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IUPAC recommendations on source-based nomenclature for single-strand polymers have so far addressed its application mainly to copolymers, non-linear polymers and polymer assemblies, and within generic source-based nomenclature of polymers. In this document, rules are formulated for devising a satisfactory source-based name for a polymer, whether homopolymer or copolymer, which are as clear and rigorous as possible. Thus, the source-based system for naming polymers is presented in a totality that serves as a user-friendly alternative to the structure-based system of polymer nomenclature. In addition, because of their widespread and established use, recommendations for the use of traditional names of polymers are also elaborated.

Summary The Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, provides training of young scientists, mainly from economically disadvantaged countries, in the form of a 10-month programme under the auspices of UNESCO and IUPAC named “UNESCO/IUPAC Postgraduate Course in Polymer Science”. The programme consists primarily of a research-project work under supervision by senior researchers and also of lectures, seminars and language courses. In this paper, the achievements of the 18 completed academic years of the Course are summarised, and the progress of the current run is reported. For those who become interested in the future runs, practical advice is given.

This document defines terms relating to the properties of individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers. In the section on polymer solutions and amorphous bulk polymers, general and thermodynamic terms, dilute solutions, phase behaviour, transport properties, scattering methods, and separation methods are considered. The recommendations are a revision and expansion of the IUPAC terminology published in 1989 dealing with individual macromolecules, macromolecular assemblies, and dilute polymer solutions. New terms covering the principal theoretical and experimental developments that have occurred over the intervening years have been introduced. Polyelectrolytes are not included.

This document provides some basic rules and guidelines regarding the use and creation of abbreviations for the names of polymers. An extended list of currently used abbreviations for polymers and polymeric materials is appended.

For several decades, the relation between the contraction factor of radius of gyration for branched macromolecules, g, and that of intrinsic viscosity, g′, has been presented as g′ = ge. The value of e was assumed to be constant for branched macromolecules of a certain type, such as stars, or combs, or statistically branched macromolecules. Experimentally determined values of e, however, turn out in the majority of cases to be molecular-weight dependent. The present study shows that molecular-weight-independent values of e can be expected only for a plurality of molecules with identical architecture. By branched molecules with identical architecture we mean molecules in which with varying degree of polymerization the ratios of the degrees of polymerization of all sub-chains remain constant, irrespective of the integral degree of polymerization of individual molecules. Also, it has been demonstrated that the ratio of intrinsic viscosities of a linear and a branched polymer molecule having the same hydrodynamic volume, [η]l,V/[η]b,V

The nonuniformities of graft (co)polymers have been analyzed using the probability generating functions and their moments. The nonuniformity is described by ratios of averages of molecular weights ...

Synthesis, characterization, and reactivity of new allyl cyclopentadienyl molybdenum(II) compounds [(η3-C3H4R1)(η5-C5H3(R2)2)Mo(CO)2] (R1 = H, COOMe; R2 = COOMe, CONHtBu) are reported. Although these compounds are structural analogues of [(η3-C3H5)(η5-Cp)Mo(CO)2], their reactivity is very different. While protonation of [(η3-C3H5)(η5-Cp)Mo(CO)2] gives a cationic cyclopentadienyl complex, the presented compounds give cationic allyl complexes [(η3-C3H4R)Mo(CO)2(NCMe)3][BF4] (R = H, COOMe) or stable cationic allyl cyclopentadienyl complexes. The theoretical calculations have shown that this behavior is a result of high affinity of the functional groups in the cyclopentadienyl ligand toward protonation.

A series of samples of linear aromatic polyester of 3-phenylglutaric acid and bisphenol A was prepared with molecular weights ranging from 14 700 to 92 700. The polymers were characterized by size exclusion chromatography with triple light-scattering, viscosity, and concentration detection. Hydrodynamic parameters of the chain were determined using the theory of Yoshizaki, Yamakawa, and Nitta modified by Bohdanecký and Netopilik. The chain parameters are a useful reference in the study of aromatic hyperbranched polyesters.

