Zur unverträglichkeit von polymergemischen. 2. Trübungsmessungen am system polystyrol/polymethylmethacrylat/benzol

The first visual points of turbidity were determined in the ternary system polystyrene/polymethylmethacrylate/benzene. Mathematical equations are given for the dependence of the turbidity points on molecular weight and concentration. It is possible to extrapolate these equations to solid polymers. If the molecular weight of one of the polymers is known, the compatibility in the solid state of the polymers can be calculated. Test measurements on films show, that the method of extrapolation is a valid approximation.     

聚合物合金相容性的预测和表征

介绍混合焓变原则和溶解度参数原则等预测聚合物合金相容性的方法,以及表征聚合物合金相容性的方法,如共同溶剂法、玻璃化转变温度法、稀溶液粘度法、显微镜法、红外光谱法、超声波技术和小角中子散射法等。指出多种表征方法的综合应用可使聚合物合金相容性的评价结果更加准确可靠。     

Novel colloidal nanofiber electrolytes from PVA‐organoclay/poly(MA‐alt‐MVE), and their NaOH and Ag‐carrying polymer complexes

Novel multifunctional polymer nanofiber electrolytes with covalence crosslinked structures from various solution blends of reactive intercalated poly(vinyl alcohol)/octadecylamine montmorillonite (as a matrix polymer), poly(maleic anhydride‐alt‐methyl vinyl ether) (as a partner polymer) and their NaOH‐absorbing and Ag‐carrying polymer complexes were fabricated via electrospinning. Chemical, physical, morphological, and electrical properties of nanofiber structures were investigated by FTIR, XRD, SEM, and electrical analysis methods. Ag precursors in fiber composites significantly improved phase separation processing, fiber morphologies, diameter distributions, and electrical properties of the fibers. In situ generation of Ag nanoparticles and their distribution on nanofiber surfaces during fiber formation occurred via complex formation between silver cations and electronegative functional groups from both matrix and partner polymers as stabilizing/reducing agents. Electrical resistance and conductivity strongly depended on matrix/partner polymer ratios and absorption time of NaOH solution on nanofibers. Addition of NaOH changed the electrical properties of fiber structures from almost dielectric state to excellent conductivity form. The fabricated unique nanofiber electrolytes are promising candidates for applications in power and fuel cell nanotechnology, electrochemical, and bioengineering processes as reactive semiconductive platforms. POLYM. ENG. SCI., 56:204–213, 2016. © 2015 Society of Plastics Engineers     

Zur phasentrennung von polymergemischen in lösung

Usually, mixtures of solutions of two different polymers in the same solvent are incompatible. This incompatibility leads to an intensive turbidity of the mixture and finally, to the formation of two phases. The turbidity disappears on dilution with the same solvent, because the polymers are compatible below a certain polymer concentration c_kr. In principle, the same effects occur also with mixtures of polymers in the solid state (polymer blends), but here the aggregation of the microphases is impossible due to the high viscosity. Up to now, there is little known about the composition of the two phases above c_kr. Therefore, we studied the distribution of two different polymersin solution regarding molecular weight and concentration into both phases. It was varied the polymer ratio, the molecular weight, the overall concentration and the nature of the solvent. Polystyrene and polyvinyl acetate were used as polymers because they can easily be separated from each other which is necessary when analysing the different phases; this analytical separation was carried out for each individual phase. The following results were obtained: Each phase contains both polymers; in addition there occurs a fractionation according to molecular weight during the phase separation for both polymers. The polymer distribution in the two phases regarding molecular weight, amount of polymer, and concentration depends not only upon initial concentration, molecular weight and weight ratio of the two polymers but also upon the different degree of solvation of the macromolecules in different solvents. When mixtures of solvents are used, an additional partially separation of the solvent into both layers takes place.     

