Coordination Polymers of 1,9-Bis(8-Hydroxyquinolin-5-yl)-2,5,8-Trioxanonane

ABSTRACT

Coordination polymers of a novel bis(oxine) bidentate ligand, namely 1,9-bis(8-hydroxyquinolin-5-yl)-2,5,8-trioxanonane (BHQTN) (H₂L) have been prepared with the metal ions Zn⁺², Cu⁺², Ni⁺², Co⁺², and Mn⁺². The novel bis(bidentate) ligand BHQTN was synthesized by condensation of 5-chloromethyl-8-hydroxyquinoline hydrochloride with diethylene glycol in the presence of a base catalyst. All of these coordination polymers and the parent ligand were characterized by elemental analyses and IR spectral studies. The diffuse reflectance spectral studies and magnetic susceptibilities of all of the coordination polymers have also been performed. Thermogravimetric parameters such as T_o, T₁₀, T_max., IPDT, and the activation energy of the thermo-degradation process were calculated.     

An inelastic electron tunnelling spectroscopy (IETS) study of poly(vinylacetate) poly(methyl methacrylate) and poly(vinylalcohol) adsorbed on aluminium oxide

IETS is used to investigate the adsorption of poly(vinylacetate) (PVA), poly(methylmethacrylate) (PMMA), and poly(vinylalcohol) (PVOH) on aluminium oxide. These polymers are of interest in the field of adhesion science, and until now synthetic macromolecules have not been studied in this way. Both commercially available polymers and those synthesized in our laboratory have been used. On the basis of IET spectra presented here, and existing i.r. spectra it is believed that PMMA and PVA undergo ester cleavage at the oxide surface leading to their subsequent adsorption. For PMMA this is thought to be via carboxylate anions generated on the polymer side groups, while PVA is expected to be adsorbed as PVOH. Bonding of PVOH to the oxide is not fully understood, but may occur by the formation of an AlOC bridge. Another possibility for the above polymers, that of intermolecular hydrogen bonding between polar polymer side groups, and adsorbed hydroxyl species present on the oxide surface, cannot be ruled out.     

Synthesis and characterization of metal-containing coordination polymers of poly(methylene diphenylene terephthalamide)

Amino group-terminated poly(methylene diphenylene terephthalamide) (PMDTA) was prepared using a phosphorylation technique that was then converted into Schiff's base coordination polymers by their reaction with Co(II), Ni(II), and Cu(II) complexes of salicylaldehyde [M(SAL)₂] and 2-hydroxy-1-naphthaldehyde [M (NAPTHAL)₂]. The resulting coordination polymers were characterized by IR, elemental analysis, magnetic susceptibility measurements, and thermogravimetric analysis (TGA). TGA shows that coordination polymers are more thermally stable than is the ligand under similar conditions. On the basis of observed results, an oxygen-and nitrogen-coordinated structure for polyar-amid-metal complexes has been proposed. © 1993 John Wiley & Sons, Inc.     

Synthesis,Characterization and In Vitro Antibacterial Activity of Coordination Polymers Based on Bis Bidentate Ligand

A novel bis (bidentate) ligand, namely 5, 5′- (2, 2′- (phenyl azanediyl) bis (ethane-2, 1 - diyl) bis (oxy) bis (methylene) diquinolin ?8 - ol) (PBEQ), was synthesized by condensation of 5 –chloromethyl ?8 - hydroxyquinoline hydrochloride with N, N – Di (2 - hydroxy ethyl) aniline in the presence of a base catalyst. This ligand was characterized by IR, ¹H-NMR, and elemental analysis. Coordination polymers of this bis-ligand (PBEQ) were prepared with Cu(II), Ni(II), Co(II), Mn(II), and Zn(II) metal ions. All of these coordination polymers were characterized by elemental analyses, IR spectral and diffuse reflectance spectral studies. The thermal stability was evaluated by thermogravimetric analyses. In addition, all of the coordination polymers have been characterized by their magnetic susceptibilities. The microbicidal activity of all the samples has been monitored against plant pathogens.     

Preparation of poly(β-hydroxybutyrate) and poly(lactide) hollow spheres with controlled wall thickness

In recent years, polymer microcapsules have attracted more and more attention because of their specific properties and applications in encapsulation and drug delivery. Great effort has been made to investigate the preparation methods, structure controls as well as the property designs for the polymer microcapsules. In this work, we reported an effective route for the preparation of poly(β-hydroxybutyrate) (PHB) and poly(lactic acid) (PLA) hollow spheres with controlled wall thickness, which involves the graft polymerization of the biodegradable polymers from the surface of silica spheres followed by removing the template cores. Nuclear magnetic resonance spectroscopy (NMR), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscope (TEM) have been used to prove the structure of the hollow sphere and the intermediates. The result reveals that with the increase of reaction time the wall thickness of the hollow sphere will increase gradually.     

