bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of polystyrene resin with pendant vicinal dioxime groups
Authors: Biçak Niyazi , Atay Tülay , Koza Güneş 
Published: April 2003

AbstractPreparation of macroporous polystyrene beads having pendant vicinal dioxime groups and their metal chelating ability is described. Acetylated polystyrene resin crosslinked with 2 mol‐% divinyl benzene was oxidized with SeO2 to give the polymer bearing glyoxyloyl side groups. Then, treating with hydroxylamine, the polymer possessing dioxime groups was obtained. Metal absorbtivity and decomplexation of the resulting polymeric resin were investigated in a wide pH range.
Etude de l'oxydation de polystyrènes chlorométhylés renfermant de nouveaux radicaux tétrathiafulvalénylcarbonyloxyméthyles
Authors: Mora Henri , Fabre Jean‐Marc , Giral Louis , Montginoul Claude , Sagnes René , Schué François 
Published: April 2003

AbstractLes polystyrènes chlorométhylés renfermant des radicaux tétrathiafulvalénylcarbonyloxyméthyles peuvent être oxydés. Ainsi la formation de sels d'ions radicaux obtenus à partir de ces polymères et de tétrabromure de carbone, irradiés sous UV, a été mise en évidence. Des complexes de transfert de charge ont été préparés en mettant en présence ces polymères et de la 2,3‐dichloro‐5,6‐dicyanobenzoquinone. La présence de sulfoxydes non décelés et résultant de l'oxydation de certaines unités de tetrathiafulvalène contenus dans ces polymères pourrait expliquer les problèmes rencontrés lors de la filtration de leurs solutions.
Preparation and uranyl ion adsorptivity of macroreticular chelating resins containing phosphono groups
Authors: Park In‐Hwan , Jung Jin‐Chul , Hwang Sung‐Chan , Joo Jae‐Oh 
Published: April 2003

AbstractMacroreticular copolymer beads were prepared by suspension polymerization of styrene, bis(2‐chloroethyl) vinyl phosphonate (CEVP) and divinylbenzene (DVB) in the presence of toluene as diluent. The bis(2‐chloroethyl) phosphonate groups on the bead surface were converted into phosphono groups by hydrolysis with dilute nitric acid. For the additional enrichment of phosphono groups, the copolymers were phosphorylated at the phenyl rings with phosphorus trichloride in the presence of aluminum chloride and hydrolyzed and oxidized with dilute nitrics acid. The investigations on metal ion chelation characteristics of the bead‐type copolymers revealed that they have very high adsorptivity toward uranyl ions and good chemical resistance under acidic and alkaline media. It was also found that the phosphono group‐containing copolymer beads are effective adsorbents for other heavy metal ions such as Pb2+, Hg2+, Cd2+, and Cu2+.
Isocyanate reactions in and with N,N‐dimethylformamide
Authors: Joel Detlef , Müller Petra , Ahl Rosemarie 
Published: April 2003

AbstractSolutions of phenylisocyanate (I) in DMF were stored at different temperatures in the presence of both polyurethane catalysts and 1,3‐diphenylurea (II). The reaction products were determined by HPLC. Beside the hydrolysis of I to II, a significant reaction of I with II to 1,3,5‐triphenylbiuret (III) was observed at 20°C. Above 60°C, I reacted with the solvent to form N,N‐dimethyl‐N′‐phenylformamidine (V). In DMF, III dissociated to I and II already at temperatures >40°C.
Zur vernetzung dünner polymerschichten durch photolyse aromatischer bisazide
Authors: Reinisch Gerhard , Wigant Lothar , Hiller Wolf , Schmolke Rudolf 
Published: April 2003

