bluuebunny/crossref_metadata_2025 huggingface dataset:
Graft copolymerization of anhydro sugar derivatives from macromolecular halides
Authors: Uryu Toshiyuki , Hagino Arata , Terui Keiko , Matsuzaki Kei
Published: April 2003

Cationic graft copolymerizations of bicyclic acetals, 1,6‐anhydro‐2,3,4‐tri‐O‐benzyl‐β‐D‐glucopyranose (LGTBE) and 1,6‐anhydro‐2,3,4‐tri‐O‐methyl‐β‐D‐glucopyranose (LGTME), were investigated with macromolecular carbenium ions formed from polymers that contain reactive halogens. Macromolecular complex catalysts formed from chlorosulfonated polyethylene or poly(isoprene‐co‐chloromethylstyrene) by the action of phosphorus pentafluoride yielded graft copolymers with low proportions (0.6–16%) of poly(LGTBE) or poly(LGTBE‐co‐epichlorohydrin) branchings. It was found that macromolecular complex catalysts formed from poly(styrene‐co‐fluoromethylstyrene) or poly(methyl methacrylate‐co‐fluoromethylstyrene) by the action of boron trifluoride etherate give graft copolymers with high proportions (up to 80%) of poly(LGTBE) or poly(LGTME) branchings. In addition, the model reactions for the graft copolymerization of LGTBE were examined with organic halide‐PF5, organic halide‐AgPF6, and organic fluoride‐BF3·OEt2 catalytic systems, of which the last two indicate that the polymerization is effected by a carbenium ion mechanism.
Polymer adsorption on platinum: Surface coverage determination using iodide‐125
Authors: Ellis Tamir M. , Van De Mark Michael R.
Published: April 2003

Adsorption of iodide‐125, a γ emitter, was used as a quantitative methodology for polymer adsorption surface coverage analysis. Adsorption of I‐125 on clean platinum produced surface elemental ratios of I:Pt of 1:4. The technique was applied to the adsorption of polyethylene glycol terephthalate from trifluoroacetic acid on platinum flags with a 2‐cm2 surface area. This polymer adsorption is approximated by a logarithmic relationship similar to the Temkin isotherm. Polymer coverage attained up to 99.6% of the surface.
Vinyl polymerization. 403. Polymerization of vinyl monomer initiated with sodium poly‐p‐vinylphenolate
Authors: Ouchi Tatsuro , Inamura Masaharu , Kobayashi Akinobu , Imoto Minoru
Published: April 2003

The polymerization of vinyl monomer initiated by poly‐p‐vinylphenol (PVPh) in NaOH aqueous solution was carried out at 85°C with shaking. Methyl methacrylate (MMA) was polymerized, whereas styrene and acrylonitrile were not. PVPh, which is dissociated into phenolate form (PVPh−Na+) in NaOH aqueous solution, was effective for the polymerization. The effects of the amounts of MMA, PVPh, NaOH, and H2O on the conversion of MMA were studied. The rate of polymerization of MMA increased with an increase in the molecular weight of PVPh‐Na. The overall activation energy was estimated as 54 kJ mol−1. The polymerization proceeded through a radical mechanism. The addition of tetra‐n‐butylammonium bromide increased the rate of polymerization.
Molecular weight control in polycondensation of hydroxyl diesters with hexamethylenediamine by polymer matrices
Authors: Ogata Naoya , Sanui Kohei , Tanaka Hozumi , Matsuo Hajime , Iwaki Fusako
Published: April 2003

Polycondensation reactions of hydroxyl diesters such as dimethyl tartrate (DMT) and diethyl mucate (DEM) with hexamethylenediamine (HMD) were carried out in the presence of poly(vinyl pyridine) (P‐VPy) and its copolymers with styrene of different compositions as matrix polymers in order to investigate the difference in interaction forces with monomers or the resulting polyamides owing to hydrogen bonding. It was found that matrix effects of poly(4‐vinyl pyridine) (P‐4VPy) on the rate enhancement and solution viscosity of the resulting polyamide became more pronounced with decreasing solvent polarity. This result suggests that the matrix effects of P‐4VPy on polycondensation are due to hydrogen bonding interactions between hydroxyl diesters and P‐4VPy. The addition of P‐4VPy increased the molecular weight of the resulting polyamide to a higher extent than poly(2‐vinyl pyridine) (P‐2VPy), and the molecular weight of the resulting polyamide could be controlled according to the molecular weight of P‐4VPy. Copolymer composition of 4‐vinyl pyridine–styrene (4VPy/St) copolymers as matrix polymers also affected the molecular weight of the polyamide, which increased with increasing P‐4VPy unit contents in the copolymers.
Photoreduction of viologen‐containing vinyl polymers by 2‐propanol
Authors: Furue M. , Yamanaka S. , Phat L. , Nozakura S.
Published: April 2003

In order to study the role of viologen‐containing vinyl polymers in light energy conversion systems, the photoreduction of the polymer by 2‐propanol and the properties of the reduced polymer were studied in comparison with methylviologen. There were marked polymer effects in the initial rate of photoreduction as well as in the absorption spectra of the photoreduced species. Both effects were interpreted in terms of the local concentration effect of viologen units in the photoreduction step. The spectral difference was found to be due to the dimeric association of the reduced viologen units on the polymer.
Plasma polymerization. V. A systematic investigation of the inductively coupled RF plasma polymerization of the isomeric tetrafluorobenzenes
Authors: Clark D. T. , Abrahman M. Z.
Published: April 2003

A systematic investigation has been made of the composition, gross structural features, and rates of deposition of plasma polymer films produced from the excitation of inductively coupled RF plasmas in the isomeric tetrafluorobenzenes. ESCA data reveal that the dominant reaction involves rearrangement such that under a wide variety of experimental conditions the composition of the crosslinked products remains essentially the same as that of the starting material. Small differences in rates of deposition are observed for the different isomers, and theoretical SCF MO studies at the MNDO level provides a basis for discussion of the experimental data.
Study of photopolymers. XVI. Novel syntheses of the polymers with azidonitrobenzoyl groups and their photochemical and thermochemical reactions
Authors: Nishikubo T. , Iizawa T. , Imagawa I. , Kobayashi K.
Published: April 2003

