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Date: 24-9-2017
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Date: 29-9-2017
593
Date: 25-2-2016
10904
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TRANSPOLYPENTAMER
Transpolypentamer (TPR) is produced by the ring cleavage of cyclopentene. Cyclopentene is obtained from cracked naphtha or gas oil, which contain small amounts of cyclopentene, cyclopentadiene, and dicyclopentadiene. Polymerization using organometallic catalysts produce a stereoregular product (trans 1,5-polypentamer):
Due to the presence of residual double bonds, the polymer could be crosslinked with regular agents. TPR is a linear polymer with a high trans configuration. It is highly amorphous at normal temperatures and has a Tg of about 90°C and a density of 0.85.
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"عادة ليلية" قد تكون المفتاح للوقاية من الخرف
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ممتص الصدمات: طريقة عمله وأهميته وأبرز علامات تلفه
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الأمين العام للعتبة العسكرية المقدسة يستقبل شيوخ ووجهاء عشيرة البو بدري في مدينة سامراء
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