کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5186092 1381095 2007 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Structure and dynamic mechanical properties of poly(ethylene terephthalate-co-4,4′-bibenzoate) fibers
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Structure and dynamic mechanical properties of poly(ethylene terephthalate-co-4,4′-bibenzoate) fibers
چکیده انگلیسی

Poly(ethylene terephthalate-co-4,4′-bibenzoate) (PETBB) fibers containing 5, 15, 35, 45, 55, and 65 mol% bibenzoate (BB) were melt spun. Fiber structure has been determined using wide angle X-ray diffraction, birefringence, and FTIR spectroscopy. When drawn to their respective maximum draw ratios, the structures and properties of high BB containing fibers (PETBB45, 55 and 65) are significantly different than those of PET and low BB containing fibers (PETBB5, 15, and 35). For example, 90% of the ethylene glycol units in high BB containing fibers are in the trans conformation, while only 80% of these units are in trans conformation in PET and low BB containing fibers. Overall orientation of the high BB containing fibers is higher (orientation factor f > 0.85) than those of PET and low BB containing fibers (f < 0.6). Orientation of the crystalline regions is quite high (fcr ∼ 0.95) for both groups of fibers, while orientation of the amorphous regions (fam) of high BB containing fibers is higher (∼0.8) than those of the PET and low BB containing fibers (∼0.4). High BB containing fibers exhibit much higher storage modulus and modulus retention with temperature than low BB containing fibers. Glass transition temperature determined from the dynamic loss tangent peak decreased with increasing BB content, while this transition completely disappeared in the high BB containing fibers. The magnitude of the secondary transition, observed at about −50 °C, decreased with increasing BB content. Another secondary transition, not observed in PET, was observed at about 70 °C in high BB containing fibers. These dynamic mechanical results have been rationalized in terms of the observed structural parameters.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 48, Issue 6, 8 March 2007, Pages 1651-1658
نویسندگان
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