AbstractDie UV‐Vernetzung in 1 μm‐Schichten aus Polymeren verschiedener Konstitution, die 10 Gew.‐% 4,4′‐Diazidobiphenyl (DABP) enthalten, wird zeitabhängig anhand der reduzierten Schichtdicke nach Lösungsmittelbehandlung verglichen. Für die hohe Vernetzungsgeschwindigkeit von Polyglycidylmethacrylat mit den photolytisch gebildeten Bisnitrenen sind die 1,2‐Epoxypropylgruppen verantwortlich. Der Oxiranring bleibt erhalten (IR‐Spektroskopie). Wahrscheinlicher Reaktionsort ist die exocyclische CH2‐Gruppe (13C‐Festkörper‐NMR‐Spektroskopie).
Investigation of synthesis and light stability of polymeric azo dyes. I. Polymeric urethane‐azo dyes
Authors: Lewandowsky Ekkehart , Mayer Roland , Marx Jörg , Böttcher Horst 
Published: April 2003

AbstractStarting from 10 different 4′‐substituted 4‐[N,N‐dihydroxyethyl]aminoazobenzenes, polymeric urethane‐azo dyes (M̄n 42000–10200) were prepared by reacting those with hexamethylene diisocyanate. The dependence of spectral properties, redox potentials and photofading behaviour on the kind of substitutents was determined and then compared with corresponding monomer and dimer model compounds. Photofading is caused by a photooxidative process. In the sequence of monomeric > dimeric > polymeric azo dyes, light stability decreases due to a diminution in thermal disactivation processes and in a possible intramolecular energy transfer.
Effect of electron radiation on dyed PET and PA 66 substrates
Authors: Clauss Bernd , Weiss Mathias 
Published: April 2003

AbstractPET and PA 66 fabrics were dyed with different disperse dyes under regular conditions. The dyed fabrics were irradiated with 180 kV electron radiation. It was observed that increasing radiation doses led to increasing total color differences dE if compared to the unirradiated materials.These color differences are mainly caused by two types of reactions. First by the reversible formation of dye radicals, which can be reoxidized (in air) to the original dye molecules, and second by the irreversible reaction of dye molecules with the fiber polymer. The latter reaction causes a permanent change of the color of the fabric, which can be kept low with the proper irradiation conditions. The decision whether or not this change can be tolerated depends on the further use of the textile.
Preparation of porous bead cellulose with technical grain size
Authors: Lenfeld Jiří , Peška Jan , S̆tamberg Jiří 
Published: April 2003

AbstractBead cellulose, particle diameter 0.1 – 2.7 mm, was prepared from dispersions of viscose in chlorobenzene by applying the thermal sol‐gel transition. Technical viscose containing modifiers Berol Visco 32, Berol Glyco 1540 and Kordamin V was used. The size of cellulose beads can be controlled by means of the amount of oleic acid in the dispersion medium. The optimal result was reached at 5 – 6 mg oleic acid in 90 ml chlorobenzene.
Hydroformylation of nitrile rubber and its characterization
Authors: Bhattacharjee Susmita , Bhowmick Anil K. , Avasthi B. N. 
Published: April 2003

AbstractSelective homogeneous catalytic hydroformylation of nitrile rubber (NBR) has been carried out in presence of trans‐chlorocarbonylbis(triphenylphosphine)rhodium(I) [trans‐RhCl(CO)(PPh3)3] and hydridocarbonyltris(triphenylphosphine)rhodium(I) [RhH(CO)(PPh3)3] as catalysts. At 363 K, under 5.6 MPa pressure (CO:H2 = 1:1) in presence of 0.43 mmol/l catalyst, the amount of hydroformylation is 25% in the case of trans‐RhCl(CO)(PPh3)2 and 30% in the case of RhH (CO)(PPh3)3 for NBR with 40 mol‐% acrylonitrile. Reaction kinetics suggest that both the reactions are pseudo‐first order with respect to olefinic substrate and catalyst concentration. The rate of the reaction is higher in the case of RhH(CO)(PPh3)3. The characterization of the products by IR and NMR spectroscopy shows the formation of internal aldehyde groups from 1,4‐units and terminal branched aldehyde groups from 1,2‐units of the copolymer. Measurements on intrinsic viscosity [η] and glass transition temperature (Tg) suggest a decrease in [η] and an increase in Tg with the degree of formyl functionalization. Gel formation has been observed at higher degree of hydroformylation.
Synthesis and exchange reactions of polymers containing reactive phthalimide groups
Authors: Mahmoud Amal Ahmed , Shaaban Abd‐El‐Fattah Fadel , Khalil Ahmed Abd‐El‐Salam , Messiha Nagi Naguib 
Published: April 2003