Poly‐2‐(2‐azido‐5‐nitrobenzoyloxy)ethylmethacrylate (P‐II‐A) and poly‐2‐(4‐azido‐3‐nitrobenzoyloxy)ethylmethacrylate (P‐II‐B) were synthesized from the reactions of 2‐hydroxyethylmethacrylate with 2‐chloro‐5‐nitrobenzoic acid and 4‐chloro‐3‐nitrobenzoic acid, respectively, by substitution reactions of sodium azide with the corresponding chloronitrobenzoyl group. In addition, the degradation reaction of the 2‐azido‐5‐nitrobenzoyl group in P‐II‐A and the transformation of the 4‐azido‐3‐nitrobenzoyl group to 5‐carboxylbenzofurazane‐1‐oxide ring in P‐II‐B by irradiation with ultraviolet (UV) light or by heating were investigated in detail. In the photochemical reaction the reaction of the azide group in P‐II‐A was affected by the presence of a spacer in the polymer chain. Moreover, in the thermochemical reaction the rates of the reactions of azide groups in P‐II‐A and P‐II‐B were controlled by the facility of molecular motion and the conformation of polymer chains.
Cationic polymerizations by aromatic initiating systems. III. Model reactions for initiation and termination using the t‐BuCl/ϕ3Al and Clt‐R‐Clt/ϕ3Al systems
Authors: Kennedy Joseph P. , Chung David Y. L. , Reibel Leonard C.
Published: April 2003

Preparatory for the synthesis of terminally functional polyisobutylenes carrying one or two phenyl end groups, model experiments have been carried out using novel tert‐butyl chloride/triphenylaluminum and 2,6‐dichloro‐2,6‐dimethylheptane/triphenylaluminum initiating systems. As anticipated, t‐BuCl was phenylated by ø3Al and the product is tert‐butylbenzene. The reaction is extremely rapid and temperature has little effect on it in the 0 to −60°C range. The interaction between the 2,6‐dichloro‐2,6‐dimethylheptane and ø3Al was found to be complicated by a proximity effect which leads to proton elimination in addition to phenylation. The formation of the desired diterminally phenylated product is not quanititative even at −60°C.
Kinetics of polymerization of acrylonitrile initiated by acidic permanganate/thioacetamide redox system
Authors: Samal Rajani K. , Nayak M. C. , Suryanarayan G. V. , Panda G. , Das D. P.
Published: April 2003

The kinetics of vinyl polymerization of acrylonitrile (AN) initiated by an acidic permanganate/thioacetamide (TAm) redox system have been investigated in aqueous media at 30 ± 0.2°C in nitrogen, and the rate of polymerization measured. The effect of additives like organic solvents, neutral electrolytes, and complexing agents on the rate have been assessed. Based on the experimental results, a suitable reaction scheme involving initiation by organic free radicals generated by the interaction of Mn(IV) with protonated thioacetamide and termination by Mn(III) has been suggested. Various rate and energy parameters have been evaluated.
Aromatic polyamides. I. Synthesis and characterization of some aromatic polyamides and their model diamides
Authors: Khanna Y. P. , Pearce E. M. , Forman B. D. , Bini D. A.
Published: April 2003

The synthesis of some wholly aromatic polyamides based on unsubstituted and chloro‐ and nitro‐substituted diamines by low temperature solution polymerization is described. Poly(1,3‐phenylene isophthalamide) and poly(chloro‐2,4‐phenylene isophthalamide) were selected for further investigation. To study the two polyamides on a systematic basis their model diamides were synthesized. These materials were characterized with respect to chemical structure and purity by elemental analysis, infrared (IR), and nuclear magnetic resonance (NMR) spectroscopic techniques. The usefulness of the model compounds in the interpretation of the polymer spectra is also demonstrated.
Aromatic polyamides. II. Thermal degradation of some aromatic polyamides and their model diamides
Authors: Khanna Y. P. , Pearce E. M. , Smith J. S. , Burkitt D. T. , Njuguna H. , Hindenlang D. M. , Forman B. D.
Published: April 2003

Thermal degradation behavior of poly(1,3‐phenylene isophthalamide) and poly(chloro‐2,4‐phenylene isophthalamide) was investigated with the aid of some appropriate model compounds. The pyrolysis products of these materials were identified by gas chromatography (GC), gas chromatography/Fourier transform infrared spectroscopy (GC/FT‐IR), and gas chromatography/mass spectrometry (GC/MS). The residual chars were characterized by IR spectroscopy. Thermogravimetric analysis (TGA) was applied to study the effect of end‐group concentration on the degradation characteristics of the two polyamides. Kinetic parameters that describe the thermal degradation of the polyamides were also evaluated by TGA. The results of this investigation suggest that the thermal decomposition of these aromatic polyamides involves homolytic as well as hydrolytic cleavages of the amide units.
Synthesis and properties of poly(dimethylxylylenylamides)
Authors: Rajendran G. P. , Mahadevan V , Srinivasan M.
Published: April 2003

Poly(dimethylxylylenylamides) were synthesized from six different diphenylenediamenes and two dimethyl‐substituted xylylenyldiacid chlorides by solution polycondensation at low temperature. The model compound 2,5‐demethyl1,4‐benzediacetanilide was synthesized and characterized by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopy. The polyamides were characterized by IR and viscosity measurements. Some of the polyamides showed crystalline behavior in the x‐ray diffractograms. The polyamdes have decomposition temperatures in the range 370–310°C in air and are soluble in all amide solvents. The effects of subsituents on crystallinity, thermal stability, and solubility of the polymides are also discussed.
Catalysis of α,β‐elimination of serine by pyridoxal phosphate–metal‐ion‐quaternized poly(4‐vinyl pyridine) system. A serine dehydratase model
Authors: Nakano Hidehiko , Nishioka Masahiro , Sangen Osamu , Yamamoto Yoshitake
Published: April 2003

