Komakha V. Commodity science estimation of acrylic water-dispersion paints with modified chalk

The dissertation is devoted to commodity science estimation of acrylic water-dispersion paints and coatings. It was proposed to use sedimentary chalk modificated by aqueous solution of potassium methylsiliconate and solution of a sodium salt of an acrylic acid copolymer in order to improve using of chalk in acrylic water-dispersion paints. It was proved the effectiveness and feasibility of chalk modification through mechanical activation in the presence of surfactants to improve the interaction between the acrylic polymer and fillers. The most suitable and effective chalk stamps were justified for use as fillers of water-dispersed paints, it was based on the analysis of chalk properties from different Ukrainian deposits. It was found that the surface of sedimentary chalk reveals relatively high polarity, which complicates the process of its dispersing in the polymers environment. In order to improve the quality of water-dispersion paints by increasing the degree of chalk surface hydrophobicity and improve its physical and chemical properties it was held mechanochemical modification of filler before entering into the paint composition. Rational quantitative parameters of lyophilic-lyophobic balance of sedimentary chalk surface were determined. The optimal concentration of modificators for achieving these parameters by mechanochemical modification was determined. It was proved that mechanochemical modification of chalk by aqueous solution of potassium methylsiliconate and solution of a sodium salt of an acrylic acid copolymer is accompanied by changes in their hydrophilic-lyophilic balance. The peculiarities of the interaction processes between pure chalk and modified chalk with acrylic filler were studied. The processes of interaction in systems of chalk with modifiers and acrylic film former are analyzed. It was shown the possibility of chemisorption of water-dispersion acrylic polymer on modified chalk surface, including by active groups of modificators which recorded on it. In this paper the quantitative parameters of the main characteristic bands responsible for the stretching vibrations of reactive groups of chalk and film former are determined. Maximum shift of the characteristic bands of the IR spectra and changes of their intensity are indicated. It is determined which of the investigated surfactants provide the most complete interaction of chalk with acrylic film former. The results demonstrate that the interactions of the modifiers, fillers, and film former are proceed in presence of adsorbed water and C=O linkages of chalk surface. The author suggests the use of modified chalk, which is characterized by the most complete interaction with the acrylic film former, as fillers for waterborne paints that provide higher performance properties of coatings. Rational composition of interior acrylic water-dispersed paints with modified chalk intended for work in areas with high and low load was defined by multi-objective optimization method. Technological and operational properties of acrylic water-dispersion paints were studied. It was experimentally confirmed that using of chalk modificated by aqueous solution of potassium methylsiliconate and solution of a sodium salt of an acrylic acid copolymer in acrylic water-dispersion paints improved properties of coatings: reduced water absorption and water wetting angles. A comprehensive assessment of commodity quality of water-dispersion paints with chalk fillers was conducted and its competitiveness was determined. The results of research made it possible to justify the use of modified chalk in acrylic water-dispersion paints, which coatings have improved physical and mechanical properties. Study of acquired scientific principles and approaches to create full water-dispersion paints and chalk modifying the development of principles, to improve their properties and extend the range of domestic mineral fillers for paints and varnishes were further developed. Results of research were tested in a production environment. The novelty of technical solutions was approved by patent for utility model.