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A new method based on the retention of ions by hydrophilic polymer reagents in a membrane filtration system, called Liquid-Phase Polymer-Based Retention, is described for selective ion separation. The principle and fundamentals of the method including the use of polychelatogens are explained and discussed. The effect of several polychelatogens on ion separation is documented and described by numerous retention profiles. It is shown that LPR is a convenient and effective method for selective ion separation of metal ions and anions.

Radikalische Copolymerisationen einer Reihe von Aminosaure-alkenylestern (1a–e) mit 1-Vinyl-2-pyrrolidinon (2) und 2,2′-Azoisobutyronitril als Starter werden beschrieben. Die erhaltenen Polymere sind sowohl in Wasser als auch in zahlreichen organischen +osungsmitteln leicht loslich und konnen als Tragerpolymere zur Synthese von Peptiden verwendet werden. Aus dem Copolymer 3a, aus 2 und N-tert-Butyloxycarbonylalanin-vinylester (1a), wird nach Abspaltung der Aminoschutzgruppe 3b erhalten, an das eine weitere Aminosaure gekuppelt wird. Dies zeigt, das an den dargestellten Copolymeren polymeranaloge Umsetzungen durchgefuhrt werden konnen. The radical copolymerisation of a series of amino acid alkenyl esters (1a–e) with 1-vinyl-2-pyrrolidinone (2) and with 2,2′-azoisobutyronitrile as initiator are described. The obtained copolymers are soluble in water as well as in numerous organic solvents. They can be used as polymeric supports for the synthesis of peptides. After cleavage of the amino protecting group in the copolymer 3a prepared from 2 and N-tert-butyloxy-carbonylalanine vinylester, the resulting copolymer 3b can be coupled with another amino acid. This shows the possibility of polymeranalogous reactions with the prepared copolymers.

Living oligomers of ethylene obtained by sec-butyllithium complexed with tetramethylethylenediamine (TMEDA) were deactived by oxygen. NMR and mass spectrometry, coupled with gas chromatography of the resulting product allowed us to follow the influence of TMEDA towards functionalization. The two products were characterized. Apparently the ratio [TMEDA]/[sec-BuLi] does not seem to influence the functionalization reaction.

Synthesis of Mono- and Divinyl Ethers of Tetra(oxyethylene) The derivatives 3, 4, and 6 – 8 of tetra(oxyethylene) (1) are prepared. 3, 4, and 8 are obtained by direct vinylation in the presence of vinyl acetate and mercury acetate. 6 and 7 are prepared by esterification of 1 with 3,5-dinitrobenzoyl chloride (5) and represent intermediates for the hydroxy protected vinyl monomer 8.

In a first example of the functionalization of soluble polymers the conversion of the hydroxyl groups of poly(oxyethylene) into primary amino groups has been studied. Starting from poly(oxyethylene), the preparation of the diphthalimido derivative via the disodium salt is described. Prom this regiospecific functionalized polymer the di(aminoethyl) poly(oxyethylene), which exhibits excellent solubility properties, can be obtained by polymeranalogous hydrazinolysis.

Polyurethanes 6 and 7 based on poly(oxyethylene) (5) were synthesized and investigated for the application as macromolecular chelating agents. 4,4′-Diaminobenzil (3c) and 4,4′-diaminobenzil monoxime (4a) were prepared as monomer precursors in 70 and 80% yield. Copolymers were obtained in yields between 40 and 60% by polyaddition of the corresponding diisocyanates 3d and 4b to poly(oxyethylene) (5) of different chain length and characterized by IR and 13C NMR spectroscopy. The application of the resulting polyurethanes containing functional aromatic block units as polychelatogenes was studied in homogeneous phase by membrane filtration. The metal content was determined in both the filtrate and the retentate and in the case of Ni2+ at different pH values. At pH 2, for example, the molar binding capacity of a polyurethane sample of 6 was 3 times as high as that of 5.

