摘要:

π-A isotherms of monolayers of various copolymers containing carboxyl groups derived from acrylic acid (AA) were measured. The conformation of polymer adsorbed on the water surface and interaction forces between polymer and water surface (considered to be a model for the surface of inorganic powders) owing to AA groups is discussed based on the π-A isotherms.

ISSN:0022-2348    

DOI:10.1080/00222348208204932

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

A radial distribution function for polystyrene has been obtained by electron diffraction and agrees well with published X-ray work. The changes in this radial distribution function have then been observed as the material suffered electron radiation. The main effect of radiation was the removal of any structure at distances greater than about 6 Å, and this was interpreted in terms of decrease in intramolecular order with radiation.

ISSN:0022-2348    

DOI:10.1080/00222348208204933

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The phase transformation from the tetragonal to the hexagonal crystal modification in highly oriented lamellae of poly-butene-1 has been followed by transmission electron microscopy (TEM). It is found that the reaction-controlling step is the nucleation process. No lattice orientation relationship (besides the [001]-direction, which is parallel in both crystal modifications) exists between non-transformed and transformed crystals. The nucleation is strongly enhanced by thermal or external stresses. Crystal growth, nucleated by external stresses, was observed at temperatures as low as — 150°C. The molecular mechanisms of the transformation are discussed.

ISSN:0022-2348    

DOI:10.1080/00222348208204934

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Standard analytical procedures for SAXS investigations of isotropic samples with globular or “spongelike” inclusions use Porod's asymptotic law and the Porod invariant. In this work another method of analysis is presented which gives directly the volume fraction of the inclusions and the specific inner surface of the sample. Previously these values could only be obtained by performing other measurements in addition to SAXS.

ISSN:0022-2348    

DOI:10.1080/00222348208204935

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Electron microscopy, x-ray diffraction, and melting data have been obtained on blends of nylon 6 and nylon 12 which have been crystallized from solutions in hexylene glycol, 1, 6-hexanediol, and 1, 3-butanediol. Experimental results suggest that individual crystals are formed with one or the other type of nylon, i.e., crystals containing both nylon 6 and nylon 12 chains do not form. Blend crystallization of the polyamides from solution under moderate crystallization conditions has effects on morphology, crystalline forms, and thickness of lamellar crystals. α-Form crystals of nylon 6 cause nylon 12 in blends to also crystallize in the a form during crystallization from hexylene glycol solution.

ISSN:0022-2348    

DOI:10.1080/00222348208204936

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Young's modulus, yield stress, tensile elongation at break, and tensile impact strength of filled polyethylene have been studied as a function of the content of two types of filler: Kaolin and calcium carbonate. Scanning electron microscopy proved that the kaolin particles are bonded to the polyethylene by means of polymer links, while similar links for calcium carbonate have not been detected.

ISSN:0022-2348    

DOI:10.1080/00222348208204937

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The attenuated total reflection (ATR) technique is shown to be promising in studying the molecular structure of polymer surfaces by IR spectroscopy. The problems connected with obtaining quantitative data from ATR spectra of films and fibers are considered. The influence of instrument errors on measurement accuracy is discussed in detail. Orientation of macromolecular chains, conformation structure, intensity of intermolecular interaction, average molecular weight, and other molecular characteristics obtained for surfaces and bulk of polymer films and fibers are presented.

ISSN:0022-2348    

DOI:10.1080/00222348208204938

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

The dependence of the dark electrical conductivity of poly [1, 2-acenaphthenediylidene-(3, 5, 6, 8-tetranitro-1, 2-acenaphthenediylidene)] films has been investigated as a function of their thickness, ranging between 150 and 900 nm, of the temperature (291–413 K) and the frequency (0.2–10 kHz) of the applied electric field. The thermal activation energy of the dc conductivity of the samples is found to be 0.8 eV in air and 0.7 eV in vacuum. The ac conductivity is 2 or 3 orders of magnitude higher than the dc conductivity. It increases nearly linearly with frequency and depends very slightly on temperature in the greater part of the temperature range under investigation. The experimental data are interpreted in favor of a hopping mechanism of conductivity.

ISSN:0022-2348    

DOI:10.1080/00222348208204939

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

A study has been made of the morphology and structure of nylon 6 crystals grown from stirred 1, 2, 6-hexanetriol solution. Nylon 6 crystallized as filmy aggregates around a stirrer and as suspended crystals in solution. Filmy aggregates are composed of fibrous crystals with diameters of 10–20 nm and the suspended crystals can be either elongated lamellae or needlelike. Electron microscopic investigations and x-ray diffraction measurements showed that the molecules in the fibrous crystals are folded and oriented perpendicular to the fiber axis. The fibrous crystals have the α-monoclinic crystal structure with the hydrogen bonds parallel to the fiber axis. The direction of the hydrogen bonds in the fibrous crystals is almost parallel to the flow direction of the solution. The suspended crystals are also α-form and chain-folded. The thermal behavior of the fibrous crystals was very similar to that of well-drawn nylon 6 fibers.

ISSN:0022-2348    

DOI:10.1080/00222348208204940

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Experimental results for concentrated solutions of nitrocellulose, cellulose triacetate, and cellulose acetate are presented, indicating that the points v2* of onset of anisotropy and v2A of attainment of full anisotropy are dependent on the magnitude and sign of χ12the polymer-solvent interaction parameter. The smaller is the polymer-solvent interaction parameter χ12the lower are the concentrations at the points v2* and v2A.

ISSN:0022-2348    

DOI:10.1080/00222348208204941

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor