CC BY
11
Yuldosheva Ozoda, candidate of technical Sciences, associate professor of Tashkent Institute of Textile and Light Industry, Uzbekistan, Tashkent Karimov Sardorbek Khojiboevich, Ph.D., in chemical sciences, senior lecturer Tashkent Institute of Textile and Light Industry,
Uzbekistan, Tashkent E-mail: sskarim80@mail.ru Rafikov Adham Salimovich, doc. chem. sci., professor Tashkent Institute of Textile and Light Industry,
Uzbekistan, Tashkent E-mail: asrafikov@mail.ru
PHYSICAL AND CHEMICAL PROPERTIES OF THE IMPARTED COPOLYMERS OF COLLAGEN AND POLYACRYLIC ACID
Abstract: Some physicochemical properties of synthesized graft copolymers of crude skin and polyacrylic acid are determined. The dependence of molecular weight, solubility, density and thermal properties of copolymers on the ratio of components and synthesis conditions was established.
Keywords: collagen, acrylic monomer, initiator, graft copolymers, inoculation.
Among various ways of copolymerization the grafting as a method of synthesis of composition high-molecular substances and materials of a special purpose has special value [1-8]. Establishment of regularities of receiving, physical and chemical and mechanical characteristics of graft copolymers of natural polymers with the functional and fissile monomers, taking into account specific properties of polymeric compositions, is an urgent problem of chemistry and polymer technology. Researches of regularities and the mechanism of synthesis of graft copolymers and on receiving reinforced films on the basis of a collagen and the poly(acrylic acid) [9-11] are earlier conducted. The real work is devoted to definition of dependence of a molecular mass, solubility, density and thermal properties of copolymers from a ratio of components and conditions of synthesis, processes of the copolymers occurring when heating.
Object ofa research is collagen, the ethylene carboxylic acid (ECA) and the potassium persulphate (PP). For receiving collagen solution wastage of a skin of animals is cut on pieces by the Z-4 sizes of mm and is located in capacity. In capacity 5% solution of sodium hydroxide at a mass ratio is poured a skin: solution-1:4. Pieces of a skin bulk up in alkali liquor within 72-24 clocks. Then solution is mixed before formation of the homogeneous mass, warming up if necessary, up to the temperature of 60 of oC. Solution is sifted through a bolter the sizes of cells of 0.05-0.1 mm. Add an acetic acid for the purpose of neutralization to screened solution torn: 7 + 0.2.
Potassium persulphate - K2S2O8, the initiator of polymerization, shallow crystals of white color, is well dissolved in water.
The acrylic emulsion - milky-white liquid with a slight cream shade without visible stratification. pH =6.0-8.5. the viscosity ratio not less than 1.75 mass fraction of a residual monomer (acrylate methyl) of no more than 0.35%.
Synthesis of graft copolymer of a collagen was carried out in the three-necked flask supplied with a mixer, the thermometer and a reflux condenser in nitrogen current. Solution of a collagen, joint stock company and the personal computer loaded into a flask, mixed in the thermostat. On reaching particular time the flask was taken out from the thermostat, cooled to ambient temperature, the reaction mixture was poured out in a glass with ethanol. The residual monomer and homopolymer are dissolved in ethanol, and copolymer is not dissolved. The received copolymer was washed out several times ethanol and dried up to the constant weight in desiccators.
The results of scientific research have shown that fabrics recommended for use as fire-resistant materials change their properties over time, that is, fire of the tissue is observed in the event of a fire. The main reason for this is the incomplete penetration of antiprin into the tissue, as well as the fact that methods of imparting fire resistance to the material with the recommended flame retardants have not been investigated.
A disadvantage of the known method is not the strength of the bonding of the impregnated flame retardant composition to the textile substrate, which results in loss of the flame retardant properties of the material being processed [1].
To improve the fireproof properties of the material, taking the basis of collagen, the technology of absorbing into the fabric was developed. To improve the interaction of the surface of the tissue with the flame retardant composition, several methods of pretreating the tissue have been tested [2].
The first way, textile material was previously treated with 0.5%, 0.75%, 1%, 2% and 3% sodium hydroxide solution.
The second way, textile material was preliminarily treated with 0.5%, 0.75%, 1%, 2% and 3% sodium sulfate salt, based on the weight of the fabric solution of sodium hydroxide.
The third way, the textile material was previously treated with 0.5%, 0.75%, 1%, 2% and 3% surfactant solution 0P-10.
The fourth way, textile material was previously treated with 0.5%, 0.75%, 1%, 2% and 3% hydrochloric acid, taken with respect to the weight of the tissue.
Processing is carried out in the following technological sequence:
Impregnation (according to the selected mixture), T = 18-200 C, time 30-60 seconds. Spin 80-90%. Rinse (in clean cold water), then squeeze (until the remainder is 5-10%). Drying at 60-800 °C, the time is 10-15 minutes.