Makromolekulare Chelatogene wurden zur Komplexierung mit verschiedenen Metallen in homogener Phase unter Anwendung der Membranfiltration synthetisiert und untersucht. Eine Anzahl von wasserloslichen Basispolymeren, wie z. B. Poly(vinylamin), Poly(acrylsaure), Poly(ethylenimin), ihre Copolymere und Derivate wurden im Hinblick auf ihre Anwendung zur Komplexbildung von Ubergangsmetallen dargestellt und untersucht. Die Molmassen der Polymere lagen zwischen 20000 und 200000 Daltons. Die Anwendung der Membranfiltration ermoglicht die Abtrennung von uberschussigen Metallionen vom Polymerkomplex in einem kontinuierlichen oder diskontinuierlichen Verfahren. Studien uber die Metallbindungskapazitaten der Polymerliganden zeigten, das es moglich ist, makromolekulare Chelatogene darzustellen, die fur verschiedene Metalle selektiv sind. Danach verbesserte die Einfuhrung von chelatogenen Gruppen, wie Iminodiessigsaure, Thioharnstoff, Pyridin-2-aldimin und andere, signifikant die Selektivitat fur die Metalle Kupfer, Nickel, Palladium, Quecksilber, Eisen, Gold und Platin. Zur Regenerierung der Polymerliganden kann die Elektrolyse oder Protolyse verwendet werden. Die makromolekularen Komplexe blieben unabhangig vom komplexierten Metall und des polymeren Chelatogens wasserloslich. Nach diesen Studien konnen bestimmte Metalle selektiv aus Abwasser oder anderen verdunnten Losungen durch die Anwendung von polymeren Chelatogenen in homogener Phase entfernt werden. Macromolecular chelating agents have been synthesized and investigated for the complexation with various metals in homogeneous phasing using membrane filtration. Quite a number of water-soluble basis polymers such as poly(vinylamine), poly(acrylic acid), poly(ethyleneimine), and copolymers, and their derivatives are listed and discussed in respect to their application for the chelation of transition metals. The polymers had molecular masses between 20000 and 200000 daltons. The application of membrane filtration rendered it possible to separate excess metallic ions from the polymer chelate in a continuous or discontinuous process. Studies on the metal-binding capacity of the polymer ligand exhibited the possiblity of preparation of macromolecular chelating agents which are selective for different metals. There after, the introduction of chelating groups such as iminodiacetic acid, thiourea, pyridine-2-aldimine, and others, improved significantly the selectivity for the metals copper, nickel, palladium, mercury, iron, gold, and platinum. For the regeneration of the polymer ligands electrolysis and protolysis can be used. The macromolecular chelates remained water-soluble independent of the chelated metal and the polymeric chelating agent. According to these studies, certain metals can be removed selectively from waste water or other diluted solutions in homogeneous phase by the application of polymeric chelating agents.

1,2,3,4-Tetrahydroxypentane-29-hopane (THBH) and a glycolipid derived from it are associated with ω-cyclohexane fatty acids-containing lipids in the membrane of Bacillus acidocaldarius . In order to elucidate the function of these lipids we studied mixed monolayer films and compared these with cholesterol-containing films. The hopanoids are able to condense a liquid-expanded film of di-ω-cyclohexyldodecanoylphosphatidylcholine (DCDPC). The condensing effect of THBH is smaller than that of cholesterol. Hopane glycolipid in comparison shows only little condensation. In a more condensed film, at lower temperatures, THBH slightly decreases while hopane glycolipid increases the molecular area. In egg phosphatidylcholine liposomes, 22-hydroxyhopane (diplopterol) and hopane glycolipid reduce the glycerol permeability to a smaller extent than cholesterol. In DCDPC liposomes, the effect of 22-hydroxyhopane is similar to that of cholesterol, while the hopane glycolipid shows only a weak reduction of the permeability. The results demonstrate that hepanoids have a cholesterol-like function in membranes. This function is also discussed in the context of membrane adaptation of a thermoacidophilic bacterium.