The effect of quaternized poly(4‐vinyl pyridine)(QPVP) on the α,β‐elimination of series catalyzed to pyridoxall (PL) or pyridoxal phosphate (PLP) and metla ions was investigated. In PLP‐Al3+ and PLP‐Fe3+ systems QPVP showed simulation of about forefold; this stimulation was reduced in the presence of 0.5 M KCI. The catalytic activities of PL‐Al3+ and PL‐Fe3+ were lower compared to the corresponding PLP systems; stimulation by QPVP was also seen, through the extent of stimulation was smaller. The contribution of the electrostatic force between the polymer and the metal complex of the Schiff base was suggested to account for the stimulation. The pyridine moiety on the partialy quaternized PVP did not seen toparticpate in the catalysis. In PLP‐Cu2+, PL‐Cu2+, and PLP‐VO2+ systems, however, QPVP showed marked inhibition. This inhibition by QPVP was also mitigated in the presence of 0.5 M KCl.
Plasma polymerization of tetrafluoroethylene. III. Reproducibility and effects of substrate and reactor materials
Authors: Masuoka Toshio , Yasuda H.
Published: April 2003

Plasma polylmerization occurs in plasmas surrounded by surfaces and polymer formation is one of the complicated interactions that take place between active species and molecules which constitute surfaces and gas phases. Effects of reactor wall, substrate materials, flow rate, and discharge power on polymer formation, and properties of polymer deposits were investigated by ESCA, IR (infrared) spectroscopy, and the measurement of system pressure. The effect of surface is important at the initial stage of plasma polymerization which can be easily detected by the system pressure change; however, integrated properties such as IR spectroscopy and the deposition rate show the effect in a less pronounced manner. ESCA, which reflects the properties of surface (approximately 20 A˚ in depth), showed the effect of surface in an even less sensitive manner. The amount and properties (including the effects of surfaces) are dependent on plasma polymerization parameter W/FM(W, wattage; F, volume flow rate; and M, molecualar weight of monomer) and the location of deposition within a reactor. IR and ESCA data clearly showed the dependence of polymer properties on W/FM; i.e., increase of W and decrease of M to be equivalent. When all these factors were kept under control, the reproducibility of plasma polymerization was found to be excellent.
Extinction of diffusion flames adjacent to flat surfaces of burning polymers
Authors: Sohrab S. H. , Williams F. A.
Published: April 2003

Extinction of the diffusion flames in the stagnation‐point flow above the commercial polymers, poly(methyl methacrylate), polyoxymethylene (two types), polyethylene (three types), and polystyrene, is studied. The extinction data are used in a theory developed to obtain overall rate parameters for gas‐phase combustion of these fuels. Calculated overall rate parameters are corrected for surface heat loss by radiation. It is found that radiation corrections are most significant for polyethylene and polystyrene, in part because of their somewhat higher surface temperatures. Surface regression rates and corresponding surface temperatures are measured to aid in the radiation correction. The results are also used in an Arrhenius‐type rate expression to obtain overall activation energies for the thermal degradation of these polymers for comparison with the literature. Effects of surface losses on flame extinction are discussed.
Kinetics and mechanism of urethane formation catalyzed by organotin compounds. II. The reaction of phenyl isocyanate with methanol in DMF and cyclohexane under the action of dibutyltin diacetate
Authors: Van Der Weij Frederik Willem
Published: April 2003

The kinetics of the dibutyltin diacetate (DBTDA)‐catalyzed reaction of phenyl isocyanate with methanol in DMF and cyclohexane have been studied by monitoring the rate of change of the absorbance of the reaction mixture at 281.6 and 280.9 nm, respectively. Our results indicate that the mechanism of the reaction is independent of the nature of the (inert) solvent. The subsequent reaction steps are (i) complexation of methanol to DBTDA, (ii) dissociation of the complex into a proton and an anion of composition [(n‐C4H9)2Sn(OCOCH3)2(OCH3)]−, (iii) insertion of the isocyanate into the tin—alkoxy bond (the rate‐determining step), and (iv) methanolysis of the thus‐formed urethane precursor with simultaneous regeneration of the anion. The rate of the catalyzed reaction increases on goin from coordinating to noncoordinating solvents. The following sequence in order of increasing rate constant was observed: DMF < dibutyl ether < cyclohexane. This is because in coordinating solvents, DBTDA and methanol, apart from forming a complex with each other, also form complexes with the solvent.
C3 cyclopolymerization. IV.1 Cationic polymerization of 1,3‐bis(4‐vinylnaphthyl) propane and the polymer structure yielded
Authors: Nishimura J. , Furukawa M. , Yamashita S. , Inazu T. , Yoshino T.
Published: April 2003

The compound 1,3‐bis(4‐vinylnaphthyl)propane was prepared by a convenient dehydration of 1,3‐bis[4‐(1‐hydroxyethyl)naphthyl]propane. The structure was confirmed by nuclear magnetic resonance (NMR) spectroscopy. The monomer was polymerized by antimony pentachloride, tin tetrachloride, titanium tetrachloride, or boron trifluoride etherate at 0°C in toluene, 1,2‐dichloroethane, or a mixed solvent of 1,2‐dichloroethane and nitromethane. Most of runs except for antimony pentachloride–catalyzed ones gave mainly benzene‐soluble polymers. The structures of the polymers were studied by several spectroscopic methods. Comparison of NMR and fluorescence spectroscopic data of the polymers with those of syn‐and anti‐[3.3](1,4)napthalenophane was especially valuable in leading to the conclusion that they were cyclopolymers containing predominantly syn‐[3.3]‐(1,4)naphthalenophane units in the main chain.
The preparation and reactions of polymeric azides. II. The preparation and reactions of various polymeric azides
Authors: Cohen H. L.
Published: April 2003

