Observation of Phase Transition of Liquid Crystalline Polymers by Ultrasonic Method. (Hydroxypropyl)cellulose and (n-Hexanoyloxypropyl)cellulose
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چکیده
منابع مشابه
Ultrasonic measurements of the elastic moduli of liquid crystalline polymers
The five independent elastic moduli of extruded rods of two thermotropic liquid crystalline polymers, Vectra B900 and Vectra A950, and the nine independent moduli of an injection-moulded bar of Vectra A950 have been measured by ultrasonic methods at 10 MHz. For Vectra B900, the sharp rise in the axial extensional modulus C33 and the moderate drop in the transverse modulus C 11 with increasing d...
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Crystalline polymers build up complex structural entities, which blend amorphous and crystalline domains at a very small scale (≈ 10 nm). The coexistence of domains, which are of molecular, dimensions stems from the fact that the chains tend to fold upon crystallisation: this chain folding is a characteristic feature of polymers, and creates an organisational scale which is unique to polymers. ...
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ژورنال
عنوان ژورنال: Polymer Journal
سال: 1994
ISSN: 0032-3896,1349-0540
DOI: 10.1295/polymj.26.599