After the processes were carried out according to a given technological sequence, the fabrics obtained by each method were impregnated with a flame retardant composition of the same composition. The composition of the composition contained acrylic emulsion, polyacrylamide, carbamide, boric acid, ammonium hydrogen phosphate. To assess the effect of pretreatment, the tissue was exposed to direct fire. The results of the tests are shown in (Table 1).
The test results clearly demonstrate the advantages or disadvantages of one or another pre-treatment method. Treatment with a solution of sodium sulfate and a surfactant has little effect on the fire resistance of the fabric. Treatment with a solution of hydrochloric acid is generally not acceptable the tissue is destroyed after treatment. A positive result is the treatment with a solution of sodium hydroxide. Some samples do not ignite even with prolonged exposure to direct fire.
The test results clearly demonstrate the advantages or disadvantages of one or another pre-treatment method. Treatment with a solution of sodium sulfate and a surfactant has little effect on the fire resistance of the fabric. Treatment with a solution of hydrochloric acid is generally not acceptable, the tissue is destroyed after treatment. A positive result is the treatment with a solution of sodium hydroxide. Some samples do not ignite even with prolonged exposure to direct fire.
Preliminary alkali treatment of the tissue allows dissolving waxy substances present on the surface of the tissue, which prevents the penetration of the fire retardant composition into the interior of the tissue, and subsequent washing allows them to be removed, resulting in the surface of the tissue being cleaned. Due to this, the fire retardant composition is well impregnated with a cloth, its strong binding to the textile base is achieved [3].
He processed material at a temperature of 18-20 °C for 30-60 seconds is impregnated with a 2-3% aqueous solution of alkali, for example, sodium hydroxide, squeezed to a residue of80-90% moisture. Then washed in cold water, squeezed to a residue of 5-10% moisture, dried for 10-15 minutes at about 80-100 °C. After that, the treated material is impregnated with a flame retardant composition containing the following components: 3-5% boric acid, 10-15% acrylic emulsion, 20% collagen solution 12-18 ml, 0.02-0.025% potassium persulfate, the balance water.
Table 1. - Dependence of resistance to direct fire from tissues treated with a flame retardant composition from the pretreatment method
Substance pretreatment Concentration of substance and test result
0.5% 0.75% 1% 2% 3%
Sodium hydroxide The fabric caught fire after 20 sec The fabric caught fire after 20 sec The fabric caught fire after 30 sec The fabric did not catch fire The fabric did not catch fire
Sodium sulfate The fabric caught fire after 5 sec The fabric caught fire after 5 sec The fabric caught fire after 6 sec The fabric caught fire after 10 sec The fabric caught fire after 15 sec
Surface-active agent The fabric caught fire after 5 sec The fabric caught fire after 10 sec The fabric caught fire after 10 sec The fabric caught fire after 15 sec The fabric caught fire after 20 sec
Hydrochloric acid Observed fabric destruction
Boric acid and collagen solution serve as a fire-resistant component, acrylic polymer-water-insoluble film-former and binder. Potassium persulfate serves to form active sites of graft copolymerization.
Impregnation with flame retardant composition is carried out at 40-50 °C for 30-60 seconds, then it is wrung out, followed by pressing to a humidity of 5-10%, then for 10 minutes it is subjected to heat treatment at 120-130 °C.
Various combinations of substances were tested, the most studied of which are presented in (Table 2).
The tests carried out at the boundary values of the concentration of the components allow us to conclude that when the concentration of acrylic emulsion is less than 10%, boric acid is less than 3% and a solution of collagen is less than 12%, the fire resistance of textile materials deteriorates. With an increase in the concentration of acrylic emulsion above 15%, boric acid above 5% and a collagen solution above 18%, the fire resistance does not change, but the rigidity of the textile material increases [4].
Table 2.- The composition dependence of the
Another important aspect is that the composition of the antiprin used to impart fire resistance to the fabric should not be poisonous. In addition, the fuel must also be harmless. If the composition of the antirene is not poisonous, this will expand the scope of its application. Given that the proposed flame retardant is a natural product, we can say that it meets the above requirements.
One of the characteristic features of fires in textile enterprises is a sharp increase in temperature at the beginning of the fire and the emission of thick smoke. This increase in temperature and thick smoke does not give employees the opportunity to extinguish the fire at the initial stage.
fire retardant treatment and the treated tissue
The substance in the composition The number of the composition and the amount of su bstances in it
1 2 3 4
Boric acid 3 g 5 g 10 g 5 g
Carbamide 5 g 5 g 10 g
Acrylic emulsion 5 ml 10 ml
Polyacrylamide, 3% solution 10 ml 20 ml 20 ml
Collagen 20 ml 20 ml 40 ml
Ammophos 5g
Test result The cloth caught on fire The cloth caught on fire after 10 sec. The fabric did not catch fire The fabric did not catch fire
The smoke emitted during combustion consists ofsubstanc- event of a fire, oxygen is sharply absorbed and the level of oxygen es called "normal gas" (oxygen, nitrogen, carbon dioxide, water in the air decreases. Due to lack of oxygen, a person does not feel vapor and carbon monoxide (II) or carbon monoxide). In the these changes physically and can not take the necessary measures.