Polymeric haloethyl acrylates, methacrylates, and methacrylamides, poly(vinyl chloride), poly‐(epichlorohydrin), and halohydrins prepared from poly(glycidyl methacrylate), poly(butadiene), and poly(pentenamer) were converted to the corresponding azides. These azides reacted with a variety of acetylenic and olefinic derivatives to give, in most cases, good conversions to the corresponding triazole derivatives.
Preparation and properties of aromatic polyamide‐esters from aminophenols and aromatic diacid chlorides
Authors: Imai Yoshio , Abe Shigemitsu , Ueda Mitsuru
Published: April 2003

Aromatic polyamide‐esters of moderately high molecular weight were prepared from various combinations of three aminophenols (m‐ and p‐aminophenol, and 4‐(4′‐aminophenoxy) phenol) and two aromatic diacid chlorides (isophthaloyl and terephthaloyl) by interfacial polycondensation in a cyclohexanone/water system and two‐phase polycondensation in a dichloromethane/water system with phase‐transfer catalysts. The solution polycondensation in dichloromethane/N,N‐dimethylacetamide was also successful for the production of high‐molecular‐weight polymers. The solubility of the aromatic polyamide‐esters varied markedly with polymer structure. Except for two polyamide‐esters derived from terephthaloyl chloride, all the other polymers were almost amorphous. These polymers had glass transition temperatures at around 200°C and showed 10% weight losses at about 400°C in both air and nitrogen atmospheres.
Buoyancy and relative flow rates in ultrcentrifugation
Authors: Elmgren Hans
Published: April 2003

It is shown that the buoyancy factor (1–v̄ρ), used in sedimentation studies, is the product of the true buoyancy factor (1–v̄ρ0) and a backflow factor. In two‐component systems, the latter is the volume fraction (1–Φ) of the solvent. The corresponding factor for the case of multicomponent systems is also given.
Reverse osmosis separation of alkaline metal ions through hydrophobic membranes
Authors: Igawa Manabu , Nakamura Yoshinori , Takahashi Kōsei , Tanaka Masao , Senō Manabu
Published: April 2003

A very thin hydrophobic membrane separated alkaline metal ions under a pressure gradient. The membrane was prepared by coating polystyrene or other polymers on a Teflon membrane filter. The permeabilities of alkaline metal ions under a pressure gradient decreased with increasing ion radius, while the diffusion fluxes in a dialysis experiment increased with increasing ion radius. The selectivity was enlarged in the mixed salts solution of a low concentration at a high pressure.
Intramolecular charge transfer complexes. 16. Copolymers of N,N‐dimethyl‐p‐aminobenzyl methacrylate with acryloyl‐ and methacryloyl‐β‐hydroxyethyl‐3,5‐dinitrobenzoate
Authors: Simionescu C. I. , Percec V. , Natansohn A.
Published: April 2003

A new electronodonor monomer, N,N‐dimethyl‐p‐aminobenzyl methacrylate (DMABM), was synthesized and radical copolymerized with two electronoacceptor monomers, acryloyl‐ (DNBA) and methacryloyl‐(DNBM) β‐hydroxyethyl‐3,5‐dinitrobenzoate, in order to obtain intramolecular charge‐transfer‐complex copolymers. Also, the small‐molecular models of poly(DMABM), poly(DNBA), and poly(DNBM), the respective acetates, were synthesized and used to measure the values of ionization potential Ip of the donor and the electronic affinity Ea of the acceptor. They are Ip = 7.15 eV and Ea = 1.41 eV. The lower value of Ip as compared with that of carbazole derivatives is taken as evidence of a nonterminal mechanism of copolymerization. Also, from the 1H‐NMR and electronic spectra, the intramolecular complexation is discussed in terms of total transfer of the electron from donor to acceptor structural units.
Polyureas from carbon dioxide and diamines by means of triphenyl phosphite and pyridine hydrochloride
Authors: Higashi Fukuji , Murakami Tomoyoshi , Taguchi Yuji
Published: April 2003

The reaction of carbon dioxide with aniline using triphenyl phosphite in pyridine is greatly facilitated by the addition of hydrochlorides of tertiary amines such as pyridine and triethylamine, and has been successfully applied to the preparation of polyureas of high molecular weight from carbon dioxide and aromatic diamines. The presence of a catalytic amount of pyridine hydrochloride significantly increased the inherent viscosity of the resulting polymers, the highest value being obtained with about an equivalent of the chloride. Optimal temperatures and pressures varied with diamines used, and were 60–80°C and 40–50 atm of carbon dioxide. The polycondensation reaction was also affected by the solvent compositions of pyridine and N‐methylpyrrolidone, its optimum being dependent on diamines used.
Pyrolysis mass spectrometry of terephthalate polyesters using negative ionization
Authors: Adams Robert E.
Published: April 2003

The usual method of studying thermal degradation mechanisms of polymers in vacuo is to use electron ionization pyrolysis mass spectrometry. This can lead to mass spectral fragmentation from the 70 eV electrons used. Low energy electrons (10–15 eV) produce a low abundance of positive ions. However, if a molecule is prone to capture a thermal energy electron, then negative ions are produced in high abundance. This report describes the negative ion pyrolysis mass spectrometry of polyethylene terephthalate and polybutylene terephthalate.
Phthalocyanine polymers. I. Poly[2,2′‐(4,4′,4″‐,4‴‐metal phthalocyanino)‐5,5′‐bibenzimidazoles] as new high temperature resistant polymers
Authors: Achar B. N. , Fohlen G. M. , Parker J. A.
Published: April 2003

A novel class of poly(metal phthalocyanino) benzimidazoles were prepared by the condensation reaction between metal (Cu, Co, and Zn), 4,4′,4″,4‴‐tetracarboxyphthalocyanine, and 3,3′‐diaminobenzidine. The reaction was investigated by melt and solution condensation methods. These polymers showed excellent thermal and thermooxidative stability and are noteworthy for their high char yield (86–90%) at 800°C in an anerobic atmosphere. Elemental analyses, spectra, and TGA studies were used to characterize these materials. Isothermal gravimetric analyses were carried out to determine their long‐term thermal stability.
Aliphatic polyesters. III. Molecular weight and molecular weight distribution in alcohol‐initiated polymerizations of ϵ‐caprolactone
Authors: Schindler A. , Hibionada Y. M. , Pitt C. G.
Published: April 2003

