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Polymeric Compounds (polymeric + compound)
Selected AbstractsChemInform Abstract: Solvothermal Syntheses and Crystal Structures of the Two New Polymeric Compounds [Ce(C4N3H13)2 (,3 -SbS4)]n and [La(C4N3H13)2 (,4 -Sb2S5) (,3 -SO4)]n.CHEMINFORM, Issue 13 2010Jessica Lichte Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Powder study of poly[(,2 -2,2-dimethylpropane-1,3-diyl diisocyanide)-,2 -iodido-silver(I)]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2009Mwaffak Rukiah In order to explore the chemistry of the bidentate ligand 2,2-dimethylpropane-1,3-diyl diisocyanide and to investigate the effect of counter-ions on the polymeric structure of (2,2-dimethylpropane-1,3-diyl diisocyanide)silver(I) complexes, the title polymeric compound, [AgI(C7H10N2)]n, was synthesized by treatment of 2,2-dimethylpropane-1,3-diyl diisocyanide with AgI. X-ray powder diffraction studies show, as expected, a polymeric structure, similar to the very recently reported Cl, and NO3, analogues [AgX(C7H10N2)]n (X = Cl, or NO3,). In the title structure, the AgI centre is bridged to two adjacent AgI neighbours by bidentate 2,2-dimethylpropane-1,3-diyl diisocyanide ligands via the NC groups to form [Ag{CNCH2C(CH3)2CH2NC}]n chains. The iodide counter-ions crosslink the AgI centres of the chains to form a two-dimensional polymeric {[Ag{CNCH2C(CH3)2CH2NC}]I}n network. This study also shows that this bidentate ligand forms similar polymeric structures on treatment with AgX, regardless of the nature of the counter-ion X,, and also has a strong tendency to form polymeric complexes rather than dimeric or trimeric ones. [source] The effect of polymers and surfactants on the pour point of palm oil methyl estersEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2007Cheah Han Sern Abstract The objective of this research was to find some additives suitable to reduce the pour point (PP) of palm oil methyl esters. The PP properties of palm oil methyl esters (biodiesel) were evaluated with commercially available polymeric and surfactant compounds with various polarities, molecular sizes and structures. The compounds under study were poly(ethylene glycol), poly(methyl methacrylate), poly(ethylene-co-vinyl acetate), poly(styrene-co-maleic anhydride), poly(ethylene glycol) distearate, poly-(octadecyl methacrylate), poly(1-decene), poly(maleic anhydride- alt -1-octadecene), caprylic acid sodium salt, N -lauroylsarcosine sodium salt, polyoxyethylene(2) cetyl ether and polyoxyethylene(10) cetyl ether. Seven out of the twelve polymeric compounds tested were miscible in palm oil methyl esters due to similar polarities of the solute and biodiesel. The blends of the resultant seven polymeric compounds in palm oil methyl esters were evaluated respectively for their effect on the PP property. Poly-(maleic anhydride- alt -1-octadecene) was able to improve the PP of palm oil methyl esters from 12 to 6,°C when 2,wt-% was added. The cloud point was reduced from 12.9 to 8.1,°C, and the cold filter plugging point was reduced from 12 to 7,°C, whilst the flash point value remained unchanged at 156,°C when 2,wt-% of poly(maleic anhydride- alt -1-octadecene) was added to the palm oil methyl esters. [source] Facile Access to an Efficient Solid-Supported Click Catalyst System Based on Poly(ethyleneimine)MACROMOLECULAR RAPID COMMUNICATIONS, Issue 1 2009Lies Bonami Abstract A novel heterogeneous copper(I) catalyst system, which is based on readily available poly(ethyleneimine), has been used as a recyclable catalyst for Cu(I) catalyzed "click" 1,3 dipolar cycloaddition reactions of azides and alkynes in organic media. Branched poly(ethyleneimine) was first methylated and then cross-linked with 1,9-dibromononane. Subsequently, after the immobilization of Cu(I)Br, this system was applied for heterogeneous copper catalyzed click chemistry of a few model reagents and polymeric compounds. [source] High-performance liquid chromatographic separation and identification of polyphenolic compounds from the infusion of Davilla elliptica St. HillPHYTOCHEMICAL ANALYSIS, Issue 1 2008Clenilson M. Rodrigues Abstract The isolation of polyphenolic compounds from an infusion of the Brazilian plant Davilla elliptica (Dilleniaceae), used as tea by virtue of its digestive properties, is described. An improved preparative HPLC method was used in order to isolate pure polyphenols from the complex mixture. Liquid,liquid extraction and solid-phase extraction were employed to minimise the interference of polymeric compounds and to provide an enriched fraction of the compounds of interest. The