摘要:

AbstractMeasurements of the thermally stimulated discharge (TSD) current were carried out for isotactic plypropylene samples with different crystalline structures modified by annealing the samples in the temperature range from 120°C to 150°C. The analysis of TSD current maxima at 90°C and about 130°C revealed that they are attributed to the thermal release of free charge carriers from energetic traps. The investigations of the TSD current maximum at 90°C in the annealed i‐PP samples revealed a connection of the traps with the crystallite sizes and the existence of the disordered phase inside the lamellae between crysta

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380501

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe crystallinity of TCNQ complex salts of polycations containing S+atoms and different methylene group segments (Ks[x,y]) or/and aromatic groups (Ks[x, Ar]) in the main chain was investigated. Because the details of crystalline structure of these salts are not known, the total scattering power was taken as a characteristic of crystalline structure perfection of each complex salts. It is shown that the total scattering power depends on the content of the neutral TCNQ molecules in some Ks[x,y] complex salts as well as on the recrystallization conditions of Ks[x, Ar] complexes.

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380502

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractHindering and final blocking of the normal melt crystallization in central ethylene oxide (EO) blocks by methyl methacrylate (MMA) end blocks of increasing lengths in ABA type triblock copolymers synthesized anionically in a new way are investigated by differential scanning calorimetry and X‐ray scattering. Experimental studies of glass transitions, low temperature nucleation, and the morphologic ten‐nanometer structure are included. Low percentage amounts of long homo‐PEO chains can crystallize in an ABA matrix which otherwise is not normally crystallizable. It is concluded from the experiments that in our systems with PEO molecular masses up to 50 000 g/mol the motion of the chain ends is necessary for melt crystallization under normal condi

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380503

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe previously obtained results on sulphate‐water interactions both in liquid and solid states in the four measuring systems (high resolution mixing calorimetry, differntial scanning calorimetry, thermomechanical analysis, and dynamic thermal densimetric analysis) are retrieved according to the universal topoenergetic procedure by considering the solute concentration as governing potential. Ontogenic and phylogenic parameters defining the nature, the overall amplitude, the mass of the kinetic entity and the coupling strength of these interactions, allow to establish the composite structure both of pure water and of aqueous solutions. At least two structures exist in these specimens made from the pure water with isolated molecules and polymerized water molecules involving cations which catalyze H‐bond forming in polymeric cha

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380504

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractAus den in den vorangehenden Mitteilungen dargestellten Experimentalergebnissen werden verallgemeinerungsfähige Schlußfolgerungen zur Anwendbarkeit von Kryomethoden für die elektronenmikroskopische Präparation und zum Mechanismus der Sol‐Gel‐Umwandlung bei Polymeren gezogen. Als entscheidender Vorteil der Gefrierätztechnik ist die Möglichkeit kinetischer in‐situ‐Unterscuhungen zur Sol‐Gel‐Umwandlung anzusehen. Der Verlauf des Sol‐Gel‐Übergans wird für die hier untersuchten Beispiele der Gelbildung durch Phaseninversion (Phasentrennung), der ionotropen Gelbildung und der Bildung von Symplex‐Gelen als gekoppelter Diffusions‐Reaktions‐Mechanismus betrachtet, bei dem thermodynamische und kinetische Faktoren zu berücksichtigen sind, um beispielsweise die asymmetrische morphologische Struktur der Gele zu klären. Für des Anfangsstadium der Gelbildung werden spontan ablaufende „Phasentrennungsprozesse”︁ sowie morphologische Instabilitäten der fortschreitenden „Koagulationsfront”︁ als maßgebend angesehen. Auf gewisse Analogien zur Ausbi

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380505

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractAnhand phänomenologischer Befunde werden sog. Deformationssysteme definiert, die eine Systematisierung der thermisch stimulierten Rückstellung eingefrorener Deformationen ermöglichen. Eine Methode zur Bestimmung der Nachgiebigkeits‐ und der Rückstellfunktion wird skiz

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380506

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe influence of chlorinated polyethylene (CPE) and of the screw speed on the extrusion characteristics of unplasticized PVC blends, with and without addition of clay as a filling material, was investigated. For the blends with no filling material the curves of variation of the main extrusion characteristics (except the flow rate of the extruded material) exhibit shapes characteristic to polymer blends. The introduction of 10 parts of clay per 100 parts of PVC leads to a change of the curves, which exhibit a minimum for 7.0 parts CPE in the system. For this CPE content the values of the extrusion characteristics of the blends containing 10 parts clay approach very well those of the compounds without filling material.

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380507

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe effect of the molar ratio phenol: formaldehyde on the viscosity and the solid content of the resin has been investigated. The conditions for preparation of a resole with high solid content and low viscosity are studied

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380508

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractDie Additionspolymerisation von Bisphenol‐A‐diglycidylether (DGEBA) an aromatische, araliphatische, cycloaliphatische und hydroxysubstituierte aliphatische primäre Monoamine führt in der Schmelze bei 20 bis 130°C zu linearen Poly(aminodiolen) mit Molekülmassen M̄n= 10000 bis 20000 g. mol−1. Die Struktur der Additionspolymere wird durch1H‐ und13C‐NMR‐ und IR‐Spektroskopie, C,H,N‐Analysen und durch polymeranaloge Acetylierung der Hy

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380509

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY

摘要:

AbstractThe antielectrostatic properties of quaternary imidazolium chlorides deposited on low density polyethylene films were studied. The experiments point out that these chlorides possess certain antielectrostatic properties since they diminish the surface resistance by about two orders of magnitude, and the half decay time achieves values below 100 s. The antielectrostatic effect depends on the length of the radical in the positions one and three.

ISSN:0323-7648    

DOI:10.1002/actp.1987.010380510

出版商:Akademie Verlag GmbH    

年代:1987

数据来源: WILEY