Polyurethane coating for road marking and preparation method thereof

Abstract

The invention relates to a polyurethane coating for road marking, which is characterized in that the polyurethane coating is constructed on a road surface by using different construction modes, and then glass beads are scattered to play a role in guiding and controlling traffic. The material has the advantages of being wide in substrate selectable range, adjustable in opening time, high in strength, good in toughness, excellent in freeze thawing resistance, low in energy consumption, good in pollution resistance, odorless, healthy for human bodies, environment-friendly and the like.

Description

Technical Field

[0001] The invention relates to the field of road markings, and in particular to a two-component polyurethane coating for road markings and a preparation method thereof. Background Art

[0002] Road markings are a kind of safety sign. Traffic management departments use them to guide and instruct traffic, thereby improving traffic safety, reducing traffic accidents, and further improving road transportation capacity.

[0003] In the field of road marking, the main materials commonly used at present are hot-melt coatings and two-component MMA coatings. Among them, hot-melt coatings are solid at room temperature and need to be heated for construction. The operation is dangerous and energy-consuming. At the same time, they are brittle, poor in low-temperature resistance, easy to be damaged, and have a very short service life. Although two-component MMA coatings have a longer service life than hot-melt coatings, they have the disadvantages of long opening time in winter, poor health for human body, poor environmental friendliness, and high flammability and hazard of curing agents. The polyurethane road marking coatings currently used are mainly water-based polyurethane coatings and hydroxyl acrylate polyurethane coatings. Both still have major shortcomings. For example, the former cannot prepare structural markings and has a long opening time in winter. The latter still has a large amount of volatile substances such as solvents in the system, which cause great harm to the human body and the environment, limiting the application of polyurethane road marking coatings in the field of road marking coatings.

[0004] Since polyurethane has excellent mechanical properties, optical properties and service life, it has been initially applied in the field of road marking. Among them, the patents CN116948516A and CN113372806A use polyurethane modified acrylate materials to improve the toughness and strength of the materials, but their main body is still acrylate material, and their toughness, mechanical strength and safety are still poor; the patent CN114525073A uses hydroxy acrylate and HDI biuret to prepare two-component polyurethane road markings. Although it can obtain good mechanical properties and service life, the hydroxy acrylate contains a large amount of volatile organic solvents (such as toluene, etc.), which is not conducive to the molding of thicker markings, and at the same time, it has great harm to the human body and the environment; the patent CN116102970A uses water-based polyurethane acrylate to prepare road markings by light curing, but it is a water-based material, and it is difficult to prepare a structural marking with a certain thickness, which limits its practical application. At the same time, it contains a large amount of acrylate monomers, which are harmful to the environment and the human body.

[0005] Therefore, it is very necessary to obtain a polyurethane material for road marking that has a wide range of optional substrates, a wide range of construction thicknesses, no effect on the open time, arbitrarily adjustable open time, high strength, good toughness, excellent freeze-thaw resistance, low energy consumption, good stain resistance, no odor, human health and environmental friendliness. Summary of the invention

[0006] The present invention provides a polyurethane material for road marking paint and a preparation method thereof. The material is applied to road markings and has the advantages of a wide range of substrate options, adjustable open time, high strength, good toughness, superior freeze-thaw resistance, low energy consumption, good anti-fouling, no odor, and is friendly to human health and the environment. At the same time, the bio-based material complies with national laws and regulations.

[0007] To achieve the above object, the technical solution adopted by the present invention is:

[0008] A polyurethane coating for road markings, comprising component A and component B, wherein the mass ratio of component A to component B is 100:4-18, preferably 100:7-14;

[0009] The component A comprises the following raw materials in parts by weight:

[0010]

[0011]

[0012] In the present invention, the component B is selected from one or more of aliphatic isocyanate, alicyclic isocyanate and derivatives thereof having an NCO functionality of ≥2.

[0013] In the present invention, the modified vegetable oil polyol is a vegetable oil polyol including an aromatic ring, an alicyclic ring and / or a heterocyclic ring in the molecular chain, and the hydroxyl value is 120-20 mgKOH / g.

