کد مقاله کد نشریه سال انتشار مقاله انگلیسی ترجمه فارسی نسخه تمام متن
5195962 1381362 1998 8 صفحه PDF سفارش دهید دانلود کنید
عنوان انگلیسی مقاله ISI
P-V-T relations in a series of longitudinal polymer liquid crystals with varying mesogen concentration
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
P-V-T relations in a series of longitudinal polymer liquid crystals with varying mesogen concentration
چکیده انگلیسی
Pressure-volume-temperature (P-V-T) relationships were determined for polymer liquid crystal (PLC) solids and melts up to 400°C and 240 J cm−3. We have studied a series of longitudinal PLC copolymers with the formula PET/xPHB, where PET = poly(ethylene terephthalate), PHB = p-hydroxyben-zoic acid (the LC component), with the mole fractions of the LC component 0 ≥ x > 0.8. The P-V-T results are represented by the Hartmann equation of state and its characteristic parameters ν∗, T∗and P∗ evaluated. In both solid and liquid phases the ν∗(x) and T∗(x) curves show minima near the concentration θLC limit above which islands of the LC-rich phase are formed. Surface tensions of melts are calculated as a function of x from the P-V-T data for the liquid state using the theory of Prigogine and Patterson. Increasing x first causes lowering of the cohesion of the single-phase structure dominated by the flexible PET. Above θLC limit the islands appear to impart their orientation to both phases; this is the channeling effect predicted earlier from the Flory statistical-mechanical theory of PLCs (Blonski et al., Macromolecules, 1993, 26, 84)
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 39, Issue 17, August 1998, Pages 4081-4088
نویسندگان
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