bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and characterization of soluble aromatic polyamides from 2,5‐bis(4‐aminophenyl)—3,4‐diphenylthiophene and aromatic diacid chlorides
Authors: Imai Yoshio , Maldar N. N. , Kakimoto Masa‐Aki
Published: April 2003

New soluble aromatic polyamides with inherent viscosities of 1.0–1.7 dL/g were prepared by the low temperature solution polycondensation of 2,5‐bis(4‐aminophenyl)—3,4‐diphenylthiophene, bis(4‐aminophenyl) ether, and aromatic diacid chlorides in N,N‐dimethylacetamide. The polyamides and copolyamides are generally soluble in amide‐type solvents. They have glass transition temperatures in the range of 280–325°C and showed no weight loss below 390°C on thermogravimetry curves in both air and nitrogen atmospheres.
Copolymers of 2‐hydroxyethyl methacrylate and alkyl methacrylates. I. Synthesis and characterization
Authors: Choudhary Manjeet S. , Varma Indra K.
Published: April 2003

Copolymerization of 2‐hydroxyethyl methacrylate (HEMA) with ethyl methacrylate (EMA) and n‐butyl methacrylate (BMA) was carried out in bulk at 70°C ± 1°C using 0.2% benzoyl peroxide as initiator in nitrogen atmosphere. Number average molecular weight (Mn) of the copolymers was determined by dynamic osmometry. Intrinsic viscosity [η] of HEMA‐BMA copolymers was evaluated at 35°C in dimethyl formamide. These copolymers were also characterized by infrared spectroscopy and density measurements. Cohesive energy densities (CED) of these polymers were determined by observing their swelling behavior in different solvents. It was found that a decrease in alkyl methacrylate content resulted in an increase in the CED values of the copolymers.
Synthesis of polyamides from active N,N′‐diacylbis [1,2‐benzisothiazol‐3(2h)‐one]s and 4,4′‐oxydianiline under mild conditions
Authors: Ueda Mitsuru , Mochizuki Amane
Published: April 2003

The aminolysis of 3‐benzoyloxy‐1,2‐benzisothiazole and N‐benzoyl[1,2‐benzisothiazol‐3(2H)‐one] derived from 1,2‐benzisothiazol‐3‐ol was studied in model systems and was found to give good yields of N‐substituted benzamides at room temperature. Solution polycondensation of new bisamides, N,N′‐isophthaloyldi[1,2‐benzisothiazol‐3(2H)‐one], and N,N′‐adipoyldi[1,2‐benzisothiazol‐3(2H)‐one], proceeded slowly to give polyamides with moderate molecular weights. The chloroform–triethylamine · hydrochloride system was the best polycondensation medium compared with some polar aprotic solvents for the formation of higher‐molecular‐weight polyamides.
Kinetics and mechanism for the phase transfer catalyzed cycloaddition of dichlorocarbene to cis‐1,4‐polybutadiene
Authors: Huvard Gary S. , Nicholas Paul P. , Horne Samuel E.
Published: April 2003

The kinetics for the cycloaddition of dichlorocarbene to cis‐1,4‐polybutadiene (BR) have been examined for aqueous and solid sodium hydroxide–chloroform mixtures containing 350 molecular weight α‐methyl‐ω‐hydroxy‐poly(oxy‐1,2‐ethanediyl) (Carbowax 350) as a phase transfer catalyst. This study describes the influence of reaction variables on rate and the partitioning of dichlorocarbene between dichlorocyclopropanation and hydrolysis. The results are consistent with a kinetic model derived for the case where mass transfer is not rate limiting. However, this does not apply at high conversions where mass transfer control occurs due to large increases in viscosity. Higher BR concentrations can be achieved by replacing chloroform with methylene chloride containing stoichiometric amounts of chloroform. This mass action effect causes more favorable partitioning toward cyclopropanation; otherwise, chloroform and methylene chloride behave similarly as solvents. Water is an essential component in this reaction because it greatly increases the ability of the catalyst to extract sodium hydroxide into the organic phase.
Organogermane homopolymers and copolymers with organosilane
Authors: Trefonas P. , West R.
Published: April 2003

The first high molecular weight soluble, formable organogermane homopolymer (n‐Bu2Ge)n was synthesized by the sodium coupling of n‐Bu2GeCl2 in toluene. Soluble organogermane/organosilane copolymers [(X2Ge)x(YZSi)y]n were prepared by sodium coupling of X2GeCl2 and YZSiCl2 in different molar ratios (X = n‐bu, Ph; Y = n‐hexyl, cyclohexyl; Z = Me). Germanium‐containing polymers and copolymers with organosilanes are highly absorbing between 300–360 nm, with the absorption maxima dependent on the nature of the substituent and the ratio of X2Ge:YZSi in the polymer. These polymers are photoactive and display bleaching behavior with photoscission.
Ethylene propylene diene terpolymers produced with a homogeneous and highly active zirconium catalyst
Authors: Kaminsky Walter , Miri Massoud
Published: April 2003

EPDM terpolymers with ethylidene norbornene as diene monomer could be prepared by means of a soluble Ziegler catalyst formed from biscyclopentadienyl zirconium dimethyl and methylaluminoxane. The overall activities lie between 100 and 1000 kg EPDM/(molZr h bar), obtainable at zirconium concentrations as low as 5 × 10−7 mol/L. After an induction period (0.5–5 h) the polymerization rates increased and then leveled to a value which was constant for several days. From copolymerization kinetics reactivity ratios r12 = 31.5, r21 = 5 × 10−3, and r13 = 3.1 could be derived, and by 13C‐NMR spectroscopy r12 · r21 = 0.3 was found (1: ethylene, 2: propylene and 3: ethylidene norbornene). The regiospecifity of the catalyst toward propylene leads exclusively to the formation of head‐to‐tail enchainments. The diene polymerizes via vinyl polymerization of the cyclic double bond, and the tendency to branching is low. Molecular weights were estimated between 40,000 and 160,000. The average molecular weight distribution of 1.7 is remarkably narrow. Glass transition temperatures of −60 to −50°C could be observed. The cure behavior and the physical properties of cured samples were also tested.
Polymerization of para‐xylylene derivatives (parylene polymerization). II. Heat effects during deposition of parylene C at different temperatures
Authors: Gazicki M. , Surendran G. , James W. , Yasuda H.
Published: April 2003