AbstractN‐Methacryloyloxyphthalimide (NMPI) and N‐methacryloyloxytetrabromophthalimide (NMTPI) were prepared by the reaction of methacrylic acid with N‐hydroxy‐phthalimide and N‐hydroxytetrabromophthalimide, respectively. The resulting monomers were polymerized. The reactions of the resulting polymers with hydroxy and amine compounds have been studied.
The elastic constants of moulded polymeric composites
Authors: Jian Nianbao , Zhang Mingqiu , Zeng Hanmin 
Published: April 2003

AbstractThe paper makes an approach to the determination of the five independent elastic constants of uniaxial symmetric material with the ultrasonic immersion technique. Only five ultrasonic wave velocities are required during measurement. The elastic constants of the moulded composites comprised of poly(phenylene sulfide), poly(aryl ether sulfone) with cardo side groups, short carbon fiber and carbon black are measured by using the suggested treatment. The results exhibit a close relationship between the elastic properties and the structure of the materials.
Studies on new non‐shrinking, thermally stable araldite®‐type photopolymers with pendent aryl acryloyl groups. IV. Syntheses and photoreaction of araldite®‐type photoresists with pendent aryl acryloyl groups
Authors: Müller H. , Nuyken O. 
Published: April 2003

AbstractAddition polymers of bisphenol‐A and epichlorohydrin can easily be esterified with aryl acryloyl chlorides to yield photosensitive polymers. The photoresists are curable with UV‐irradiation (λ ≥ 280 nm). FT‐IR measurements indicate that the network formation fonforms to second order kinetics. DSC and TGA measurements were carried out. The glass transition temperature of irradiated material is up to 171oC; the material is thermally stable up to 350oC. Spectral data are given.
Interpenetrating polymer network films as piezodialysis membranes
Authors: Galip Hasan 
Published: April 2003

AbstractIn the present study, interpenetrating polymer network (IPN) membranes were investigated for their potential application as piezodialysis membranes. These IPN membranes are not mosaic membranes. It was found that some of these membranes did show piezodialysis effects. Two of the membranes tested under high pressure gave permeates which were found to be more concentrated in sodium chloride than the initial feed solution, when analyzed by differential refractometry. The permeates from one membrane were double checked by titrating the chloride ion with silver nitrate solution. The results of the titration also indicated a positive effect.
Asymmetric addition of n‐butyllithium to aldehydes by chiral polymers having acetoxybornyl moieties
Authors: Liu Jui‐Hsiang , Kuo Jue‐Cheng 
Published: April 2003

AbstractOptically active (+)‐2‐endo‐acetoxy‐5‐endo‐bornyl methacrylate (ABMA) was prepared from (+)‐camphor. The free‐radical homopolymerization of ABMA and its copolymerization with achiral methyl methacrylate (MMA) or styrene (St) were carried out with 2,2′‐azoisobutyronitrile in benzene. Effects of temperature and reaction time on the copolymerization were discussed. The monomer reactivity ratios (r1, r2) for poly(ABMA‐co‐MMA) and poly(ABMA‐co‐St) as well as Q and e values for the chiral ABMA in the copolymerization systems were evaluated by the Fineman‐Ross method. It was found that the absolute value of the specific rotation of poly(ABMA‐co‐MMA) increased with increasing ABMA unit content. A small deviation from linearity was observed, which suggests that asymmetry is not introduced into the copolymer main chain. Temperature and solvent effects on the specific rotation of the chiral homopolymer and copolymers were investigated. The results suggest that the chiral polymers synthesized in this investigation did not show a strong preference for a particular helical conformation. Applications of the chiral polymers on the asymmetric addition of n‐butyllithium to aldehydes were investigated. The effect of temperature and aldehydes on the asymmetric addition were also discussed.
Untersuchungen zur übermolekularen Struktur in Polybutylenterephthalat/Polycarbonat‐Blends
Authors: Radusch Hans‐Joachim , Androsch René , Vogel Jürgen , Trempler Jörg , Fakirov Stoyko 
Published: April 2003