Synthese und Eigenschaften der Aminosaure-alkenylester 1–7 werden beschrieben. Die Darstellung der Vinylester 1–6 erfolgt durch Austausch mit Vinylacetat unter Natriumtetrachloropalladat(II)-Katalyse. Allylester werden durch Veresterung der N-geschutzten Aminosaure mit Allylakohol dargestellt. Die Ausbeuten liegen zwischen 60 und 90%. Synthesis of Amino Acid Alkenyl Esters The synthesis and the properties of the amino acid alkenyl esters 1–7 are described. The vinyl esters 1–6 are prepared by a exchange reaction with vinyl acetate by sodium tetrachloropalladate(II) catalysis. Allyl esters are prepared by esterification of the N-protected amino acids with allyl alcohol. The yields are between 60 and 90%.

Poly(1-aminoethylene) (polyvinylamine) (4) was prepared by hydrazinolysis of poly(1-succinimidoethylene) (2) [poly(N-vinylsuccinimide)]. The water-soluble polymer 4, with more than 95% of primary amino groups, was used as basic material for the synthesis of macromolecular complex forming reagents. By the reaction of poly(1-ammonioethylene chloride) (3) [poly(vinylamine hydrochloride)] with 2-pyridinecarbaldehyde a complex forming polymer 5 was obtained, which is highly selective for iron. Poly{1-[bis(carboxymethyl)amino]ethylene} (6) from 4 and chloroacetic acid is a reagent for copper, whereas poly[1-(3-methylthioureido)-ethylene] (7) from 4 and N-methylisothiocyanate shows a good selectivity for mercury. The ultrafiltration technique allows a continuous procedure for the separation of the polymer complexes. The formation and stability of the prepared complexes of 4and its derivatives 5, 6, and 7 in homogeneous phase are investigated and discussed.

A method based on the retention of inorganic ions by water-soluble polymeric reagents (liquid-phase polymer-based retention) in a membrane filtration cell is suggested for the separation and preconcentration of various elements. The preseparated elements remain in the aqueous solution, which is convenient for most instrumental methods of completing the analysis. The water-soluble poly(ethyleneimine) and its thiourea and methylated derivatives are shwon to be useful for retention of different inorganic ions and their separation from elements not bound to the polymer reagent.

A method for the rapid determination of primary amino groups on soluble polymers is described and discussed. After reaction of the amino groups with fluorescamine, the relative fluorescence is measured. The calibration and application of the procedure in practice is demonstrated for two copolymers of 1-vinyl-2-pyrrolidinone with alanine vinylester or allylamine.

Preconcentration and recovery of arsenic from diluted aqueous solutions by soluble polymeric reagents in combination with membrane filtration were investigated. Quaternized poly(ethyleneimine) was found to be an efficient reagent for removal of arsenic and for separation of As(III), As(V), and divalent metal cations such as Cu, Cd, Zn, and Co. Using a 4% solution of the polymer reagnet, 98% of arsenic(V) was retained at pH 8.5, which could be stripped off by addition of a 0.15 M solution of a sodium salt solution at the same pH. A practical application was demonstrated by the removal of more than 95% of As(V) from actual concentrations of arsenic in wastewater.

Separation of metal ions by functionalized soluble polymers using membrane filtration has been investigated. Actinide elements and members from the transition groups and rare earth elements have been bound to polymeric chelatogenes as a function of pH. Sixteen different polymers and derivatives based on poly(ethylenimine), poly(vinylalcohol), poly(urethane), and poly(acrylic acid) have been studied in terms of their capacity and selectivity. Binding studies and cleavage experiments have been carried out by application of membrane filtration for several metals and polychetatogenes. Finally, the stability of polymers and membranes has been studied and found to be sufficient for selective separation of actinide ions.

The problems of solvent extraction and ion-exchange-based quantitative enrichment of anions having high hydration energies in aqueous solutions using water-insoluble quaternary ammonium salts are discussed. A new approach to anion exchange extraction of such anions by water-soluble polymeric quarternary ammonium salts is suggested in conjunction with membrane filtration. The retention of oxo anions of arsenic(V)r phosphorus(V), chromium(VI), selenium(IV) and of the fluoride ion with the permethylated derivative of poly-(ethyleneimine) and the influence of different salts on the retention of the anions have been studied and the possibility of quantitative retention of these anions has been demonstrated. For example, the retention for arsenic(V) was found to be 92% and 89% for fluoride with 2% polymer and a filtration factor of seven. After extraction the oxo anions can be stripped off easily in the cell solution up to 99% by 0.1 M HCl or a 0.15 M solution of sodium salts.