Thermal effects accompanying vacuum deposition of poly(chloro‐para‐xylylene) in the temperature range between −196 and 0°C have been studied using two separate methods. One is based on the recording of the rate of evaporation of liquid nitrogen and it is used for the deposition at −196°C, and the second involves the recording of changes in the substrate temperature and is used for the deposition in the range of −162 to 0°C. These methods enable us to observe two distinct effects: fast (discrete), resulting in the appearance of sharp, exothermic spikes; and slow (continuous), resulting in the shift of the baseline. The shift of the baseline exhibits a well‐defined maximum at about −65°C and this temperature is attributed to the melting point of the monomer. The fast process always occurs below this temperature and is explained as a solid state, chain addition polymerization. The quantification of the heat effect at −196°C strongly suggests that the quinonoid form of the monomer participates in the propagation step of this chain reaction. The fast (solid state) and the continuous modes of polymerization may occur simultaneously in the range of about −140 and −65°C. The frequency of the initiation which is the formation of dimer radical seems to control the occurrence of these two modes of polymerization.
Hydrogen peroxide determination by I.R. specular reflectance spectroscopy during uncatalyzed and copper (oxides)‐catalyzed oxidation of isotactic polypropylene
Authors: Jellinek H. H. G. , Kachi H. , Chodak I. , Czanderna A. W.
Published: April 2003

IR specular reflectance spectra with respect to hydrogen peroxide formation during uncatalyzed and Cu (oxide)‐catalyzed oxidation of isotactic Polypropylene films have been measured as function of time and temperature (90–130°C). Energies of activation for the various cases have been obtained. The originally proposed kinetic scheme based on oxygen‐absorption measurements has been modified in order to accommodate the spectroscopical results. The amount of ROOH groups present at any time on the polymer is very small, indicating relatively slow rates of ROOH formation and fast rates of their decomposition. The kinetic scheme fits well the experimental data. However, the reasons for the variations of the relevant energies of activation obtained for the catalyzed oxidation in absence and presence of the main volatile reaction products, H2O and CO2, are not yet understood, i.e., the mechanism needs further investigations.
Cure of epoxy resins with esters of cyanoacetic acid
Authors: Renner Alfred , Moser Roland , Bellus Miriam , Fuhrer Hermann , Spitzer Michaela
Published: April 2003

Esters of cyanoacetic acid are a novel class of epoxy curing agents. The model reaction between ethyl cyanoacetate (ECA) and phenyl glycidylether (PGE) yielded a cyano‐spiro‐dilactone under conditions similar to the resin cure. The structure of the spiro compound resulting from 2 ECA and 2 PGE was elucidated by MS, IR, 1H‐, and 13C‐NMR techniques. Ammonia is split off from 1 ECA and acts in statu nascendi as a satellite hardener. An overall model reaction equation for the cyanoacetyl cure is proposed. The cure of bisphenol A–diglycidylether (BADGE) with ECA and with neopentylglycol‐biscyanoacetate (NPGCA) is described over a wide range of the molar ratio. Clear and tough solids are obtained with a glass transition temperature up to 130°C. Cyanoacetates are latent hardeners requiring a curing initiator. Since N‐4‐chlorophenyl N′‐dimethylurea is a latent initiator, liquid “one‐shot” systems can be formulated that are stable at room temperature and harden quickly above 120°C. Heat aging properties of cured specimens are reported. A series of novel liquid, resinous, and crystalline cyanoacetates and their potential as curing agents are described.
Some studies on plasma‐initiated polymerization of (MMA) and on plasma polymerized (PMMA)
Authors: Demi̇rel G¨︁nay , Akovali Güneri
Published: April 2003

Methyl methacrylate was polymerized in the liquid state by plasma initiation. The conversion curves obtained for different polymerization conditions strikingly illustrated the effects of applied vacuum, discharge period, post‐polymerization, time, and temperature on monomer conversion and polymerization rate. The plasma initiated PMMA samples are not as monodisperse, as previously predicted.
Nucleic acid base grafted polyethylenimine. Cytosyl pendant groups: Elucidation of structure with solution spectroscopy
Authors: Chu V. P. , Overberger C. G.
Published: April 2003

In a previous paper, potassium 2‐(cytos‐1‐yl)propanoate was grafted onto polyethylenimine of various molecular weights. These water‐soluble polynucleotide analogs exhibited remarkable properties in their solution ultraviolet spectra. High hypochromicity values of 50% and 54% have been observed in alkaline aqueous solution and 50% trifluoroethanol solution, respectively. Percent hypochromicity value was observed to be directly proportional to percent graft. Red shift and hyperchromicity as a function of pH were observed for both the monomer model and the graft polymers. Light‐scattering experiments on nucleic acid base grafted hydrophilic polymer backbones were carried out. Radius of gyration and second virial coefficient values indicated stiff macromolecules, rodlike in nature. Therapeutic potential of cytosyl grafted polyethylenimine was suggested by the results from continuous mixing experiments with polyinosinic acid and polyguanylic acid. Job plots showed enhanced hypochromicity, whose magnitude was dependent upon the polynucleotide and the base‐base distance.
Plasma‐polymerized organosiloxane membranes prepared by simultaneous doping of I2 molecules and the effect on liquid permeability
Authors: Osada Yoshihito , Takase Mitsuo
Published: April 2003