Solution and solid‐state NMR investigation of poly(methyl methacrylate)/poly(vinyl pyrrolidone) blends

The development of polymer blends has become very important for the polymer industry because these blends have shown to be a successful and versatile alternative way to obtain a new polymer. In this study, binary blends formed by poly(methyl methacrylate) (PMMA) and poly(vinyl pyrrolidone) were prepared by solution casting and evaluated by solution and solid‐state NMR. Variations in the microstructure of PMMA were analyzed by ¹³C solution NMR. Solid‐state NMR promotes responses on physical interaction, homogeneity, and compatibility to use these blends to understand the behavior of the ternary blends. The NMR results led‐us to acquire information on the polymer blend microstructure and molecular dynamic behavior. From the NMR solution, it was possible to evaluate the microstructure of both polymer blend components; they were atactic. From the solid state, good compatibility between both polymer components was characterized. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 372–377, 2004     

Effect of the type of polymer functional groups on the structure of its film formed on the alumina surface – Suspension stability

The effects of polymer functional group and solution pH on stability of colloidal Al₂O₃ water suspension were studied. Both the nonionic polymers: polyethylene glycol (PEG), polyethylene oxide (PEO) and the ionic ones: polyacrylic acid (PAA), polyacrylamide (PAM), polyvinyl alcohol (PVA) were used in the experiments. The following methods were applied: turbidimetry (stability measurements), spectrophotometry (determination of polymer adsorption), viscosimetry (thickness of polymer adsorption layer), potentiometric titration (solid surface charge density) and microelectrophoresis (potential zeta). It was shown that anionic polyacrylic acid is both the most effective stabilizer (at pH 9) and flocculant (at pH 3) of the alumina suspension. Its carboxyl groups have the greatest affinity for the surface active sites (the largest adsorption) of all functional groups present in the other examined polymers. The latter, i.e. hydroxyl (PEG, PEO, and PVA) and acetate (PVA) show a much lower affinity for the Al₂O₃ surface (negligible adsorption) and minimally affect the stability of the alumina-solution system.     

Relation between the repulsion of incompatible and compatible polymers in solution and their degree of mixing in the solid state: the memory effect

The incompatible polymer pairs polystyrene (PS)/poly(methyl methacrylate) (PMMA) and polystyrene (PS)/poly(oxyethylene) (POE) and the compatible polymer pair POE/PMMA have been studied in solution and in the solid state. A close relation is observed between the behaviour in solution and in the solid state for both incompatible and compatible polymer mixtures. When we use a selective solvent and when the molecular masses of the polymers of the mixture are different, even compatible polymers behave like incompatible polymers; the obtained films present an important demixing. The opposite is observed when the films are obtained by casting from a common solvent and when the two polymers possess similar molecular masses. In this case, even incompatible polymers behave like compatible polymers. These results confirm the already reported memory effect when we go from the solution to the solid state. © 2000 Society of Chemical Industry     

聚烯烃接枝马来酸酐作为增容剂的应用

聚合物共混改性是制备新型高分子材料极为有交的方法，其中的关键是要解决各种聚合物之间一般相容性很差的问题，通常的解决办法是加入合适的增容剂，聚烯烃接枝马来酸酐（PO-g-MAH)是研究的很多的增容剂。制备聚烯烃接枝马来酸酐的方法有熔融法、溶液法、辐射法和固相法，其中最重要的方法是熔融法，笔者主要介绍了聚烯烃接枝马来酸酐作为增容剂在改性聚酰胺（PA6、PA66、PA12、PA1010）、聚酯（PET、PBT）、热塑性聚氨酯（TPU）等聚合物共混物，聚烯烃/无机填料，聚烯烃/有机纤维，复合增强材料，粘结剂等方面的应用，聚烯烃接枝马来酸酐与其它聚合物原位反应生成共聚物，一方面降低了表面张力，使得分散相在基体中分散得更好；另一方面增强了两相的粘合力，从而达到了增容的目的。     

Zur unverträglichkeit von polymergemischen IV. Lichtstreuungsmessungen an hochmolekularem poly-α-methylstyrol in polymethylmethacrylat/benzol

High molecular weight Poly-α-methylstyrene was investigated by means of light scattering in the isorefractive polymer/solvent mixture Polymethylmethacrylate/benzene. The dependence of the scattering on the concentrations could be interpreted theoretically in terms of the Stockmayer light scattering theory for multicomponent systems. It turns out that Poly-α-methylstyrene is essentially more compatible in Polymethylmethacrylate/benzene compared with polystyrene. This is valid not only in solution but also in the solid state. In agreement with this better compatibility the decrease in the radii of gyration of the poly-α-methylstyrene is less pronounced than that of the radii of the polystyrene if polymethylmethacrylate is added.     

