Multifunctional Cyclic Carbonates Comprising Hyperbranched Polyacetals: Synthesis and Applications to Polymer Electrolytes and Networked Polymer Materials

Introduction. Application of renewable raw materials for manufacturing non-toxic components of polymer materials is of great practical interest. Cyclic carbonates on the base of epoxidated rubber tree oil could be seen as a promising alternative of fossil fuels. The ability of compounds containing cyclic carbonates to interact with primary amines and to form urethane and hydroxyl groups makes them rather efficient modifiers of amine-toughened epoxy compounds on the base of low-molecular diane oligomers. Introduction of cyclic carbonates enhances impact behavior of epoxy materials as well as their adhesion and strength properties. Materials and methods. Epoxy resin ED-20 was used for the research, as a cross-linking agent for cold toughening aminealkylphenol AF-2 was used; cyclic carbonates of epoxidated soy oils and rubber tree oil were applied as modifiers. Adhesional strength of bond joints has been determined in compliance with the GOST 28840-90, abrasive hardness of epoxy compound samples has been tested by the vertical optical caliper IZV-1. Results. When applying two-stage technology for obtaining epoxy cyclic carbonate compounds, there has been appeared a significant increase of adhesion to aluminum. This effect could be even more noticeable with increasing temperature during the stage of mixture of the amine toughener with the cyclic carbonate modifier. High viscosity of cyclic carbonate modifiers complicates the process of mixing components of the epoxy compound and correspondingly its application as a backing of glues and linings. The authors researched cyclic carbonates of epoxidated soy oil with various averaged functionality as modifiers. Application of epoxy materials CESO-75 as a modifier has proven to be more forward-thinking for the reasons of cost-efficiency and for operating and technological properties. CESO lowers the coefficient of static friction for epoxy materials together with enhancing their abrasion hardness. Conclusions. Cyclic carbonates of epoxidated plant oils (soy oil and rubber tree oil) as rather efficient non-toxic modifiers of epoxy polymers are of practical interest. They are produced on the base of annually renewable plant raw materials. Their application enables to enhance abrasion hardness and adhesion properties of epoxy compounds and also improve their antifriction properties.

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Polymer Ionics

MRS Bulletin ◽

10.1557/s0883769400061728 ◽

1989 ◽

Vol 14 (9) ◽

pp. 39-51 ◽

Cited By ~ 27

Author(s):

Mark A. Ratner ◽

D.F. Shriver

Keyword(s):

Polymer Electrolytes ◽

Materials Science ◽

Electrical Response ◽

Polymeric Materials ◽

Polymer Materials ◽

Solid Polymer ◽

Electronic Charge ◽

Charge Motion ◽

Substantial Progress ◽

Electrical Conductors

The preparation, utilization, and understanding of high polymers represents one of the great triumphs of chemistry and materials science in the 20th century. Synthetic polymers have traditionally been used as structural materials and electrical insulators. Biopolymers often exhibit interesting electrical response phenomena. A recent article in the MRS BULLETIN, for example, discussed piezoelectric properties of both synthetic and biopolymer systems. The newer, synthetic electroactive polymeric materials, however, represent one of the most exciting current areas of polymer materials science.Many synthetic ionic polymer materials are known; perhaps the first were the polyelectrolytes and crosslinked ion exchange materials. These are materials whose backbone contains charges of one sign, balanced by small counter ions of the opposite sign. Such polyelectrolytes have found very important applications in analytical chemistry, water purification, and chemical processing.Complexes, in which salts are dissolved in neutral polymer hosts, have until recently received less attention. The area of polymer/salt complexes became extremely active following the work of P.V. Wright, who first clearly showed that polyethylene oxide (PEO) is an excellent polymer host for a number of salts, and that the resulting solid polymer/salt complexes are electrical conductors. M. Armand broadened the investigation of electrical properties of polymer/salt complexes and pointed out that these materials might be useful in electrochemical devices, especially batteries.This article will discuss the formation, properties, behavior, and applications of polymer electrolytes and mixed conductors—that is, polymeric materials in which charge is transported either by ions or by ionic and electronic charge motion. Our concentration will be on solvent-free materials—materials in which no small molecule solvents are present. There is substantial interest, and substantial progress, in the area of solvent-swollen polymer electrolytes.

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Electron-diffraction studies in synthetic polymer materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075579 ◽

1983 ◽

Vol 41 ◽

pp. 362-365

Author(s):

D.T. Grubb

Keyword(s):

Electron Diffraction ◽

Synthetic Polymer ◽

Polymer Materials ◽

Crystallographic Structure ◽

High Dose ◽

Electron Dose ◽

Dose Rates ◽

First Case ◽

Diffraction Patterns ◽

The Many

Diffraction studies in polymeric and other beam sensitive materials may bring to mind the many experiments where diffracted intensity has been used as a measure of the electron dose required to destroy fine structure in the TEM. But this paper is concerned with a range of cases where the diffraction pattern itself contains the important information.In the first case, electron diffraction from paraffins, degraded polyethylene and polyethylene single crystals, all the samples are highly ordered, and their crystallographic structure is well known. The diffraction patterns fade on irradiation and may also change considerably in a-spacing, increasing the unit cell volume on irradiation. The effect is large and continuous far C94H190 paraffin and for PE, while for shorter chains to C 28H58 the change is less, levelling off at high dose, Fig.l. It is also found that the change in a-spacing increases at higher dose rates and at higher irradiation temperatures.