Glow‐discharge plasma polymerization of hexamethylcyclotrisiloxane was carried out on the cellulose acetate substrate in the presence of iodine crystal and the effect of I2 doping on liquid permeability such as water, cyclohexane, alcohol homologues, and a water–alcohol mixture was investigated. It was found that I2‐doped poly(siloxane) (PHMS–I2) membrane exhibited larger water permeability than nondoped (PHMS) membrane with anomalous pressure dependence (fourth power with pressure gradient). The permeability of alcohol homologues of PHMS membrane increased with increasing the molecular size and the hydrophobicity, whereas that of PHMS–I2 membrane decreased significantly. The presence of a small amount of hemoglobin also increased the water permeability of both membranes. From the results of flow tests of various kinds of fluid it was assumed that these membranes permeate the liquid predominantly by solution‐diffusion mechanism.
Synthesis and characterization of polymers derived from 2,5‐dimethoxy‐terephthaldehyde and 2,5‐dimethoxy‐terephthalic acid
Authors: Diaz F. R. , Tagle L. H. , Godoy A. , Hodgson C. , Olivares J. P.
Published: April 2003

Polyamides were synthesized from 2,5‐dimethoxyterephthaloyl dichloride and diamines. Also, polyimines and polyaldoles were prepared from 2,5‐dimethoxy‐terephthaldehyde with diamines and ketones. The polymers were characterized by elemental analysis and infrared and NMR spectroscopy. Their intrinsic viscosity, glass transition temperature, and thermaldecomposition temperatures were determined.
Polyesters from 2,6‐dihydroxy‐9,10‐dihydro‐9,10‐ethanoanthracene and 2,6‐dihydroxyanthracene
Authors: Frazer A. H. , Anderson B. C. , Fukunaga T.
Published: April 2003

High molecular weight, film‐forming, amorphous polyesters have been prepared from 2,6‐dilydroxy‐9,10‐dihydro‐9,10‐ethanoanthracene with adipic, sebacic, dodecanoic, isophthalic, 4,4′‐oxybibenzoic, 2,6‐naphthoic, 4,4′‐bibenzoic, and terephthalic acid. Thermal elimination of ethylene from these polymers has yielded the corresponding polyesters from 2,6‐dihydroxyanthracene which were of high molecular weight, film forming, and crystalline.
The polymerization of furfuryl acetate in acetonitrile
Authors: Buchwalter Stephen L.
Published: April 2003

The complex resins derived from furfuryl‐alcohol polymerization are a result of at least four competing reactions. By converting the alcohol to its acetate ester, however, three of these reactions can be eliminated. The simpler polymer derived from furfuryl acetate has been characterized spectroscopically, and an interesting chromophoric side reaction of the polymerization has been identified. The remarkable ability of the polymer to crosslink at room temperature upon precipitation from solution is also of interest.
Carbazole‐substituted dehydroalanine main chain polymers. Synthesis and characterization of poly[methyl 2‐(9‐carbazolyl) acetylaminopropenoate] and poly[2‐(9‐carbazolyl) acetylaminopropenoic acid]
Authors: Arora Kartar S. , Overberger C. G.
Published: April 2003

The preparation and radical‐initiated polymerization of a carbazole‐substituted N‐acylated dehydroalanine, namely, 2‐(9‐carbazolyl)acetylaminopropenoic acid (7) and its methyl ester (6) is reported. The monomers 6 and 7 were prepared by dehydrochlorination of N‐acylated β‐chloroalanine derivatives. The monomer model compounds for the two polymers, namely, 2‐(9‐carbazolyl)acetylamino‐2‐methylpropanoic acid (11) and its methyl ester (10), were also prepared. The polymers and their monomer model compounds were characterized by elemental analysis, IR and 1H‐NMR spectra. The polymers 12 and 13 of different molecular weights could be obtained by changing the monomer‐to‐initiator ratios used in polymerization experiments.
Synthesis and flammability of copoly(isophthalamide)s. II. With pendant phosphorus groups
Authors: Gravalos K. G.
Published: April 2003

A series of copoly(isophthalamide)s containing pendant phosphorus, dialkoxyphosphinylphenylene, diphenylphosphinylphenylene, and diphenylphosphinylamino groups were prepared. The introduction of phosphorus groups was performed to a degree of ca. 5–17 mol %. From the limiting oxygen index (LOI) measurements, it was found that the LOI of P‐substituted polyamides increased by ca. 14–40%. From TG and DTG analysis the maximum rate and the percentage of mass loss of the decomposition stages were evaluated. From these measurements the mode of action of phosphorus groups in the solid or gas phase was assessed. In the solid phase, due to crosslinking reactions, a reduction of the maximum rate and the percentage of mass loss in the decomposition stage of main chain amide bonds was observed. In this case the increase of the char yield at 700°C of the P‐substituted polyamides was in the range of 21–36%. © 1993 John Wiley & Sons, Inc.
Radicals in the synthesis of sulphur dioxide‐based copolymers
Authors: Hwang Jimmy S. , Tsonis Christos P.
Published: April 2003

Free radicals generated from a number of olefinic, acetylenic, and vinyl monomers in the presence of sulphur dioxide and tert‐butyl hydroperoxide were investigated. In all reaction systems a sulphonyl propagating radical first appears which depropagates into the corresponding carbon radical at higher temperatures. The sulphonyl radicals were observed between −119 and −44°C, whereas the carbon radicals were observed from −63 to −1°C. The order of decreasing reactivity of the reaction system was: 3‐hexyne > 1‐heptene > methyl acrylate > acrylonitrile > 1‐heptyne. © 1993 John Wiley & Sons, Inc.
Studies on thermotropic liquid crystalline polymer. XI. Effect of amide group on thermotropic liquid crystalline polymer properties
Authors: Chang Teh‐Chou , Li Chien‐Hui
Published: April 2003