AbstractZur Charakterisierung der übermolekularen Struktur von schmelzegemischten Polybutylenterephthalat(PBT)/Polycarbonat(PC)‐Blends wurden lichtmikroskopische, rontgenographische und kalorimetrische Untersuchungen durchgeführt. Die polarisationsmikroskopischen Aufnahmen zeigen bis zu einer Konzentration von ca. 20 Gew.‐% PC eine rein sphärolithische Struktur. Bei höheren PC‐Konzentrationen wird eine zweite separate, amorphe Phase sichtbar. Mit der DSC‐Methode wurde eine Verschiebung der Glasübergangstemperatur beider Ausgangskomponenten, eine geringe Schmelzpunkterniedrigung der kristallinen PBT‐Phase und unterschiedliche Kristallisationstemperaturen in Abhängigkeit von der Konzentration der Ausgangskomponenten gemessen. Eine Erniedrigung des Kristallinitätsgrades des PBT und eine Kristallisation des PC, insbesondere bei thermischer Nachbehandlung der Blends, wurde mittels Röntgenbeugung und ergänzender Dichtemessungen nachgewiesen.
Kinetics of the free radical polymerization of dimethyl diallyl ammonium chloride, 5. Kinetic model with persulfate as initiator
Authors: Hahn M. , Jaeger W. 
Published: April 2003

AbstractThe polymerization of dimethyl diallyl ammonium chloride in concentrated aqueous solution with persulfate as an initiator can be described up to high conversion by a kinetic model including

formation of primary radicals by activated initiator decomposition as well as by redox reaction of S2O82− and Cl−,
chain propagation via monomer cation associates and
termination by combination of cyclized polymer radicals between each other or with chlorine atoms.
A kinetic expression for the rate of polymerization is presented; rate constants and model parameters have been determined.
Polymerization of acrylamide by electrolytically generated Ce(IV)‐organic acid redox systems
Authors: Saraç A. Sezai , Basak Hüseyin , Soydan A. Bahattin , Akar Ahmet 
Published: April 2003

AbstractCe(IV) salt‐malonic acid or citric acid initiator systems were used for the polymerization of acrylamide in the presence of electrolysis. This allowed Ce(III) to be converted to Ce(IV) during polymerization. Graphite, silver, chromium/nickel, lead, platinum and stainless‐steel electrodes were used. The highest polymerization yield was obtained with a stainless‐steel electrode.
Synthesis of a poly(terephthaloylphosphine)
Authors: Banerjee S. , Palit S. K. , Rahman S. , Maiti S. 
Published: April 2003

AbstractPoly(phenylphosphinediylterephthaloyl), a novel phosphorus‐containing polymer, was synthesized by low‐temperature solution polycondensation of dilithio(phenyl)‐phosphine with terephthaloyl chloride. The resulting polymer is soluble in polar aprotic solvents, having inherent viscosity of 19 ml/g in DMF at 30°C. The polymer was characterized by elemental analysis, IR and 1H‐NMR spectroscopy. TGA data show that the polymer is stable up to 250°C in air. The polymer was found to be self‐extinguishing.
Extension of the measuring range in size exclusion chromatography to higher molar mass by use of a light scattering detector
Authors: Lederer Klaus , Höllwarth Peter 
Published: April 2003

AbstractA new method for the extension of the measuring range of size exclusion chromatography coupled with light scattering (SEC/LALLS) to higher molar mass is presented. This method uses the fact that the light scattering signal can often be detected already at considerable smaller values of the elution volume (i. e. higher values of molar mass) than the concentration signal; furthermore, it takes into account the peak broadening effect in SEC. This procedure is tested for the case of a logarithmic normal distribution and a most probable distribution of molar mass. In the case of polypropylene with a logarithmic normal distribution (M̄w = 420 000, M̄n = 99 000), the range of molar mass covered by SEC/LALLS can be extended by a factor of about 10; with a most probable distribution (M̄n = 100 000), the attainable extension in molar mass assumes a factor of about 2.
Etudes microlithographiques de résines négatives renfermant des unités tétrathiafulvalènes sensibles aux UV
Authors: Giral Louis , Montginoul Claude , Mungroo Aumduth , Sagnes René , Schué François , Guibert Jean‐Charles 
Published: April 2003

AbstractPour résoudre le phéomène de gonflement qui limite la résolution des résines microlithographiques classiques, nous nous sommes intéressés à de nouvelles résines avec lesquelles ce phénomène n'apparait pas. Nous avons retenu pour notre étude les résines R qui renferment en mélange un polymère porteur de radicaux tétrathiafulvalénylcarbonyloxyméthyles et le dibromotétrachloroéthane. Afin de voir l'influence de la nature du radical porteur de l'unité tétrathiafulvalène dans le polymtrè sur les propriétés microlithographiques des résines R, nous nous sommes également intéressés aux polymères renfermant des radicaux tétrathiafulvalénylphénoxymethyles. Les résines R ont été testées sous irradiation UV. Leurs sensibilités dépendent en outre de la valeur de la masse molaire du polymèr.
Photoinitiated surface grafting of synthetic fibers, IV. Applications of textile dyes onto surface‐photografted synthetic fibers
Authors: Feng Zhenguo , Icherenska Magdalena , Rånby Bengt 
Published: April 2003

AbstractHigh‐strength polyethylene (HSPE), polypropylene (PP), poly(ethylene terephthalate) (PET), and poly(vinyl alcohol) (PVA) textile yarns have been surface‐photografted with various functional monomers, such as acrylic acid (AA), acrylamide (AM), glycidyl acrylate (GA) and 4‐vinyl pyridine (VP), by means of the continuous presoaking process developed. The dyeing of these surface‐modified yarns with various textile dyes has been investigated. In general, considerable improvements of dyeability have been observed. The dye adsorption of the surface‐photografted fibers is influenced by many factors, such as type of fiber, amount and properties of the functional monomer grafted on the surface of the fibers, type of textile dye, etc. The fibers surface‐grafted with a monomer containing basic groups, such as acrylamide and 4‐vinyl pyridine, are efficiently dyed with an acid dye. Conversely, a fiber surface‐grafted with acidic functional monomer is easily dyed to deep shades with basic dyes. The dye adsorption increases monotonically with increasing grafting measured in ESCA spectra as relative intensities of relevant lines. The ungrafted HSPE, PP and PET fibers can be dyed to some extent with certain dyes. In the present work, the dye adsorption increased by 3.4 times for HSPE fiber grafted with GA and dyed with the metal complex dye IO, by 7.9 times for PP fiber grafted with AA and dyed with the basic dye MB, by 6.1 times for PET with AM and with the direct dye SL, and by about 15.3 times for PVA with VP and with the acid dye TE.
Study on the thermal behaviour of copolymers of acrylonitrile with halogenated carboxylic acids
Authors: Li Pei Ren , Jia Wei Dong , Liu Bai Jian 
Published: April 2003

AbstractThe thermal stability of AN copolymers was studied by DSC technique in order to get information on the influence of comonomers containing halogenated carboxylic acid on the stabilization of PAN. It is shown that the activation energy of cyclization is reduced in the case of the copolymer with bromoacrylic acid (BrAA, 86.2 kJ/mol) compared with chloroacrylic acid (ClAA, 158 kJ/mol), acrylic acid (AA, 128 kJ/mol) and itaconic acid (IA, 102 kJ/mol). Copolymer AN/BrAA permits the stabilization at higher temperature than AN/IA and AN/AA, helping to shorten the stabilization time. It is proved that comonomer ClAA is not superior to BrAA in the effectiveness of thermal stabilization. The mechanism of the cyclization reaction of AN copolymer containing halogenated carboxylic acid is discussed.
Dynamische kontaktwinkelhysterese an oberflächen von siliconcopolyestern
Authors: Grasnick Gerd , Kamusewitz Helmut , Zimmermann Heinz , Paul Dieter 
Published: April 2003

