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Определение гидроксильного числа полиэтиленгликолей методом дифференциальной сканирующей калориметрии


Е. В. Темникова, М. Н. Хасанов, А. С. Биктимерова; № 9 (83), 09.2017

Аннотация:

Разработана методика определения гидроксильного числа (ГЧ) бифункциональных простых полиэфиров (полиэтиленгликолей) в диапазоне от 28 до 380 мг KOH/г по температуре плавления Tпл, определяемой методом дифференциальной сканирующей калориметрии (ДСК). При условии постоянства функциональности полиэфира (f = 2) Tпл линейно зависит от ГЧ полиэфира. Методика апробирована при анализе промышленных образцов полиэтиленгликолей.

 

Ключевые слова: полиэтиленгликоль; гидроксильное число; дифференциальная сканирующая калориметрия; температура плавления; молекулярная масса.

Determination of Hydroxyl Number of Polyethylene Glycols (PEG) by Differential Scanning Calorimetry

E. V. Temnikova, M. N. Khasanov, and A. S. Biktimerova

A method for determination of hydroxyl number (HN) of bifunctional polyethers (polyethylene glycols) in the range from 28 to 380 mg KOH/g by melting point Tmelt using differential-scanning calorimetry (DSC) is developed. Provided that the functionality of the polyester is constant (f = 2), Tmelt exhibits a linear dependence on the hydroxyl number of polyester. The method was tested in the analysis of industrial PEG samples.

Keywords: polyethylene glycol; hydroxyl number; differential scanning calorimetry; melting point; molecular weight.

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