A series of poly(azomethine)s containing amide, ether, or ester groups was prepared by the condensation of dialdehydes with various diamines. The thermotropic liquid crystalline properties were examined by DSC and microscopic observations. The effects of the number and position of amide groups, which are attached to the rigid segment, on the thermotropic liquid crystalline properties of the homo‐and copoly(amide‐azomethine‐ether)s were also investigated in this study. The copolymerization took place by changing the amount of amide group to obtain copoly(amide‐azomethine) (P13 and P14) which exhibit thermotropic liquid crystalline properties. The poly(azomethine)s containing ether or ester groups also exhibited thermotropic liquid crystalline properties. © 1993 John Wiley & Sons, Inc.
Polyesters, polycarbonate, and polyurethanes from a novel monomer: α,α,α′,α′‐tetramethyl‐1,4‐tetrafluorobenzenedimethanol
Authors: Guo X. Andrew , Hunter Allen D.
Published: April 2003

The novel diol monomer, α,α,α′,α′‐tetramethyl‐1,4‐tetrafluorobenzenedimethanol, has been synthesized by a convenient route which involves the addition of acetone to 1,4‐dilithiotetrafluorobenzene and can be purified by washing with hexanes. It does not directly undergo condensation polymerizations with diacid chlorides. Its disodium salt, prepared by its reaction with sodium hydride, similarly fails to undergo such polymerizations readily. However, the dilithium salt, prepared in situ by the reaction of the title diol with 2 equiv of n‐butyllithium in tetrahydrofuran, is suitable for the preparation of various classes of condensation polymers. Four polyesters and one polycarbonate derived from the reactions of the dilithium salt of the diol with adipoly dichloride, sebacoyl dichloride, isophthaloyl dichloride, terephthaloyl dichloride, and phosgene and two polyurethanes derived from its reactions with tolylene‐2,4‐diisocyanate and methylene‐di‐1,4‐phenyl diisocyanate were prepared. Each was fully characterized by GPC, NMR, IR, and UV‐visible spectroscopies, and the results of these studies are reported herein. © 1993 John Wiley & Sons, Inc.
Preparation of high molecular weight polyhydrazides from hydrazine monohydrochloride using phenylphosphonic dichloride and phosphorus compounds as additives
Authors: Higashi Fukuji , Lee Yen‐Nen
Published: April 2003

Significantly high molecular weight poly(isophthalic dihydrazide) of inherent viscosity up to 1.6 (DMSO) was prepared by the reaction of isophthalic acid and hydrazine monohydrochloride using phenylphosphonic dichloride in the presence of phosphorus compounds such as phosphine oxides. The phosphorus compounds used as additives were assumed to be involved in the reaction through a complexation with the monohydrochloride, enhancing the reactivity of the hydrazine. It was attempted to prepare copoly(hydrazide‐amides) with different monomer sequences by changing the relative reactivity between diamines and the hydrazine using the phosphorus compounds. The copoly(hydrazide‐amide)s were studied in terms of the dehydration reaction of hydrazide groups into 1,3,4‐oxadiazole groups. © 1993 John Wiley & Sons, Inc.
Polymeric complexed membranes used as oxygen carrier: Axial and in‐plane ligand effects
Authors: Hsiue Ging‐Ho , Yang Jen‐Ming
Published: April 2003

The complex formation reaction of modified styrene–butadiene–styrene block copolymer (SBS‐g‐VP and ESBS) with cobalt Schiff base (CoS) in chloroform solution is studied. The coordination number and formation constant are determined by the Miller method. The polymeric complexed membranes (SBS‐g‐VP–CoS and ESBS–CoS and ESBS–CoS) are made by solution casting method. The kinetics of oxygen binding to polymeric complexed membranes (SBS‐g‐VP–CoS and ESBS–CoS) is studied and the equilibrium, association, and dissociation constants are determined. The effects of polymeric axial ligand and of the equatorial chelate group are discussed. © 1993 John Wiley & Sons, Inc.
Propenyl ethers. I. The synthesis of propenyl ether monomers
Authors: Crivello J. V. , Jo K. D.
Published: April 2003

A variety of mono‐, di‐, and multifunctional propenyl ethers were readily prepared in high yields by the condensation of alcohols with allyl halides followed by the base or transition metal‐catalyzed rearrangement of the corresponding allyl ethers. Their straightforward synthesis and high reactivity in cationic UV curing make these monomers highly attractive for a variety of applications. The successful photopolymerization of these monomers has required the synthesis of specially tailored onium salt photoinitiators. © 1993 John Wiley & Sons, Inc.
Synthesis and radical polymerization of vinyl monomers having oxazolidone moiety
Authors: Atobe Ichiro , Takata Toshikazu , Endo Takeshi
Published: April 2003

Oxazolidone group‐containing vinyl monomers, 4‐(2‐oxo‐3‐oxazolidinyl)methylstyrene (OS) and 4‐[2‐(2‐oxo‐3‐oxazolidinyl)ethoxy]methylstyrene (OES), were synthesized and their polymerization and copolymerization behaviors with styrene (St), p‐methoxystyrene (PMS), and m‐hydroxystyrene (MHS) were investigated. OS was prepared in 70% yield by the reaction of 2‐oxazolidone with p‐chloromethylstyrene in the presence of sodium hydride. OES was obtained by the similar reaction of p‐chloromethylstyrene with N‐hydroxyethyl‐2‐oxazolidone which was prepared by the reaction of 2‐oxazolidone with ethylenecarbonate. Homopolymerization of OS and OES afforded mainly gelled polymers, but also soluble polymers on high dilution. In the copolymerization with styrene derivatives, an alternating nature was suggested from the copolymerization parameters obtained by either the nonlinear least‐squares analysis method or the Fineman–Ross method. The alternating copolymerizability decreased in the following order: MHS > PMS > St. Q−e values of OS and OES were calculated and demonstrated that OS and OES behaved as stronger electron‐accepting monomers in the copolymerization with MHS than in those with St and PMS. The copolymerization behavior of OS (OES) with MHS was compared with those of 4‐(2‐oxo‐1‐pyrrolidinyl)methylstyrene (PS) and 4‐[2‐(2‐oxo‐1‐pyrrolidinyl)ethoxy]methylstyrene (PES). From an IR study examining the shift of carbonyl absorption by addition of MHS, the interaction which contributed to the increase of the alternating copolymerizability in the copolymerization of OS (OES) with MHS was concluded to be based on hydrogen bonding. © 1993 John Wiley & Sons, Inc.
Molecular design of three‐dimensional artificial extracellular matrix: Photosensitive polymers containing cell adhesive peptide
Authors: Moghaddam Minoo Jalili , Matsuda Takehisa
Published: April 2003

