RU2546737C1 - Coating composition - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: coating composition includes low-molecular hydroxyl-containing butadiene-based caoutchouc, plasticiser, filler, an isocyanate hardener - polyisocyanate. As the caoutchouc it contains hydroxyl-containing polybutadiene caoutchouc or caoutchouc-copolymer of isoprene and butadiene and additionally contains an acrylate-containing cross-linking agent, selected from the line of methylmethacrylate, butylmethacrylate, dimethacrylic ether of triethyleneglycol and oligoetheracrylate MGF-9, a peroxide initiator and N,N,4-trimethylaniline.

EFFECT: increased hardness and strength of elastomers for coatings.

1 tbl, 1 ex

Description

The invention relates to compositions for coatings based on liquid rubbers intended for the device coatings of sports fields, floors, roofing and insulation coatings in construction.

A known coating composition, comprising an oligodienediol copolymer of isoprene and butadiene, a plasticizer, a filler, a trifunctional low molecular weight alcohol, a urethane formation catalyst, 2,4,6-tri-tert-butylphenol, a hardener polyisocyanate and additionally ethyl silicate (RF patent 2186812, Cubl 109/00. 10.08.2002).

Known composition for coatings, including low molecular weight hydroxyl-containing rubber - a copolymer of isoprene and butadiene, a polyisocyanate, a urethane formation catalyst, a desiccant, a filler, a plasticizer, a low molecular weight alcohol, a pigment, an alkyl phenol antioxidant and a rheological additive (Patent RF09L68/149 / Publish. November 27, 2006, Bull. No. 2).

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

Known composition for coatings, including oligobutadiene diol, plasticizer, mineral filler, trifunctional low molecular weight alcohol, urethane formation catalyst, 2,4,6-tri-tert-butylphenol, polyisocyanate and ethyl silicate (RF patent 2190002, C09D 175/08. Publ. September 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 (RF patent 2434916, C09D 175/14, C09D 109/00. Published on 11/27/2011) comprising an isocyanate hardener - polyisocyanate, a urethane formation catalyst, a base - hydroxyl-containing polybutadiene rubber of the microstructure,%: 1,4-trans 10-15 and 1,2-links 85-90, a molecular weight of 1250-3200 and a hydroxyl content of 0.82-2.36%, a plasticizer, a filler and an antioxidant in the following ratio of components, parts by weight :

The specified hydroxyl-containing polybutadiene rubber one hundred Plasticizer 40-140 Filler 80-340 Antioxidant 1-2 Polyisocyanate 12-38 Urethane Catalyst 0.01-1

Additionally, the composition may contain a trifunctional low molecular weight alcohol 1-16 wt.h.

Represented in the prototype hydroxyl-containing polybutadiene rubber is a low molecular weight hydroxyl-containing rubber based on butadiene.

Coatings from this composition are characterized by insufficient hardness and strength.

The present invention is to develop a composition for coatings based on low molecular weight hydroxyl-containing rubber with improved strength characteristics.

The technical result is to increase the hardness and strength of elastomers for coatings.

The technical result is achieved in that the coating composition, including low molecular weight hydroxyl-containing rubber based on butadiene, a plasticizer, a filler, an isocyanate hardener - polyisocyanate, contains rubber as a hydroxyl-containing polybutadiene rubber or an isoprene-butadiene rubber-copolymer, and additionally contains an isoprene-butadiene rubber and an acrylate-containing agent from a series of methyl methacrylate, butyl methacrylate, triethylene glycol dimethacrylic ester and MGF-9 oligoester acrylate, peroxide init ator and N, N, 4-trimethylaniline in the following ratio of components, parts by weight:

The specified hydroxyl-containing rubber one hundred Plasticizer 40-130 Filler 50-300 Isocyanate Hardener - Polyisocyanate 8-20 Acrylate Crosslinking Agent 5-100 Peroxide initiator 0.05-5 N, N, 4-trimethylaniline 0.01-0.1

The essence of the invention lies in the fact that the presented hydroxyl-containing rubber is additionally crosslinked by double bonds with an acrylate-containing agent. Double bond crosslinking of the rubber is initiated and activated by peroxide and N, N, 4-trimethylaniline. N, N, 4-trimethylaniline is used to lower the decomposition temperature of peroxide. This is because the compositions cure at room temperature. Curing by double bonds in the presence of a crosslinking agent proceeds together with curing by the urethane formation mechanism involving terminal hydroxyl groups. Such a combined curing system while extending the chains along urethane bonds and forming cross bonds with an acrylate-containing agent increases the crosslinking density of the elastomer, which increases its strength properties.

Used low molecular weight hydroxyl-containing polybutadiene rubber is similar to the rubber used in the prototype, NISSO PB G-3000 with a hydroxyl content of 0.9-1.2%, a molecular weight of 2600-3200. Also used are the hydroxyl-containing polybutadiene rubber Krasol LBH 3000 with a hydroxyl content of 0.9-1.2%, a molecular weight of 2800-3200, a rubber copolymer of isoprene and butadiene PDI-1K with a monomer ratio of 20:80, with an average molecular weight of 3000 -3500 and the content of hydroxyl groups 0.7-1.1% (TU 38.103342-88).

As a plasticizer, the composition contains products commonly used in the manufacture of elastomeric materials based on diene rubbers: oils of petroleum origin, for example, netoxol oil or PM oil, chloroparaffins, alkyl (aryl) phthalic acid esters.

Fillers of the composition are mineral powders, such as chalk, calcium oxide, lime screenings, marshalite, granular rubber.

Polyisocyanates, in particular polymethylene phenyl isocyanates based on 4,4′-diphenylmethanediisocyanate (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%.

Methyl methacrylate (GOST 20370-74), butyl methacrylate (TU 2435-025-55856863-2004), triethylene glycol dimethacrylate (TU 6-01-843-73) and MGF-9 oligoester acrylate (TU 2226-002-99176106) are used as the crosslinking agent. -2012).

Benzoyl peroxide (TU 2417-006-51764779-2007), ditretbutyl peroxide (TU 6-05-2026-86) and lauryl peroxide (TU 6-05-1998-85) are used as the peroxide initiator.

For the manufacture of the coating composition, mixing equipment is used to ensure uniform distribution of the plasticizer, filler, polyisocyanate, crosslinking agent, peroxide initiator and activator in the rubber, with further obtaining a homogeneous mixture.

The invention is illustrated by the following examples.

Example 1. In a mixer with an anchor mixer of 1 liter volume, 100 g of rubber, 190 g of chalk, 10 g of calcium oxide, 90 g of chloroparaffin XP-470, 5 g of crosslinking agent are loaded. The mixture is stirred for 5-10 minutes. Then add 12 g of polyisocyanate, 0.05 g of peroxide initiator and 0.01 g of N, N, 4-trimethylaniline. After that, the mixture is stirred for 1-2 minutes, applied by pouring onto flat forms and incubated at 20-30 ° C for 3-5 days.

Similarly prepare compositions of composition 2-14.

The composition and properties of all studied compositions are shown in the table.

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

As the crosslinking agent content increases, the hardness and strength of the cured products increase. Starting at 5 parts by weight the crosslinking agent increases the hardness, with large quantities increases both the hardness and strength of the resulting products up to 100 parts by weight With a further increase in the crosslinking agent, an increase in strength indicators is not observed, which is associated with an excess of the crosslinking agent and the corresponding delamination of the system. When the content of acrylate-containing crosslinking agent is less than 5 parts by weight an increase in hardness and strength is not observed.

With an increase in the content of peroxide initiator, an increase in strength indicators is also observed, while the optimal amount of peroxide is 0.05-5 wt.h. (1-5% of crosslinking agent). A further increase in peroxide initiator does not lead to an increase in strength indicators. The nature of the initiator does not affect the properties of the resulting products.

When the content of polyisocyanate is less than 8 parts by weight the level of the complex of strength properties decreases due to a significant deviation of the NCO: OH ratio from stoichiometric and a decrease in the crosslink density. With large quantities of polyisocyanate more than 20 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.

The increase in the amount of filler over 300 parts by weight creates difficulties in the formation of a monolithic homogeneous structure of the samples due to the high viscosity.

The high content of plasticizer (over 130 parts by weight) leads to sweating out of the coating due to exceeding the compatibility limits with rubber.

Thus, the advantage of elastomers for coatings based on the proposed composition is a higher hardness and strength.

Claims (1)

A coating composition comprising a low molecular weight hydroxyl-containing rubber based on butadiene, a plasticizer, a filler, an isocyanate hardener - polyisocyanate, characterized in that the rubber contains hydroxyl-containing polybutadiene rubber or a rubber-copolymer of isoprene and butadiene, and additionally, acrylate contains acrylate and methyl acrylate , butyl methacrylate, triethylene glycol dimethacrylic ester and MGF-9 oligoester acrylate, peroxide initiator and N, N, 4-trimethylaniline in the wake schiem component ratio, mass parts .:
The specified hydroxyl-containing polybutadiene rubber one hundred Plasticizer 40-130 Filler 50-300 Isocyanate Hardener - Polyisocyanate 8-20 Acrylate Crosslinking Agent 5-100 Peroxide initiator 0.05-5 N, N, 4-trimethylaniline 0.01-0.1