This document defines terms related to the structure and processing of inorganic, polymeric, and inorganic-organic hybrid materials from precursors, through gels to solid products. It is divided into four sections - precursors, gels, solids, and processes - and the terms have been restricted to those most commonly encountered. For the sake of completeness and where they are already satisfactorily defined for the scope of this document, terms from other IUPAC publications have been used. Otherwise, the terms and their definitions have been assembled in consultation with experts in the relevant fields. The definitions are intended to assist the reader who is unfamiliar with sol-gel processing, ceramization, and related technologies and materials, and to serve as a guide to the use of standard terminology by those researching in these areas.

Stockmayer's classical theory of statistical branching of polymers, as modified by Thurmond and Zimm, and subsequently by Kilb, has been used to describe the evolution of the distribution of the degrees of polymerization with conversion up to the gel point in the copolymerization of a vinyl monomer with a small amount of a divinyl monomer. The weight fractions of molecules with a particular number of branch points per molecule, the averages of the degrees of polymerization of these molecules, and some other characteristics were calculated as functions of a complex variable—the branching parameter γ, including the composition of the monomer mixture, relative reactivities of the individual types of double bonds, and conversion. From these calculations, a few general conclusions on the behaviour of the model system can be drawn. The conclusions are likely to be qualitatively valid also for systems not strictly conforming to the model. Copyright © 2005 Society of Chemical Industry

The determination of the interdetector volume (IDV) in size-exclusion chromatography (SEC) of polymers with dual multiangle light-scattering/concentration detection based on the s-detection is demonstrated. By s-detection the determination is meant of local molecular mass from a known relation between molecular mass and radius of gyration, obtained from the angle dependence of the intensity of scattered light. IDV is found basing on the stipulation of equal slope of local calibrations found by the dual light-scattering/concentration detection, referred to as the w- and s-detection. As the s-detection uses just the light-scattering detector and, therefore, is independent of the value of IDV, this quantity can be found by searching for its value that gives the local calibration dependence obtained by the dual detection closest to that determined independently by the s-detection.

The evaluation of the size-exclusion chromatography (SEC) concentration elution curves by means of a calibration dependence obtained in a given SEC set for a polymer different from the polymer to be analyzed results in an error in the determination of both molecular weight and molecular-weight distribution (MWD). The problem is analyzed assuming the validity of the universal-calibration concept. The differences between the true and apparent values of molecular weight, MWD and Mw/Mn depend on and are expressed in terms of the parameters of the Mark–Houwink–Kuhn–Sakurada equation, describing the molecular-weight dependence of intrinsic viscosity, for the polymer to be analyzed and the polymer used for calibration. The differences in molecular weight and the Mw/Mn ratio are typically tens of percent and, in extreme cases, can amount up to a factor of three for molecular weight and a factor of two for the Mw/Mn ratio.

Copolymers of aniline and p-phenylenediamine were prepared by joint chemical oxidation of these chemicals with ammonium peroxydisulphate in aqueous medium. The temperature and frequency dependences of the impedance and permittivity of copolymers were measured. The exponential dependence of resistivity on aniline content was observed.

The forms of polyaniline, viz. pernigraniline, emeraldine and leucoemeraldine, their mutual transformations and their roles in the chemical polymerization of aniline, are discussed. Absorption spectra of its various protonated forms and corresponding bases are reported. A simple reaction scheme is proposed to account for the colour and acidity changes during polymerization.

Phase behavior of a hydrogenated styrene/isoprene diblock copolymer in a dimethylformamide/methylcyclohexane demixing-solvent pair has been studied. At a fixed copolymer concentration (1% w/v), the scheme of phase behavior (temperature vs. mixed-solvent composition) of the system has been found to be complex, with several areas where various supramolecular structures are spontaneously formed. In a particular area of the scheme, a multistep demixing-solvent fractionation of the copolymer has been performed. The resulting fractions have been characterized and the data used to construct integral distribution functions of copolymer molar mass and copolymer composition. These functions have been compared with those obtained by a previously reported light-scattering characterization of the whole, unfractionated, nonhydrogenated precursor of the copolymer © 1993 John Wiley & Sons, Inc.