A photodimerizable monomer, methacrylic acid‐(7‐coumaroxy) ethyl ester, was synthesized and was copolymerized with a hydrophilic monomer (N,N‐dimethylacrylamide) to obtain a water‐soluble photosensitive polymer. Irradiation of the copolymer film and aqueous solution with a high‐pressure mercury lamp resulted in highly hydrated gel. The gel yield was enhanced with the content of the photodimerizable group in the copolymer and the irradiation time. The degree of swelling of the gels decreased concomitantly. Incorporation of the well‐known cell adhesive peptidyl ligand Arg‐Gly‐Asp‐Ser(RGDS) into photosensitive copolymers attained a biologically active hydrophilic gel matrix upon UV light irradiation. Irradiation of a buffer solution of the latter copolymer premixed with smooth muscle cells entrapped the cells throughout the gel matrix. This indicates that the designed polymer and the resulting cell‐incorporated hydrogel are biomimic to an extracellular matrix and to the media of the vascular wall, respectively. © 1993 John Wiley & Sons, Inc.
Synthesis of α,ω‐arylamine functionalized poly(dimethylsiloxane)s
Authors: Babu J. Ramesh , Sinai‐Zingde G. , Riffle J. S.
Published: April 2003

This research has focused on the development of telechelic, aromatic amine functional, poly(dimethylsiloxane) oligomers without any aliphatic components in the polymer backbone. The intent is to produce flexible oligomers with enhanced thermal stability for incorporation into materials which will be processed at elevated temperatures. The poly(dimethylsiloxane)s have been synthesized using living polymerization of hexamethylcyclotrisiloxane with protected aniline derivatives as initiators and termination reagents for the reactions. Low molecular weight oligomers prepared using the living polymerization method can be easily converted to a range of higher, controlled molecular weight materials in redistribution reactions. A basic tetramethylammonium siloxanolate catalyst in conjunction with octamethylcyclotetrasiloxane has been used for the equilibration procedure. © 1993 John Wiley & Sons, Inc.
Syntheses, structural characterizations, and thermal resistances of new epoxy–imide polymers
Authors: Shau Min‐Da , Chin Wei‐Kuo
Published: April 2003

A new type of imide–epoxy resin in which imide compounds were grafted on the main chain of the epoxy was synthesized. The imide compounds used were mono (aminophthalimide)s. The structures of imide monomers and imide–epoxy polymers were confirmed by spectra characterizations of IR, 1H‐, and 13C‐NMR. The thermal resistances and solubilities of synthesized imide–epoxy were also studied. © 1993 John Wiley & Sons, Inc.
Dual‐phase solid polymer electrolytes prepared from styrene–butadiene copolymer latices
Authors: Ichino Toshihiro , Matsumoto Morihiko , Rutt J. Steven , Nishi Shiro
Published: April 2003

A new dual‐phase solid polymer electrolyte system has been proposed. In this system, a network of ion pathways is formed in a low‐polarity, host polymer matrix. A series of electrolytes were prepared from styrene‐butadiene copolymer latices with dissolved lithium salts. Polymer films were formed from these latices, and then impregnated with γ‐butyrolactone (γ‐BL) or γ‐butyrolactone/dimethoxyethane mixture (γ‐BL/DME), giving latex polymer electrolytes. The ionic conductivity of the polymer electrolyte system increased with increasing solvent content, although a distinct percolation threshold was not measured. Ionic conductivity also increased with the use of DME cosolvent, with the highest conductivity being 1.4 × 10−4S/cm. Complex impedance diagrams are discussed. The diagrams show significant deviations from the ideal. TEM/SEM observations are consistent with the desired dual‐phase morphology. © 1993 John Wiley & Sons, Inc.
Addition of chlorofluorocarbene to poly(1‐methyl‐1‐phenyl‐1‐sila‐cis‐pent‐3‐ene) and poly(1,1‐dimethyl‐1‐sila‐cis‐pent‐3‐ene): Characterization of chlorofluorocyclopropanated polymer microstructures by 1H‐, 13C‐, 19F‐, and 29Si‐NMR spectroscopy
Authors: Wang Liming , Liao Charles X. , Weber William P.
Published: April 2003

Chlorofluorocarbene, generated by the sodium iodide catalyzed decomposition of phenyl(dichlorofluoromethyl)mercury, adds to the carbon‐carbon double bonds of poly(1‐methyl‐1‐phenyl‐1‐sila‐cis‐pent‐3‐ene) (I) and poly(1,1‐dimethyl‐1‐sila‐cis‐pent‐3‐ene) (II) to yield poly(3,4‐chlorofluoromethylene‐1‐methyl‐1‐phenyl‐1‐sila‐cis‐pent‐3‐ene) (CIFC‐I) and poly(3,4‐chlorofluoromethylene‐1,1‐dimethyl‐1‐sila‐cis‐pent‐3‐ene) (CIFC‐II). Similarly, two series of random partially chlorofluorocyclopropanated polymers have been prepared. The microstructures of these adduct polymers have been determined by 1H‐, 13C‐, 19F‐, and 29Si‐NMR spectroscopy. The glass transition temperatures (Tg's) depend on the extent of chlorofluoropropanation of these polymers. These copolymers become less thermally stable as the extent of chlorofluorocyclopropanation increases. © 1993 John Wiley & Sons, Inc.
Thermogravimetric study of polyacrylamide with evolved gas analysis
Authors: Van Dyke John D. , Kasperski Kim L.
Published: April 2003