The Mannich bases in polymer synthesis: 3. Reduction of poly(β-aminoketone)s to poly(γ-aminoalcohol)s and their N-alkylation to poly(γ-hydroxy quaternary ammonium salt)s

Several poly(β-aminoketone)s, obtained by polyconensation of bis Mannich bases with bis (secondaryamine)s, have been quantitatively reduced to poly(γ-aminoalcohol)s. The stereochemistry of these polymers, as well as that of the reduction products of the parent bis Mannich bases has been investigated. By N-alkylation of the same polymers, poly(γ-hydroxy quaternary ammonium salt)s have been also prepared.     

Physicochemical properties of some new coordination polymers

Coordination polymers of Cu(II), Ni(II), CO(II), Mn(II), Zn(II), oxovanadium (IV), and dioxouranium(VI) with 2-hydroxy-4-methoxyacetophenone thiourea trioxane polymer were synthesized. Elemental analyses of the coordination polymers indicate a metal-to-ligand ratio of 1:2. The diffuse reflectance spectra and magnetic moments of coordination polymers show a distorted octahedral structure. Infrared spectral studies show that the metals are coordinated through the oxygens of carbonyl and phenolic groups and the nitrogen of thioamide group. Thermal stabilities of coordination polymers were determined by thermogravimetric analysis. Semiconducting behavior of the polymer and its coordination polymers was also studied by electrical conductivity measurements at different temperatures.     

Synthesis and characterization of poly(methylene disulfide) and poly(ethylene disulfide) polymers in the presence of a phase transfer catalyst

Poly(methylene disulfide) and poly(ethylene disulfide) were synthesized from the polycondensation of methylene dichloride and ethylene dichloride monomers, respectively, in the presence of benzyltriethylammonium chloride as a phase transfer catalyst. The structures of the synthesized polysulfides were confirmed via the elemental analysis, attenuated total reflectance Fourier transform infrared spectroscopy and X-ray diffraction techniques. Moreover, the thermal behaviors of synthesized poly(methylene disulfide) and poly(ethylene disulfide) were characterized using differential scanning calorimetry and thermogravimetric analysis methods. The synthesized poly(methylene disulfide) and poly(ethylene disulfide) have molecular weights of about 2262 and 2863 g/mol, respectively. In addition, the polymers have crystalline structures absorbed in the amorphous sections. However, the d-spacing of polymers’ crystalline parts was different. Moreover, poly(methylene disulfide) and poly(ethylene disulfide) have a two- and one-step degradation behavior, respectively.     

Design of novel poly(methyl vinyl ether) containing AB and ABC block copolymers by the dual initiator strategy

A new set of block copolymers containing poly(methyl vinyl ether) (PMVE) on one hand and poly(tert-butyl acrylate), poly(acrylic acid), poly(methyl acrylate) or polystyrene on the other hand, have been prepared by the use of a novel dual initiator 2-bromo-(3,3-diethoxy-propyl)-2-methylpropanoate. The dual initiator has been applied in a sequential process to prepare well-defined block copolymers of poly(methyl vinyl ether) (PMVE) and hydrolizable poly(tert-butyl acrylate) (PtBA), poly(methyl acrylate) (PMA) or polystyrene (PS) by living cationic polymerization and atom transfer radical polymerization (ATRP), respectively. In a first step, the Br and acetal end groups of the dual initiator have been used to generate well-defined homopolymers by ATRP (resulting in polymers with remaining acetal function) and living cationic polymerization (PMVE with pendant Br end group), respectively. In a second step, those acetal functionalized polymers and PMVE-Br homopolymers have been used as macroinitiators for the preparation of PMVE-containing block copolymers. After hydrolysis of the tert-butyl groups in the PMVE-b-ptBA block copolymer, PMVE-b-poly(acrylic acid) (PMVE-b-PAA) is obtained. Chain extension of the AB diblock copolymers by ATRP gives rise to ABC triblock copolymers. The polymers have been characterized by MALDI-TOF, GPC and ¹H NMR.     

