RU2478676C1 - Protective coating composition based on chlorosulphonated polyethylene - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to protective coating compositions based on chlorosulphonated polyethylene for protecting metal and concrete from external action. The protective coating composition based on chlorosulphonated polyethylene contains pigments, organic solvents, polymeric petroleum resin as a modifying additive and curing agent and zinc phosphate.

EFFECT: composition has high covering capacity and viscosity, and coatings made from said composition have improved waterproofing and protective properties.

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Description

The invention relates to protective paint compositions for coatings based on chlorosulfonated polyethylene (ChSPE), pigments and target additives (anti-corrosion fillers and modifiers) for protecting metal and concrete from external influences.

From a number of single-component materials based on HSPE, which are most often used in construction during painting works, the enamel ХП-7120 “Razvetok” TU 2312-012-54743950-2005 is known, used to protect the outer surfaces of stationary equipment and various structures made of metal, wood and concrete exposed to atmospheric conditions in a temperate, cold and tropical climate.

The disadvantage of this enamel is its low viscosity with a high solvent content and the small thickness of the single-layer coating, which does not provide the necessary hiding power and protective properties.

By protective properties, the closest analogue is a paints and varnishes based on chlorosulfonated polyethylene containing pigment, solvent and target additives (ENAMEL HP-7142 TU 2313-022-54743950-2005) for corrosion protection of metal and concrete in the construction of bridges, power plants , engineering, hydraulic engineering, port and various industrial facilities (including in chemical, metallurgical and other industries). This enamel is used in combined protection systems as a finish layer or as an independent coating of metal and concrete. The resulting protective coating has high weather resistance, water resistance, chemical resistance to aggressive environments of acid and alkaline nature, withstands the static effects of solutions of acids and alkalis.

However, the significant disadvantages of this composition include a high content of solvents - volatile organic compounds, which allows to obtain coatings of only a small thickness, and, due to low hiding power, requires repeated application of paint and varnish on the painted surface. In addition, the low viscosity of the HP-7142 enamel contributes to the formation of sagging when painting vertical structures.

The aim of the invention is the development of technologically advanced one-component protective paint compositions for coatings based on HSPE with increased hiding power and viscosity in terms of basic indicators that are not inferior to the prototype, but superior in waterproofing and protective properties.

Another significant objective is to reduce the cost of the composition by reducing the content of the traditional expensive and toxic organic solvent (xylene) and reducing energy consumption in its manufacture.

The result is achieved in that the protective composition for coating based on HSPE, containing pigments, organic solvents and a modifying additive, according to the invention, contains petroleum polymer resin (NPS) as a modifying additive and a curing agent, with the following components (wt.%):

chlorosulfonated polyethylene 7.5-8.0

petroleum resin 9.0-11.0

pigments 4.0-5.5

zinc phosphate 4.0-6.0

organic solvents up to 100.

-метилстирола) марки А. Внешний вид - куски неопределенной формы, массой не более 1 кг, от светло-коричневого до темно-коричневого цвета. Температура размягчения 89°С, цвет по йодометрической шкале 50 мг J₂/100 см³, массовая доля летучих веществ 0,4%, кислотное число 1,0 мг КОН/г.The petroleum polymer resin (TU 2451-089-05766801-99) is a copolymerization product of fractions of the liquid C9 pyrolysis products (styrene, vinyl toluene, dicyclopentadiene, idene,

-methyl styrene) grade A. Appearance - pieces of an indefinite shape, weighing no more than 1 kg, from light brown to dark brown. Softening point 89 ° C, the color of iodine scale 50mg J _2/100 cm ^3, the mass fraction of volatile matter of 0.4%, an acid number of 1.0 mg KOH / g.

The pigments used were titanium dioxide of the P-02 grade (GOST 9808-84), red iron oxide pigment of the K brand (TU 6-10-602-86) and zinc phosphate (TU 2329-002-13938162-2004).

KhSPE Haipalon brand (molecular weight 20,000, mass fraction of chlorine,% - 30 + 4, mass fraction of sulfur,% - 1.8 + 0.5) in the form of a 10% solution in organic solvents.

Toluene (GOST 14710-78) and white spirit (GOST 3134-78) in a ratio of 3: 1 parts by weight were used as organic solvents. respectively.

The proposed composition was prepared in predetermined proportions (Table 1) in two color options.

Table 1 Ratio of components Name of components Content,% HP-1 white Content,% CP-2 red-brown one 2 3 one 2 3 one HSPE (10% solution) 7.5 7.7 8.0 7.5 7.7 8.0 2 Petroleum resin 9.0 10.0 11.0 9.0 10.0 11.0 3 Titanium dioxide 4.0- 4.85 5.5 - - - four Red iron oxide pigment - - - 4,5-5,5 4.85 5.5 5 Zinc phosphate 4.0- 5,0 6.0 4,5 5,0 5.5 6 Organic solvents Up to 100 Up to 100

To study the protective properties of coatings, the proposed composition was applied to glass, metal and concrete surfaces.