Zur unverträglichkeit von polymergemischen. VII. Lichtstreuungsmessungen an quaternären und quintären polymer-systemen polymer(1)/polymer (2)/polymer(3)/benzol und polymer(1)/polymer(2)/polymer(3)/polymer (4)/benzol

A polystyrene of high molecular weight was investigated by means of light scattering in isoerefractive polymer/benzene mixtures. Two or three of the following polymers are used, which are isorefractive with benzene: polymethylmethacrylate (PMMA), polybutadienne (PB), and polyisobutene (PIB). It is possible to determine the degree of incompatibility of the ?unvisible”? polymers by a comparison of the ?-points of PS in the multi-component systems with the ?-points PS in the ternary systems PS/polymer(2)/benzene. In all cases it turned out, that the degree of compatibility of PS with the other polymers increased by a further addition of a chemical different polymer.     

Novel FTIR method for determining the crystallinity of poly(ε‐caprolactone)

By employing Fourier transform infrared spectroscopy (FTIR) and curve–fitting techniques, the degree of crystallinity of poly(ε‐caprolactone) (PCL) aged at room temperature for 1 month was estimated to be 49 ± 2 %. The degree of crystallinity determined by FTIR in this work is comparable with those found by other conventional techniques. It is suggested that the FTIR procedure established here for the crystallinity determination of PCL should also be suitable for the quantitative analysis of solid‐state morphology of polymers containing carbonyl or other functional groups. © 2000 Society of Chemical Industry     

Verträgliche Polymermischungen durch Säure-Base-Wechselwirkungen

Poly-2-ethyl hexylacrylate and the copolymer of 30% b. w. of styrene and 70% b. w. of hexyl methacrylate are incompatible per se. Modification of the polyacrylate by incorporating acrylic acid and of the styrene containing copolymer by incorporating aminogroups render those polymers compatible. all blends of interest show a cloud point on heating. Polymer compatibility increases as the content of acid and basic groups in the polymer increases. Substantial inequality in the acid base ratio will cause asymmetry in the phase diagram especially so when there are not too many interacting groups present.     

Self-coloured Polymers based on Anthraquinone Residues

The numerous studies of the formation of self-coloured polymers, based on anthraquinone residues, is summarized. In these polymers, the chromophoric groups are an integral part of the polymer. The possible structural types of these polymers are discussed in relation to the methods used to incorporate the anthraquinone-based chromophoric groups in the polymer chains. The possibility of using such polymers as self-coloured plastics or fibres is considered but this possibility is regarded as of lesser importance compared with the use of such polymers for other purposes, such as redox catalysts, and heat resistant pigments, plastics and fibres.     

A new resin system for super high solids coating

This paper concerns a super high solids coating composed of two polymers; a silicone polymer containing SiH groups, and an acrylic or polyether polymer containing C=C groups. The silicone polymer was prepared by the equilibrium reaction of SiH containing polysiloxane and other organosiloxanes in the presence of sulfuric acid. Acrylic polymers were obtained by free radical polymerization of a monomer having an alkenyl group and other vinyl monomers. Homogeneous clear paints were available by adjusting compatibility of polymers, and VOCs of the paints were very low due to the low viscosity of a silicone polymer and the absence of polar functional groups in the coating system. The crosslinking reaction of this coating occurred through the hydrosilylation reaction between SiH and C=C groups. The performances of cured films, such as etch resistance and durability, were excellent.     

NMR study of poly(vinylpyrrolidone)/poly(ethylene oxide) blends

Development of polymeric blends has become very important for polymer industries because they have been shown to be successful and versatile alternatives to obtain new polymers. In this work binary blends formed by poly(vinylpyrrolidone) (PVP) and poly(ethylene oxide) (PEO) were studied by solution and solid‐state NMR to determine their physical interaction, homogeneity, and compatibility for use as membranes to separate water/alcohol. The NMR results allowed us to acquire information on the microstructure and molecular dynamic behavior of polymer blends. From the NMR solution it was possible to evaluate the microstructure: PVP presented a preferential syndiotactic distribution sequence and PEO presented two regions, one crystalline and the other amorphous. Considering the solid‐state NMR results it was possible to evaluate the molecular dynamics and all binary blends, showing that PEO behaves as a plasticizer; some intermolecular interaction was also observed. An important point was to evaluate the microstructure of the carbonyl PVP using cross polarization/magic‐angle spinning (CP/MAS) and CP/MAS/dipolar decoupling that was not observed before. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2820–2823, 2002     