Micellization of di- and triblock copolymers, poly(methacrylic acid)-block-polystyrene and poly(methacrylic acid)-block-polystyrene-block-poly(methacrylic acid), varying in molecular weight and composition, has been studied by static and dynamic light scattering, and sedimentation velocity. Micelles with polystyrene cores were prepared in water-dioxane mixtures, rich in dioxane, and transferred into water-rich mixtures, water, and aqueous buffers via stepwise dialysis. It has been shown that, in dioxane-rich mixtures, the micellar system was in dynamic equilibrium, while in water-rich solvents, water, and aqueous buffers the micellization equilibrium was frozen and micelles behaved like autonomus particles. Under certain conditions, micelles were accompanied by independent large particles. This phenomenon, known from other micellar systems as an "anomalous micellization", is discussed.

Polystyrene-block-poly(ethylene-co-propylene) solutions in decane have been investigated by dynamic and static light scattering. The dissolution of the diblock copolymer in a solvent, which is selective of aliphatic blocks, yields well-defined metastable micellar structures. These structures are converted into equilibrium micelles on heating and change into frozen micelles when cooled. A similar pattern is observed also in dioxane, which is a selective solvent for polystyrene blocks.

The synthesis of branched poly(methyl methacrylate) is described. The method used is based on an anionic technique with initiation by enolate ions. details of product characterization are included.

The molecular weight distribution functions of polystyrene degraded by shear stress in isopropylphenyl phosphate solution were compared with the calculated ones, obtained by assuming that up to a certain distance from each chain end the probability of bond scission is zero. Two phenomenological models were proposed for the probability of degradation in the central part of the chain. A comparison with experimental data suggests that the probability of degradation increases towards the center of the chain. Branched fractions formed by degradation in the presence of air were found to be present by the GPC method with on-line viscometric detection.

Two different units have been incorporated into polymer backbones to provide sites for potential anionic grafting reactions. In the first case, the sites were provided by p-vinylacetophenone residues, and the technique attempted involved the addition of polystyryl anions. In the second case, the functional sites were p-isopropenylstyrene residues, and these were used as initiating centres, from which grafts of poly(methyl methacrylate) were grown by means of anionic polymerisation initiated by butyllithium. Only the second method was met with success.

A new source-based nomenclature system is described which indicates that a particular polymer has been chemically modified. A connective within the name of a polymer, -mod-, is introduced for this purpose as in poly((A)-mod-(B)). The system is intended to be used in accordance with source-based naming of polymers but also provides for the use of structure-based names when it is unavoidable. It embraces: (1) modification of a constitutional unit into another, the unique structure of which is known; and (2) a more general modification of a constitutional unit resulting in any one of a number of possible structures. In addi- tion, a new symbol, ∼ > , is proposed for use in graphic representations of the structure of modified polymers.

A new method suitable for computer treatment was suggested for the evaluation of data obtained by light scattering from polymer solutions containing microgel. The method is based on the assumption of bimodal molar mass distribution and requires no additional data and/or restrictions. The accuracy of the present method was compared with that of other evaluation procedures (suggested by Lange, Gruber and Schurz, Strazielle, and Kratochvil) using model mixtures consisting of two polymers differing by 2 to 3 orders of magnitude in molar mass. The values of molecular parameters (Mw,1, Mw, z2, (rz,12)1/2, (rz,22)1/2) obtained by the present method are in general more reliable then those calculated by means of the other evaluation procedures.

Possibilities offered by classical precipitation fractionation in the preparative separation of polymer admixtures from block copolymers and in an estimate of the polydispersity in molar mass and of the heterogeneity in chemical composition of block copolymers have been examined. A mixture of a two-block copolymer, polystyrene-block-polyisoprene, with polystyrene was separated in the systems cyclohexane/1-propanol and 1,4-dioxan/1-propanol, and a mixture of three two-block styrene-isoprene copolymers having different chemical composition was fractionated in the system benzene/methanol. In the cyclohexane/1-propanol system, two commercial samples of three-block copolymers polystyrene-block-poly(ethene-co-butene)-block-polystyrene and their mixture were fractionated. The results showed that the polydispersity and chemical heterogeneity thus estimated are much lower than the real ones, especially due to the colloid properties of block copolymers.

One of the characteristic features of copolymers is their chemical heterogeneity. Examples are given of the dependence of conversion heterogeneity in the chemical composition of random copolymers on the initial composition of the monomer mixture, along with typical examples of the differential distribution functions of chemical composition. The maximum attainable values of the conversion heterogeneity parameter have been calculated depending on the copolymerization parameters. The conditions are discussed under which copolymers may acquire chemical heterogeneities high enough to be perceived or determined by fractionation or light scattering. Limits are estimated beyond which the chemical heterogeneity becomes undetectably low and the copolymers can be regarded as chemically homogeneous.

In aqueous KSCN solutions the salt is preferentially desorbed from the domain of gelatin molecules, similarly to synthetic polyelectrolytes. Light-scattering measurements in gelatin solutions in 0,5 M KSCN and in a single solvent (formamide) show that both solvents are suited for the molecular characterization of gelatin at room temperature. Neglecting the effect of selective sorption in salt solutions does not cause any considerable error in the molar mass determination of gelatin.

The refractive index increments of linear and branched polyethylene were determined for several solvents and various wavelengths (403, 436, 546, and 633 nm), mainly at 135°C. Differences were observed between values for linear and branched samples. Data obtained in this investigation are compared with the reported ones.

Dilute solutions of a three-block styrene-butadiene-styrene copolymer in the mixed selective solvent tetrahydrofuran/allyl alcohol exhibit a more or less pronounced turbidity. Sedimentation analysis and light scattering reveal that these solutions contain two components, namely, a molecularly dissolved copolymer (unimer) and rather compact supermolecular aggregates (micelles) with a relatively narrow molecular weight distribution. The unimer/micelles weight ratio and the weight of micelles were determined as a function of the composition of the mixed solvent, temperature, and copolymer concentration. Verdunnte Losungen des Dreiblockcopolymeren vom Typ Styrol-Butadien-Styrol weisen im selektiven Losungsmittelgemisch Tetrahydrofuran/Allylalkohol eine mehr oder weniger stark ausgepragte Trubung auf. Die Methoden der Sedimentationsgeschwindigkeit und Lichtstreuung zeigen, das diese Losungen zwei Komponenten enthalten: namlich molekular gelostes Copolymeres (Unimer) und ziemlich kompakte ubermolekulare Aggregate (Micellen) mit einer verhaltnismasig engen Molekulargewichtsverteilung. Das Gewichtsverhaltnis Unimer/Micellen und das Micellargewicht wurden in Abhangigkeit von der Zusammensetzung des Losungsmittelgemisches, der Temperatur und der Copolymerkonzentration ermittelt.

The effect of errors of the concentration (c-) and the light-scattering molar mass (M-) detector in gel permeation chromatography (GPC) on the accuracy of the determination of the molar mass distribution (MMD) was analyzed. Model calculations showed that the reliability of MMD obtained from c-detector data and from a carefully performed calibration dependence is higher than that obtained by combining data of the M- and c-detectors. A criterion of the uncertainty of the MMD determination by the GPC method with the M-detector was suggested, and its dependence on MMD parameters of the analyzed polymer and on the magnitude of injection was investigated.

The effect of errors of concentration and molar-mass detectors in GPC on the accuracy of determining molar-mass averages Mn and Mw was analyzed. Model calculations show that by means of GPC with an on-line low-angle laser light-scattering (LALLS) photometer only Mw can be determined with acceptable accuracy. Mn can be determined with acceptable accuracy only for polymers that have very small polydispersities. Mn can be determined with greater accuracy from data of a concentration detector and chromatographic-column-calibration data. The most suitable procedure for the determination of Mw seems to be a direct integration of the molar-mass detector output, even if the error due to neglecting the second virial coefficient term is significant. Compared with the inaccuracy of detectors, axial dispersion appears not to be the main source of errors in GPC with an on-line molar-mass detector.

Solubilization by micelles of a three-block copolymer poly(styrene-butadiene-styrene) with a polybutadiene core was studied by the light scattering method on three types of solubilizate: polybutadiene with (a) low and (b) high molar mass (with respect to the polybutadiene block of the copolymer), and (c) a block copolymer poly(styrene-butadiene-styrene) with a high content of butadiene. True solubilization of polybutadiene into the cores of spherical micelles occurs in case (a); in case (b) polybutadiene forms partially stabilized, emulsion-like large droplets. In case (c) stable mixed micelles are formed having either lower or higher molar mass with respect to that of the original micelles, depending on the ratio of molar masses and on the composition of both copolymers. A similarity between solubilization of hydrocarbons by micelles of soaps or surfactants in aqueous solutions and solubilization of polymers by copolymer micelles in selective solvents is pointed out.