Samples of protective compositions were prepared by dispersing the dry components of the mixture in a pre-prepared 10% solution of CSPE in a laboratory bead mill of the LDU-3 LDM type at 1000 rpm for 60 min. The completion of the process was monitored using a Klin device to achieve a pigment fineness of 20 μm.

Tests of technological properties and protective properties were carried out in accordance with the requirements of GOST for paints and varnishes (Table 2).

table 2 Qualitative indicators No.
p / p The name of indicators Determination method Prototype Khp-1 white KP-2 cr.-brown. one 2 3 one 2 3 one 2 3 four 5 6 7 8 9 10 one Mass fraction of nonvolatile substances,%, no more GOST 17537, section 1 30 ± 5 34 35 36 36 35 37 2 Drying time to degree 3 at a temperature of (20 ± 5) ° С, h, no more GOST 19007 one 0.5 0.5 0.5 0.5 0.5 0.5 3 Conventional viscosity at a temperature of (20 ± 0.5) ° С using a B3-246 viscometer with a nozzle diameter of 4 mm, s, no less than GOST 8420 35 ± 5 55 58 59 60 59 61 four Spreading rate of the dried film, g / m ² GOST 8784-75 85 80 82 79 75 76 78 5 The degree of milling, microns, not more GOST 6589 twenty twenty twenty twenty twenty twenty twenty 6 Adhesion coating score According to GOST 15140-78 * one one one one one one one 7 The strength of the film upon impact with a U-1 device, rel. units According to GOST 4765 fifty fifty fifty fifty fifty fifty fifty

one 2 3 four 5 6 7 8 9 10 8 Film elasticity in bending, mm, not more than According to GOST 6806-73 one one one one one one one 9 Coating hardness after 7 days (according to TML-3), not less than According to GOST 5233-89 0.25 0.3 0.31 0.32 0.35 0.36 0.34 10 Resistance to static action of water at a temperature of (20 ± 2) ° С, h According to GOST 9.403-80 method A 48 60 58 62 60 64 56 eleven Resistance to static action of 5% alkali solution at a temperature of (20 ± 2) ° С, h According to GOST 9.403-80 method B 24 24 25 26 24 26 28 12 Resistance to static effects of Hcl at a temperature of (20 ± 2) ° C.h According to GOST 9.403-80 method A 36 36 37 38 36 37 38

Waterproofing properties were determined by the following method:

concrete samples painted in two layers and dried for 24 hours (20 × 20 × 20 mm), previously weighed on an analytical balance, were placed in desiccators with increased humidity of 85-90% and kept at T = 20 ± 2 ° С for 30 days, periodically weighing and comparing the change in mass with a control sample. The results showed that when protecting the samples with the developed compositions of the protective composition, the waterproofing properties increase by 15-18%.

Thus, the protective properties, as well as hiding power and viscosity, of the proposed compositions KP-1 and KP-2 differ from the prototype in increasing the hardness and resistance to water. This, obviously, can be explained by the reactivity of CSPE (the content of polar -SO ₂ Cl- and -CL- groups), which are involved in the formation of film coatings by interaction with oxygen-containing NPS groups.

In addition, it should be noted the increase in the adhesive strength of the coatings of the proposed composition due to the interaction of the polar groups of adhesives and the reaction centers of the substrates (physical bond network).

The obtained results confirm the feasibility of modifying CSPE with an oil-polymer resin, which made it possible to develop formulations of one-component protective compositions for coatings based on it, which are characterized by improved technological properties, such as drying time, high hiding power. This ensures its uniform application and obtaining smooth, semi-gloss coatings having higher values of adhesion and hardness, superior to the properties of the prototype. Of particular note is their waterproofing properties and the ability to "heal" microcracks, which is relevant for restoration or repair construction work.

In addition, the use of NPS as a modifier and curing agent made it possible to partially replace (20–25%) expensive CSPE, reduce the amount (up to 20%) of toxic solvents, and halve the drying time of the protective coating composition, which reduces its cost, and also contributes to solving environmental problems of environmental protection (reduction of toxic emissions from solvents).

Claims (1)

A protective composition for coatings based on chlorosulfonated polyethylene containing pigments, organic solvents and a modifying additive, characterized in that it contains a petroleum polymer resin as a modifying additive and a curing agent in the following components, wt.%:
chlorosulfonated polyethylene 7.5-8.0 petroleum resin 9.0-11.0 pigments 4.0-5.5 zinc phosphate 4.0-6.0 organic solvents: up to 100