AbstractSiliconcopolyester wurden als Copolymere oder als Mischung mit Phenyltrichlorsilan‐Hydrolysat hergestellt und aus der Lijsung zu Folien geformt. Durch Messung der dynamischen Kontaktwinkelhysterese wurde die für eine Diffusion von Gasen bei der Gastrennung relevante Phasenverteilung an der Oberfläche dieser Membranen untersucht. Sowohl in Copolymeren als auch in Mischungen wird die Oberfläche durch in Domänen aggregiertes Siloxan bestimmt.
Synthesis of phosphorus‐containing polymers with potential bioactivity
Authors: Trendafilova‐Gercheva D. , Troev K. , Georgieva M. , Vassileva V. 
Published: April 2003

AbstractPhosphorylation of poly(N‐vinyl pyrrolidone‐co‐vinyl amine) and poly(N‐vinyl pyrrolidone‐co‐glycidylcrotonateSystematic name: (2,3‐Epoxypropyl)crotonate.
) is realized by Atherton‐Todd and Fields‐Kabachnik reactions and by the means of direct interaction with phosphorus trichloride and phosphorus trichloride oxide. The composition and structure of the isolated final products was proved by NMR (1H and 31P), IR spectroscopy and elemental analysis.
Studies on new non‐shrinking, thermally stable araldite®‐type photopolymers with pendent aryl acryloyl groups. 5. Partially fluorinated photopolymers
Authors: Nuyken Oskar , Spiegel Sabine , Budde Klaus , Quella Ferdinand 
Published: April 2003

AbstractSeveral partially fluorinated polymers with photosensitive groups have been synthesized and characterized. Their photocuring reaction was studied in detail. The effect of structural units on the dielectric properties and the glass transition temperature was of special interest. Therefore, van Krevelen's increment methods were applied to these novel polymers. New increments for CF2‐, CF3‐ and C6F5‐units have been calculated.
Polyesters with 1.4:3.6‐dianhydrosorbitol as polymeric plasticizers for PVC
Authors: Braun D. , Bergmann M. 
Published: April 2003

AbstractSaturated aliphatic polyesters with 1.4:3.6‐dianhydrosorbitol units were mixed with poly(vinylchloride) (PVC). The mechanical properties of these mixtures were examined by differential scanning calorimetry, stress‐strain experiments, and torsion pendulum measurements. Polyesters containing more than four methylene groups in the acid component are compatible with PVC. These polyesters can serve as plasticizers for PVC. On the contrary, mixtures of PVC with poly(1.4:3.6‐dianhydrosorbitol adipate) are incompatible; in this case, at any blend composition, the two glass transition temperatures of the pure components are observed.
Adsorption of organic species by a cyclodextrin epichlorohydrin network polymer
Authors: Kiji Jitsuo , Konishi Hisatoshi , Okano Tamon , Terashima Takashi , Motomura Koji 
Published: April 2003

AbstractThe adsorption of 4‐methylbiphenyl, sodium dodecylbenzenesulfonate (NaDBS), and phenol on a β‐cyclodextrin epichlorohydrin network polymers at 25°C has been studied. The isotherm of 4‐methylbiphenyl fits well with the Freundlich equation at a concentration range from 10−5 to 10−4 mol/l. The isotherms of NaDBS and phenol deviate from a straight line in the investigated concentration range.
Study of three and four component intermacromolecular complexes involving acrylic copolymers, metal ions, and non‐ionic polymers
Authors: Chatterjee S. K. , Khan A. M. , Ghosh S. 
Published: April 2003

AbstractPoly(methacrylic acid‐co‐methacrylamide) and poly(acrylic acid‐co‐acrylamide) have been synthesized and characterized by known methods. The respective comonomer units of the two copolymers enter into complex formation through hydrogen bonding and ion‐dipole interactions. The unreacted units in the intercopolymer complex also interact with homopolymers such as poly(N‐vinylpyrrolidone) and poly(oxyethylene) as well as transition metal ions to form three and four component intermacromolecular complexes. Formation of these complexes could be shown through several experimental techniques, e.g. viscometry, conductometry, potentiometry, IR and UV spectrophotometry.