bluuebunny/crossref_metadata_2025 huggingface dataset:
Die Kinetik der durch Acetationen‐Entladung angeregten radikalischen Polymerisation von Methylmethacrylat im nichtwäßrigen Medium
Authors: Olaj O. F. , Breitenbach J. W. , Sommer F.
Published: April 2003

Bei der Elektrolyse von Natriumacetat in Dimethylformamid(DMF)/Essigsäure (AcOH)/Methylmethacrylat(MMA)‐Gemischen, die auch ein Lösungsmittel für Poly‐MMA darstellen, kommt es unter geeigneten Bedingungen zwischen Platinelektroden lediglich an der Anode zur Polymerisation. Der Kettenstart wird dabei durch Folgeprodukte der anodischen Entladung der Acetationen ausgelöst. Die Polymerisationsgeschwindigkeit ist der vierten Wurzel der Stromstärke proportional; ab einer Stromdichte von etwa 2,5 mA/cm2 erfolgt allerdings keine weitere Zunahme der Polymerisationsgeschwindigkeit mehr. Dieser Punkt fällt ungefähr mit dem Beginn der anodischen Oxydation von DMF zusammen. Im untersuchten Temperaturbereich (10–45°C) ist die Bruttoaktivierungsenergie des Polymerisationsvorgangs (8,6 kcal/Mol) fast doppelt so groß wie bei photochemischer Anregung. Die bei den erhaltenen Polymerisationsgeschwindigkeiten auftretenden Polymerisationsgrade sprechen ebenso wie die Abhängigkeit der im System gebildeten Polymermenge P vom Volumen der Lösung \documentclass{article}\pagestyle{empty}\begin{document}${\rm V}\left( {{\rm P} \sim \sqrt {\rm V} } \right)$\end{document} für einen homogenen Verlauf der Polymerisation im gesamten Reaktionsraum.

Diese Befunde lassen sich mit Hilfe einer Modellvorstellung deuten, bei der eine unmittelbar an die Elektrode angrenzende Schicht als eigene „Reaktionszone”︁ aufgefaßt wird (Zweizonenmodell). In dieser Elektrodenzone stellt sich bei der Elektrolyse eine stationäre Konzentration cER an „Elektrodenzonen‐Radikalen”︁ ein; nur ein geringer Bruchteil dieser Radikale gelangt durch Desorption, Diffusion oder Reaktion mit dem Monomeren in das Lösungsinnere, das den eigentlichen Reaktionsraum darstellt. Nur dieser Bruchteil der primär an der Elektrode gebildeten Radikale, der sich dann innerhalb der Lebensdauer der Radikalketten homogen im gesamten zur Verfügung stehenden Elektrolysenvolumen verteilt, ist für die Bildung hochmolekularer Produkte verantwortlich.
Mechano‐chemisch synthetisierte Polychelate. I. Mechano‐chemische Komplexbildung durch Schwingmahlung von Polyäthylenterephthalat mit Eisenchlorid in Gegenwart von Äthylendiamin
Authors: Simionescu Cristofor , Oprea Cleopatra Vasiliu , Neguleanu Claudia
Published: April 2003

Es wurden zum erstenmal Komplexbildungsreaktionen von makromolekularen Liganden mit metallischen Chelatzentren unter mechano‐chemischen Aktivierungsbedingungen durchgeführt.

Als Liganden dienten Fragmente, die durch mechano‐chemische Polykondensation von Polyäthylenterephthalat mit Äthylendiamin erhalten wurden; als komplexbildendes metallisches Agens wurde dreiwertiges Eisenchlorid verwendet. Die Umsetzung verläuft unter den Bedingungen der Schwingmahlung von Polyäthylenterephthalat in Gegenwart von Diamin und von anorganischem Salz und führt zu thermostabilen, unschmelzbaren und unlöslichen Polymeren mit Halbleitereigenschaften.
Polymerisation of vinyl monomers by transition‐metal allyl compounds. IV. Molecular weight distribution of poly(methyl methacrylate)
Authors: Ballard D. G. H. , Dawkins J. V.
Published: April 2003

Molecular weights and molecular weight distributions of poly(methyl methacrylate) initiated by Cr(2‐methallyl)3 have been determined by gel permeation chromatography. The distribution is shown to broaden with polymerisation conversion, and it is suggested that this results from the formation of long chains having a high isotactic triad content. Number average molecular weights extrapolated to zero conversion are shown to depend largely on transfer processes. The experimental molecular weight distribution at zero conversion is shown to correspond to that expected from the polymerisation mechanism.
Studies on the swelling of crosslinked polymers of mono‐, di‐, tri‐, and poly(ethylene glycol) monomethacrylates in water and normal alcohols
Authors: Ore Svein , Kulvik Eigil , Ohr William , Zapffe Jan W.
Published: April 2003

From the equilibrium swelling of lightly crosslinked glycol monomethacrylate polymers in water and normal alcohols (C1 to C10) and in water‐alcohol mixtures it has been possible to draw conclusions regarding the molecular arrangements created by the specific interaction between polymer and sorbate molecules in these systems. The interaction has also been discussed in terms of the solubility parameter concept extended to systems in which hydrogen bonding is operative.
Stabile polyradikale mit stickoxid‐gruppen
Authors: Braun Dietrich , Hauge Sven
Published: April 2003

Die Herstellung und die radikalische Polymerisation von N‐(4‐Diphenylamino)‐acrylamid und N‐(4‐Diphenylamino)‐methacrylamid werden beschrieben. Durch Oxydation des Poly‐N‐(4‐diphenylamino)‐acrylamids mit Bleidioxid erhält man nicht das erwartete polymere Diphenylstickstoffradikal, sondern ein Polyradikal mit Diphenylstickoxidgruppen.
Analysis of optical rotatory dispersion of poly‐ and oligo(L‐lactate) by two‐term DRUDE equation
Authors: Matsuo Shunji , Iwakura Yoshio
Published: April 2003

Optical rotatory dispersion (ORD) and circular dichroism (CD) of poly(L‐lactate) were investigated and were compared with those of optically active oligo(L‐lactate),

prepared by the stepwise method. Two‐term DRUDE equation was applied to analyse the ORD curves using n‐π* and π‐π* transition bands as the critical wavelengths, Λ0 and Λ1. No drastic difference in ORD between poly(L‐lactate) and oligo(L‐lactate) was detected in chloroform and dioxane, which suggests that the polymer does not form any special conformation in these solvents. However, in acetonitrile it was found that the value of −A1/A0 (A1 and A0 are constants characteristic of π‐π* and n‐π* transitions of ester chromophores, respectively) of the polymer differed from that of the oligomer (n = 3).
A study of intramolecular reaction during linear polyurethane formation
Authors: Stepto R. F. T. , Waywell D. R.
Published: April 2003