The effect of initiation of ϵ‐caprolactone polymerization with mono‐ and polyfunctional alcohols was investigated. The resulting linear and starshaped polymers were characterized by measurement of the molecular weight and molecular weight distribution. The polymerizations were characterized by (1) rapid initiation, (2) invariance of the number of growing chains corresponding to the amount of initiator, and (3) a dominant role played by ester interchange reactions.
Conformational and neighboring effects in graft polymerization of acrolein onto imidazole‐containing polymer
Authors: Yamashita Natsuki , Morita Satoshi , Maeshima Toshihisa
Published: April 2003

The graft polymerizations of acrolein (AL) onto an imidazole (Im)‐containing polymer, such as a homopolymer of 4(5)‐vinylimidazole (VIm) and several copolymers of VIm‐methyl vinyl ketone, VIm‐butyl acrylate, and VIm‐2‐ethyl hexyl acrylate, have been kinetically carried out in ethanol‐water mixture at 0°C. The graft polymerization rate Rp and the degree of graft polymerization increased with increasing concentration of water in the solvent. Moreover, the Rp of the copolymer system having the hydrophobic group as the side chain decreased in comparison with the homopolymer system. Polymerizations of AL in the presence of propionamide or poly‐acrylamide (AAm) induced by Im were also kinetically carried out in ethanol‐water mixture. The Rp was also affected by the conformational change of poly‐AAm. These results were discussed by assuming the conformation of the parent polymer in ethanol‐water mixture.
Effects of ligands on the “living” radical polymerization initiated by the aged Cr2+ plus benzoyl peroxide system
Authors: Lee Munam , Ishida Yoshikazu , Minoura Yuji
Published: April 2003

The “living” radical polymerization of methyl methacrylate with the aged Cr2+ plus benzoyl peroxide (BPO) system in the presence of various amines as ligand has been studied in N,N′‐dimethylformamide. Aliphatic amines such as ethylenediamine diminished the rate of polymerization, while dipyridyl (dipy) and o‐phenanthroline (phen) accelerated the polymerization rate as follows: phen > dipy > pyridine ≃ none. Specifically, the rate of polymerization in the presence of phen had a maximum value at [phen]/[Cr2+] = 0.5. The retardation of polymerization by aliphatic amines was explained by the interaction of BPO with free and coordinated amines. The latter result may support the mechanism involving the complexed radical proposed for the living radical polymerization with the aged Cr2+ + BPO system. In the presence of phen the effects of aging period and aging temperature as well as polymerization temperature were studied and the nature of complexed radicals is discussed.
Amphiphilic copolymers of some aromatic vinyl compounds and an electrolytic monomer as potential media for photosensitized electron transfer: Fluorescence quenching by an amphiphilic electron acceptor in aqueous media
Authors: Itoh Yoshihiro , Morishima Yotaro , Nozakura Shun‐Ichi
Published: April 2003

Amphiphilic polymers were prepared by the copolymerization of 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS) and aromatic vinyl compounds such as 9‐vinylphenanthrene (VPh) and 1‐vinylpyrene (VPy) with the expectation that they would serve as potential media for photosensitized electron transfer reactions. AMPS strongly solubilizes the hydrophobic segments into water; i.e., poly(AMPS‐co‐VPh) with VPh mole fraction (fPh) up to about 0.60 and poly(AMPS‐co‐VPy) with VPy mole fraction (fPy) up to about 0.35 were found to be soluble in water. Poly(AMPS‐co‐VPh) in aqueous solution, as compared with that in DMF solution, showed a broad fluorescence spectrum with significant tailing in the longer‐wavelength region along with a decrease in the intensity of the structured, monomer fluorescence band. These phenomena seem to imply the presence of an excimerlike interaction of phenanthryl groups in an aqueous solution through which the fluorescence from excited VPh units may be partly self‐quenched. A considerable enhancement of the fluorescence from sodium 8‐anilino‐1‐naphthalenesulfonate (ANS) caused by hydrophobic interaction of the probe with poly(AMPS‐co‐VPh) in aqueous solution indicated that these copolymers assume micellar structures. The fluorescence of these copolymers in aqueous solutions was quenched by bis(2‐hydroxyethyl)terephthalate (BHET), an amphiphilic quencher, far more effectively than by fumaric acid, a hydrophilic quencher. This tendency is particularly strong for the copolymers with higher content of hydrophobic units. The second‐order rate constants for the quenching of poly(AMPS‐co‐VPh) (fPh = 0.58) by BHET were found to be ca. 3 × 1010 and 1.5 × 109 M−1 s−1 in aqueous and in DMF solution, respectively. The larger value in an aqueous solution is presumably due to an increase of the effective concentration of the amphiphilic quencher around the VPh sequences of the copolymer resulting from hydrophobic interaction.
Synthesis of ion‐exchange membranes by radiation‐induced multiple grafting of methyl α,β,β‐trifluoroacrylate
Authors: Omichi Hideki , Okamoto Jiro
Published: April 2003

Methyl α,β,β‐trifluoroacrylate (MTFA) was grafted onto polymer films with the multiple grafting technique initiated by α‐rays: the yields were similar to those of the single‐step grafting procedure with any irradiation dose. Grafted polymer obtained in the single‐step experiments were distributed mainly near the film surface, whereas graft polymer from the multiple grafting experiments were distributed uniformly in the film at graft yields greater than 20%. The electric resistance of the hydrolyzed multiple graft polymer film in a 2N NaOH solution was much lower than that of one‐step graft film at the same graft yield.
Copolymerization of N‐carboxy Nϵ‐carbobenzoxy L‐lysine anhydride with N‐carboxy β‐benzyl L‐aspartate anhydride in acetonitrile
Authors: Ōya Masanao , Takahashi Tomoko
Published: April 2003