Functional water‐soluble polymers: polymer–metal ion removal and biocide properties

Water‐soluble polymers have attracted much interest due to their potential applications in environmental protection engineering to remove harmful pollutants and in biomedicine in the areas of tissue engineering, within‐body implants or other medical devices, artificial organ prostheses, ophthalmology, dentistry, bone repair, and so on. In this review, particular emphasis is given to the ability of water‐soluble polymers with amine, amide, carboxylic acid, hydroxyl and sulfonic acid functional groups to remove metal ions by means of the liquid‐phase polymer‐based retention (LPR) technique that combines the use of water‐soluble polymers and ultrafiltration membranes. The second part is dedicated to showing the potential application of functional water‐soluble polymers and their polymer–metal complexes as biocides for various bacteria. These polymers and polymer–metal complexes show an efficient bactericide activity, especially to Gram‐negative bacteria, Staphylococcus aureus reaching concentrations lower than 4 µg mL^?1. This activity depends on polymer size, type of metal ion, contact time and concentration of polymer and metal ion. The discussion reveals that in the case of the LPR process the efficiency of metal ion removal depends strongly on the type of polymer functional group and the feed pH value. In general, two mechanisms of ion entrapment are suggested: complex formation and electrostatic interaction. In the case of the medical use of water‐soluble polymers and their complexes with metal ions, the review documents the unique bactericide properties of the investigated species. The polymer‐metal ion complexes show a reduced genotoxic activity compared with free metal ions. Copyright © 2009 Society of Chemical Industry     

Synthesis and characterization of poly(allyl methacrylate) obtained by γ‐radiation

Allyl methacrylate was polymerized by γ‐radiation under vacuum in solution and atom transfer radical polymerization (ATRP) methods and also in the presence of atmospheric oxygen in bulk. The kinetic curve is S‐type with a longer induction period, because of the presence of oxygen, in bulk polymerization. The curve for the solution polymerization is almost linear with a short induction period. The rate started to decrease after about 60% conversion and reached to a limiting conversion of 100%. The polymerization by ARTP method using γ‐radiation as initiator instead of conventional heating method gave a kinetic curve of linear character up to about limiting conversion of 100%. The polymers obtained were mostly gel type with linear chain fractions at lower conversions. The polymer characterizations were carried out by FTIR, differential scanning calorimetry, NMR, TGA, and XRD methods. The polymers were shown to proceed by the opening of vinyl groups. The allyl groups caused a limiting crosslinking, but 98–99% of the allyl groups are shown by FTIR and NMR, unchanged during the polymerization. The cyclic type polymer formation was not likely taking place. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1076–1083, 2007     

Perspektiven der Säure‐Base‐Methode zur Untersuchung der Oberflächeneigenschaften von Polymeren

Modern methods for determining the surface free energy and their parameters were analyzed in the context of the presented investigations. The method of Berger and van Oss‐Chaudhury‐Good were found as the most suitable method for the determination of wetting solid polymer surfaces. Methods of nonlinear systems by Della Volpe and Siboni were evaluated and adapted. Various data of the surface free energy as well as its components have been identified for a number of polymer surfaces by application of spatial equation solutions.     

聚合物间相容性的预测和表征及在高分子合金分离膜中的应用

简要介绍了聚合物间相容性的预测及表征方法及在高分子合金分离膜中的应用。聚合物形成共混体系的相容性的预测能够通过聚合物间溶度参数或混合焓变来实现。可以用目视法或溶液粘度法方便地表征合金膜铸膜液内聚合物相容性，高分子合金致密膜中聚合物相容性则可以通过合金膜的光学透明度、显微镜观察等方法表征，也可以通过测量聚合物合金体系Tg的方法来测量。另外相容性也可以通过滤谱学方法加以辅助说明。以上预测和表征方法都与合金膜具体实例联系，表明这些方法在合金膜研究中有着广泛的应用。