RU2433155C1 - Coating composition - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: coating composition as a base contains hydroxyl-containing polybutadiene rubber with a microstructure, %: 1,-4-trans 10-15 and 1,2-links 85-90, molecular weight 1250-3200 and content of hydroxyl groups 0.82-2.36%, isocyanate curing agent, polyisocyanate, urethane-formation catalyst and an additional mixture of isomers of 3,5-dimethylthio-2,4- toluylenediamine and 3,5-dimethylthio-2,6-toluylenediamine in ratio of 75.5-81:18-20 or a mixture of 3,5-diethyl-2,4-toluylenediamine and 3,5-diethyl-2,6-toluylenediamine in ratio of 75.5-81:18-20. ^ EFFECT: high strength of the coating. ^ 1 tbl

Description

The invention relates to compositions based on liquid hydrocarbon rubbers for the manufacture of sports field coatings, floors, roofing and waterproofing coatings.

A known coating composition, including oligodienediol - isoprene-butadiene copolymer, plasticizer, filler, trifunctional low molecular weight alcohol, urethane formation catalyst, 2,4,6-tri-tert-butylphenol, hardener polyisocyanate and additionally ethyl silicate (see patent RFF 2186812, C09D00, 1090900, C09D Publish. 08/10/2002).

Known composition for coatings, including low molecular weight hydroxyl-containing rubber - a copolymer of isoprene and butadiene, polyisocyanate, a urethane formation catalyst, desiccant, filler, plasticizer, low molecular weight alcohol, pigment, alkyl phenol antioxidant and rheological additive (see Patent No. 09/09/196, RF Patent No. 22/178, No. 229, patent no. November 27, 2006, Bull. No. 2).

The disadvantage of these compositions is the low strength of the cured elastomeric coatings.

A known coating composition comprising oligobutadiene diol, a plasticizer, a mineral filler, a trifunctional low molecular weight alcohol, a urethane formation catalyst, 2,4,6-tri-tert-butylphenol, polyisocyanate and ethyl silicate (see RF patent 2190002, C09D 175/08. Publish. 09.27.2002. )

The disadvantage of this composition is the low strength of the elastomeric material for coatings.

The closest solution to the proposed invention (prototype) is a composition (see RF patent 2285026, C09D 175/14. Publ. 10.10.2006, Bull. No. 28), including isocyanate hardener - polyisocyanate, urethane formation catalyst and base, hydroxyl-containing polybutadiene rubber microstructure %: 10-18 1,4-cis, 18-28 trans-1,4, 58-70 1,2-units with a molecular weight of 2100 and a hydroxyl content of 1.2-1.9%, or a molecular weight of 3000- 3200 and a content of hydroxyl groups of 0.88-1.36%, or a molecular weight of 5000-5300 and a content of hydroxyl groups of 0.6-0.8% with the corresponding oshenie components, parts by weight:

The specified hydroxyl-containing polybutadiene rubber one hundred Isocyanate Hardener - Polyisocyanate 10-36 Urethane Catalyst 0.001-3.0

Additionally, the composition may contain:

Desiccant (calcium oxide, gypsum, cement) 5-20 Filler (chalk, talc, lime-screenings, kaolin) 50-250 Plasticizer 20-100 Low molecular weight alcohol with at least two 1-8 hydroxyl groups or component AF-2 Alkylphenol Antioxidant 0.5-2.0 Pigment 0.5-10.0 Rheological properties modifier - surfactant 0.5-5.0

Coatings from this composition are characterized by an insufficient level of strength properties. This is due to the heterogeneous structure of the rubber, which affects the reactivity, compatibility of the rubber with the isocyanate hardener, the density of cross-linking, the nature of the relaxation processes and the relaxation time spectrum of the cured products.

The technical result of the present invention is to increase the level of strength properties, especially the strength of the coating.

The technical result is achieved in that the coating composition comprising an isocyanate hardener - polyisocyanate, a urethane formation catalyst and a base - hydroxyl-containing polybutadiene rubber, characterized in that microstructure rubber is used,%: 1,4-trans 10-15 and 1,2-units 85-90, a molecular weight of 1250-3200 and a hydroxyl content of 0.82-2.36%, and additionally a mixture of isomers of 3,5-dimethylthio-2,4-toluylenediamine and 3,5-dimethylthio-2,6-toluene diamine in the ratio 75.5-81: 18-20 or a mixture of 3,5-diethyl-2,4-toluylenediamine isomers and 3,5-diethyl-2,6-toluenediamine in a ratio 75,5-81: 18-20 in the following ratio, mass parts .:

The specified hydroxyl-containing polybutadiene rubber one hundred Isocyanate Hardener-Polyisocyanate 12-36 Urethane Catalyst 0.01-1 A mixture of isomers of 3,5-dimethylthiotoluylene diamine or A mixture of isomers of 3,5-diethyltoluylene diamine 0.7-8.4

The essence of the invention lies in the fact that the structure of the hydroxyl-containing rubber used is homogeneous, the content of 1,2-units reaches 85-90% with a small amount of 1,4-trans (10-15%) and the complete absence of 1,4-cis units. Allyl-type primary terminal hydroxyl groups are highly reactive in reactions with isocyanates. A homogeneous microstructure with predominant 1,2-units increases the compatibility with the isocyanate hardener based on diphenylmethanediisocyanate, the compatibility and solubility of the mixture of these isomers. This increases the speed, depth of chemical interaction and the degree of crosslinking of the cured products.

The combination of rubber, polyisocyanate and aromatic diamine used can increase strength due to the formation of additional vulcanization structures of a physical intermolecular nature. The energy of the intermolecular interaction of such physical bonds is comparable with the interaction energy of inter-site flexible butadiene blocks with a 1,2-unit structure, which improves the morphology of the structure of the crosslinked polymer, narrows the range and spread of the stress relaxation time by reducing the variety of structures and types of relaxation transitions. All this contributes to increased strength due to the redistribution of stresses, the elimination of overvoltages and the uniform redistribution of stresses on a larger number of chains and segments.

Hydroxyl-containing polybutadiene rubber obtained by anionic polymerization by the method of "live chains", is currently used as a film-forming in the paint industry and as a modifying additive in compositions based on solid rubbers, chemical structure [http: //www.Nisso PB.com.]:

Properties depend on the molecular weight of the rubber:

Marking G-1000 G-2000 G-3000 The average molecular weight of rubber 1250-1650 1800-2200 2600-3200 Microstructure,%: 1,2-vinyl, min 85 85 90 1,4-trans max fifteen fifteen 10 Brookfeld viscosity at 45 ° C, Pa * s 3-10 8-25 25-45 Hydroxyl number,% 2.06-2.36 1.06-1.67 0.88-0.94 Density at 25 ° С, g / cm ³ 0.88 0.88 0.88

Polyisocyanates, in particular polymethylene phenyl isocyanates based on 4,4'-diphenylmethane diisocyanate (TU-6-03-375-75, 113-03-38-106-90, 113-03-603-86, 2224-152, are used as isocyanate hardener -04691277-96) or their imported analogues: desmodur, suprasek 5005, MR200 million and others with the content of isocyanate groups 29-32%.

Organometallic compounds or tertiary amines, for example, tin dibutyldylaurinate (TU-6-02-818-73), tin octoate, dimethylbenzylamine (TU-6-09-2974-78) and other organotin and amino compounds used in chemistry, are used as a urethane catalyst. polyurethanes.

The aromatic diamines used are a mixture of isomers of 3,5-dimethylthio-2,4-toluylenediamine and 3,5-dimethylthio-2,6-toluylene diamine in a ratio of 75.5-81% or 3,5-diethyl-2,4-toluylene diamine and 3,5-diethyl-2,6-toluylenediamine in the same ratio.

For the manufacture of the coating composition, mixing equipment is used to ensure uniform distribution of the polyisocyanate and the urethane formation catalyst in the rubber and to obtain a homogeneous mixture.

The invention is illustrated by the following example:

Example 1. 100 g of rubber, 12 g of polyisocyanate, 1.4 g of 3,5-dimethylthiotoluylenediamine are mixed into a mixer with a 1 L volume mixer, stirred for 5 minutes, then 0.1 g of urethane formation catalyst is added and stirred for another 1 minute.

