| Yazarlar (3) |
Prof. Dr. Zekeriya YERLİKAYA
Kastamonu Üniversitesi, Türkiye |
Serpil Aksoy
Gazi Üniversitesi, Türkiye |
|
Erdal Bayramli
Middle East Technical University (Metu), Türkiye |
| Özet |
| A series of fully aromatic copolyesters based on p-acetoxybenzoic acid (p-ABA), hydroquinone diacetate (HQDA), terephthalic acid (TPA), and m-acetoxybenzoic acid (m-ABA) were prepared by a modified melt-polycondensation reaction. The copolyesters were prepared in two series in which series I is based on a two monomer system (p-ABA/m-ABA) and series II is based on a three monomer system (HQDA/TPA/m-ABA). The effect of different linear structures and kink moiety on the properties of the copolyesters were investigated systematically. The copolyesters were characterized by differential scanning calorimetry, thermogravimetric analysis, 1H-NMR, polarized optical microscopy, X-ray diffraction, and intrinsic viscosity measurements. It was found that the copolyesters exhibited nematic liquid-crystalline phases when the content of linear (p-ABA or HQDA/TPA) units was over 67 mol %. The melting or flow-transition temperatures were decreased with an increase of the content of kink m-ABA units. The copolyesters that contained p-ABA as linear units had a significantly higher degree of crystallinity compared to the copolyesters that contain HQDA/TPA as the linear units, implying a higher blockiness in the polymer chains as a result of the higher reactivity of the p-ABA units in the p-ABA/m-ABA system. All the copolyesters had poor solubility except the copolyesters containing at least 40 mol % of m-ABA, which were soluble in a dichloromethane/trifloroacetic acid (70:30 v/v) mixture. © 2003 Wiley Periodicals, Inc. |
| Anahtar Kelimeler |
| Liquid-crystalline polymer | Polycondensation | Structure | Thermal properties | X-ray |
| Makale Türü | Özgün Makale |
| Makale Alt Türü | SSCI, AHCI, SCI, SCI-Exp dergilerinde yayınlanan tam makale |
| Dergi Adı | JOURNAL OF APPLIED POLYMER SCIENCE |
| Dergi ISSN | 0021-8995 Wos Dergi Scopus Dergi |
| Dergi Tarandığı Indeksler | SCI |
| Makale Dili | İngilizce |
| Basım Tarihi | 12-2003 |
| Cilt No | 90 |
| Sayı | 12 |
| Sayfalar | 3260 / 3269 |
| Doi Numarası | 10.1002/app.12985 |
| Makale Linki | http://doi.wiley.com/10.1002/app.12985 |
| Atıf Sayıları | |
| WoS | 10 |
| SCOPUS | 9 |
| Google Scholar | 15 |
