of the polymer content residing in the galleries. The thermal properties of the polymers were found to be affected by the occurrence of chemical reaction, the level of intercalation and exfoliation and plasticizing effect of the low molecular weight onium ions treating the clay. Of special interest is the increased storage modulus attained upon the addition of only 1.5 wt% clay. POLYM. COMPOS. 27:15,23, 2006. © 2005 Society of Plastics Engineers [source] | ||||||||||