Dynamic behaviour of nematic polymers in a magnetic field

• Autorzy: Filippov A. P.
• Języki publikacji: EN

Abstrakty

EN

Dynamic properties of some polymer nematics were investigated by Freedericksz transition methods in a magnetic field. The linear aromatic polyester, comblike combined side/chain-main/chain polymer and comblike copolymers with mesogenic and functional acid groups in side chains were studied. The temperature dependences of the effective rotation viscosity γ₁* were obtained. At close molecular weight and temperature the γ₁* value for linear polymer exceeds that for comblike combined polymer. Therefore, the existence of side mesogenic groups decreases the velocity of the orientational processes of polymer nematic. However, the highest values of effective rotation viscosity were obtained for the nematic phase of the comblike functionalized copolymers. Hence, the formation of hydrogen bonds in these copolymer leads to slowing of orientational processes. Influence of the intermolecular hydrogen bonds on dynamic properties of functionalized copolymers is stronger than that of intramolecular hydrogen bonds.

Słowa kluczowe

EN

polymer nematic; Freedericksz transitions; effective rotation viscosity; inter- and intramolecular hydrogen bonds

• Wydawca: Stowarzyszenie Elektryków Polskich ; Polska Akademia Nauk ; Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego
• Czasopismo: Opto-Electronics Review
• Rocznik: 2002
• Tom: Vol. 10, No. 1
• Strony: 63--68
• Opis fizyczny: Bibliogr. 17 poz.

Twórcy

autor

Filippov A. P.

• Institute of Macromolecular Compounds of Russian Academy of Sciences, 31 Bolshoi Pr., 199004 St. Petersburg, Russia,

Bibliografia

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