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The article presents the results of a study involving the crystallization structures of injection-molded bars of polypropylene (PP). Differential scanning calorimetry and wide angle X-ray diffraction were used to find the distribution of beta-phase PP in the skin layer, intermediate layers and core of the bars. Both alpha-phase and beta-phase PP were found in the skin layer of the injection-molded bars, regardless of whether the PP was nucleated or not. In the other zones, the nucleating agent determined crystallization structure.

A novel cadmium(II) coordination polymer, poly[[[bis­(4,4′-bipyridine)cadmium(II)]-μ3-4,4′-dicarboxy­biphenyl-3,3′-di­carboxyl­ato] 0.35-hydrate], {[Cd(C16H8O8)(C10H8N2)2]·0.35H2O} n, was obtained by reaction of Cd(CH3COO)2·3H2O, 4,4′-bipyridine (4,4′-bpy) and biphenyl-3,3′,4,4′-tetra­car­boxylic acid (H4 L) under hydro­thermal conditions. Each CdII atom lies at the centre of a distorted octa­hedron, coordinated by four O atoms from three H2 L2− ligands and N atoms from two monodentate 4,4′-bpy ligands. Each H2 L2− ligand coordinates to three CdII atoms through two carboxyl­ate groups, one acting as a bridging bidentate ligand and the other in a chelating bidentate fashion. Two Cd atoms, two H2 L2− anions and four 4,4′-bpy ligands form a ring dimer node, which links into an extended broad zonal one-dimensional chain along the c axis. [ABSTRACT FROM AUTHOR]

The novel title ZnII coordination polymer, poly[bis(μ-6-thioxo-1,6-dihydropyridine-3-carboxylato-κ2 S: O)zinc(II)], [Zn(C6H4NO2S)2] n, consists of two crystallographically independent zinc centers and two 6-mercaptonicotinate (Hmna−) ligands. Each ZnII atom is four-coordinated and lies at the center of a distorted tetrahedral ZnS2O2 coordination polyhedron, bridged by four Hmna− ligands to form a two-dimensional (4,4)-network. Each Hmna− ion acts as a bridging bidentate ligand, coordinating to two ZnII atoms through the S atom and a carboxyl O atom. The metal centers reside on twofold rotation axes. The coordination mode of the S atoms and N—H...O hydrogen-bonding interactions between the protonated N atoms and the uncoordinated carboxyl O atoms give the extended structure a wavelike form. [ABSTRACT FROM AUTHOR]

A new one-dimensional coordination polymer, catena-poly­[[aqua­(nitrato-κ2 O,O′)copper(II)]-μ-pyrazine-2-carboxyl­ato- κ3 N1, O:N4], [Cu(C5H3N2O2)(NO3)(H2O)] n, has been synthesized and characterized. The coordination environment of the copper(II) ion is distorted octahedral, arising from an N, O-bidentate 2-pyrazine­carboxyl­ate ligand, an N atom from a symmetry-related 2-pyrazine­carboxyl­ate ligand, a bidentate nitrate group and a water mol­ecule. The chains interact by way of O—H⋯O hydrogen bonds and C—H⋯O interactions. [ABSTRACT FROM AUTHOR]

The title cobalt(II) coordination polymer, [Co(C16H8O8)(C10H8N2)2] n, was obtained by the reaction of Co(OAc)2·4H2O (OAc is acetate), 4,4′-bipyridine (4,4′-bpy) and biphenyl-3,4,3′,4′-tetra­carboxylic acid (H4 L) under hydro­thermal conditions. Each CoII atom lies at the centre of a distorted octa­hedron, coordinated by four O atoms from three H2 L2− and two N atoms from two monodentate 4,4′-bpy ligands. Each H2 L2− ligand coordinates to three CoII centres through two carboxyl­ate groups, one acting as a bridging bidentate group and the other in a chelating bidentate fashion. Two Co atoms, two H2 L2− and four 4,4′-bpy ligands form a ring dimer node, and these nodes link into an extended broad chain along the c axis. [ABSTRACT FROM AUTHOR]