Dried samples of polyacrylamide in an He atmosphere have been subjected to thermogravimetric analysis in the 30–600°C range, and the evolved gases were monitored by FTIR. Water, ammonia, and small quantities of carbon dioxide are released in the first stages of decomposition (220–340°C), where the polymer chains remain intact and the reaction occurs on the pendant amide groups. In the second stage of decomposition (340–440°C), the majority of the weight loss occurs, and main chain breakdown occurs, releasing carbon dioxide, water, nitrile compounds, and imides. Trapping of the gases in this stage and analysis by GC–FTIR and GC–MS reveals the presence of more than 20 decomposition products, and confirms that a large proportion of these can be assigned to glutarimide and its substituted analogs. Imidization and dehydration reactions on the amide groups, as well as free radical breakdown of the main chains, with inter‐ and intramolecular hydrogen transfer, can account for many of the products of the decomposition. © 1993 John Wiley & Sons, Inc.
New epoxy‐terminated oligoesters: Precursors to totally biodegradable networks
Authors: Storey Robson F. , Hickey Timothy P.
Published: April 2003

Two types of novel biodegradable epoxy resins, carrying cycloaliphatic‐epoxy and glycidyl ester end‐groups, have been synthesized from hydroxy‐telechelic oligoesters. The cycloaliphatic‐epoxy end‐groups were based on either methyl cis‐4‐cyclohexene‐2‐(carboxylic acid)‐1‐carboxylate or 3‐cyclohexene‐1‐carboxylic acid. These compounds were reacted with hydroxy‐telechelic poly(ε‐caprolactone‐co‐D,L‐lactide) oligoesters, yielding cycloaliphatic‐olefin‐terminated oligomers. Conversion of the olefin to the epoxide groups was achieved using a phase transfer epoxidation with an inorganic peracid derived from the reaction of phosphoric acid, sodium tungstate, and hydrogen peroxide. Aliquat 336, a quaternary ammonium salt, acted as the phase transfer catalyst. Nearly theoretical conversion of hydroxy to epoxy end‐groups was achieved in only one case, however, alternative variations of this method of synthesis show promise. To prepare glycidyl ester‐terminated prepolymers, hydroxy‐telechelic poly(ε‐caprolactone) oligoesters were reacted with succinic anhydride, in 1,2‐dichloroethane with 1‐methylimidazole as catalyst, resulting in (carboxylic acid)‐terminated oligomers. After conversion of the end‐groups to the potassium carboxylate salt by titration with methanolic KOH, the isolated salt was dried and reacted with epibromohydrin in acetonitrile at reflux, using an 18‐C‐6 crown ether as the phase transfer catalyst, thus preparing the (glycidyl ester)‐telechelic prepolymer. Epoxide equivalent weights differed by 2.7–7.1% from the theoretical values. These cycloaliphatic‐epoxide and glycidyl ester‐terminated prepolymers may be crosslinked with anhydrides or amines, respectively, to produce totally bioabsorbable networks. © 1993 John Wiley & Sons, Inc.
Ultrastructure studies of polystyrene‐based side‐chain liquid‐crystalline copolymers containing charge transfer groups
Authors: Schleeh T. , Imrie C. T. , Rice D. M. , Karasz F. E. , Attard G. S.
Published: April 2003

A series of new side‐chain liquid‐crystalline copolymers has been prepared, and the thermal properties of the individual copolymers have been determined. These copolymers are derived from atactic polystyrene and contain both 4‐methoxyazobenzene and 4‐nitroazobenzene mesogens; these are linked through octyl spacers to the polystyrene backbone. All the copolymers exhibit a smectic phase that has been assigned smectic A on the basis of polarizing microscopy and x‐ray diffraction studies. The glass transition temperatures of the polymers exhibit a linear dependence on composition, whereas the clearing temperatures and the associated entropies show significant deviations from such behavior. The smecticisotropic transition temperatures of the copolymers are higher than those of the composition‐weighted averages for the corresponding homopolymers, whereas the entropies of transition are lower than expected. X‐ray diffraction studies of fiber samples revealed that the director of the mesophase is oriented perpendicular to the fiber axis. The liquid‐crystalline polystyrene containing 25 mol % nitro‐substituted mesogen shows an unusual SA‐phase WAXS pattern. The copolymers were investigated further by 13C CP/MAS NMR spectroscopy, and the observed changes in the spectra are analyzed in terms of chemical composition and local electronic environment. The application of the interrupted decoupling technique revealed that the spacer contains a number of gauche defects. These observations lead us to suggest possible microstructural arrangements in the smectic phase. © 1993 John Wiley & Sons, Inc.
Synthesis and characterization of polymethylphenylsilane–polystyrene block copolymers
Authors: Demoustier‐Champagne S. , De Mahieu A.‐F. , Devaux J. , Fayt R. , Teyssie Ph.
Published: April 2003

Block copolymers of polymethylphenylsilane (PMPS) and polystyrene (PS) have been successfully prepared by the condensation of α,ω‐dichloro‐polymethylphenylsilane with polystyryl‐lithium. These new materials have been characterized by UV spectroscopy, 29Si‐NMR, and size exclusion chromatography. These block copolymers show a good emulsifying activity to compatibilize blends of the two homopolymers (PMPS and PS). © 1993 John Wiley & Sons, Inc.
Synthesis and properties of fluorinated telechelic macromolecular diols prepared by radical grafting of fluorinated thiols onto hydroxyl‐terminated polybutadienes
Authors: Ameduri Bruno , Boutevin Bernard , Nouiri Mustapha
Published: April 2003

