کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5190924 | 1381220 | 2005 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Colorless polyimides from 2,3,3â²,4â²-biphenyltetracarboxylic dianhydride (α-BPDA) and various aromatic bis(ether amine)s bearing pendent trifluoromethyl groups
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موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آلی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
A series of organosoluble and light-colored polyimides (III) was prepared from 2,3,3â²,4â²-biphenyltetracarboxylic dianhydride (α-BPDA) with various fluorinated aromatic bis(ether amine)s via two-step method with thermal or chemical imidization of poly(amic acid)s yielded polyimides. The III series had inherent viscosity of 0.74-1.01 dl/g and showed excellent solubility in a variety of organic solvents. They were soluble in the amide polar solvent, ether-type solvent, and chlorinated solvent. These polyimide films also showed a high optical transparency and less color intensity, with an ultraviolet-visible absorption edge of 369-382 nm and low b* values (a yellowness index) of 5.0-11.7. Glass-transition temperature of the III series was recorded at 244-319 °C and higher than the isomeric polyimides V series. Compared with the nonfluorinated polyimides IV, the III series showed lighter-colored and lower dielectric constants and moisture absorptions. The good tensile properties and excellent thermal properties of the III series were also observed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 46, Issue 15, 11 July 2005, Pages 5797-5807
Journal: Polymer - Volume 46, Issue 15, 11 July 2005, Pages 5797-5807
نویسندگان
Chin-Ping Yang, Yu-Yang Su,