identification of the isolated compounds was performed using analytical HPLC as well as direct injection electrospray ionisation ion trap tandem mass spectrometry (ESI-IT-MS/MS). The high flavonoid content suggests that D. elliptica may be a promising source of compounds to produce natural phytomedicines. Copyright © 2007 John Wiley & Sons, Ltd. [source] A novel miniature mixing device for polymeric blends and nanocompositesPOLYMER ENGINEERING & SCIENCE, Issue 11 2009Martin Sentmanat A new miniature mixer has been developed to monitor and optimize the preparation protocol of various polymeric compounds and blend systems. The effect of mixing time and other basic processing parameters on the shear and extensional rheological properties of said compounds and blends is examined to understand the effect of undermixed and/or overmixed conditions on the rheological properties and thus the quality of the final products. Results from the new miniature mixer are compared with the results from other conventional mixing techniques to assess the scalability of the new mixing protocol. Two examples are used, those of polymer blending and nanocomposite formation. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers. [source] Frontal polymerization of acrylic monomers for the consolidation of stonePOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 4 2005Silvia Vicini Abstract Polymeric products are largely used for consolidation of stone in the field of cultural heritage. Nevertheless, the main problem of polymeric compounds is related to their macromolecular nature, it being difficult for a polymer to penetrate inside the pores which may have a very small diameter. These considerations are the starting points for in situ polymerization. According to this technique, not the pre-formed polymer, but the monomer is introduced into the stone and it is polymerized in situ in a subsequent step. Frontal polymerization (FP) is a particular technique in which the heat released by the exothermal reaction of monomer to polymer conversion is exploited to promote the formation of a hot traveling front able to propagate and self-sustain the reaction. In the present work, FP is performed inside the pores of the stone and the results lead to the conclusion that the hot front is still active in the presence of an inorganic material which dissipates partially the heat released during the polymerization. In addition some recent applications of FP are discussed in comparison with the traditional polymerization for the in situ consolidation and protection of stones. Copyright © 2005 John Wiley & Sons, Ltd. [source] Two polymeric structures with a benzene-1,2,4,5-tetracarboxylate ligand acting in ,2 - and ,4 -bridging modesACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2009Ana María Atria catena -Poly[[tetraaquabis(1H -pyrazole-,N2)nickel(II)] [[diaquabis(1H -pyrazole-,N2)nickel(II)]-,-benzene-1,2,4,5-tetracarboxylato-,2O1:O4] tetrahydrate], {[Ni(C3H4N2)2(H2O)4][Ni(C10H2O8)(C3H4N2)2(H2O)2]·4H2O}n, (I), and poly[[(,4 -benzene-1,2,4,5-tetracarboxylato-,4O1:O2:O4:O5)octakis(1H -pyrazole-,N2)dicobalt(II)] tetrahydrate], {[Co2(C10H2O8)(C3H4N2)8]·4H2O}n, (II), are polymeric compounds crystallizing in the space group P, with two independent metallic cations and one benzene-1,2,4,5-tetracarboxylate (btc) anion, each lying on symmetry centres. Individual coordination polyhedra are regular and the main differences are in the way the btc anion binds [,2 in (I) and ,4 in (II)], promoting a `chain-like' one-dimensional structure in (I) and a `sieve-like' two-dimensional motif in (II). [source] Synthesis, structure and photoluminescence of two zinc carboxylate polymers with different coordination architecturesCHINESE JOURNAL OF CHEMISTRY, Issue 10 2003Hong Ding Abstract The hydrothermal reaction of ZnO with benzene-1,4-dicarboxylic add gave Zn·BDC·2H2O (1) and Zn-BDC·H2O (2) (BDC = benzene-1, 4-dicarboxylate), respectively. Polymer 1 (C4H4O3ZH0.5) shows a one-dimensional zigzag chain structure built up from the alternate connection of tetrahedral ZnO4 and BDC units. Polymer 2 (C4H3O2.5Zn0.5) possesses a three-dimensional framework containing infinite zigzag Zn·Zn·Zn pseudochains generated by five-coordinate zinc centers and a rectangular channel system including three groups of different straight channels along the [001], [010] and [60,1] directions. The two metal-organic polymeric compounds exhibit strong photoluminescent emission bands at 402 nm (,ex = 260 nm) (for 1) and at 344 nm and 385 nm (,ex = 279 nm) (for 2) in the solid state at room temperature. 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