Study of thickening polymeric compositions for printing fabric of blended fibers

. Thickening compositions of a new composition for printing mixed fabrics based on cotton and nitron fibers have been developed. The influence of the components of dampening compositions on the rheological properties of the composition depending on their concentration was studied. Established the development of a new composition of the thickening composition of its physico-chemical and rheological properties.


Introduction
For printing mixed fabrics, it should be noted that, especially natural and synthetic (cotton and nitrone) fibers with active dyes, the issue of choosing a thickener is important. Because, most traditional thickeners by nature and chemical structure are high molecular weight hydroxyl compounds, i.e. to polysaccharides, which are similar in chemical structure to cellulose. Based on production experiments, alginic acid salts correspond to the greatest positive properties, i.e. sodium alginate and synthetic thickeners [1].
During the processing of cotton fiber in the yarn, it is subjected to a number of mechanical impacts leading to the deterioration of its properties. Therefore, cotton fiber is referred to and the fabric based on it after the stage of dummon and bleach is printed using different ingredients.
As is known, in order to create a colorful pattern on a fabric using the existing technology, it is necessary to place the dye in a viscous system that is capable of ensuring its transition from an in-depth engraving or pattern grid to the fabric. A viscous system is a thickener. Thickeners are polymer solutions, multicomponent, highly structured disperse systems. Despite these requirements, they are not ideal. These thickeners do not meet the requirements in production mainly for two reasons: their high cost and sensitivity to hardness salts and pH.
There are such thickeners as Solvitose C-5, Emprint, Manutex because of the high cost makes it difficult to use them on a large scale in production. Therefore, the use of domestic products based on oxidized starch, PAA and K-4 preparation as thickeners when printing mixed fabrics with active dyes is interesting as an alternative to expensive imported thickeners. Therefore, it became necessary to study the effect of a new composition of thickening compositions on the printing properties of blended cotton and nitron fabrics. Oxidized starch, polyacrylamide, and K-4 were selected as thickening compositions [2].

Methods
When printing mixed textile materials with active dyes at domestic textile enterprises, starch cannot be used as a thickener. Because, when printing with starch hydrogels, low values of the degrees of dye fixation are obtained as a result of the chemical binding of the dye with a thickener, i.e. with starch and, as a result, the formation of hard-to-remove films, which greatly complicates the technological process of washing printed fabrics.
It is this circumstance that contributes to ensuring the stability of the color to physical and chemical treatments. In addition, as a result of printing, the active dye becomes part of the fiber macromolecule, as a result of which the fixation of the dye increases, leading to high resistance to wet processing, friction, color intensity and other external influences [3].
Despite significant achievements in the field of creating cotton fibers, success in this area is far from being exhausted, therefore the development of effective water-soluble compositions based on local raw materials suitable as a thickener in the process of printing mixtures based on cotton and nitron fibers is a very urgent task.

Results and discussion
When printing samples of mixed fabrics based on cotton and nitrone fibers at a ratio of 70:30, the following active dyes were respectively selected. These dyes are called bright red 5CX, remazol bright blue R, orange 2CT. It should be noted that the choice of dyes is due to the fact that the above active dyes are widely used for printing many fabrics, such as cotton, viscose and other mixed fibers, give a strong high-quality color that is resistant to the physical and chemical effects of printed patterns using the proposed thickener [4]. The influence of the components of dampening compositions on the rheological properties of the composition depending on their concentration was studied. The data obtained are shown in Table 1.
From the data obtained (Table 1) it can be seen that with an increase in the amount of PAA in the composition of oxidized starch, its viscosity, the degree of thixotropic reduction, and the yield strength change significantly. As can be seen from the Table, as a result, the development of a new composition of the thickening composition of its physico-chemical and rheological properties in relation to thickeners containing starch, carboxymethyl starch and Na-CMC becomes high. And in relation to thickeners of sodium alginate and solvitosis, the rheological properties of the developed composition become close. During the addition of a 6.0% oxidized starch of 1.0% PAA, the solution has a higher viscosity, the rheological properties change and the degree of thixotropic recovery is 85.9%, and the yield strength is 46.37 g / cm 2 .
In this regard, it represented the development of the technology of a new composition of thickening compositions for the printing of blended tissues based on cotton and nitron fibers. From the data shown in Fig. 1, it can be seen that the introduction into the composition of the finished 6.0% oxidized starch, 1% PAA and 1.5% K-4 (relative to the mass of the total solution) allows you to get a more viscous printing paint than without additive.
The cause of high viscosity, in our opinion, is the additional formation of supramolecular structures with hydrogen and intermolecular bonds between functional groups OK, PAA and K-4. Each type of links contributes to an increase in the stability of the starch of oxidized celastic [5].
The identified behavior of the developed thickening composition is very important to achieve the necessary viscosity during the operation of the printed machine. At the same time, in this case, the amount of thickety administered to the composition of the printed paint can be reduced by 15-17% by adding oxidized starch 1.0% PAA and 1.5% K-4. The pre-economic calculation of the receipt of printed paints on the basis of a 6% oxidized starch and compositive (obtained by the "man-made" method) of thickens showed that the introduction of 1.0% PAA and 1.5% K-4 in oxidized starch In general, it allows you to reduce costs in the production of thickening.
With the purpose of estimating the degree of destruction of the inner structures under the conditions of printing and analyzing the changes in these structures, when the components of the thickener are determined by rheological parameters for the studied compositions of various composition. Analyzing scientific and technical literature is established that when stuffing cotton tissues with active dyes there are some disadvantages due to the lack of a wide range of thickeners who could meet all the necessary requirements for the quality patterns obtained on the textile material. In this regard, it was an interest and justify the possibility of using water-soluble compositions based on oxidized starch (OK), polyacrylamide (PAA) and the drug K-4 as a thickener when putting up with active dyes, as well as expand the range of thickeners through the use of these promising types of polymers [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].

Conclusion
The experiments carried out showed that the components of thickening polymer compositions are compatible with selected active dyes. To determine the influence of components of thickening compositions on the quality and stability of the color, the printing quality parameters were estimated -the color saturation, the degree of fixation of the dye, the resistance to wet and mechanical treatments -stability to washing, to sweat and friction on generally accepted methods.