The intensity of light scattered from dilute solutions of mixtures of two nonidentical polymers in a single solvent was measured. The parameter A24 characterising the thermo-dynamic interaction of two nonidentical polymer molecules in solution was calculated for several systems polymer 2 - polymer 4 - solvent. For chemically strongly different polymers, A24 is independent of molecular weights of the polymers and probably also of solvent. A24 is related to the compatibility of both polymers and decreases contrary to expectation with increasing chemical difference between polymers 2 and 4.

An attempt was made to prepare well-defined graft copolymers by the coupling reaction between acyl chloride groups located along the backbone chain and monohydroxy-terminated grafts prepared separately. The molecular weights and the parameters of heterogeneity in chemical composition of the products were determined by light scattering and osmometry. The determination of molecular characteristics revealed that the degree of grafting was low. The results therefore could not be confronted with a statistical model at this stage. The problems encountered in the synthesis, e.g., gel formation, and the data relating to the soluble products are discussed.

The technique of measurement of light scattering from dilute polyethylene (PE) solutions is reviewed. Conditions are discussed under which various PE samples can be characterized. The choice of the solvent affects the accuracy of molecular weight determination. It appears that measurement with thermodynamically poorer solvents yields results subjected to a smaller error. The interpretation of light scattering data is often disturbed by the presence of supermolecular structures in PE solutions. The effect of reprecipitation on the behavior of PE samples is described. The measurements were mostly performed on PE standards and on the Czechoslovak sample Liten Macro.

When methyl methacrylate is polymerized in aqueous medium in the presence of gelatin, graft copolymer macromolecules with gelatine backbones and poly(methyl methacrylate) (PMMA) grafts are formed. Due to the presence of graft copolymer, polymolecular micelles consisting of about 100 macromolecules are created. These micelles prevent macroscopic precipitation of PMMA. Fractionation in demixing solvents has been used to separate the components of the polymerization mixture, and the light-scattering method has been employed to determine their molecular weights. Each grafted macromolecule carries about one graft. The hypothesis of random grafting from gelatin backbones seems to explain most of the experimental observations.

The experimentally determined distribution of the chemical composition of styrene/butadiene block copolymers reported by Kuhn is compared with the results of a model calculation assuming that the constituent blocks have a gamma (Schulz-Zimm) distribution of molecular weights and the ratios of weight- to number-average molecular weights are Mw/Mn = 1,025 or Mw/Mn = 1,05. A good agreement is found between experimental and calculated distributions.

Association of a graft copolymer polyisoprene-graft-polystyrene in solvent mixtures selective either for polyisoprene backbone (THF/heptane) or for polystyrene grafts (THF/ethanol; 1,4-dioxane/ethanol) was studied by static and dynamic light scattering and sedimentation velocity. Values of molar mass and dimensions of graft copolymer micelles were determined, and qualitative information on the dynamics of the unimer ⇌ micelles equilibrium was obtained.

Samples of industrial high-density polyethylenes (Liten Macro, Liten FB 29, and Hostalen GM 9255 F) were divided into fractions by precipitation fractionation. The original samples and their fractions were characterized by light scattering, GPC, and viscometry. For all samples the molecular weight distribution is of logarithmic-normal type. High-density polyethylenes under investigation contain also high-molecular-weight fractions of pronouncedly branched structure, the content of branched molecules being, of course, considerably smaller than that in low-density polyethylenes.

The calculation of a general distribution function of chemical composition of random copolymers involving the instantaneous and conversion chemical heterogeneity is demonstrated. Typical examples offer a semiquantitative view about the effect of the two types of chemical heterogeneity on the shape and width of the distribution of chemical composition.

Determination pour du polyethylene (lineaire et ramifie), du polypropylene (atactique et isotactique), du polyisobutene et du polybutene-1 dans 2 solvants