Table 3.- The results of testing samples of textile materials for fire resistance
№ The dimensions of the sample, mm The mass of the sample, м: g. Mass loss, % Time of exposure to combustion, sec. Ignition time, sec. The result
Before the test After the test
1. 2.8-10 2.35 2.1 11 10 3 Smolder
2. 2.8-10 2.4 2.2 8 10 - Does not burn
3. 2.8-10 2.6 2.5 4 10 - Does not burn
4. 2.8-10 2.75 2.6 5 10 - Does not burn
5. 2.8-10 2.9 2.7 7 10 - Does not burn
prototype 12-13
The toxicity of carbon monoxide, released from the combustion of products, is that, when combined with hemoglobin, it forms carboxyhemoglobin. In this case, there is a shortage of oxygen in the human body. If the level of carbon monoxide in the inhaled mixture exceeds 0.1%, a person begins to feel bad. If 0.5% of carbon monoxide is
contained in the air and the person breathes this air, it results in death in 20-30 minutes, if 1% of carbon monoxide (II) is present, then within 1-2 minutes. When studying the burning of loose cotton waste, the concentration of gases in the mine was: nitrogen 78.9%, oxygen 19%, carbon monoxide 1.7%, and carbon oxide 0.4% [5].
References:
1. Kolya H., Tripathy T.J. Grafted polysaccharides based on acrylamide and N, N-dimethylacrylamide: preparation and investigation of their flocculation performance // Appl. Polym. Sci. 2013.- 127,- No. 4.- P. 2786-2795.
2. Okieimen F. E. Preparation, characterization, and properties of cellulose-polyacrylamide graft copolymers // J. Appl. Polym. Sci. 2003.- 89,- No. 4.- С. 913-923.
3. Bacer Burcu, Demirel Gokgen Birlik, Agik Leyla, Qaykara Tuncer. Preparation of comb type grafted hydrogeis composed of polyacrylamide and chitosan and their use for DNA adsorption // J. Appl. Polym. Sci. 2009.- No. 4.- С. 1862-1868.
4. Synthesis and aggregation bepaheir of chitoeligosaccharide - based biodegradable graft copolymers. Gao Ke - Jing, Li Guangtau, Shi Hongwei, Lu Xinping, Gao Yangbin, Xu Bo - Qing // J. Polym. Sci. A. 2008.- 46,- No. 14.- С. 4889-4904.
5. Luo H., Hu Л., Zhu Y., Wu Y., Zhang S., Fan Y., Ye G.J. Mechanically adaptive cellulose-poly(acrylic acid) polymeric composites in wet-dry cycles // Appl. Polym. Sci. 2013.- 127,- No. 1.- P. 675-681.
6. Zhong Jin-Feng, Chai Xin-Sheng, Fit Shi-Yu. Homogeneous grafting poly (methyl methacrylate) on cellulose by atom transfer radical polymerization // Carbohydr. Polym. 2012.- 87.- No. 2.- P. 1869-1873.
7. The Way of the reception collagen containing matrixes for immobilization biologically active material. The Stalemate. 2478299 Russia. Titov E. I., Apraksina S. K., Mitaseva YU. F. and has others Declared. 27.05.2011; Opubl. 10.04.2013.
8. Васильев М. П. Коллагеновые нити, волокнистые и пленочные материалы: Монография.- СПб. СПГУТД, 2004.- 397 c.
9. Karimov S. Kh., Ibragimov A. T., Rafikov A. S., Askarov M. A. A Reinforced Film of Graft Copolymers of Collagen and Acrylates // International Polymer Science and Technology. 2015.- 44.- T 47-T 50.
10. Каримов С. Х., Тохиров Р. Ш., Абдувохидов Д. А., Абдурахманов У Н., Рафиков А. С. Получение коллагена и его привитая сополимеризация с акриловыми мономерами / / Меж. науч.- тех. конф. «Новое в технике и технологии текстильной и лёгкой промышленности». Витебский государственный технологический университет. Сборник научных статей, 2013.- 240 c.
11. Каримов С. Х., Набиев Н. Д., Рафиков А. С. Кинетические закономерности привитой сополимеризации акриловых мономеров с натуральным шелком // Узбекский химический журнал. 2015.- No. 2.- С. 23-26.