Du polystyrene reticule contenant des groupes chloromethyle est transforme en polyarylether contenant des aldehydes par reaction en une etape avec l'hydroxy-4 benzaldehyde

Synthesis and application of several polymeric agents based on poly(vinylalcohol) with phosphorus containing functional groups were investigated. Monomer and polymer syntheses of phosphoric acid and derivaties with poly(vinylalcohol) are described. Multifunctional derivaties of the hydrophilic polymer were obtained by polymer-analogous reactions with mono and diethyl esters of phosphoric acid. Studies on chelating properties of the polychelatogenes at different pH values for nickel were carried out by means of membrane filtration. Metal determination in filtrate and retentate yielded typical chelating curves. Differences of the polymer supports and influences of the functional groups are discussed. Die Synthese und Anwendung von mehreren polymeren Agentien auf der Basis von Poly(vinylalkohol), die funktionelle Gruppen mit Phosphor enthalten, wurde untersucht. Die Monomer- und Polymersynthese von Phosphorsaure und ihrer Derivate mit Poly(vinylalkohol) werden beschrieben. Durch polymeranaloge Reaktionen mit Mono- und Diethylestern der Phosphorsaure wurden multifunktionelle Derivate dieses hydrophilen Polymers erhalten. Untersuchungen zu den Komplexbildungseigenschaften der Polychelatogene wurden mit Hilfe der Membranfiltration fur Nickel bei verschiedenen pH-Werten durchgefuhrt. Typische Komplexierungskurven wurden nach Bestimmung des Metallgehalts im Filtrat und Retentat erhalten. Unterschiede der polymeren Trager und Einflusse der funktionellen Gruppen werden diskutiert.

An einem loslichen Trager wurde das Tetrapeptid HAlaGlyLeuAlaOH synthetisiert. Der Trager ist ein Copolymer von 1-Vinyl-2-pyrrolidinon und Vinylacetat, das in einer polymeranalogen Umsetzung hydrolysiert wurde. Die so erhaltenen Hydroxyguppen wurden als funktionelle Gruppen zur Fixierung der ersten Aminosaure an den Trager benutzt. Als Aminoschutzgruppe wurde die tert.-Butyloxycarbonylgruppe verwendet. Die Kupplungen erfolgten nach der Dicyclohexylcarbodiimid-Methode. Die niedermolekularen Uberschusse wurden durch Ultrafiltration abgetrennt. Soluble Copolymers of 1-Vinyl-2-2pyrrolidinone and vinyl Acetate for the Synthesis of Peptides**) The tetrapeptide HAlaGlyLeuAlaOH was synthesized on a soluble support consisting of a copolymer of 1-vinyl-2-pyrrolidinone and vinyl acetate which was hydrolysed in a polymeranalogous reaction. The hydroxyl groups so obtained were used as functional groups for the fixation of the first amino acid to the support. The tert-butyloxycarbonyl group was used as amino-protecting group. Coupling was carried out by the dicyclohexylcarbodiimide method. The low-molecular excesses were separated by ultrafiltration.

