Thermal and kinetic characteristics in non-isothermal conditions of some aromatic copolyethers containing an octomethylenic spacer

• Authors: Mihaela Prajinaru , Natalia Hurduc , Silvia Alazaroaie , Otilia Catanescu , Nicolae Hurduc
• Languages of publication: EN

Abstracts

EN

The paper presents a study of the thermal properties of some aromatic polyethers obtained by phase trasfer catalysis technique. The polymes were synthesized starting from 1,8-dichloro-octane and various bisphenols: 4,4′-dihydroxyazobenzene, 4,4′-dihydroxydiphenyl, bisphenol A and 2,7-dihydroxynaphthalene. Molecular simulations were performed in order to obtain supplementary information concerning the chain conformation and inter-chain interactions. The presence of azobenzenic moieties induces high phase transition values, situated near the thermal stability limit. Therefore, the thermogravimetrical study of these polymers is very important for establishing the temperature limits for DSC and optical microscopy studies. All the polymers present a good thermal stability situated above the isotropization values. In these circumstances no special precautions are necessary for the characterization methods of the liquid crystalline behavior. The kinetic characteristics suggest a similar degradation mechanism by successive reactions. The inter-chain interactions do not influence the thermostability of the samples if the polar surface of the polymer is situated below a certain value.

Keywords

EN

Thermogravimetry; polyethers; azobenzene; liquid crystalline polymers

• Publisher: De Gruyter Open
• Journal: Open Chemistry
• Year: 2003
• Volume: 1
• Issue: 4
• Pages: 387-401

Dates

published

1 - 12 - 2003

online

1 - 12 - 2003

Contributors

author

Mihaela Prajinaru

• Department of Physical and Theoretical Chemistry, “Al. I. Cuza” University IASI, B-dul. Carol I No 11, 6600, IASI, Romania

author

Natalia Hurduc

• Department of Physical and Theoretical Chemistry, “Al. I. Cuza” University IASI, B-dul. Carol I No 11, 6600, IASI, Romania

author

Silvia Alazaroaie

• Department of Macromolecules, Technical University “Gh. Asachi” AISI, B-d Mangeron No 71, 700050, IASI, Romania

author

Otilia Catanescu

• Liquid Crystal Institute, Kent State University, 44242-0001, Kent, OH, USA

author

Nicolae Hurduc

• Department of Macromolecules, Technical University “Gh. Asachi” AISI, B-d Mangeron No 71, 700050, IASI, Romania

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Identifiers

DOI

10.2478/BF02475224