The radical grafting of CnF2n +1 CH2CH2SH (n = 6,8) onto the double bonds of hydroxyl‐terminated liquid polybutadienes (HTPBD) was studied. Various methods for investigating the amount of grafting (titration of residual thiol and fluorine analysis) were used and compared. The nature and the amount of the initiator, the quantity of thiol, the temperature and the time of the reaction. the solvent, and the microstructure of HTPBD were optimized. The kinetic aspect showed that the thiol disappeared according to a first‐norder law. A method using up to 100% of grafting fluorinated mercaptan was described and standards were set up with fluorine contents of 5–59% to evaluate the physicochemical properties of these thioether group‐containing polymers: solubility, refractive index, intrinsic and dynamic viscosities, and thermal characteristics (glass transition and decomposition temperatures). Finally, the surface properties of these standards showed improvements of surface energy as low as 9 mN m−1 for a totally saturated fluorinated HTPBD. © 1993 John Wiley & Sons, Inc.
New three‐component initiation systems in UV curing: A time‐resolved laser‐spectroscopy investigation
Authors: Fouassier Jean‐Pierre , Ruhlmann Denis , Takimoto Yasuyuki , Harada Masahiko , Kawabata Masami
Published: April 2003

An investigation of the excited state processes in a three‐component initiating system based on a new ketone/amine/onium salt combination has been carried out for the first time. The results obtained through time‐resolved laser spectroscopy and the data gained in radical photopolymerization experiments suggest that the addition of an onium salt to the usual ketone/amine system mostly result in a decrease of the termination reaction of the growing macromolecular chains, thus allowing an increase of the rate of polymerization. © 1993 John Wiley & Sons, Inc.
Synthesis and characterization of poly(itaconate ester)s with etheric side chains
Authors: Coltrain Bradley K. , Ferrar Wayne T. , Salva John M.
Published: April 2003

The synthesis and characterization of poly(itaconate ester)s with short poly(ethylene oxide) side chains have been studied. It was found that the monomer syntheses via esterification of itaconic acid resulted in incomplete esterification leaving up to 35 mol % monomers with carboxylic acid functionality. These acid groups were then incorporated into the polymers. This acid incorporation has not previously been reported, nor have the properties of the copolymers been studied. Techniques were developed to effectively remove the acid impurities to generate pure homopolymers. Titration and gas chromatographic techniques were developed to study the amount of acid impurity in the monomers, and titration was also used to characterize the polymers. Size exclusion chromatography and differential scanning calorimetry were used to study both the homopolymers and copolymers. It was found that the location and breadth of the glass transition is a function of acid content. Finally, isomerization of the itaconate monomers to the inactive mesaconate was also found to be a problem during the synthesis. Pure mesaconate and citraconate monomers were synthesized and characterized by 1H‐NMR. © 1993 John Wiley & Sons, Inc.
The synthesis and characterization of amine‐terminated poly(aryl ether ketone)s as a function of side group and molecular weight
Authors: Bennett Greggory S. , Farris Richard J.
Published: April 2003

It is shown that amine‐terminated poly(aryl ether ketone)s based on the reaction of 4,4'‐difluorobenzophenone, and a substituted hydroquinone [either methylhydroquinone (MePK), t‐butylhydroquinone (tBPK), or phenylhydroquinone (PhPK)] of controlled molecular weight and high amine‐termination efficiency can be synthesized by a two‐step reaction technique. Attempts to synthesize analogous materials by a one‐step method were shown to be unsuccessful. The side groups are shown to have a large influence on the aromatic proton chemical shifts and this effect is characterized. The side groups and molecular weight are also shown to influence the thermal transitions of the respective polymers. The tBPK polymer possessed the highest glass transition temperature, while the MePK polymer was found to be the only semi‐crystalline polymer; a unit cell is proposed. The side groups and molecular weight effects are also characterized as a function of thermal stability and mechanical properties. © 1994 John Wiley & Sons, Inc.
Thermotropic copolyamides from triethyleneglycol bis(4‐carboxyphenyl)ether and two kinds of aromatic diamines
Authors: Higashi Fukuji , Zhang Wen Xion , Nakajima Kohji
Published: April 2003

Thermotropic copolyamides were prepared from triethyleneglycol bis(4‐carboxy‐phenyl)ether (PEG3) and two types of diamines, substituted p‐phenylenediamines and 4,4'‐diaminodiphenyls, and depression of melting point and isotropization temperature of the copolymers produced were measured as a function of diamine combination. The depression was not practically observed by the combinations of homologous diamines with several kinds and numbers of substituents, but significant by those of the diamines with different lengths of the mesogenic segments, and by the molar ratios of the diamines employed. The effect was discussed in terms of deviation of interchain hydrogen bonding between amide bonds in the main chain. © 1994 John Wiley & Sons, Inc.
Plasma deposition of thin films from a fluorine‐containing cyclosiloxane
Authors: Favia Pietro , Caporiccio Gerardo , D'Agostino Riccardo
Published: April 2003

Thin films have been deposited from radio‐frequency glow discharges fed with vapors of a silicon‐ and fluorine‐containing organic compound, namely 2,4,6‐tris[(3,3,3‐trifluoropropyl) (methyl)] cyclotrisiloxane, in mixture with argon.
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2,4,6‐tris[(3,3,3‐trifluoropropyl)(methyl)]cyclotrisiloxane