Coordination polymers, 1. Magnetic,spectral, and thermal properties of coordination polymers derived from terephthalaldehyde bis(S-benzyldithiocarbazate)

New Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) coordination polymers of Schiff base ligand derived from terephthalaldehyde and S-benzyldithiocarbazate have been synthesized in DMF media. The coordination polymers have been characterized by their elemental analysis, magnetic susceptibility, and by electronic and infrared spectral measurements. The thermal stability of each polymer was found out by thermogravimetric analysis. The thermal stability of coordination polymers obtained from thermograms has the following order: $ {\rm Zn} \simeq {\rm Fe} > {\rm Co} > {\rm Ni} > {\rm Min} \simeq {\rm Cu}$ Mn(II), Fe(II), Co(II), and Ni(II) coordination polymers are of a six-coordinated octahedral structure while Cu(II) and Zn(II) coordination polymers are found to be four-coordinated square planar and tetrahedral structure, respectively. The ligand-field and nephelauxetic parameters have been determined from the spectra, using ligand-field theory of spin-allowed transitions which are found consistent with six-coordinate structure for Mn(II), Fe(II), Co(II), and Ni(II) coordination polymers. Elemental analyses indicates a ligand: metal ratio of 1 : 1 in all the coordination polymers and the association of water molecules with central metal atom in case of Mn(II), Fe(II), Co(II), and Ni(II) coordination polymers.     

Formation of interpolymer complexes between poly(monoethyl itaconate) and poly(N-vinyl-2-pyrrolidone)

This paper reports on the interpolymer complex formation and polymer blends between poly(monoethyl itaconate) (PMEI) and poly(N-vinyl-2-pyrrolidone) (PVP). The formation of the interpolymer complex was found to depend upon the solvent medium. Stoichiometry of the complexes prepared from methanol solutions, as calculated from elemental analysis, is close to 1 : 1. Specific interactions of PMEI/PVP complexes and blends of these polymers have been characterized by FTIR. Strong hydrogen bonding for complexes and blends has been found. A calorimetric study of the complexes and blends has been performed over a wide temperature range.     

Thermal analysis of poly(1,3,4-oxadiazole-2,5 diyl-1,2-ethenediyl) and poly(1,4-phenylene-1,3,4-oxadiazole-2,5 diyl-1,2 ethendiyl)

Poly(1,3,4-oxadiazole-2,5-diyl-1,2-ethendiyl) and poly(1,4-phenylene-1,3,4-oxadiazole-2,5 diyl-1,2-ethenediyl) have been prepared by condensation polymerization using fuming sulfuric acid and different quantities of terephthalic acid (T), fumaric acid (F), and hydrazine sulfate (HS). Homopolymers of F and T and various copolymers of F:T have been prepared. The polymer structure was investigated by IR and visible-range spectra and elemental analysis. The existence of poly(1,3,4-oxadiazole-diylphenylene) and poly(hydrazoterephthaloyl) structures was revealed by these studies. These polymers were thermally stable, and most of them did not show a weight loss below 350°C. The relative thermal stabilities of the various polymers have been evaluated by “integral procedural decomposition temperature” and activation energy measurements.     

On the cytotoxicity of poly(4-aminodiphenylaniline) powders: Effect of acid dopant type and sample posttreatment

Thanks to their unique properties, as intrinsic conductivity and simple preparation, conducting polymers are highly applicable in tissue engineering, regenerative medicine, and biosensors. Pristine polymers often include residual precursors or other low molecular impurities, which have a negative impact on their biocompatibility. Concerning poly(4-aminodiphenylaniline), its cytotoxicity and biocompatibility have not yet been investigated. Herein, the cytotoxicity of poly(4-aminodiphenylaniline), prepared by an innovative green approach, as well as the effect of samples’ posttreatment and kind of dopant acid used, are reported for the first time. The results show that not only the type of used dopant but also polymers’ washing in phosphate saline buffer and material’s morphology has a significant impact on materials’ cytotoxicity. After a proper posttreatment or when salicylic acid is used as the doping agent the cytotoxicity of poly(4-aminodiphenylaniline) seem to be lower than those obtained for traditional PANI.     

Synthesis and characterization of piperazine-derived poly(amido-amine)s with different distributions of amido- and amino-groups along the macromolecular chain

Four poly(amido-amine)s based on piperazine have been synthesized by poly(acylation-addition) reaction of piperazind with various activated derivatives of acrylic acid. In these polymers, amido-, and amino groups are randomly arranged along the macromolecular chain. These polymers have been fully characterized by hydrolytic analysis, ¹³C n.m.r., and potentiometric techniques.     

