Polyurea composition

Abstract

The present invention relates to a polyurea composition having excellent workability, strength, and adhesion.

Description

Technology Field

[0001] The present invention relates to a polyurea composition having excellent workability, strength, and adhesion. Background Technology

[0002] Interior and exterior surfaces of buildings, such as floors and walls, are composed of various materials including concrete, wood, brick, steel, marble, terrazzo, ceramics, metal plates, and synthetic resins, and various coatings are formed on the exterior surfaces to protect them from physical wear, scratches, stains, and chemical damage. Water-based epoxy coatings and urethane coatings have generally been used as coatings for surface protection.

[0003] For example, Korean published patent 10-2016-0144172 discloses an epoxy paint composition comprising a main component including a liquid bisphenol A type epoxy resin, a reactive diluent, a non-reactive diluent, a plasticizer, a dispersant, a UV stabilizer, an antifoaming agent, and an antisettling agent, and a curing agent. However, in the case of epoxy coatings, there is a problem that yellowing occurs or long-term weather resistance is poor due to low elongation. On the other hand, in the case of urethane coatings, although elongation is excellent, there is a problem that periodic maintenance is required because tensile strength and weather resistance are poor.

[0004] Polyurea coatings have been proposed to solve these problems, but conventional polyurea compositions have a pot life of less than 30 minutes, making them difficult to use in workplaces where painting is done using rollers or brushes, and particularly in the summer, the pot life is very short, making painting work difficult. In addition, there is a problem of yellowing occurring due to chemical structural defects.

[0005] Accordingly, there is a need to develop a polyurea composition that offers excellent workability due to its long pot life, while also possessing superior film properties such as strength and adhesion. The problem to be solved

[0006] The present invention provides a polyurea composition that has excellent workability due to its long pot life, while also having excellent film properties such as strength and adhesion. means of solving the problem

[0007] The present invention provides a polyurea composition comprising: a main component comprising an aspartic ester and an aldimin; and a curing agent component comprising a polyisocyanate in which a monofunctional alcohol and a monofunctional amine silane are added to the terminal isocyanate groups of the polyisocyanate. Effects of the invention

[0008] The present invention provides a polyurea composition with excellent workability, strength, and adhesion. The polyurea composition according to the present invention offers excellent workability due to its long pot life, while simultaneously providing excellent film properties such as strength and adhesion. Specific details for implementing the invention

[0009] The present invention will be described in detail below. However, it is not limited to the following description, and each component may be modified in various ways or selectively combined as needed. Accordingly, it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0010] The "weight-average molecular weight" as used in this specification is measured by conventional methods known in the art, for example, by the gel permeation chromatography (GPC) method. Functional groups such as "hydroxyl groups" are measured by conventional methods known in the art, for example, by the titration method.

[0011] The polyurea composition of the present invention comprises a main component comprising an aspartic ester and an aldimin; and a curing agent component comprising a polyisocyanate in which a monofunctional alcohol and a monofunctional amine silane are added to the terminal isocyanate groups of the polyisocyanate.

[0013] <Main Section>

[0014] Aspartic ester

[0015] The main component of the polyurea composition of the present invention comprises an aspartic ester. As the aspartic ester, any conventional aspartic ester used in the relevant technical field may be used without special limitations. Non-limiting examples of usable aspartic esters include commercially available Covestro desmopen NH-1420, desmopen NH-1520, and desmopen NH-2850, which may be used alone or in a mixture of two or more types.

[0016] Aspartic esters are classified into fast-drying, standard, slow-drying, and ultra-slow-drying aspartic esters based on their reaction rate. The reaction rate of aspartic esters is evaluated by measuring the time until curing is completed by mixing aspartic ester and isocyanate (HDI Trimer) in an equivalent ratio of 1:1 at room temperature (25 ℃). If the curing completion time is less than 15 minutes, it is classified as fast-drying aspartic ester; if it is 20 to 40 minutes, as standard aspartic ester; if it is 60 to 100 minutes, as slow-drying aspartic ester; and if it is 160 to 200 minutes, as ultra-slow-drying aspartic ester.

[0017] In the present invention, the aspartic ester comprises a first aspartic ester and a second aspartic ester.

[0018] Aspartic esters can be prepared by the reaction of amines such as para-diaminodicyclohexylmethane (PACM), 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane (DMDC), and polyethyl amine (Jeffamine D230) with maleates such as dibutyl maleate (DBM) and diethyl maleate (DEM).