The numbers of rings formed in the reactions of hexamethylene diisocyanate with two polyethylene glycols have been determined as a function of dilution and ratios of reactants. In this work the cryoscopic apparatus developed in the preceding paper has been utilised. It is found that more rings are formed (a) in dilute solutions, (b) with reactants of lower molecular weight, and (c) in reactions at equimolar concentrations. Some of the results may be interpreted approximately by means of JACOBSON and STOCKMAYER's theory. Values of the FLORY‐HUGGINS' interaction parameter χ have been determined from the cryoscopic data. They show a very marked dependence on the density of hydroxyl groups in the chain.
The alkaline hydrolysis of methyl methacrylate/isoprene copolymers. 2. Confirmation of the calculated copolymer sequence distributions by 220 MHz NMR spectroscopy
Authors: Bevington J. C. , Ebdon J. R.
Published: April 2003

Peaks in the 220 MHz NMR spectra of methyl methacrylate/isoprene copolymers may be used to determine the sequence distributions in the copolymers. Sequence distributions determined in this way are in good agreement with those calculated using reactivity ratios.
Studies on the structure of polyurethane elastomers. III. Characterization of linear polyurethanes by NMR‐spectroscopy: Components and molecular weight
Authors: Chokki Yasuo , Nakabayashi Masamitsu , Sumi Masao
Published: April 2003

The NMR method was applied to the analysis of linear polyurethanes and also for their molecular weight determination. The number‐average molecular weight can be calculated from the ratio of NMR absorption intensity corresponding to chain segments of polymers to that of end groups.
Metal halide and organometal halide catalyzed copolymerization and cyclocodimerization of acrylonitrile and butadiene
Authors: Kuran Witold , Pasynkiewicz Stanislaw , Florjańczyk Zbigniew
Published: April 2003

The effect of inorganic halides MX (M = Zn, Al, Ti, B; X = Cl, Br) and organometallic halides MRX (M = Zn, Al; R = CH3; X = Cl) of LEWIS acid type was studied with respect to the copolymerization and the cyclocodimerization of acrylonitrile and butadiene. The relative acid strength of these halides was established by IR studies of the acrylonitrile/halide complexes. In the presence of these LEWIS acids, acrylonitrile cyclocodimerizes with butadiene to give 4‐cyanocyclohexene the yield of which increases with acid strength, e.g., 100% for BCl3. Some of these acids give rise to the simultaneous formation of an acrylonitrile/butadiene (1:1) copolymer. As the acid strength is increased, the copolymer yield passes through a maximum to become nil at the highest acid strengths (TiCl4, BCl3). Unlike the inorganic halides, the organometallic halides MRX give rise to spontaneous copolymerization. A general mechanism of the reactions in the presence of MX and MRX is postulated to account for the data obtained.
Polymérisation et copolymérisation du sulfure de propylène amorcées par des systèmes dérivés du triéthylaluminium
Authors: Dumas P. , Spassky N. , Sigwalt P.
Published: April 2003

La polymérisation du sulfure de propylène amorcée par les systèmes binaires AIEt3/H2O conduit principalement à la formation de polymères amorphes de bas poids moléculaires. Dans certaines conditions, on peut obtenir également une petite fraction d'un tétramère cyclique cristallin de haut point de fusion. L'addition de tétrahydrothiophène au système AIEt3/H2O inhibe la formation du tétramère cyclique, pour laquelle l'intervention d'un mécanisme cationique a été proposé. Les amorceurs ternaires AIEt3/H2O/ROH permettent par contre d'obtenir des polymères de hauts poids moléculaires partiellement cristallins, analogues à ceux obtenus par amorçage avec le système ZnEt2/H2O.

Dans les copolymérisations du sulfure de propylène et du sulfure d'isobutène amorcées par les systèmes AIEt3/H2O (1:1) et BF3/Et2O, le sulfure de propylène est le monomère le plus réactif.
Vinyl polymerization. 280. Anionic polymerization of acryloyl‐ and methacryloyl verdazyls
Authors: Miura Yozo , Kinoshita Masayoshi , Imoto Minoru
Published: April 2003

1.5‐Diphenyl‐3‐(p‐methacryloyloxymethylphenyl) verdazyl (I), 1.5‐diphenyl‐3‐(p‐methacryloyloxyphenyl) verdazyl (II), and 1.5‐diphenyl‐3‐(p‐acryloyloxymethylphenyl) verdazyl (III) were synthesized and anionically polymerized with n‐butylmagnesium bromide or sodium naphthalene as an initiator to dark green polymers of a molecular weight of about 2300. III was polymerized with a catalytic amount of initiator, while I needed more initiator than the molar equivalent of the monomers suggesting the formation of intermediate metal salts of monomers and subsequent polymerization of the salts. More reactive double bond of III polymerized directly without the formation of the salt between stable free radical and organometallic compounds. Polymeric verdazyls contained up to 68% stable free radical.
Studies of the polymerization of vinyl compounds in the presence of metal salts. 7. Effect of nitric acid on the polymerization of acrylamide initiated by ceric salt
Authors: Narita Hiroshi , Okimoto Tomoyuki , Machida Seishi
Published: April 2003

The polymerization of acrylamide initiated by ammonium cerium(IV) nitrate was investigated. The rate was found to vary with concentration of nitric acid. One factor for the variation is the change of concentration of active species of ceric ion by the acid and another factor is the decrease in activity of acrylamide, because the equilibrium constant for the complex of acrylamide with ceric ion decreased with increasing concentration of acid. The rate of initiation was decided by the increasing of activity of ceric ion and by decreasing of that of monomer. The rate of termination was found to increase with increasing activity of ceric ion. From these results, the structure of the complex was proposed; the ceric ion is considered to be coordinated to carbonyl oxygen rather than double bond in acrylamide.
Reconstructive denaturation of proteins by sodium by sodium dodecyl sulfate. Circular dichroism of soybean trypsin inhibitor, papain and a mold protease
Authors: Jirgensons Bruno
Published: April 2003

