کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5191093 1381225 2005 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Thin crystal melting produces the low-temperature endotherm in ethylene/methacrylic acid ionomers
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
Thin crystal melting produces the low-temperature endotherm in ethylene/methacrylic acid ionomers
چکیده انگلیسی
Upon extended aging at room temperature, ethylene/methacrylic acid (E/MAA) ionomers develop an endotherm near 50 °C in their differential scanning calorimetry traces. The origin of this low-temperature endotherm has been the subject of considerable debate, in part because direct structural probes have been little applied to its study. Here, we use in situ small-angle X-ray scattering and wide-angle X-ray diffraction to show that this endotherm reflects the melting of thin polyethylene crystals, which gradually develop following primary crystallization. These secondary crystals form within the amorphous layers separating primary crystals. When the framework of primary crystals is oriented by crystallization during flow, the secondary crystals follow this orientation, indicating that the secondary crystals are not isometric fringed micelles but instead have a substantial lateral extent.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Polymer - Volume 46, Issue 14, 27 June 2005, Pages 5118-5124
نویسندگان
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