[0019] The first aspartic ester is a standard aspartic ester and can provide excellent strength to the coating composition due to its alicyclic structure. The first aspartic ester can be prepared by the reaction of an alicyclic amine and a maleate. For example, the first aspartic ester may be tetraethyl N,N'-(methylenedi-4,1-cyclohexanediyl)bis(aspartate) prepared by reacting para-diaminodicyclohexylmethane (PACM) with dibutyl maleate (DBM).

[0020] The weight-average molecular weight of the first aspartic ester may be 300 to 1,000 g / mol, for example, 400 to 550 g / mol. If the weight-average molecular weight is below the aforementioned range, the steric hindrance effect may be reduced and the reaction may be accelerated, and if it exceeds the aforementioned range, the steric hindrance effect may be increased and the curing may be very slow.

[0021] The amine equivalent of the first aspartic ester may be 100 to 500 g / eq, for example, 250 to 350 g / eq. If the amine equivalent is less than the aforementioned range, curing may not proceed completely because there is a lack of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent, and if it exceeds the aforementioned range, the appearance of the coating film may be poor because there is an excess of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent.

[0022] The amine value of the first aspartic ester may be 50 to 350 mgKOH / g, for example, 150 to 250 mgKOH / g. If the amine value is below the aforementioned range, curing may not proceed completely due to a lack of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent, and if it exceeds the aforementioned range, the appearance of the coating film may be poor because there is an excess of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent.

[0023] The polyurea composition of the present invention may contain 50 to 80 weight%, for example 60 to 70 weight%, of the first aspartic ester based on the total weight of the main component. If the content of the first aspartic ester is less than the aforementioned range, the reactivity may be slowed down and curing may be delayed, and if it exceeds the aforementioned range, the working time may be shortened due to the rapid reactivity.

[0024] The second aspartic ester is a paper-dried aspartic ester and has a cycloaliphatic structure containing an alkyl group. The second aspartic ester can be prepared by the reaction of a cycloaliphatic amine containing an alkyl group and a maleate. For example, the second aspartic ester can be prepared by the reaction of 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane (DMDC) and diethyl maleate (DEM).

[0025] The weight-average molecular weight of the second aspartic ester may be 300 to 1,000 g / mol, for example, 350 to 550 g / mol. If the weight-average molecular weight is below the aforementioned range, curing may not proceed completely because there is a lack of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent, and if it exceeds the aforementioned range, the appearance of the coating film may be poor because there is an excess of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent.

[0026] The amine equivalent of the second aspartic ester may be 100 to 500 g / eq, for example, 250 to 350 g / eq. If the amine equivalent is less than the aforementioned range, curing may not proceed completely because there is a lack of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent, and if it exceeds the aforementioned range, the appearance of the coating film may be poor because there is an excess of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent.

[0027] The amine value of the second aspartic ester may be 50 to 350 mgKOH / g, for example, 150 to 250 mgKOH / g. If the amine value is below the aforementioned range, curing may not proceed completely because there is a lack of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent, and if it exceeds the aforementioned range, the appearance of the coating film may be poor because there is an excess of NCO reactive groups in the curing agent during the reaction between the main component and the curing agent.

[0028] The polyurea composition of the present invention may contain 10 to 40 weight%, for example 15 to 30 weight%, of the second aspartic ester based on the total weight of the main component. If the content of the second aspartic ester is less than the aforementioned range, the effect on the reaction is insufficient, so the pot life may be shortened, and if it exceeds the aforementioned range, the curing may be delayed because the reaction time is slowed down.

[0029] The first aspartic ester and the second aspartic ester may be used in a weight ratio of 2.33 to 4:1. By using the two types of aspartic esters in the aforementioned mixing ratio, a coating composition with excellent weather resistance and capable of curing at room temperature can be provided. If the mixing ratio of the first aspartic ester to the second aspartic ester is less than the aforementioned range, solidification drying may be slowed down, and if it exceeds the aforementioned range, the working time may be shortened.

[0030] The polyurea composition of the present invention may contain 60 to 90 weight%, for example 70 to 85 weight%, of the aspartic ester based on the total weight of the main component. If the content of the aspartic ester is less than the aforementioned range, the curability may be reduced and the physical properties of the coating film may be degraded, and if it exceeds the aforementioned range, the pot life may be shortened and workability may be inferior.

[0032] Aldimin

[0033] The main component of the polyurea composition of the present invention comprises aldimin. Aldimin, which is a latent amine, acts as a chain extender and increases the bonding degree between each component in the polyurea composition, thereby improving physical properties such as wear resistance and hardness, and also improves workability by providing a sufficient pot life.