Copolymerization of N‐carboxy Nϵ‐carbobenzoxy L‐lysine anydride with N‐carboxy β‐benzyl L‐aspartate anhydride was initiated with n‐butylamine in acetonitrile. The copolymerization proceeded almost homogeneously except for the initial stage, when the proportion of N‐carboxy anhydride (NCA) in the polymerization mixture varied from 25 to 75 mol %. This was due to the fact that the copolypeptides formed were soluble or highly swollen in the solvent, in contrast to the homopolymerization of NCAs such as Nϵ‐carbobenzoxy L‐lysine NCA and β‐benzyl L‐aspartate NCA in acetonitrile, which proceeds heterogeneously. The compositions of the copolymers obtained were, within experimental error, the same as their monomer feed compositions. The initial rates of copolymerization were almost the same as the rate of homopolymerization of β‐benzyl L‐aspartate NCA, which propagates with a nonhelical polypeptide, but were slower than the rate of homopolymerization of Nϵ‐carbobenzoxy L‐lysine NCA, which propagates with a helical polypeptide.
Synthesis of polysulfohexyl methacrylate with anticoagulant activity
Authors: Chen W. Y. , Xu B. Z. , Feng X. D. , Voong S. T.
Published: April 2003

Sulfohexyl methacrylate and its polymer have been prepared. The anticoagulation activity of this polymer and copolymers with hydroxyethyl methacrylate and acrylamide was compared with that of polyhydroxyethyl methacrylate, polysulfoethyl methacrylate, and heparin. The activated‐carbon microcapsule coated with polysulfohexyl methacrylate showed itself a promising adsorbent.
Exactly alternating silarylene‐siloxane polymers. III. Structure‐property relationships for polymers containing p‐phenylene and p,p′‐diphenyl ether silarylene units
Authors: Dvornic Petar R. , Lenz Robert W.
Published: April 2003

A series of 12 different exactly alternating silarylene‐siloxane polymers was prepared by low temperature condensation polymerization of arylenedisilanol with bisureidosilane monomers. The structural characterization of the polymers was carried out by 1H NMR spectroscopy, 13C NMR spectroscopy, infrared (IR) spectrometry, gel permeation chromatography (GPC). dilute solution viscometry, and differential scanning calorimetry (DSC). Homopolymers and copolymers that contained either or both p‐phenylene and p,p′‐diphenyl ether units in the silarylene group and dimethyl or methylvinyl units in the siloxane group were prepared in high molecular weights.
The chemistry and kinetic behavior of Cu‐Cr‐As/B wood preservatives. IV. Fixation of CCA to wood
Authors: Pizzi A.
Published: April 2003

The kinetic behavior of copper–chromium–arsenic (CCA) wood preservatives in their reaction with wood, lignin, cellulose, and their respective simple model compounds, guaiacol and D(+)‐glucose, has been elucidated. Copper chromatesVI/lignin guaiacyl units and chromiumIII arsenates/lignin guaiacyl units, which are stable and insoluble complexes formed during the reaction, have been characterized. No copper arsenates were formed during the reactions (which were carried out using a CCA of type C). The sequence, nature, and combined effect of the reactions of CCA with wood, lignin, and cellulose are similar to that already described for the “CrO3 alone,”1 Cu/Cr2, and Cr/As3 systems. Rate constants, energies of activation, and Arrhenius equations have been obtained and reported. The distribution of CrVI, CrIII, Asv, and Cu2+ in CCA‐C‐treated wood has been calculated. The results obtained have allowed meaningful comparisons of several commercial CCA formulations.
Polyiodide composition in poly(vinyl acetate)‐iodine‐iodide complex
Authors: Hayashi Sadao , Hirai Toshihiro , Shimomichi Sonoko , Hojo Nobumasa
Published: April 2003

Polyiodide formed by complexation of poly(vinyl acetate) (PVAc) with iodine in the presence of iodide has been investigated by chemical analysis and resonance Raman spectrophotometry. When PVAc films were immersed in iodide‐iodine aqueous solutions which had different ratios of iodide to iodine concentration [I−]/[I2], the complex films exhibited tremendous variations of swelling degree, despite the relatively small change in the amount of bound iodine. From a quantitative chemical analysis, the composition of polyiodide bound to PVAc was found to be 1.01 ± 0.035 in the molar ratio of iodide to iodine irrespective of the composition of the iodide‐iodine aqueous solution ([I−]/[I2] = 2–500). The polyiodide formed in PVAc‐iodine‐iodide complex was therefore inferred to be (I3−)n. Resonance Raman spectra obtained on PVAc‐iodine‐iodide complexes were also identical to those of the benzamide‐iodine complex, in which the polyiodide consists of (I3−)n, consistent with the result from chemical analysis.
Radiation‐initiated emulsion copolymerization of styrene and carboxylic acid monomers
Authors: Egusa Shigenori , Makuuchi Keizo
Published: April 2003

The emulsion Copolymerization of styrene and carboxylic acid monomers such as acrylic, methacrylic, and itaconic acids (AAc, MAAc, IAc) was studied by using 60Co γ‐rays as initiator and sodium do‐decylsulfate as emulsifier. The polymerization behavior of these acid monomers was followed by simultaneous conductometric and potentiometric titrations for a latex sample taken in polymerization. The polymerization rate of these acid monomers increases in the following order of hydrophobicity: IAc < AAc < MAAc; this suggests that their polymerization sites are mainly the surface and/or subsurface regions of latex particles. The copolymerization rate of styrene and acid monomer increases with an increase in the acid monomer content for AAc and MAAc, whereas for IAc the rate decreases. The particle sizes determined by the stopped‐flow method reveal that this variation of copolymerization rate cannot be explained by the number of growing particles and should be attributed to another factor; for instance, the transfer rate of styrene molecules from oil droplets to growing particles.
The complexing of polymetaphosphate anions with calcium cations: A potentiometric (pCa) study
Authors: Packter A. , Doherty W. O. S.
Published: April 2003

