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Relationship between compatibility, internal stresses and stability in polymer composites III. Internal stresses revealed by pressure dependence of amorphous-crystalline coupling

✍ Scribed by Gh. Drăgan


Publisher
John Wiley and Sons
Year
1983
Tongue
English
Weight
737 KB
Volume
34
Category
Article
ISSN
0323-7648

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✦ Synopsis


A series of experimental data for crystallization and melting under pressure, obtained by using different measuring systems, are reconsidered on the basis of topoenergetic principles recently established. Two transformations statistically contribute a t least in the global processes in high density polyethylene and trans-1,4-polyisoprene samples, namely : (i) the lamellar segregation as a result of molecular fractionation and/or defect concentration, and (ii) the lamellar thickening. These processes show a transition in their nature and/or amplitude for a value of approximately 200 MPa for the externally applied pressure during crystallization or melting. This transition is explained by morphological changes in the amorphous-crystalline coupling.

Beziehungen zwischen Vertraglichkeit, inneren Spannungen und

Stabilitut in Polymerverbunden. I I I . Aus der Druckabhangigkeit der amorph-kristallinen Urnwandlungen errnittelte innere Spannungen Eine Rcihe nach verschiedenen MeRverfahren erhaltener experimenteller Daten zum Kristallisations-und Schmelzverhalten unter Druck wurden unter dem Gesichtspunkt von in neuerer Zeit entwickelten topoenergctischen Prinzipien neu interpretiert. Mindestens zwei Umwandlungsvorgange tragen statistisch zu den globalen Prozessen in Polyctliylen hoher Dichte und in trans-l,4-Polyisopren bei, nanilich (ij die lamellare Segregation als Folge der molekularen Fraktionierung und/odcr dcr Defektkonzentration und (ii) das lamellare Dickenwachstum. Diese Prozesse weiscn bei eineni BuBeren Druck von etwa 200 MPa eine Wandlung ihrer Natur und/oder L4niplitude auf. Diese Wandlung wird durch eine morphologische Anderung des amorph-kristallinen Zustandes erklart. B3auaocew3b aeircdy Coeaecmuaocmbio, enympennuau Hanpfcxenuwwu u CmabUAb%oCmbIO e nonuaepnb1.x ?coano-3umnbix aamepuawax. ZIacrnb I I I . Bttympelznue nanpxzcenuw, onpedefiennbce u3 3aeucu~ocrnu amop&no-Epucmaanu-'tecmx npeepazqenug om ilaowenus Ha OCHOBe TOIlO3HepreTHYeCKHX IIpHHqHIIOB P a C C M a T p H B a e T C R q e J I b l f i P R A 3KCIIePHMeHTaJIbHbIX AaHHbIX 0 I I p O q e C -C a X KpHCTaJIJIH3aqHH 21 IIJIaBJIeHMH IIOR AaBJIeHHeM, IIOJIyYeHHbIX I I p t i M e H e H H e M p a 3 H b I X MeTOROB H3MepeHMFI. no K p a f i H e f i M e p e A B a TpaHC@OpMaI(HOHHblX RBJleHtiFI CTaTHCTHYeCKH ClIOCO6CTBYH)T PJIO6aJIbHbIM I I p O q e C C a M B IIOJIH-MOJIeKyJIHpHOrO @paKIJHOHHpOBa€IHR M / M J I t i K O H q e H T p a q H t i Ae@eKTOB, M (11) JIaMeJIJIFIpHOe yTOJIweHEle. 3 T M np0-'IT0 MOHCHO OB'bRCHHTb MOp@OJIOrWIeCKPIM H3MeHeHIleM a M O p @ H O -K p ~C T a J I J I H Y e C K O ~O COCTOFIHMFI.


📜 SIMILAR VOLUMES


Relationship between compatibility, inte
✍ Gh. Drǎgan 📂 Article 📅 1980 🏛 John Wiley and Sons 🌐 English ⚖ 491 KB 👁 1 views

## Abstract Some of the main working principles in behavior characterization of polymer systems deduced in topoenergetic terms are applied for three thermally driven transformation processes specific to macromolecular systems, namely: thermal oxidation of amorphous phase in high and low density pol