Circular dichroism (CD) of solutions of soybean trypsin inhibitor (STI), papain, and an acid mold protease (from Rhizopus chinensis) was determined in the presence and absence of sodium dodecyl sulfate (SDS). The CD bands in the 240–320 nm spectral zone were almost completely eliminated by SDS. This indicated that the tertiary folding was disturbed and the restrictions imposed on the aromatic chromophores were largely removed. The CD bands in the far UV were modified by SDS in a manner that indicated increase of the α‐helix content in these proteins. This specific type of denaturation has been observed also on many other proteins. The term reconstructive denaturation is suggested for this type of denaturation in which the helix content of the polypeptide chain is enhanced by the denaturing agent.
A kinetic study of acrylamide polymerization initiated by 4.4′‐azo‐bis‐4‐cyanopentanoic acid in aqueous solution
Authors: Baer Michael , Caskey Jerry A. , Fricke Arthur L.
Published: April 2003

A dilatometer was constructed to study the free radical polymerization kinetics of acrylamide below 0.1 M monomer. The polymerization was initiated by 4.4′‐azo‐bis‐4‐cyano‐pentanoic acid in aqueous solution at 25°C.

The fkd value, calculated from dilatometric and viscometric data for a test with initial concentration [M] = 0.093 M and [I] = 2.09·10−3 M, was 2.81·10−8 sec−1. Comparison with an extrapolated literature value for kd at 25°C indicated an efficiency value, f, equal to 0.65. Both fkd and f were comparable in magnitude to results of other cited investigations.

The results of a 3/2 order dependency of polymerization rate on [M] substantiated the apparent tendency of acrylamide concentration exponents to increase above 1.0 below 0.1 M monomer. A cage effect theory was offered as an explanation for this phenomenon.
Diffusion of gases in poly(methyl methacrylate)
Authors: Patel V. M. , Patel C. K. , Patel K. C. , Patel R. D.
Published: April 2003

Diffusion of helium, oxygen, nitrogen, and carbon dioxide in poly(methyl methacrylate) has been studied. The data are analyzed employing the new modified time‐lag technique developed by PAUL and DIBENEDETTO. Different thermodynamic parameters have been evaluated and the mechanism of gaseous diffusion has been discussed.
Rheologische untersuchungen an polymethylmethacrylat‐Lösungen und ihre interpretation nach dem modell der netzwerk‐Lösung
Authors: Lederer K. , Schurz J.
Published: April 2003

Viskositätsmessungen an Lösungen von Polymethylmethacrylat in Toluol werden nach dem Modell der Netzwerk‐Lösung ausgewertet. Zum Vergleich wird für dasselbe System eine numerische Berechnung der von BUECHE angegebenen Beziehung durchgeführt; es ergibt sich im η0–M‐Verlauf kein Knick, sondern ein Übergang, dessen Breite unter anderem von dem Schlüpffaktor s abhängt. Der Vergleich von Rechnung und Meßdaten ergibt einen vernünftigen Wert des Segment‐Reibungsfaktors f0. Aus den Meßwerten wird weiter das kritische Molekulargewicht Mc ermittelt und daraus das scheinbare statistische Fadenelement A′m, das mit Werten aus anderen Messungen befriedigend übereinstimmt.
Etude de la cristallisation des polymères VIII. Phénomène d'adsorption à la surface des lamelles de polyoxyéthylènes de faible masse moléculaire
Authors: Mathis André , Thierry Annette , Terrisse Jean , Skoulios Antoine
Published: April 2003

On a étudié le gonflement de l'édifice lamellaire d'un polyoxyéthylène de faible masse moléculaire en présence de divers solvants. La technique employée est la diffraction des rayons X aux petits angles de BRAGG.

Lorsque les molécules du polymère sont terminées par des groupes OH, le gonflement est d'autant plus important que le solvant utilisé présente un coefficient plus élevé d'étalement sur l'eau et peut davantage former des liaisons hydrogène.

Lorsqu'on remplace les fonctions OH terminales par des fonctions Cl ou OCOCH3, le gonflement s'atténue de façon significative.
Preparation of polyarylates with methyl‐di(p‐carboxyphenoxymethyl)phosphine oxide acid chloride
Authors: Borissov Georgi , Sivriev Hristo
Published: April 2003

Polyarylates were prepared from methyl‐di(p‐carboxyphenoxymethyl)phosphine oxide (MCPO) acid chloride and bis‐phenols by the interphase polycondensation method
magnified image
The highest molecular weights were obtained at an MCPO acid chloride concentration of 0.1 mole·l−1 and a concentration of the bisphenol of 0.05 mole · l−1. Copolyarylates were also synthesized from 2.2‐bis(p‐hydroxyphenyl)propane, MCPO and terephthalic acid chloride employing different mole ratios of monomers. The homo‐ and copolyarylates obtained possess well expressed self‐extinguishing properties and enhanced thermostability.
Synthese neuer ungesättigter comonomerer und ihre copolymerisation mit acrylnitril
Authors: Bahr Ulrich , Wieden Horst , Rinkler Heinrich‐August , Nischk Günther
Published: April 2003

Zur Copolymerisation mit Acrylnitril wurden neue Monomere mit einer H2CC(R)CObzw. H2CC(CH3)C6H4‐Gruppe einerseits und einer tertiären Amino‐Gruppe, einem Pyridyl‐Rest, einer Carbonsäure‐hydrazid‐Gruppe CONHNRR′, einer Oxalsäure‐hydrazid‐Gruppe COCONHNRR′ oder einer Semicarbazid‐Gruppe NHCONHNRR′ andererseits hergestellt. Ein Teil dieser Verbindungen wurde durch Umsetzung mit Dimethylsulfat, p‐Toluolsulfonsäuremethylester oder cyclischen Sultonen in entsprechende quartäre Ammoniumsalze bzw. Sulfobetaine überführt. Durch Copolymerisation dieser Monomeren mit Acrylnitril wurden Copolymere mit verbesserter Anfärbbarkeit und erhöhter Wasseraufnahme erhalten.
Spectres de résonance paramagnétique électronique des catalyseurs de polymérisation à base de TiCl3. I. Etude expérimentale
Authors: Girard Y. , Che M. , Guyot A. , Chanzy H.
Published: April 2003

On a procédé à l'étude des signaux de résonance paramagnétique életronique (RPE) de catalyseurs de polymérisation industriels à base de TiCl3 avant et après attaque par le triisobutylaluminium (TIBA) en solution dans l'heptane. Selon la nature des échantillons, les spectres comportent un signal étroit à g = 1,94 et éventuellement un signal large à g = 1,84 ± 0,02. Ce dernier paraǐt caractéristique d'une attaque superficielle par l'eau atmosphérique. L'attaque par le TIBA provoque un processus d'extraction et de reprécipitation de composés du titane et une forte alcoylation de la surface, accompagnée par un dégagement important d'hydrocarbures. Elle modifie peu les caractéristiques du signal étroit et fait apparaǐtre, si elle reste modérée, de nouveaux signaux (g = 1,98).

Il n'y a cependant pas de corrélation entre ces signaux et l'activité catalytique du solide préalablement lavé et utilisé ensuite avec Al(C2H5)2Cl pour polymériser le propène.
Étude de la cristallisation des copolymères triséquencés poly‐ε‐caprolactone/polyoxyéthylène/poly‐ε‐caprolactone. II. Copolymères dont les séquences ont des longueurs voisines
Authors: Perret Rémi , Skoulios Antoine
Published: April 2003

On a étudié la structure et la cristallisation d'un copolymère triséquencé poly‐ε‐caprolactone/polyoxyéthylène/poly‐ε‐caprolactone, dont les séquences, toutes capables de cristalliser, ont des longueurs équivalentes.

Grǎce à la dilatométrie et à la diffractométrie selon DEBYE‐SCHERRER, on a montré que les deux types de séquences cristallisent effectivement et dans un ordre qui dépend de la température de l'expérience. On a défini trois domaines de température: au‐dessous de 51°C, c'est le polyoxyéthylène qui cristallise en premier; au‐dessus de 52°C, c'est au contraire la polycaprolactone qui cristallise en premier; entre 51 et 52°C enfin les deux séquences semblent cristalliser en měme temps.

A l'aide de la diffractométrie aux petits angles de BRAGG, on a montré que la structure du copolymère est lamellaire et correspond à l'empilement périodique et alterné de couches de polyoxyéthylène et de polycaprolactone. On a de plus établi que, dans la zone intermédiaire de températures de cristallisation, le système résulte de la juxtaposition de domaines entiers comportant des lamelles soit du type de celles obtenues au‐dessous de 51°C, soit du type de celles obtenues au‐dessus de 52°C.

En calculant les taux de cristallinité respectifs des deux séquences du copolymère, on a constaté que ceux‐ci ne sont élevés, et en tout cas comparables à ceux des homopolymères correspondants, que dans la mesure où les séquences considérées ont cristallisé avant les autres.

Dans une tentative de description plus détaillée de la structure, on a calculé les épaisseurs respectives des couches de polyoxyéthylène et de polycaprolactone, et, dans chacune d'elles, des sous‐couches de polymère cristallin et amorphe.

En étudiant par dilatométrie la fusion du copolymère, on a constaté que les deux types de séquences fondent indépendamment, d'abord les séquences de polyoxyéthylène, puis celles de caprolactone.

Dans une dernière partie, on a considéré enfin le phénomène de recuit. Par suite de la fusion précoce du polyoxyéthylène et de la lenteur extrěme de la polycaprolactone à recuire, le copolymère n'évolue guère par chauffage à température élevée.
The synthesis of diols based on the dimer of butadiene
Authors: Burgess F. J. , Cunliffe A. V. , Richards D. H.
Published: April 2003

It has been shown that the reaction of equimolar quantities of butadiene and epoxide with alkali metal in tetrahydrofuran results in the formation of the dimer diol

on subsequent hydrolysis. Yields up to 70% have been obtained with lithium metal, but with sodium the reaction is less efficient.
The thermal degradation of poly(oxycarbonylethylene) (poly‐β‐propiolactone)
Authors: Iwabuchi Susumu , Jaacks Volker , Galil Fahmy , Kern Werner
Published: April 2003

The thermal degradation of poly(oxycarbonylethylene) (poly‐β‐propiolactone) has been investigated within a temperature range of 180–220°C and under various pressures. The degradation begins with a considerable decrease in molecular weight, followed by an accelerating formation of acrylic acid. The reaction involves the following steps:

Random chain scission of polymer chains by typical ester pyrolysis with the formation of fragments one of which containing a carboxylic group the other one a CC‐double bond at the chain end (Eq. (1)).

Formation of the volatile acrylic acid by scissions at the chain end, the amount of acrylic acid or the weight‐loss increasing with the number of fragmentations (Eq. (2)).

Autocatalysed acidic cleavage of the polyester fragments into an α,β‐unsaturated ester and an acid as shown with low molecular model compounds (Eq. (8)).

Substitution of the labile α‐hydrogen atoms in poly(oxycarbonylethylene) by methyl groups—such as in poly(oxycarbonyl‐1,1‐dimethylethylene)—reduces the rate of degradation drastically. This observation together with the results obtained in the pyrolysis of the low‐molecular model compounds, ethyl β‐acetoxypropionate and β‐acetoxypropionic acid, support the postulated mechanism.
Kinetics and mechanism of the polymerization of cyclic acetals initiated by stable carbenium salts. II. Confirmation of the initiation mechanism for triphenylmethyl hexachloroantimonate in the polymerization of 1,3‐dioxolan
Authors: Penczek Stanisław , Kubisa Przemysław
Published: April 2003

The interaction of triphenylmethyl hexachloroantimonate (I) with 1,3‐dioxolan (II) gives the corresponding dioxolenium salt IV which decomposes into β‐chloroethyl formate (V) and antimon pentachloride (VI) (Eq. (2)) or acts as initiator by reacting with 1,3‐dioxolan (Eq. (3)). Triphenylmethyl tetrachloroantimonate does not initiate polymerization of 1,3‐dioxolan but forms exclusively β‐chloroethyl formate. SbCl5, formed according to Eq. (2), reacts with 1,3‐dioxolan to produce again the dioxolenium salt IV together with HCl and non‐initiating by‐products: SbCl3 and (CH3OCH2CH2O)n SbCl5hyphen;n, in proportions depending on the reaction conditions.

β‐Chloroethyl formate has been found to be present in the polymerization mixture at concentrations close to those calculated on the assumption that the reaction between the original initiator (I, IV, VI, triethyloxonium hexachloroantimonate or triphenylmethyl tetrachloroantimonate) and 1,3‐dioxolan as well as the further decomposition of IV go to completion.

All the initiators (In) give the same polymerization rates which are proportional to [In]0 in toluene solution and proportional to [In]20 in dichloromethane solution.