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Structure-property relationships of PE/PP sandwiched films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126998 ◽

1987 ◽

Vol 45 ◽

pp. 454-455

Author(s):

J. Petermann ◽

G. Broza ◽

U. Rieck ◽

A. Jaballah ◽

A. Kawaguchi

Keyword(s):

Mechanical Tests ◽

Polymer Materials ◽

Ionic Crystals ◽

Structure Property ◽

Polymer Systems ◽

Structure Property Relationships ◽

Oriented Films ◽

Materials Used ◽

Polymer Laminates ◽

Heated Glass

Oriented overgrowth of polymer materials onto ionic crystals is well known and recently it was demonstrated that this epitaxial crystallisation can also occur in polymer/polymer systems, under certain conditions. The morphologies and the resulting physical properties of such systems will be presented, especially the influence of epitaxial interfaces on the adhesion of polymer laminates and the mechanical properties of epitaxially crystallized sandwiched layers.Materials used were polyethylene, PE, Lupolen 6021 DX (HDPE) and 1810 D (LDPE) from BASF AG; polypropylene, PP, (PPN) provided by Höchst AG and polybutene-1, PB-1, Vestolen BT from Chemische Werke Hüls. Thin oriented films were prepared according to the method of Petermann and Gohil, by winding up two different polymer films from two separately heated glass-plates simultaneously with the help of a motor driven cylinder. One double layer was used for TEM investigations, while about 1000 sandwiched layers were taken for mechanical tests.

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Electron spectroscopic imaging (ESI) on multiphase polymer materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153713 ◽

1989 ◽

Vol 47 ◽

pp. 348-349

Author(s):

H.-J. Cantow ◽

M. Kunz ◽

M. Möller

Keyword(s):

Energy Loss ◽

Melt Spinning ◽

Chromatic Aberration ◽

Element Distribution ◽

Polymer Materials ◽

Specific Energy Loss ◽

Transmission Electron ◽

Multicomponent Polymer ◽

Diffraction Patterns ◽

Image Planes

In transmission electron microscopy the natural contrast of polymers is very low. Thus the contrast has to be enhanced by staining with heavy metals. The resolution is limited by the size of the staining particles and by the fact that electrons with different energy are focused in different image planes due to the chromatic aberration of the magnetic lenses. The integration of an electron energy loss spectrometer into the optical coloumn of a transmission electron microscope offers the possibility to use monoenergetic electrons and to select electrons with a certain energy for imaging. Thus contrast and resolution are enhanced. By imaging only electrons with an element specific energy loss the element distribution in the sample can be obtained. In addition, elastic bright field images and diffraction patterns yield excellent resolution. Some applications of the method on multicomponent polymer materials are discussed.Bulk polymer samples were prepared by ultramicrotoming at room temperature or well below the glass transition temperature. Very thin films for the direct observation of the structure in semicrystalline polymers were obtained by melt-spinning. Specimens were examined with a ZEISS CEM 902 operated at 80 kV.

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Quantitative high-resolution electron microscopy (HREM) of defects in ordered polymers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163290 ◽

1996 ◽

Vol 54 ◽

pp. 166-167

Author(s):

Patricia M. Wilson ◽

David C. Martin

Keyword(s):

Electron Microscopy ◽

Electron Beam ◽

High Resolution ◽

Liquid Crystalline ◽

High Resolution Electron Microscopy ◽

Polymer Materials ◽

Scattered Electron ◽

Crystalline Polymers ◽

Resolution Electron ◽

Beam Damage

Efforts in our laboratory and elsewhere have established the utility of low dose high resolution electron microscopy (HREM) for imaging the microstructure of crystalline and liquid crystalline polymers. In a number of polymer systems, direct imaging of the lattice spacings by HREM has provided information about the size, shape, and relative orientation of ordered domains in these materials. However, because of the extent of disorder typical in many polymer microstructures, and because of the sensitivity of most polymer materials to electron beam damage, there have been few studies where the contrast observed in HREM images has been analyzed in a quantitative fashion.Here, we discuss two instances where quantitative information about HREM images has been used to provide new insight about the organization of crystalline polymers in the solid-state. In the first, we study the distortion of the polymer lattice planes near the core of an edge dislocation and compare these results to theories of dislocations in anisotropic and liquid crystalline solids. In the second, we investigate the variations in HREM contrast near the edge of wedge-shaped samples. The polymer used in this study was the diacetylene DCHD, which is stable to electron beam damage (Jc = 20 C/cm2) and highly crystalline. The instrument used in this work was a JEOL 4000 EX HRTEM with a beam blanidng device. More recently, the 4000 EX has been installed with instrumentation for dynamically recording scattered electron beam currents.

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