The resulting mixture is applied to flat forms and kept at a temperature of at least 20 ° C for 3-5 days.

Similarly prepare compositions of composition 2-14 according to example 1.

The composition and properties of all investigated compositions are shown in table 1.

Coating samples were tested according to GOST 263-93, GOST-270-75.

From the data of table 1 it can be seen that the use of the claimed hydroxyl-containing polybutadiene in combination with a polyisocyanate, aromatic diamine and a urethane formation catalyst as a basis for the composition makes it possible to increase the strength of the coatings.

Table 1. Composition and properties of coating compositions Name of components and indicators Composition in parts by weight and properties of compositions one 2 3 four 5 6 7 8 9 10 eleven 12 13 fourteen Prototype Pat RF 2285026 1. Hydroxyl-containing polybutadiene rubber with a molecular weight 1250 one hundred 2100 one hundred 3200 one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred one hundred 2. Hydroxyl-containing polybutadiene rubber with a molecular weight of 3000 Krasol brand one hundred 3. Polyisocyanate 12 17 21 26 31 36 21 thirty 17 21 12 fifteen 10 42 12 4. Urethane catalyst 0.1 0.05 0.01 0.01 0.01 0.05 0.01 0.01 0.01 0.01 one 0.01 2 0.001 0.1 5. A mixture of isomers of 3,5-dimethylthiotoluene diamine 1.4 3 4.3 5.7 7 8.4 3 3 0.7 3 0.4 9 6. A mixture of isomers of 3,5-diethyltoluylene diamine 3 4.3 7. Glycerin 2 Conditional tensile strength, kgf / cm ² 16 19 thirty 41 43 40 24 27 twenty 29th fifteen eighteen 9 8 12 Relative extension, % 250 240 220 200 180 150 230 210 230 210 270 190 350 380 one hundred Hardness, Shore A, conv. units 44 48 fifty 52 54 57 51 55 48 51 44 54 32 34 44 Notes in the formulations: 1-10, 12, 14 used tin dibutyldylaurinate; dimethylbenzylamine was used in formulations 11, 13

When the content of polyisocyanate is less than 12 parts by weight leads to a decrease in the level of the complex of strength properties due to a significant deviation of the NCO: OH ratio from stoichiometric and a decrease in the crosslinking density. With large quantities of polyisocyanate more than 36 parts by weight strength properties are also reduced due to the excess of isocyanate groups, the tendency to foaming and increase the rigidity of the cured product.

Similarly, the amount of the mixture of the used isomers is affected when the amount is less than 0.7 parts by weight. and in large quantities over 8.4 wt.h. stoichiometric equilibrium is violated towards a deficiency or excess of hardener.

The amount of urethane formation catalyst has practically no effect on the physicomechanical characteristics and only controls the cure rate of the compositions.

Thus, the advantage of the coatings of the proposed composition is higher strength, which serves to increase the service life.

Claims (1)

Composition for coatings comprising an isocyanate hardener - polyisocyanate, a urethane formation catalyst and a base - hydroxyl-containing polybutadiene rubber, characterized in that the microstructure rubber is used,%: 1,4-trans 10-15 and 1,2-units 85-90, molecular weight 1250 -3200 and a content of hydroxyl groups of 0.82-2.36% and an additional mixture of isomers of 3,5-dimethylthio-2,4-toluylene diamine and 3,5-dimethylthio-2,6-toluene diamine in a ratio of 75.5-81: 18 -20 or a mixture of 3,5-diethyl-2,4-toluylene diamine and 3,5-diethyl-2,6-toluene diamine in a ratio of 75.5-81: 18-20 in the following the ratio of components, parts by weight:
The specified hydroxyl-containing polybutadiene rubber one hundred Isocyanate Hardener - Polyisocyanate 12-36 Urethane Catalyst 0.01-1 A mixture of isomers of 3,5-dimethylthio-2,4-toluylenediamine and 3,5-dimethylthio-2,6-toluylene diamine or mixture 3,5-diethyl-2,4-toluylene diamine and 3,5-diethyl-2,6- toluylene diamine in the ratio of 75.5-81: 18-20 0.7-8.4