The interactions of the polymeric backbone and complex formation with a series of metals were investigated for poly(ethyleneimine), poly(vinylpyrrolidinone), and poly-(acrylamide) as basis polymers with methylthiourea as ligand. Retention studies by application of membrane filtration of aqueous solutions were used for the evaluation of interaction between the metal ions and macromolecules as function of pH. It was shown for the Na, Co, Ni, Cu, Zn, Cd, Hg, Fe ions that the interaction depends both on the type of polymer backbone and the pH. Whereas for poly(ethyleneimine)-based copolymers the retention data were influenced only slightly by pH, the two other copolymers investigated showed a strong pH dependency for the individual metals. A dominating effect of the functional ligand comonomer in terms of the interaction over the basis monomer was observed for the majority of metal ions investigated. Die Wechselwirkungen des Polymergerusts und die Komplexbildung mit einer Reihe von Schwermetallen wurde fur die Methylthioharnstoff als Liganden tragenden Basispolymeren Poly(ethylenimin), Poly(vinylpyrrolidinon) und Poly(acrylamid) in Abhangigkeit vom pH-Wert untersucht. Retentionsstudien in wassriger Losung unter Verwendung von Membranfiltration wurden zur Bewertung der Wechselwirkungen zwischen Metallionen und Makromolekulen in Abhangigkeit vom pH-Wert herangezogen. Es wurde fur die Ionen Na, Co, Ni, Cu, Zn, Cd, Hg, Fe gezeigt, das die Wechselwirkung sowohl von der Art des Polymergerusts als auch vom pH abhangt. Wahrend die Retentionswerte von Copolymeren auf der Basis von Poly(ethylenimin) nur schwach vom pH beeinflust wurden, zeigten die beiden anderen untersuchten Copolymeren eine starke Abhlngigkeit fur die einzelnen Metalle. Es wurde eine vorherrschende Wirkung des funktionellen Liganden-Comonomeren hinsichtlich der Wechselwirkung im Vergleich zum Basismonomeren fuur den grosten Teil der untersuchten Metallionen gefunden.

The oligomerization of ethylene in hexane, initiated by sec-butyllithium (sec-BuLi) complexed with tetramethylethylenediamine (TMEDA) was studied. The half-order reaction in [sec-BuLi-TMEDA] and [PELi-TMEDA] (PELi = (polyethylene)lithium) supports the presence of aggregated dimer species. For the initiation as well as the propagation, a dissociation of these dimers (sec-BuLi-TMEDA)2 and (PELi-TMEDA)2 has to be considered, the monomeric form being the only active one. The higher reactivity of sec-BuLi compared to PELi can be explained partly by a secondary carbanionic structure compared to a primary one.

We demonstrated for the first time that nonionic surfactants such as T-80 not only act as stabilizing or protecting agents, but also can act as reducing agents for a facile “one-pot” synthesis of gold nanoparticles in an aqueous medium with tunable size at ambient conditions.

The importance of trace-element analysis in geological, biological, environmental and industrial processes has been increasingly recognized. Although modern instrumental methods of analysis have been applied, preliminary enrichment techniques are required to separate the components to be determined from the interfering constituents of the sample1,2. For the separation of inorganic ions contained in natural waters, industrial fluids or dissolved solid materials, solvent extraction, sorption, ion exchange, precipitation and other methods have been used. However, techniques based on a two-phase distribution or on heterogeneous reactions often cause problems because, in contrast with homogeneous reactions, diffusion controlled processes must be used. Until now, no simple, rapid method has been available for the preconcentration and separation of metals in the homogeneous aqueous phase. Here we demonstrate a technique for the enrichment and separation of metals in aqueous solution using soluble non-crosslinked polymers with chelating groups (polychelatogens)3,4 called liquid-phase polymer-based retention (LPR).

Living oligomers of ethylene obtained using sec-butyl-lithium complexed with tetramethylethylenediamine (TMEDA) were deactivated by oxygen. Mass spectrometry coupled with gas chromatography of the resulting product allowed the determination of the molecular mass distribution of the alcohols, the coupled products as well as the non-oxidized products formed.

A new method for the determination of metals in waters by flame atomic-absorption spectrometry is described. The metals are retained by water-soluble polymers in a membrane filtration cell and the factors which influence their determination are discussed. The method has been applied to the determination of Ni, Cu, Zn, Hg and Cd in drinking and river water with poly(ethyleneimine) and its thiourea derivative as complexing polymers. The metals were determined in the aqueous concentrate after a 250-fold preconcentration by 2% polymer solution at pH 7. The metal recoveries were at least 92%, and the limits of detection (ng/mg) were 0.012 for Cu, 0.006 for Zn, 0.03 for Ni, 0.004 for Cd and 0.0001 for Hg (cold vapour method). When a new type of membrane filtration cell is used even higher preconcentration factors can be achieved and lower concentrations can be determined.

Die Darstellung der Titelverbindung, ausgehend von 2,3-Indolindion (1), wird beschrieben. A Convenient Synthesis of 1,2,3-Benzotriazin-4(3H)-one Preparation of the title compound, starting from 2,3-indolinedione (1), is described.