Calcium cation complexing by polymetaphosphate anions was studied by direct potentiometric measurements with a calcium‐ion‐sensitive electrode. The moderately stable neutral chelate (Ca2P4O)n is formed in (CaP2O6)n solutions according to the equilibria

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logK12 values for complexing with polyanions of Mav ≃ 1200 and 2500 (at C = 0.0003M) were 5.86 and 6.26, respectively; the K12 values then decreased with increasing polyanion concentration and were reduced by addition of equivalent sodium chloride. The very stable chelate anion (CaP4O)n is then formed in (Na2CaP4O12)n solutions according to the equilibrium

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logK14 values for complexing with polyanions of Mav ≃ 1200 and 2500 (at C = 0.0003M) were 7.48 and 8.08, respectively; these K14 values also decreased with polyanion concentration. A less stable complex anion (CaP6O)n is formed in more concentrated solutions at PO3/Ca ratios > 6.
Kinetics of simultaneous decrystallization and crystallization induced in high‐modulus rayon by bromine water
Authors: Lewin Menachem , Guttmann Hilda , Knoll Arie , Derfler David
Published: April 2003

Studies of the effect of aqueous Br2 solution on the fine structure of cellulose have shown that the accessibility of the cellulose is a complex function of the duration of treatment. Following immersion of rayon‐cellulose in the Br2 solution, its accessibility is observed to increase until a peak is reached, after which the accessibility decreases with time. For higher temperatures and greater concentrations of Br2, a sharper peak and faster rates of increase and decrease of accessibility are obtained. In order to explain this behavior, a mathematical model of the kinetics is postulated involving two opposing first‐order processes occurring simultaneously. One process describes the decrystallization of crystalline regions within the cellulose by opening intermediate linkages due to Van‐der‐Waals forces involved. The second process relates to the crystallization of the less‐ordered regions. The rate constants for these processes are determined by fitting experimental curves to the postulated analytical expression with the aid of a digital computer program. Experiments carried out on high‐modulus rayon showed that for this type of cellulose, the effect described above was very pronounced. From the calculated rate constants, the activation energies of the crystallization and decrystallization reactions were determined. The plots of the rate constants versus 1/T showed that a break occurs at 25°C, corresponding to a second‐order transition point of cellulose. The energies of activation of the crystallization process are in the range of 7–9 and 10–13 kcal/mol in the temperature ranges 10–25 and 25–40°C, respectively. The activation energies of the decrystallization process are 13 and 18–24 kcal/mol in these temperature ranges.
Synthesis, polymerization, and copolymerization of lactam‐substituted styrenes
Authors: Samyn C. , Smets G.
Published: April 2003

Four new substituted styrene derivatives carrying lactam rings (2‐pyrrolidone or 2‐piperidone) in para position have been synthesized, namely 4‐(2‐oxo‐3‐methylene‐pyrrolidinyl)styrene, 4‐(2‐oxo‐3‐methylene‐piperidinyl)styrene, 4‐(p‐styryl)‐2‐pyrrolidone, and 4‐(p‐styryl)‐2‐piperidone. Their homopolymerization and copolymerization with styrene, methyl methacrylate, and acrylic acid have been considered. By ring opening of the side lactam groups, the homopolymers are transformed into the corresponding poly aminocarboxylic acids.
Photoinduced electron transfer from polystyrene pendant tris(2,2′‐bipyridyl)ruthenium (II) complex to methylviologen
Authors: Kaneko Masao , Ochiai Masahisa , Kinosita Kazuhiko , Yamada Akira
Published: April 2003

The characteristics of the photoinduced electron transfer reaction from polystyrene pendant tris(2,2′‐bipyridyl)ruthenium (II) complex [Ru(bpy)] to methylviologen (MV2+) were studied. The rate constant k1 from the excited state of the complex, Ru(bpy), to MV2+ were determined for both the polymeric and monomeric complexes from the lifetime τ of Ru(bpy) and the quenching rate of Ru(bpy) by MV2+. The polymer pendant Ru(bpy) showed three kinds of τ components ranging from 7 to 474 ns, in contrast to the monomeric complex, which showed one component of 350 ns. The k1 values for both complexes were almost the same, on the order of 108 L/mol s. The photoinduced electron transfer from solid‐phase Ru(bpy) to liquid‐phase MV2+ was realized by utilizing the polymer complex, and the solid–liquid interphase reaction system is discussed.
Polymerization of pyrrole by potassium persulfate
Authors: Khulbe K. C. , Mann R. S. , Khulbe C. P.
Published: April 2003

Pyrrole reacted with potassium persulfate in aqueous media to form polymers or “pyrrole blacks.” The structure and molecular weight depend on the initial pyrrole/K2S2O8 ratio. An ESR line due to trapped electrons or free radical ions appeared at g = 2.0036 (width 3.6 G) in all products and its intensity decreased with an increase in initial concentration of potassium persulfate.
Polymerization of aromatic hydrocarbons with sulfur
Authors: Lewis I. C. , Greinke R. A.
Published: April 2003

The polymerization reactions of elemental sulfur with the polynuclear aromatic hydrocarbons pyrene and chrysene were studied. Heating the hydrocarbons with sulfur produces a series of sulfur‐containing oligomers in which the aromatic ring systems remain intact. Polymerization is effected through the dehydrogenative action of sulfur and leads to thermally stable five‐ or six‐membered heterocyclic ring systems. The major loss of sulfur during subsequent heat treatment occurs only at carbonization temperatures above 1000°C.
Polymerization of vinylpyridinium salts. XII. Occurrence of radical polymerization in spontaneous reactions
Authors: Salamone J. C. , Mahmud M. U. , Watterson A. C. , Olson A. P. , Ellis E. J.
Published: April 2003

