Поступила в редакцию 31 марта 2017 г. 2017 г., после доработки -20 апреля 2017 г.В контроле процесса отверждения эпоксидной смолы марки ЭД-20 использовали мето-дику определения в ней свободного бисфенола А (БФА) с помощью ТСХ в сочетании с циф-ровой цветометрией (ЦЦМ). Для проявления хроматографических пятен БФА применяли две цветных реакции. По цветометрическим параметрам двух электронных изображений прояв-ленных пятен в цветовой модели RGB строили лепестковые диаграммы (ЛД), геометрические параметры которых (площадь, периметр, форма) зависят от природы и концентрации аналита. В исследованиях использовали отвердители аминного типа -полиэтиленполиамин (ПЭПА) и Этал-45М. Формальная кинетика превращений БФА в реакционной массе удовлетворительно подчиняется уравнению первого порядка. В ходе реакции отверждения смолы ЭД-20 отверди-телем ПЭПА при 100 о С период полупревращения БФА равен ~ 14 минутам, а при использова-нии Этал-45М при 50 о С он сокращается до ~ 6 минут. Контроль отверждения осуществляли также методом ИК-спектроскопии. Этот метод позволяет контролировать изменение содержа-ния в смоле эпоксидных групп по изменению оптической плотности характеристических полос (915 см -1 ), но недостаточно эффективен в контроле содержания групп -ОН фенольного типа. Данные, полученные методом ТСХ в тандеме с ЦЦМ, хорошо дополняют ИК-спектроскопиче-скую информацию, демонстрируют высокую специфичность методики по отношению к группам -OH фенольного типа, что позволяет контролировать содержание свободного БФА в образцах отвержденных эпоксидных смол.Ключевые слова: бисфенол А, тонкослойная хроматография (ТСХ), ИК-спектроскопия, циф-ровая цветометрия, эпоксидная смола.For citation: Analitika i kontrol' [Analytics and Control], 2017, vol. 21, no. 2, pp. 135-143 DOI: 10.15826/analitika.2017.21.2.004 Control of the epoxy resin curing process according to the free bisphenol A content by TLC University, 84, Voronezh, 394006, Russian Federation 2 Voronezh State University of Engineering Technology, pr. Revoliutsii, 19, Voronezh, 394036, Russian Federation *Corresponding author: Oleg B. Rudakov, Submitted 31 March 2017, received in revised form -20 April 2017A method of determination of free bisphenol A (BPA) by TLC in combination with digital colorimetry (DC) was used to control the curing process of ED-20 brand epoxy resin. For the development of BPA chromatographic stains, 2 color reactions were used. According to the colorimetric parameters of the 2 electronic images of the developed spots in the RGB color model, petal diagrams (PD) were constructed
The influence of latex formulations and a filler, Vulkasil, on the processing and physicochemical properties of urea3formaldehyde resins was studied.
An attempt has been made to obtain a working technological formula that regulates the addition of comonomer over time, which ensures the synthesis of a copolymer macromolecule with a constant composition and, accordingly, with predicted properties of both the copolymer and its modified porous composite materials. Mathematical modeling is based on the theory of the kinetics of copolymerization, which takes into account the reactivity of monomers by means of copolymerization constants of reacting comonomers. The starting base was the kinetics of the copolymerization of two comonomers, significantly differing in their reactivity, which required a sequential, stepwise supply of a less reactive monomer to the reaction medium with a more active monomer. This technological technique contributes to maintaining the constancy of the initial ratio of comonomers and, accordingly, the synthesis of a copolymer with a constant composition, structure and properties. The dependence of the sequence of supply of comonomer to the reaction medium required the introduction of a generalized effective binary copolymerization rate coefficient. To find the generalized coefficient of the copolymerization rate, the operation of logarithm was performed and the current expression of the dependence of the concentration change of the more active monomer in time in a linear form was translated. This mathematical technique made it possible to use software to process reference information to obtain the necessary coefficients for the working formula. As a result of mathematical modeling using the basic principles of binary copolymerization, the law of effective masses, and the least squares method, a working formula is obtained that allows one to regulate the given introduction of a less active monomer into the reaction medium in time. The model is analyzed using background information, the basic concepts of binary copolymerization and can be used in technological calculations when producing copolymers with specified characteristics in composition and structure.
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