کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7606735 | 1492964 | 2015 | 8 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Analytical pyrolysis in the determination of the aging of polyethylene
ترجمه فارسی عنوان
پیرولیز تحلیلی در تعیین پیری پلی اتیلن
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کلمات کلیدی
پیرولیز، پلی اتیلن، سالخورده، تخریب پلیمر، هیدرولیز و متیلاسیون کمک به حرارتی،
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
چکیده انگلیسی
Polyethylene is nowadays used in many applications with lifetimes of several decades. To predict the lifetime artificial aging is widely used, but only little is known of the chemical change of the polymer chains itself. We have used different types of unstabilized polyethylene and aged them in water at elevated temperature and a high pressure of oxygen to accelerate the natural aging processes and analyzed the materials by Py-GC-MS, infrared spectroscopy and size exclusion chromatography. With pyrolysis 2-oxoalkanes and 2-oxoalkenes as well as carboxylic acids were identified as the degradation products. Thermally assisted hydrolysis and methylation was successfully applied to assess the degree of oxidation, especially targeting the more polar compounds. With this technique alkane dioic acids have been identified as valuable marker compounds for the oxidative degradation of polyethylene. The mechanism of formation of fatty acids in thermally assisted hydrolysis and methylation has been elucidated using two different alkanones. With size exclusion chromatography it could be shown that the oxidation occurs randomly along the polymer chain and that the final degradation products are in the range of a few thousand g molâ1, irrespective of the original molar mass.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Analytical and Applied Pyrolysis - Volume 113, May 2015, Pages 315-322
Journal: Journal of Analytical and Applied Pyrolysis - Volume 113, May 2015, Pages 315-322
نویسندگان
Clemens Schwarzinger, Ingrid Hintersteiner, Bettina Schwarzinger, Wolfgang Buchberger, Bernhard Moser,