There has been considerable disagreement regarding the mechanism of the spontaneous polymerization of vinylpyridinium salts in aqueous or acidic solution above 1.0 mol L−1 in monomer concentration. In this report the position of Ringsdorf and co‐workers is substantiated with regard to the existence of a free‐radical reaction, but the kinetic results obtained differ. In particular, it is shown that a lack of spontaneous polymerization below 1.0 mol L−1 is not due to a nonexistence of‐a critical monomer concentration for aggregation, but is instead a kinetic phenomenon of Rp ∼ [M]2.7.
The reduced equation of state and related properties of molten high polymers
Authors: Cho Han Gook , Yoon Sung Chul , Jhon Mu Shik
Published: April 2003

The significant‐structure theory of liquids has been applied to molten amorphous polymers. Expressions of reduced states for these systems are derived for the equation of state and thermodynamic properties such as expansion coefficient, compressibility, internal pressure, and cohesive energy density, and the surface tension. The calculated values are in good agreement with experimental results in comparison with those from other models. In particular, our model predicts the corresponding dependence of the internal pressure better than other models.
Rare‐earth‐metal‐containing polymers. 5. Synthesis, characterization, and fluorescence properties of Eu3+‐polymer complexes containing carboxylbenzoyl and carboxylnaphthoyl ligands
Authors: Ueba Y. , Zhu K. J. , Banks E. , Okamoto Y.
Published: April 2003

Partially 2‐carboxylbenzoyl (1) and 3‐carboxyl‐2‐naphthoyl (2) substituted polystyrene were prepared by the Friedel‐Crafts reaction of polystyrene with corresponding dicarboxylic anhydrides. Europium (III) salts of (1) and (2) and the copolymer of 4‐vinylbenzoyl 2′‐carboxylbenzoate‐di(2‐benzoyl benzoate) and styrene (5) were prepared. Polymer (5) was prepared by the copolymerization of the Eu3+ salt of 4‐vinylbenzoyl 2′‐benzoate and 2‐benzoylbenzoate (ratio 1:2) with styrene. The fluorescence emission intensity was measured on fine powder samples. The intensity of (5) increased linearly as the Eu content increased. However, for the 1 and 2 systems the intensity reached a maximum at a Eu content as small as 0.5 wt% and remained constant when further increases were made. This phenomenon was accounted for by steric hindrance and a decrease in the freedom of bond rotation, which prevent the formation of multiple coordination linkages between Eu3+ and the benzoate groups.
Palladium‐doped polyimides: An X‐ray photoelectron study
Authors: Furstch T. A. , Taylor L. T. , Fritz T. W. , Fortner G. , Khor E.
Published: April 2003

Five polyimide films prepared from 3,3′,4,4′‐benzophenone tetracarboxylic acid'dianhydride (BTDA) and diamines, 4,4′‐oxydianiline (ODA), 3,3′‐diaminobenzophenone (DABP), or 3,3′‐diaminodiphenylcarbinol (DADPC) and doped with Li2PdCl4 (LTP) or Pd[(CH3)2S]2Cl2 (PDS) were selected for a detailed x‐ray photoelectron spectroscopic (XPS) study to determine the oxidation state of palladium and the relative distribution of this and other elements in these films, especially as they relate to electrical resistivity. XPS shows that Pd in the films is present as a mixture of zero and +2 valence states. Films that contain lithium as part of the dopant all show that metal is present as Li+ and Li2O, a fact that may have a bearing on film electrical properties. An Auger electron spectroscopic (AES) or XPS profiling was performed on two of the electrically conductive films. A film doped with PDS reveals a majority of palladium at the surface as Pd(0) and much smaller amounts in film bulk as a mixture of Pd(0) and Pd(II). Film behavior is similar to a metal‐vapor deposited film. An LTP doped film, by contrast, exhibits a homogeneous composition with a mixture of Pd(0) and Pd(II). These studies support others that use chemical etching on the film surfaces. Scanning electron microscopy (SEM) has been used to provide surface evaluations.
Diffusion‐controlled vinyl polymerization. IV. Comparison of theory and experiment
Authors: Soh S. K. , Sundberg D. C.
Published: April 2003

Bulk polymerization data of methyl methacrylate, ethyl methacrylate, ethyl acrylate, n‐propyl acrylate, vinyl acetate, and styrene were compared with the predictions of the theory proposed in the earlier parts of this series (I‐III). This theory of polymerization kinetics uses the concepts of free volume and chain entanglements to describe the relationship between chain mobility and chain length dependent termination reactions. Excellent agreement was found between the predictions of the theory and the polymerization rate and molecular weight data of the six polymerization systems studied. Emphasis was placed on the ability to explain the development of higher order molecular weight averages (M̄w, M̄z, etc.) because they provide the most crucial tests for such a model. No changes were required in the model as it was applied to the different polymerization systems for a variety of reaction conditions. The theory offers a unified understanding of the diverse polymerization behavior displayed by such systems.
Complex formation between poly(ethylene oxide) and alkali picrates
Authors: Dimov D. K. , Panayotov I. M. , Lazarov V. N. , Tsvetanov Ch. B.
Published: April 2003

The interaction of poly(ethylene oxide) with alkali picrates in tetrahydrofuran and dioxane was studied by optical and NMR spectroscopy and conductance measurements. Evidence was found of the formation of two kinds of solvation complex, differing in the nature of the ion pairs involved. A strong anion effect on cation binding to the polyether was demonstrated.
Preparation of water‐soluble photoresist derived from poly(vinyl alcohol)
Authors: Ichimura Kunihiro
Published: April 2003

The reaction of PVA with 2,2‐dialkoxyethoxystyrylpyridinium or quinolinium salts is described. The resultant water‐soluble polymers, which contain small amounts of the styrylpyridinium‐ or quinolinium group, exhibited high photosensitivity. Among the polymers prepared PVA‐bearing 4‐oxystyrylquinolinium group was photoinsolubilized with visible light that corresponded to an argon laser.