Considering the competitive consumption of the initiator and the formation of the true initiating species these results can be rationalized by the analysis of the kinetics according to the reaction scheme.

Polymerization has been found to be of first order in monomer and to proceed without an induction period. Thus, initiation is fast, in agreement with the previously measured rates of hydride transfer to the triphenylmethyl cation and the fast decomposition of the dioxolenium salt in the presence of 1,3‐dioxolan.
Zur copolymerisation von α‐methylstyrol und butadien. II. Das NMR‐spektrum der sequenzen mit zentraler butadieneinheit
Authors: Elgert K. F. , Seiler E. , Puschendorf G. , Cantow H.‐J.
Published: April 2003

Die 220‐MHz‐Protonenresonanzspektren von Copolymeren aus α‐Methylstyrol und Butadien wurden untersucht. Die Modellsubstanzen wurden in einer durch Lithiumbutyl initiierten Polyreaktion bei ‐75°C in Tetrahydrofuran hergestellt. Unter diesen Bedingungen wird das Butadien bevorzugt in 1,2‐Stellung verknüpft. Bei der Analyse des NMR‐Spektrums der seitenständigen Vinylgruppe wurde keine Aufspaltung durch Sequenzen unterschiedlicher Taktizität gefunden. Durch Verwendung von 2,3‐Dideuterobutadien gelingt die Deutung des Spektrums im Resonanzbereich der Methin‐ und Methylen‐Protonen durch Triaden und Pentaden mit zentraler Butadieneinheit. Die gemessenen Partialkonzentrationen stimmen mit den aus der Copolymerisationsgleichnng berechneten gut überein. Der Grad der 1,4‐Verknüpfung des Butadiens ist nicht konstant, sondern hängt von der α‐Methylstyrolkonzentration in der Ausgangsmischung ab.
Vibrational spectra of some new deuterated polypropyleness
Authors: Wolfsgruber C. , Cabassi F. , Tosi C.
Published: April 2003

The IR spectra of six atactic and five isotactic deuterated polypropylenes are reported. The vibrational assignment is discussed based on a careful mutual comparison of the spectra in addition to a comparison with those already known from the literature.
Studies of the polymerization of diallyl compounds. XVI. Copolymerizations of diallyl esters of aromatic dicarboxylic acids with methylallyl benzoate
Authors: Matsumoto Akira , Sasaki Hiromi , Oiwa Masayoshi
Published: April 2003

Radical copolymerizations of diallyl phthalate (DAP), diallyl isophthalate (DAI), and diallyl terephthalate (DAT) with methylallyl benzoate (MABz) have been carried out in bulk at 60°C, using benzoyl peroxide as initiator.

In the copolymerization of DAP with MABz the residual unsaturation of the copolymer decreased with increasing mole fraction of MABz in the feed. In the case of DAI it was nearly constant, regardless of the molar feed ratio, whereas with DAT it tended to increase with increasing mole fraction of MABz in the feed. These results were interpreted by considering the difference of the mode of cyclization in the case of DAP, DAI, and DAT.

The following monomer reactivity ratios γ1 (of the uncyclized radical), γc (of the cyclized radical) and γ2 (of the MABz radical) were estimated on the basis of the cyclocopolymerization mechanism. DAP: 0,84; 0,61; 1,08; DAI: 0,76; 0,52; 1,06. For the copolymerization of DAT with MABz the apparent monomer reactivity ratios based on the general copolymer composition equation were obtained as γ1 = 0,79 and γ2 = 1,06.
Vernetzte polymere mit spaltbaren netzbrücken. II. kinetik der vernetzenden copolymerisation
Authors: Braun Dietrich , Brendlein Wolfgang
Published: April 2003

Bei der Copolymerisation von Diolefinen mit Monoolefinen entstehen im allgemeinen vernetzte Polymere. In der vorliegenden Arbeit wird die Kinetik derartiger Copolymerisationen beschrieben. Es wird ein numerisches Rechenverfahren angegeben, das die Zahl der Vernetzungsstellen in Abhängigkeit vom Umsatz und von den Copolymerisationsparametern liefert. Die Ergebnisse werden anhand einiger Beispiele erläutert.
Fractionation of cellulose acetate by thin‐layer chromatography
Authors: Kamide Kenji , Manabe Sei‐Ichi , Osafune Etsuko
Published: April 2003

An attempt is made to evaluate the distribution of acetyle content (ACD) and of molecular weight distribution (MWD) of cellulose acetate by means of thin‐layer chromatography (TLC). A binary mixture of methylene chloride (MC)/methanol is useful for ACD evaluation, and ternary mixtures of MC/tetrahydrofuran (THF)/methanol and MC/acetone/methanol are suitable for evaluating MWD. The step‐wise composition method is powerful in eliminating a tailing effect as well as to improve the separation efficiency. For MC/THF (or acetone)/methanol (or butanol) a series of ridges is observed in the diagram of rate of flow (Rf)‐composition of the mixture. This can be explained reasonably in terms of variation of polarity of the mixture together with variation of solubility of the polymer in the mixture. Separation with respect to the acetyl content or molecular weight is due to the two different mechanisms: an adsorption‐desorption mechnism and a phase‐separation mechanism. Which plays the predominant role for a given TLC experiment depends on the mixture composition and the developing conditions i. e., mixtures having a methanol content less than 5–10% are mainly controlled by the adsorption‐desorption mechanism and mixtures with a methanol content higher than 50–60% by the phase‐separation mechanism.
The origin of the initiating activity of (C2H5)3O+PF for the polymerization of N‐vinylcarbazole
Authors: Turchi Gino , Matera Felice , Magagnini Piero L.
Published: April 2003

In the presence of (C2H5)3O+PF (1) N‐Vinyl carbazole (NVC) can polymerize rapidly and completely especially in methylene dichloride. A study of this polymerization, with 14C‐labelled (C2H5)3O+PF and with living polytetrahydrofuran as apparent initiators, has shown that oxonium ions are not responsible for the initiation. The true initiator is most probably PF5 formed by the decomposition of the salt. The necessary co‐initiator is provided by an impurity in the monomer. The initiation by a solution of living poly‐THF, containing PF−6 ions, is explained by the formation of traces of PF5 in a termination reaction of the THF polymerization.
Thermal analysis of poly(1,3,4‐oxadiazole‐2,5‐diyl‐1,4‐phenylene) and poly 1,3‐phenylene‐1,3,4‐oxadiazole‐2,5‐diyl‐1,4‐phenylene
Authors: Varma I. K. , Sambandam R. M. , Varma D. S.
Published: April 2003