[0034] Aldimin can be prepared by the condensation reaction of an amine and an aldehyde. The amine may be an aliphatic or aromatic primary amine. Primary amines act as functional groups during the curing reaction; however, since amine groups are capped within the aldimin condensed with the aldehyde, the reaction with the isocyanate in the curing agent does not occur rapidly when in the paint state. On the other hand, during film formation, the aldimin reacts with moisture in the atmosphere to generate primary amines again, which then react with the isocyanate in the curing agent. Therefore, by using aldimin, it is possible to secure a sufficient pot life while simultaneously achieving excellent film properties.

[0035] Non-limiting examples of the above amines include isophorone diamine, diethylene diamine, methane diamine, ethyl diamine, propylene diamine, 1,2-bis-(2-amino-phenyldioethane), dimethyltoluene diamine (DMTDA), diethyltoluene diamine (DETDA), dimethylthiotoluene diamine, 1,3-trimethylene glycol-bis(para-aminobenzoate), methylene-bis-N,N'-dibutylaniline, polyoxypropylene diamine, metaxylene diamine, etc. These may be used alone or in a mixture of two or more.

[0036] Non-limiting examples of the above aldehydes include benzaldehyde, acetaldehyde, propionaldehyde, butylaldehyde, isobutylaldehyde, etc. These may be used alone or in a mixture of two or more.

[0037] The weight-average molecular weight of the above aldimin may be 100 to 400 g / mol, for example, 150 to 250 g / mol. If the weight-average molecular weight of the above aldimin is below the aforementioned range, workability may be reduced and swelling may occur because the reactivity increases, and if it exceeds the aforementioned range, the mechanical properties of the coating film may be reduced because the reactivity decreases.

[0038] The amine equivalent of the above aldimin may be 50 to 250 g / eq, for example, 100 to 130 g / eq. If the amine equivalent of the above aldimin is less than the aforementioned range, the mechanical properties of the coating film may be reduced because the reactivity is lowered, and if it exceeds the aforementioned range, workability may be reduced because the reactivity is higher.

[0039] The polyurea composition of the present invention may contain 0.1 to 10 weight%, for example, 3 to 7 weight% of the aldimin based on the total weight of the main component. If the content of aldimin is less than the aforementioned range, mechanical properties such as tensile strength, tear strength, elongation, and hardness may be reduced, and if it exceeds the aforementioned range, a film may form on the surface of the coating film, resulting in inferior appearance characteristics.

[0041] solvent

[0042] The main component of the polyurea composition of the present invention may include a solvent. Water or any conventional organic solvent known in the art may be used as the solvent without limitation. For example, hydrocarbon solvents, ester solvents, ether solvents, acetate solvents, etc. may be used. These may be used alone or in a mixture of two.

[0043] The content of the above solvent may be the remainder satisfying 100 weight% of the main component, for example, 0.1 to 35 weight% based on the total weight of the main component. When the content of the above solvent falls within the aforementioned range, workability is improved and a coating film with excellent physical properties can be formed.

[0045] additives

[0046] The main component of the polyurea composition of the present invention may include additives known in the art to the extent that they do not impair the inherent properties of the composition. Non-limiting examples of usable additives include defoaming agents and plasticizers.

[0047] Plasticizers play a role in controlling the viscosity of the paint composition and imparting flexibility and elasticity. Conventional plasticizers known in the relevant art may be used as the plasticizer. Non-limiting examples of usable plasticizers include dioctyl phthalate (DOP), diisononyl phthalate (DINP), dioctyl adipate (DOA), trioctyl trimellitate (TOTM), dibutyl phthalate (DBP), diisodecyl phthalate (DIDP), dioctyl melate (DOM), diisononyl adipate (DINA), dioctyl terephthalate (DOTP), butyl 2-ethylhexyl terephthalate (BOTP), esol (Eil Industrial Co., Ltd.), etc. These may be used alone or in a mixture of two or more types. In particular, when non-phthalate plasticizers such as dioctyl terephthalate (DOTP) and butyl 2-ethylhexyl terephthalate (BOTP) are used as plasticizers, an environmentally friendly composition can be provided.

[0048] The content of the above additives can be adjusted within a content range known in the relevant technical field, for example, based on the total weight of the main component, each of which may be 0.1 to 10 weight percent.

[0050] Hardener Department

[0051] polyisocyanate

[0052] The curing agent portion of the polyurea composition of the present invention comprises a polyisocyanate. The polyisocyanate is a polyisocyanate in which a monofunctional alcohol and a monofunctional amine silane are added to the terminal isocyanate groups of the polyisocyanate. By using a polyisocyanate of the above structure, the present invention can provide a composition with a long pot life and excellent film properties.