A triode reactor has been utilized to deposit films by independently changing substrate temperature and bias‐induced ion‐bombardment. Laser interferometry, electron spectroscopy for chemical analysis and Fourier‐transform infrared spectroscopy have been used to monitor film growth rate and composition. Results unambiguously show an activating effect of the ion‐bombardment, which confirm the validity of the ion‐assisted deposition model utilized for the plasma deposition of both teflon‐ and silicone‐like films. In our experiments, low substrate temperature and bias conditions results in films with a “monomer‐like” stoichiometry, while drastic conditions give origin to materials with a completely different composition and a markedly increased hardness. © 1994 John Wiley & Sons, Inc.
Synthesis and properties of polyoxyarylenesiloxanes
Authors: Nye Susan Adams , Swint Sandra A.
Published: April 2003

High molecular weight polymers containing oligosiloxanes in the backbone were made by the reaction of aromatic diols with α,ω‐diaminosiloxane homologs. The glass transition temperatures dropped by 30–40°C in a homologous series with each siloxane added. The thermal stability also suffered when increasing the number of siloxane groups. The polymers all displayed high % char measurements and one polymer (disiloxane) tested had a V0 rating by UL‐94 testing. The trisiloxane‐containing polymer had a high percent elongation at break (>300%). All the polymers tested were fairly susceptible to hydrolysis. © 1994 John Wiley & Sons, Inc.
Polymerization kinetics and volume relaxation behavior of photopolymerized multifunctional monomers producing highly crosslinked networks
Authors: Anseth Kristi S. , Bowman Christopher N. , Peppas Nikolaos A.
Published: April 2003

Multifunctional monomers (trimethylol propane trimethacrylate, trimethylol propane triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol monohydroxy pentaacrylate) were photopolymerized with 2,2‐dimethoxy‐2‐phenylacetophenone as the photoinitiator to produce highly crosslinked networks. The volume shrinkage behavior and the reaction kinetics were studied under various reaction conditions. The volume shrinkage and maximum functional group conversion were dependent on the number of functional groups, type of functional group, and the curing conditions. The maximum functional group conversion was also dependent on the reaction temperature. All the polymerized systems exhibited a strong coupling between the volume relaxation and the reaction kinetics. The kinetic constants were also determined as a function of conversion, and the termination mechanism was found to be reaction diffusion dominated even at low conversions. The importance of these results on the prediction of the reaction behavior for multifunctional monomers producing highly crosslinked polymers is discussed. © 1994 John Wiley & Sons, Inc.
Whiskers. VII. Homo‐ and copolyesters of 6‐hydroxythioxanthone‐2‐carboxylic acid
Authors: Kricheldorf Hans R. , Adebahr Thorsten
Published: April 2003

6‐Hydroxythioxanthone‐2‐carboxylic acid (HTCA) was prepared from commercial dimethylnitroterephthalate via 2‐(4'‐hydroxythiophenyl) terephthalic acid. HTCA was acetylated and polycondensed in an inert reaction medium at 350 or 400°C. An insoluble and infusible, highly crystalline polyester was obtained, which did not form whisker‐like crystals. Furthermore, copolyesters with 4‐hydroxybenzoic acid (4‐HBA) were synthesized and whiskers were obtained at a molar ratio of 1 : 9 (in favor of 4‐HBA). A meltable, nematic copolyester was prepared by cocondensation of silylated 6‐acetoxythioxanthone‐2‐carboxylic acid and silylated 4‐acetoxybenzoic acid in bulk. © 1994 John Wiley & Sons, Inc.
NMR study of PMR‐15 prepolymerization steps
Authors: Milhourat‐Hammadi A. , Chayrigues H. , Merienne C. , Gaudemer A.
Published: April 2003

Variations in PMR‐15 composites properties could be due to differences in their chemical compositions occurring during the curing cycle. Variations in the composition of the PMR‐15 resin were studied for four different curing cycles, to determine the influences of parameters such as the heating rate or the presence of a temperature stage. The resin mixture was sampled at the same four different temperature points in each cycle and analyzed mainly by 1H‐ and 13C‐NMR. Quantitative analysis of the different chemical species were realized by deconvolution of NMR spectra. At a given temperature, the resin contains the same molecules but in proportions which depend on the curing conditions and which reflect differences in the chemical reactivity of the monomeric species. We have precisely defined the temperature ranges at which each of the key reactions (amidization, imidization, exoendo isomerization) occurs. An imine condensation product of NE and MDA has been identified and shown to be present in the resin mixture even at low temperature. As a result of this study, two possible causes of resin alteration during ageing can be put forward: the presence of nonimidized BTDE moieties and the endo‐exo isomerization reaction which will result in deformation and, possibly, microcracking, if reticulation of the end‐capped nadimides is not total. © 1994 John Wiley & Sons, Inc.
Synthesis of functional polymers bearing cyclic carbonate groups from (2‐oxo‐1,3‐dioxolan‐4‐yl) methyl vinyl ether
Authors: Nishikubo Tadatomi , Kameyama Atsushi , Sasano Mikio
Published: April 2003

(2‐Oxo‐1,3‐dioxolan‐4‐yl) methyl vinyl ether (OVE) was synthesized with high yield by addition reaction of glycidyl vinyl ether with carbon dioxide using tetrabutylammonium bromide (TBAB) as a catalyst. OVE was also prepared by reaction with β‐butyrolactone or sodium hydrogencarbonate in the presence of TBAB as the catalyst. Poly [(2‐oxo‐1,3‐dioxolan‐4‐yl) methyl vinyl ether] [P(OVE)] was obtained with high yield by cationic polymerization of OVE catalyzed using boron trifluoride diethyl ether complex in dichloromethane. Polymers bearing pendant 5‐membered cyclic carbonate groups were also prepared by radical copolymerization of OVE with some electron‐accepting monomers. Furthermore, addition reaction of P(OVE) with alkyl amines yielded the corresponding polymer having pendant 2‐hydroxyethyl carbamate residue with high conversions. © 1994 John Wiley & Sons, Inc.