Novel perfluorocyclobutyl (PFCB)-containing polymers formed by click chemistry

The synthesis and characterization of a novel class of linear poly(alkyl aryl) ethers containing 1,2,3-triazolyl and perfluorocyclobutyl units have been described. These polymers were readily prepared from the Huisgen's 1,3-dipolar cycloaddition of poly(ethylene glycol) diazides and 1,2-bis(4-ethynylphenoxy)perfluorocyclobutane that is defined as ‘click chemistry’ recently. These polymers exhibited relatively small polydispersity, good thermal stability and solubility in common organic solvents.     

Thermal degradation of poly(2-methylphenylene oxide), poly(2,5-dimethylphenylene oxide) and poly(1,4-phenylene oxide)

Polyoxyphenylenes were obtained from phenol, 2-methylphenol, 2,5-dimethyl-phenol in oxidative polycondensations using dimethylpyridineCuCl complexes as catalysts. Samples of polymers from polycondensations were not completely linear as found by i.r. analysis. The m.s. and c.c.—m.s. analysis of degradation products of poly(2-methylphenylene oxide) (PMPO) and poly(2,5-dimethylphenylene oxide) (P2, 5DMPO) have shown that both polymers undergo Fries-type rearrangement prior to statistical scission of benzyl bonds. Ether linkages of poly(1,4-phenylene oxide) (PPO) decompose without rearrangement though cyclization to benzofurane systems has been observed.     

Poly(aryl ether sulfide)s by sulfide-activated nucleophilic aromatic substitution polymerization

Poly(aryl ether sulfide)s have been produced by nucleophilic aromatic substitution with phenoxide nucleophiles bisphenol A and bisphenol AF, and the activated arylfluorides bis(4-fluorophenyl)sulfide and 2,7-difluorothianthrene. The resulting polymers are thermally stable, amorphous materials that have been characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and gel permeation chromatography (GPC). Moderate molecular weights have been achieved, representative of greater than 98% conversion of arylfluorides. The poly(aryl ether thianthrene)s are flame resistant and self extinguish within 0.2 s upon removal from a flame source. TGA of the poly(aryl ether thianthrene)s in an inert atmosphere result in a char yield greater than 50% at 750 °C. The flame resistant properties are more effectively modeled by TGA in an inert atmosphere as compared to TGA in an air atmosphere. The poly(aryl ether thianthrene)s are found to have high refractive index values, 1.61-1.70, depending on wavelength and bisphenol composition.     

Study of ternary component polymer complexes of poly(methacrylic acid) and poly(acrylic acid) with complementary polymers

Ternary component polymer complexes have been prepared from poly(acrylic acid) and poly(methacrylic acid) with complementary polymers, such as poly(vinylpyrrolidone) and poly(ethylene oxide). The formation of ternary complexes, selective complexation, and mutual compatibility of the complementary polymers attached to the same polycarboxylic acid chain, have been studied by several techniques, such as viscometry, turbidimetry, potentiometry, conductometry, and IR spectra.     

Studies of polymer electrets. I. Factors governing the stabilities of homoelectrets obtained from poly(1-olefin)s

Various poly(1-olefin)s have been studied as homoelectrets and their stabilities under different environmental conditions have been determined. It has been found that the stabilities of the homoelectrets, prepared from these polymers, depend on their volume resistivities, degrees of crystallinity, and the temperatures at which the crystalline domains of these polymers undergo transitional motions. Excellent stabilities have been exhibited by the homoelectrets prepared from poly(3-methyl-1-butene), poly(4-methyl-1-pentene) and other similar isotactic poly(1-olefin)s with pendant branched side chains. It is postulated that the charged particles are trapped at the crystalline/amorphous interfaces in these polymers and the bulky alkyl substituents stabilize the charged particles by raising the transition temperatures of these polymers as well as by providing some additional chemical interaction sites.     

Structures and properties of highly sulfonated poly(arylenethioethersulfone)s as proton exchange membranes

A series of sulfonated poly(sulfonium cation) polymers, sulfonated poly(arylenethioethersulfone)s (SPTES)s possess up to two sulfonate groups per repeat unit, and can be easily converted into corresponding acid form of the SPTES polymer to form a tough, ductile, free-standing, pinhole-free membranes with excellent mechanical properties. The SPTES polymers exhibit good water affinity and excellent proton conductivity due to the high water uptake. Proton conductivities between 100 and 300 mS/cm (at 65 °C, 85% relative humidity) were observed for the SPTES polymers with 50 mol% (SPTES-50) to 100 mol% (SPTES-100) of sulfonated monomer. The evaluation by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermomechanical analysis (TMA) showed that the SPTES polymers have excellent thermal stability, mechanical properties, and dimensional stability, making them excellent candidates for the next generation of proton exchange membranes (PEMs) in fuel cell applications.