[0053] The polyisocyanate having an isocyanate at the end may be a hexamethylene diisocyanate-based polyisocyanate, for example, 1,6-hexamethylene diisocyanate isocyanurate trimer. As the polyisocyanate having an isocyanate at the end, commercially available hexamethylene diisocyanate-based isocyanurate trimers (Covestro, N3300, N3600, N3900), burette trimers (Covestro, N100, N3200), etc. may be used, but are not limited to these.

[0054] The above monofunctional alcohol may be an alkyl monofunctional alcohol such as ethanol, butanol, isobutanol, isopropyl alcohol, or lauryl alcohol; an ethylene oxide monofunctional alcohol such as polyoxyethylene monomethyl ether, polyoxyethylene monoaryl ether, polyoxyethylene phenyl ether, polyoxyethylene lauryl ether, or polyoxyethylene polyoxypropylene alkyl ether; or an acrylate monofunctional alcohol such as 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, or 2-hydroxypropyl acrylate.

[0055] For example, the monofunctional alcohol may be an ethylene oxa-based monofunctional alcohol. In this case, the double bond contained in the monofunctional alcohol reacts with the amine of the main component to improve the physical properties of the coating film and achieve low viscosity, thereby further improving the appearance.

[0056] The above monofunctional amine silane may be a silane-based monofunctional amine such as gamma-aminopropyltrimethoxysilane, gamma-aminopropyltriethoxysilane, N-beta-aminoethyl-gamma-aminopropyltriethoxysilane, bis-gamma-trimethoxysilylpropylamine, bis-gamma-trimethoxysilylpropylamine, N-ethyl-gamma-aminoisobutyltrimethoxyoxysilane. In this case, coating film properties, such as adhesion to the substrate, can be further improved through a siloxane reaction.

[0057] For example, the mixing ratio of a polyisocyanate having isocyanates at the ends, a monofunctional alcohol, and a monofunctional amine silane may be 100:1 to 15:10 to 40 by weight, for example, 100:5 to 10:20 to 35 by weight. If the mixing ratio of a monofunctional alcohol to a polyisocyanate having isocyanates at the ends is less than the aforementioned range, the pot life may be short and adhesion may be reduced due to a large number of unreacted functional groups in the isocyanate; if it exceeds the aforementioned range, the pot life may be too long due to a small number of functional groups in the isocyanate, which may reduce drying performance. If the mixing ratio of a monofunctional amine silane to a polyisocyanate having isocyanates at the ends is less than the aforementioned range, the pot life may be short and adhesion may be reduced due to a large number of unreacted functional groups in the isocyanate; if it exceeds the aforementioned range, the pot life may be too long due to a small number of functional groups in the isocyanate, which may reduce drying performance.

[0058] The NCO% (solid content) of the polyisocyanate in which a monofunctional alcohol and a monofunctional amine silane are added to the terminal isocyanate groups of the polyisocyanate may be 7 to 15 weight%.

[0060] solvent

[0061] The curing agent portion of the polyurea composition of the present invention may include a solvent. A high-boiling point solvent may be used as the solvent. In this case, the viscosity of the composition can be lowered to further improve appearance and workability.

[0062] The above high-boiling point solvent may include vinylene carbonates such as ethylene carbonate, propylene carbonate, 1,2-butylene carbonate, and 2,3-butylene carbonate; linear or cyclic carbonates such as dimethyl carbonate, diethyl carbonate, dipropyl carbonate, ethylmethyl carbonate, methylpropyl carbonate, and ethylpropyl carbonate; esters obtained by the reaction of a monobasic or polybasic acid having 8 to 18 carbon atoms with a branched alcohol having 18 or fewer carbon atoms; fatty acid esters including esters obtained by the reaction of an unsaturated fatty acid having 14 to 18 carbon atoms with an alcohol having 4 or fewer hydroxyl groups; and phosphates such as trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, trixyrailyl phosphate, cresyl diphenyl phosphate, and octyl diphenyl phosphate.

[0063] The content of the above solvent may be the remainder satisfying 100 weight% of the curing agent part, for example, 0 to 5 weight% based on the total weight of the curing agent part. When the content of the above solvent falls within the aforementioned range, workability is improved and a coating film with excellent physical properties can be formed.

[0065] Polyurea Composition

[0066] The polyurea composition of the present invention comprises the aforementioned main component and curing agent component.

[0067] The polyurea composition according to the present invention can be prepared according to conventional methods known in the art, for example, by mixing the aforementioned main component and curing agent component in an equivalent ratio of NCO functional groups to amine functional groups of 1.1 to 1.7:1. If the ratio of NCO functional groups to amine functional groups deviates from the aforementioned range, unreacted material may remain, which may degrade the physical properties of the coating film.