Poly(1,3,4‐oxadiazole‐2,5‐diyl‐1,4‐phenylene) (I) and poly(1,3‐phenylene‐1,3,4‐oxadiazole‐2,5‐diyl‐1,4‐phenylene) (II) and its nitroderivative have been prepared by condensation polymerization using fuming H2SO4and different quantities of terephthalic acid (TA), isophthalic acid (IA), nitrophthalic acid (NA), and hydrazine sulphate (HS) respectively. Homopolymers of TA and HS, and copolymers of TA, IA, HS and TA, NA, and HS of different intrinsic viscosities were prepared by varying the reaction conditions. The polymer structures were investigated by visible range spectra, UV spectra, IR spectra and elemental analysis. The existence of poly(1,3,4‐oxadiazolediyl‐phenylene)‐ and poly(hydrazoterephthaloyl)‐structures was revealed by these studies. These polymers were thermally stable and most of them did not show any loss in weight below 360°C. The maximum weight loss was in the temperature range of 460–480°C. The activation energyEand the frequency factorAfor the thermal degradation were evaluated. Linear relationships betweenEand the intrinsic viscosity and between the “integral procedural decomposition temperature” and the intrinsic viscosity were observed. The polymers I showed a higher stability than the copolymers II of similar molecular weights.
Vinyl polymerization by metal complexes, 10. Initiation by polyvinylamine–copper (II) chelate
Authors: Inaki Yoshiaki , Kimura Keiichi , Takemoto Kiichi
Published: April 2003

The polymerization of acrylonitrile, methyl methacrylate and styrene initiated by copper(II) chelates was studied in the prescence of carbon tetrachloride. A polymeric amine and a monomeric diamine, that is, polyvinylamine and 1,3‐diaminopropane, were chosen as ligands. The activity of the polymeric chelate was found to be specific and higher than that of the 1,3‐diaminopropane chelate. It was compared with that of the 1,3‐diaminopropane chelate, by changing pH values of the system and the reaction temperature. Plots of conversion against pH afforded a peak at pH 8, and trends of increasing of conversion were observed above pH 10. The apparent activation energy of the polymerization initiated by the polymeric chelate was higher than the apparent activation energy of the polymerization initiated by the 1,3‐diaminopropane chelate. The fact was attributed to the difference of their chemical structures.
Radical formation during the tensile failure of polymer fibers
Authors: Crist B. , Peterlin A.
Published: April 2003

Bond rupture associated with the tensile deformation of oriented Nylon 6 has been studied by electron spin resonance (ESR). Two samples were investigated, a single monofilament (“bristle”) and a commercial low twist yarn. Experiments with the monofilament show that tensile deformation has substantial irreversible effects on the free radical concentration observed at failure, but no effect on the ultimate properties of the fiber. It was also demonstrated that the stress‐strain behavior of the yarn is quite different from that of the fibers near the ultimate extension. These present experiments raise serious questions as to the correctness of previous reports in which the bond breakage observed by ESR is assumed to uniquely determine the deformation and fracture process.
Polymerisation von methacrylsäure‐methylester mit eisenchloriden als initiatoren in sauren wäßrigen lösungen
Authors: Jovanović Slobodan M. , Novaković Miroljub
Published: April 2003

Der Einfluß von anorganischen Salzen auf die Polymerisation von Vinylmonomeren in wäßrigen und nichtwäßrigen Lösungsmitteln ist von mehreren Autoren untersucht worden1–4. Dabei wurde gezeigt, daß Eisen(III)‐chlorid die kinetische Kette durch einen Einelektronen‐Übertragungsprozeß abbrechen kann.

Es ist auch bekannt, daß man Eisen(III)‐salze, wie Eisen(III)‐chlorid, als Photosensibilisatoren für die Polymerisation von Methacrylsäure‐methylester5,6in Wasser oder von Acrylnitril in γ‐Butyrolacton7benutzen kann.
Metallkomplexe mit polymeren liganden, 3. Übergangsmetallkomplexe mit poly(2‐pyridyläthylen) [poly(2‐vinylpyridin)]
Authors: Biedermann Hans‐G. , Griessl Erika , Wichmann Klaus
Published: April 2003

Ataktisches Poly(2‐pyridyläthylen) [Poly(2‐vinylpyridin)] bildet mit Übergangsmetallverbindungen in Äthanol die folgenden Komplexe:

[Mt(II)L2(C7H7N)2]n(1b, 1c), [MtJ2(C7H7N)3]n(2b, 2c), [NiJ2(C7H7N)4]n(3b), [FeCl2(C7H7N)2]n(1a), [CoCl2(C7H7N)3]n(2a) und [FeCl3(C7H7N)2]n(4), Mt = Co, Ni. L = Acetylacetonat. Das Koordinationsverhalten des Poly(2‐pyridyläthylens) und die IR‐Spektren werden diskutiert.
Vinyl polymerization, 311. Synthesis and polymerization of 2‐bromoethoxyphenoxyphosphoryl methacrylate
Authors: Doiuchi Tooru , Nakaya Tadao , Imoto Minoru
Published: April 2003

2‐Bromoethoxyphenoxyphosphoryl methacrylate (5) was synthesized by the reaction of 2‐bromoethyl phenylchlorophosphonate (3) with silver methacrylate and then polymerized by a radical initiator. The resulting polymer was soluble in DMF, but insoluble in other organic solvents. The hydrolysis of the polymer with sulfuric acid led to the corresponding poly(methacrylic acid) with a molecular weight of Mn=4,4·105 (Pn=5,1·103). 5 was copolymerized with acrylonitrile and the monomer reactivity ratio was determined: r1 = 2,20, r2=0,27.
Charge‐transfer complexes of poly(N‐vinylcarbazole) with organic electron acceptors
Authors: Enomoto Takamichi , Hatano Masahiro
Published: April 2003

