SU857202A1 - Method of producing water-soluble film-producing agent - Google Patents

Description

(54) METHOD FOR OBTAINING WATER-SOLUBLE FILM-FORMING

The invention of othosit to obtain water-soluble film-forming agents based on maleic acid vegetable oils used for the manufacture of primers for metals. A known method for producing a water-soluble film-forming vegetable oil by maleinizacin followed by neutrising an adduct (male oil) with ammonia or another nitrogenous base 1. However, the resulting film-forming has a very air-drying ability. The closest in terms of technology to the present invention is a method of obtaining a water-soluble film-forming by circulating at 60-13 5 ° C low-line vegetable oil, such as flax, a nitrogenous base (ammonia or aliphatic amine) in the presence of a water-alcohol mixture 2. However, the method is used to obtain products of unstable prn storage, in addition, the resulting film-forming material is cured at 180 s and the coating based on it has insufficient tederdost, water resistance, and chemical resistance. The goal of the invention is to reduce the process temperature, decrease the curing temperature of the film-forming and improve the properties of a coating based on it. The goal is achieved by the fact that in the method of producing a water-soluble film-forming agent by treating maleinized linseed oil with a nitrogenous base in a hydroalcoholic medium, a mixture of hexamethylenediamine, ammonia and doda in a ratio of 9.2: 1.22: 12.98 or a mixture of hexamethylene diamine is used as the nitrogenous base, monoethylamine and water in a ratio of 9.2: 6.07: 12.33. The method is implemented as follows. Maleinated linseed oil is treated with a nitrogen base (aqueous mixture of hexamethylenediamine HMD and ammonia 11 or aqueous mixture of hexamethylenediamine and monostilamine MEA) at 18–20 ° C in the presence of a water – alcohol mixture (aqueous mixture of alcohols). Due to the heat of reaction, the temperature rises to 5060 C. 3 In the method, maleized flax oil, with a content of a minor anhydride of 20-25%, is used. Example 1. In a three-necked flask with a stirrer, a thermometer, and a reflux condenser, 40 g MLM (lightly dried linseed oil, an anhydride value of 116.3 kg con / g) and a previously prepared mixture of 18.4 50 g are charged at 18–20 ° C. % aqueous solution of HMD (9.2 g in terms of dry), 5 g of 24.4% aqueous solution of ammonia (1.22 g in terms of dry) and 105.2 g of 30% aqueous mixture of alcohols (propalic: butyl: ethyl cellosolve 1: 1: 1). The mixture is kept under stirring until complete dissolution. Due to the heat of reaction, the temperature rises to 55-60 ° C. Example 2. The process is carried out in the installation described in example 1. To 40 g of MLM, a mixture of 18.4 g of a 50% aqueous solution of HMD (9.2 g in terms of dry), 18.4 g of a 33% aqueous solution of MEA (6.07 g in terms of dry) and 106.5 g 30% aqueous alcohols (propyl: butyl: ethyl cellosolve: 1; 1) at 18-20 ° C. The reaction mixture is kept under stirring until dissolved. The reaction products are 30.4-30.6% solutions of salts of amido acids, diluted unhindered with water, have an acid number of 35.4-36.1 mg KOH / G (per solution) or 116-118.8 mg KOH / G (per 100% product) and amine number 43.2-43.7 mg KOH / g (per solution or 140.3-143 mg KOH / G (per 100% product). Viscosity of solutions 60-75 s by VO -4, and after dilution with water to 15% concentration, the viscosity decreases to 16-23 C. Coatings are obtained by applying 15% solutions by pouring onto glass plates and electroplating on steel plates, followed by curing at 120, 135 and 150 ° C. Pokry These have higher rates compared to coatings from aqueous solutions of MLM treated with ammonia only (Table 1). Curing of the coating withstands a blow of 50 kgf cm and has an elasticity of 1 mm. Water resistance of cured coatings: examples 1 and 2 (135 and 150 ° C) - 30 days without changing the appearance and without corrosion of the metal; by a known method (180 ° C) 20 days under the surface of the coating, isce: 1 drying after drying, 25 days - metal corrosion, 30 days - corroded 10-15% of the surface. Acid resistance in 15% sulfuric acid: the occurrence of pitting corrosion after 5 days in coatings by a known method; after 7 days, the coatings according to examples 1 and 2. Thus, the film-forming, obtained by a known method does not form at 120-150 ° C curable coatings (cured at 180 ° C), while in the proposed method, film-forming curable at 120-150 ° C with increased hardness, water resistance, acid resistance, which generally leads to simplification of the process and expansion of the range of film-forming. In tab. 1 shows the properties of the cured coatings, and table. 2 - product characteristics.

Dry residue,%

(solution)

Acid number, counting mg KOH / Gna 100%

product

(solution)

Amine number, counting Mi KOKl-IWy / o140.3-143

product) Viscosity of solutions according to VZ-4, with Diluting with water

table 2

30.1-30.3

30.2-30.4

34.9 35.1

115.2-116.1

115.5-116.2 29.8

30.1 98-98.7

99.3-100 Unlimited

Claims (1)

Claim A method of producing a water-soluble film-forming by treating maleinized linseed oil with a nitrogenous base in an aqueous-alcoholic medium, characterized in that, in order to reduce the temperature of the process ₄₅ , to lower the curing temperature of the ylene formation and improve the properties of the coating based on it, a mixture of hexamethylene amine is used as a nitrogenous base, ammonia and water in a ratio of 9.2: 1.22: 12.98 or a mixture of hexamethylenediamine, monoegylamine and water in a ratio of 9.2: 6.07: 12.33.