[0068] The polyurea composition according to the present invention provides excellent workability due to its long pot life, while simultaneously providing excellent film properties such as strength and adhesion. The polyurea composition of the present invention can be applied to the surface of concrete, metal surfaces, bricks, or existing coatings formed from various paints to provide effects such as substrate protection, appearance improvement, and waterproofing.

[0070] The present invention will be explained in more detail through the following examples. However, the following examples are intended only to aid in understanding the present invention, and the scope of the present invention is not limited to these examples in any way.

[0072] [Examples 1-10]

[0073] Polyurea compositions for each experimental example were prepared according to the compositions in Tables 1 and 2 below.

[0075]

[0076]

[0077] 1st Aspartic Ester: Desmopene NH-1420

[0078] Secondary Aspartic Ester: Desmopene NH-1520

[0079] Aldimin: Bestamine A139

[0080] Plasticizer: Dioctyl terephthalate (DOTP)

[0081] Solvent 1: Propylene glycol monomethyl ether acetate (PMA)

[0082] Polyisocyanate: Desmo N3300

[0083] 1. Functional Alcohol: AAE200 (Hannang Chemical)

[0084] Monofunctional aminesilane: A1170 (Momentive)

[0085] Solvent 2: Propylene Carbonate

[0087] [Physical Property Evaluation]

[0088] The physical properties of the polyurea compositions of each experimental example were measured according to the following method, and the results are shown in Tables 3 and 4 below.

[0090] tensile strength

[0091] It was measured according to the test method specified in the KS F 3211 standard for waterproof coating materials for construction.

[0093] Growth rate

[0094] It was measured according to the test method specified in the KS F 3211 standard for waterproof coating materials for construction.

[0096] Viscosity (25 ℃)

[0097] It was measured using a Brookfield viscometer.

[0099] Lyrics time

[0100] At 25 ℃, Brookfield #7, operating at 10 rpm, the time to reach 300,000 cps was measured.

[0102] Adhesion strength

[0103] Measurements were taken according to the test method specified in ASTM D4541.

[0105]

[0106]

[0107] As shown in Tables 3 and 4 above, the polyurea compositions of Experimental Examples 1-7 according to the present invention exhibited excellent physical properties across all measured items. On the other hand, the polyurea compositions of Experimental Example 8, which used a polyisocyanate in which only one type of monofunctional aminesilane was added to the terminal isocyanate group of the polyisocyanate; Experimental Example 9, which used a polyisocyanate in which only one type of monofunctional alcohol was added to the terminal isocyanate group of the polyisocyanate; and Experimental Example 10, which used a polyisocyanate that did not contain aldimine in the main component and in which neither alcohol nor aminesilane was added to the terminal isocyanate group of the polyisocyanate, exhibited generally inferior physical properties compared to Experimental Examples 1-7.

Claims

Claim 1 A polyurea composition comprising: a main component comprising an aspartic ester and an aldimin; and a curing agent component comprising a polyisocyanate in which a monofunctional alcohol and a monofunctional amine silane are added to the terminal isocyanate groups of the polyisocyanate, wherein the mixing ratio of the polyisocyanate having an isocyanate at the terminals, the monofunctional alcohol, and the monofunctional amine silane is 100:1 to 15:10 to 40 by weight. Claim 2 A polyurea composition according to claim 1, wherein the aspartic ester comprises a first aspartic ester and a second aspartic ester, wherein the first aspartic ester is a standard aspartic ester and the second aspartic ester is a paper-dried aspartic ester. Claim 3 A polyurea composition according to claim 1, wherein the weight-average molecular weight of the aldimin is 100 to 400 g / mol and the amine equivalent is 50 to 250 g / eq. Claim 4 A polyurea composition according to claim 1, wherein the polyisocyanate having an isocyanate at the terminal includes a hexamethylene diisocyanate-based polyisocyanate, and the monofunctional alcohol includes one or more selected from the group consisting of alkyl-based monofunctional alcohols, ethylene oxide-based monofunctional alcohols, and acrylate-based monofunctional alcohols. Claim 5 A polyurea composition according to claim 1, wherein the NCO% (solid content) of the polyisocyanate, in which a monofunctional alcohol and a monofunctional amine silane are added to the terminal isocyanate groups of the polyisocyanate, is 7 to 15 weight%. Claim 6 A polyurea composition according to claim 1, comprising 60 to 90 weight% of the aspartic ester and 0.1 to 10 weight% of the aldimin, based on the total weight of the main component. Claim 7 A polyurea composition according to claim 1, wherein the ratio of NCO functional groups to amine functional groups is 1.1 to 1.7:1 equivalent ratio.

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