Poly(N‐vinylcarbazole) and its monomeric analog, i.e., N‐ethylcarbazole, act as donors in charge‐transfer complex formations with such electron acceptors as 2,3,5,6‐tetracyano‐1,4‐dimethylene‐2,5‐cyclohexadien‐1,4‐diylidene, tetracyanoethylene and 2,4,5,7‐tetranitro‐9‐fluorenone. The formation constants of the charge‐transfer complex of N‐ethylcarbazole with the electron acceptors are higher than those of poly(N‐vinylcarbazole) with the same electron acceptors. In order to clarify the polymer effect on these formation constants, poly(N‐vinyl carbazole)s, prepared by two types of polymerizations, are fractionated using a gel permeation chromatography technique, and the fractionated polymers are used for the measurements of the formation constants of the charge‐transfer complexes with various sorts of electron acceptors. The relation between charge‐transfer complex formation and molecular weight of the polymer is discussed in terms of the formation constant and the thermodynamic parameters.
Vinyl polymerization by metal complexes, 11. Formation of polyvinylamine‐copper(II) chelates
Authors: Kimura Keiichi , Inaki Yoshiaki , Takemoto Kiichi
Published: April 2003

In order to clarify the mechanism of catalysis of polyvinylamine‐copper(II) chelates on the initiation of vinyl polymerizations, stability constants of these chelates were measured by applying a modification of BJERRUM'S method, and each concentration of the chemical species was estimated on the basis of the chelate theory. From these results, the activity of the polyvinylamine‐copper(II) chelates for the polymerization of acrylonitrile and methyl methacrylate at different pH values was discussed.
Preparation of a novel polyoxime and reversible uptakes of molecular oxygen and carbon monoxide by its metal complexes
Authors: Kim Sung Jho , Takizawa Takeo
Published: April 2003

Polyketones with carbonyl groups in the polymer backbone (ethylene‐carbon monoxide copolymer) have been converted into a novel polyoxime by means of C‐nitrosation of the methylene groups and oximation of the carbonyl groups. The polyoxime is considered to be composed largely of 1,2‐bis(hydroxyimino)trimethylene units. From the polyoxime and divalent Fe‐, Co‐, or Ni‐salts, polymeric metal chelate complexes were prepared which are capable of combining reversibly with molecular oxygen and, especially the Fe‐complex, also with carbon monoxide.
Influence of the structure of cobalt(III)‐poly(4‐vinylpyridine) complexes on the electron‐transfer reaction
Authors: Tsuchida Eishun , Karino Yukio , Nishide Hiroyuki , Kurimura Yoshimi
Published: April 2003

Cobalt(III)‐complexes having a polymeric ligand, cis‐[Co(en)2PVPCl]Cl2, cis‐[Co(trien)‐PVPCl]Cl2, cis‐[Co(en)2PVPBr]Br2, cis‐[Co(en)2PVPN3]Cl2 and cis‐[Co(en)2QPVPCl]Cl2 (where PVP = poly(4‐vinylpyridine) and QPVP = partially quarternized PVP) were prepared and their reduction with ferrous sulfate was studied. Complex formation with QPVP was shown to be affected by steric factors such as the degree of polymerization and the bulkiness of the quaternizing agents, but the quarternization showed only a small steric influence on the reduction kinetics. The order of the reduction rate of cis‐[Co(en)2PVPX]2+ with respect to the bridging ligand X is N3 > Cl > Br, and the reduction rate of cis‐[Co(en)2PVPCl]2+ is higher than that of cis‐[Co(trien)PVPCl]2+. The effects of bridging and non‐bridging ligands in the reduction of polymer complexes were the same as those for the monomeric analogues.
Untersuchungen zur Reaktionsfähigkeit statistisch verteilter Estergruppierungen in Copolymeren aus Styrol und Acrylsäureestern
Authors: Böhmer Volker , Sauerbrey Hans‐Erich , Kämmerer Hermann
Published: April 2003

Die Aminolyse der ortho‐ und para‐Nitrophenylester von Propionsäure, Isobuttersäure, 4‐Phenylbuttersäure und 4‐Phenylvaleriansäure sowie von Copolymeren aus Styrol und geringen Mengen Acrylsäure wurde mit Butylamin in Dioxan untersucht. Bei großem Aminüberschuß reagieren die niedermolekularen Ester streng nach erster Ordnung, wobei die Reaktionsgeschwindigkeit durch Zugabe von Polystyrol nicht beeinflußt wird. Für Copolymere, deren Reaktionsgeschwindigkeit deutlich geringer ist, erhält man dagegen keine Beziehung erster Ordnung, obwohl die Anfangsgeschwindigkeit der Gesamtkonzentration der Estergruppen direkt proportional ist. Bei den Copolymeren erhält man annähernd die gleichen Aktivierungsenergien wie bei den niedermolekularen Modellestern und ebenfalls eine lineare Abhängigkeit der Reaktionsgeschwindigkeit von der Aminkonzentration. Für die Ergebnisse werden zwei unterschiedliche Erklärungen diskutiert.
Complexes à transfert de charge macromoléculaires dérivés de la phénothiazine: Propriétés photochromes
Authors: Gebus Bernard , Knoesel Roger
Published: April 2003

De nouveaux dérivés de la phénothiazine (1a) ont été préparés: la méthyl‐10 vinyl‐3 phénothiazine (1c), le poly[(phénothiazin‐3 yle)‐1 éthylène] (3a) (poly(vinyl‐3‐phénothiazine)) et des copolymères du méthacrylate de méthyle et de la vinyl‐2‐phénothiazine (2). Les propriétés des complexes à transfert de charge, formé par ces polymères et copolymères avec quelques accepteurs d'électrons, sont décrites. En particulier, les propriétés photochromes de certains complexes de la phénothiazine (1a) sont conservées, lorsque le groupe phénothiazinyle est introduit dans un milieu macromoléculaire. Les mécanismes des réactions photochimiques et leurs cinétiques ont été étudiées pour les sytèmes suivants: copolymère méthacrylate de méthyle/vinyl‐2 phénothiazine + accepteur en solution et sous forme de films; phénothiazine + accepteur dispersés dans une matrice solide de poly(méthacrylate de méthyle).
The addition halogenation of poly(1‐alkenylene)s, 5 X‐ray crystal structures of (RS)‐1,2,5,6‐tetrachlorohexane and (RRSS)‐2,3,6,7‐tetrachlorooctane
Authors: Bassi Ivano W. , Scordamaglia Raimondo
Published: April 2003

The high melting and most easily crystallizable products of the isomer mixtures obtained by addition chlorination of 1,5‐hexadiene and cis,cis‐2,6‐octadiene were found, by X‐ray analysis, to be the meso stereoisomers (RS)‐1,2,5,6‐tetrachlorohexane (TCH) and (RRSS)‐2,3,6,7‐tetrachlorooctane (threo‐disyndiotactic structure) (TCO) respectively.

