DRY MIXTURES

661.728.892 – 537.635

[:ru]Арасланкин С. В.[:en]Araslankin, S. V.[:] [:ru]преподаватель кафедры физической химии, национальный исследовательский Мордовский государственный университет, Саранск, Россия / Ген. директор ООО «Экспонента», Саранск, Россия[:en]Lecturer of Department of Physical Chemistry National Research Mordovia State University, Saransk, Russia / CEO Exponenta LLC, Saransk, Russia[:]

[:ru]Кострюков С. Г.[:en]Kostryukov, S. G.[:] [:ru]к. х. н., доцент кафедры органической химии, национальный исследовательский Мордовский государственный университет, Саранск, Россия[:en]Ph.D. in Chemistry, Assoc. Prof. of Department of Organic Chemistry National Research Mordovia State University, Saransk, Russia[:]

[:ru]Петров П. С.[:en]Petrov, P.[:] [:ru]к.х.н., заведующий лабораторией ядерного магнитного резонанса Национальный исследовательский Мордовский государственный университет, Саранск, Россия ООО «Экспонента», Саранск, Россия[:en]Ph.D. in Chemistry, Head of NMR Laboratory National Research Mordovia State University, Saransk, Russia Exponenta LLC, Saransk, Russia[:]

Alitinform №2-3 (47) 2017 г. 68-81 p.

Abstract

The work is devoted to determining the substitution parameters of some commercial cellulose ethers by solid-state ¹³C NMR spectroscopy. The substitution parameters are the degree of substitution (DS) and molar substitution (MS). The objects of study are commercial additives based on hydroxyethyl cellulose (HEC), hydroxypropyl methyl cellulose (HPMC) and hydroxyethyl methyl cellulose (HEMC). In this paper, the degree of substitution (DS) and molar substitution (MS) were determined, and the distribution of the substituents at positions C-2, C-3 and C-6 of the glucopyranose ring were established. The calculation of the degree of substitution (DS) and molar substitution (MS) is based on an analysis of relative intensity values of the spectral regions in the solid-state NMR spectra of cellulose ethers and microcrystalline cellulose. Thus the degree of substitution and molar substitution were determined: MS_HEC = 1.41 and DS_HEC = 1.08; MS_HPMC = 0.69 and DS_HPMC = 1.78; MS_HEMC = 0.74 and DS_HEMC = 2.19. The results obtained are in conformity with the literature data. The proposed method differs from other existing methods in that it is a simple and informative.

Key words:

cellulose ethers, degree of substitution, molar substitution, solid-state ¹³C NMR spectroscopy, dry mixes