The carbon atoms in both structures are in a nearly planar zigzag, while the side chlorine atoms are in a gauche position in respect of the carbon atoms. These molecular structures are compared with those of the crystalline chain segments obtained by addition chlorination of cis and trans poly(1‐alkenylenes). The crystals of TCH are monoclinic, space group P21/n, with Z=2 in a unit cell having dimensions: a=9,02±0,03, b=10,09±0,03, c=5,23±0,02 Å β=100°12′±20′.

The crystals of TCO are monoclinic, space group P21/n, with Z=2, in a unit cell of dimensions: a=10,97±0,03, b=8,66±0,02, c=6,27±0,02 Å, β=101°55′±20′. The X‐ray analysis has been performed with a Stoë‐automated Weissenberg camera. The structures have been refined by least‐square techniques to R=0,06 for 1076 reflections in the case of TCH and R=0,078 for 973 reflections in the case of TCO.
Polychalkone, 5 Untersuchungen über elektrische eigenschaften wärmebeständiger polychalkone
Authors: Rusu Gheorghe I. , Oleinek Heinz , Zugrǎvescu Ion
Published: April 2003

In der vorliegenden Arbeit wird über die Temperaturabhängigkeit der elektrischen Dunkelleitfähigkeit von Preßlingen aus den Polychalkonen 1a‐c und 2a,b berichtet. Es wird gezeigt, daß die elektrischen Eigenschaften nach einer Wärmebehandlung sowohl an der Luft als auch im Vakuum reproduzierbar sind und die Leitfähigkeit mit zunehmender Temperatur wächst, woraus folgt, daß die untersuchten Verbindungen Halbleiter sind. Die für die Aktivierungsenergie (im Gebiet der Eigenleitfähigkeit) gefundenen Werte variieren zwischen 1,45–2,25 eV/mol. Die enge Beziehung zwischen diesen und der chemischen Struktur wird diskutiert.
Investigation of the structure of 1,3,5‐trioxane—1,3‐dioxolane copolymers
Authors: Holdsworth Peter J. , Fischer Erhard W.
Published: April 2003

The temperature dependences of the absolute small angle X‐ray scattering powers and of the unit cell spacings of a series of 1,3,5‐trioxane—1,3‐dioxolane copolymers were measured. From a comparison of these data and of the specific volume values measured by Wilski it is concluded that values of crystallinity calculated in a conventional manner provide meaningful parameters when discussing the microstructure of these materials.

The measurements were made on annealed samples. At temperatures below the original annealing temperatures changes in small angle scattering power, long periods and crystallinities of the samples were observed. These changes were reversible with temperature and were too large to be explained by thermal expansion. It is concluded that the copolymers display the phenomenon known as partial melting. Possible structural explanations of this effect are examined.
Influence of polymolecularity on the second virial coefficient of poly(α‐methylstyrene)s in toluene
Authors: Elias Hans‐Georg , Bellido José , Bareiss Rolf E.
Published: April 2003

Anionically polymerized poly(α‐methylstyrene)s were mixed together to give Schulz‐Flory and logarithmic normal distributions with a weight average molecular weight of 80 000 g mol−1each. The second virial coefficients from light scattering in toluence at 25°C were more or less independent of the polymolecularity. The second virial coefficients from osmotic pressure measurements increased however strongly with increasing polymolecularity for mixtures with logarithmic normal distribution, whereas those for Schulz‐Flory distributions decreased.
Über Polyarylenalkenylene und Polyheteroarylenalkenylene, 4. Synthesen und Charakterisierung von Poly(2,7‐fluorenylenvinylenarylenvinylen)en und einigen dazugehörigen Oligomeren
Authors: Kossmehl Gerhard , Hatscher Karl‐Heinz , Manecke Georg
Published: April 2003

Mit Hilfe der Wittig‐Reaktion des 2,7‐Fluorendicarbaldehyds (1) mit „Mono‐ und Bis‐Wittig‐Salzen”︁ der Benzol‐ und Thiophenreihe wurden einige Poly(2,7‐fluorenylenvinylenarylenvinylen)e (3a–c) sowie einige dazugehörige Oligomere hergestellt. Die Wittig‐Reaktion des 2‐Fluorencarbaldehyds (6) mit „Mono‐ und Bis‐Wittig‐Salzen”︁ ergab eine weitere Reihe von Oligomeren. Die Struktur der erhaltenen Verbindungen wurde durch Elementaranalyse, IR‐ und Elektronenspektren – die der Oligomeren zusätzlich durch Massenspektren – bestätigt. Ferner wurde die elektrische Leitfähigkeit aller Polymerer und Oligomerer sowie der thermooxidative Abbau der Polymeren und einiger Oligomerer untersucht.
Untersuchungen über Poly(arylenvinylen)e, 9. Zusammenhang zwischen der chemischen Struktur und der photoelektrischen Empfindlichkeit von Polyxylylidenen
Authors: Hörhold Hans‐Heinrich , Opfermann Johannes
Published: April 2003

An einer Reihe verschieden substituierter und isomerer Poly(arylenvinylen)e (Polyxylylidene) wurde gefunden, daß bei den undotierten Polymeren zwischen der optischen Anregungsenergie Eopt und der photoelektrischen Empfindlichkeit JPh der Zusammenhang (1) besteht.

Diese Beziehung wird auf der Grundlage einer photochemischen Ionisation der Makromoleküle diskutiert.
Untersuchungen von polymeren im massenspektrometer, 5. Fragmentierungsreaktionen oligomerer oxy‐ und thio‐1,4‐phenylene
Authors: Montaudo Giorgio , Przybylski Michael , Ringsdorf Helmut
Published: April 2003

Als Modellverbindungen zur Differenzierung von thermischen und elektronenstoßinduzierten Abbaureaktionen von entsprechenden Polymeren im Massenspektrometer wurden die Fragmentierungsreaktionen oligomerer 1,4‐Phenylene mit Sauerstoff‐, Schwefel‐ und Disulfidbrücken sowie eine Reihe alternierender Co‐oligomersysteme untersucht.

Bei verringerter Ionisationsenergie (15 eV) treten in den Massenspektren aller unzersetzt flüchtigen Oligomeren die Molekülionen als intensivste Peaks auf, so daß–bei strukturell gleichen Polymeren–eine eindeutige Identifizierung von thermischen Abbauprodukten erwartet werden kann.

In Abhängigkeit von den Brückenatomen werden charakteristische Unterschiede in den Intensitäten der durch “α‐Spaltung” gebildeten elektronenstoßinduzierten Fragmente gefunden.