[0014] In the present invention, the monomers for preparing the modified vegetable oil polyol include vegetable oil polyol and cyclic monocarboxylic acid. The vegetable oil polyol and the cyclic monocarboxylic acid are reacted to prepare the modified vegetable oil polyol, the mass ratio of the vegetable oil polyol to the cyclic monocarboxylic acid is 100:0.1-10.0, the reaction temperature of the vegetable oil polyol and the cyclic monocarboxylic acid is 60-250°C, and the reaction time is 1-24h.

[0015] In the present invention, the vegetable oil polyol is selected from vegetable oil polyols with a hydroxyl functionality of ≥3, preferably one or more of castor oil, lesquerella oil, soybean oil polyol, sunflower oil polyol, palm oil polyol, linseed oil polyol, rapeseed oil polyol, tung oil polyol, cashew oil polyol, and neem oil polyol, and the hydroxyl value is 150-250 mgKOH / g, and castor oil and / or soybean oil polyol is more preferred.

[0016] In the present invention, the ring-containing monocarboxylic acid is a monocarboxylic acid containing an aromatic ring, an aliphatic ring and / or a heterocyclic ring, and has a molecular weight of 50-300 g / mol. It is preferably a carboxylic acid containing the following structure, wherein the carboxyl group may be directly connected to the ring or connected to the ring in the form of HOOC-(CH2)-, etc., and n=1-30:

[0017]

[0018] In the present invention, the water reducer is one or more of a chemical water reducer and / or a physical water reducer. Preferably, the chemical water reducer is one or more of p-toluenesulfonyl isocyanate, triethyl orthoformate, and oxazolidine water reducers, and / or the physical water reducer is one or more of anhydrous calcium chloride, barium oxide, calcium oxide, magnesium sulfate, calcium sulfate, calcium hydride, and molecular sieve activation powder, more preferably molecular sieve activation powder.

[0019] In the present invention, the catalyst is one or more of a Lewis acidic organic metal catalyst and an organic amine catalyst. Preferably, the organic amine catalyst is selected from triethylenediamine, bis(dimethylaminoethyl) ether, bis(dimethylaminoethyl) glycol ether, dimethylcyclohexylamine, N-methyldicyclohexylamine, pentamethyldiethyltriamine, pentamethyldipropylenetriamine, tetramethylethylenediamine, tetramethylpropylenediamine, tetramethylhexanediamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine, tris(dimethylaminopropyl)amine, N,N-dimethyl Benzylamine, N,N-dimethyl (hexadecyl) amine, dimethylethanolamine, dimethylaminoethoxyethanol, trimethylhydroxyethylethylenediamine, trimethylhydroxyethylpropylenediamine, N,N-bis (dimethylaminopropyl) isopropanolamine, N,N,N'-trimethyl-N'-hydroxyethyl bisaminoethyl ether, N-(dimethylaminopropyl) diisopropanolamine, tetramethyldipropylenetriamine, bis (dimethylamino)-2-propanol, diethylethanolamine, N,N',N'-tris (2-hydroxypropyl) ethylenediamine, 1,4-dimethylpiperazine, 1-dimethylaminoethyl-4-methylpiperazine, N-methyl-N'-hydroxyethyl 1-(4-morpholinyl)-2-propylamine, N-methylpiperazine, N,N-dimethyl(4-methyl-1-piperazinyl)ethylamine, N-methylmorpholine, N-ethylmorpholine, bismorpholinyl diethyl ether, N-cocomorpholine, dimorpholine triethyl ether, N-(dimethylaminoethyl)morpholine, 4-(2-methoxyethyl)morpholine, dimorpholine polyoxyethylene ether, 4-butylmorpholine, 1-(4-morpholinyl)-2-propylamine, N-methylimidazole, 1,2-dimethylimidazole, N-2-(hydroxypropyl)imidazole, N-2-(hydroxyethyl)imidazole, N-2-(aminopropyl)imidazole, 1,8-diazacycloundecene, triethylamine or Multiple; and / or, the organometallic catalyst is selected from one or more of organic tin compounds, organic potassium compounds, organic lead compounds, organic bismuth compounds, organic mercury compounds, and titanates, more preferably dibutyltin dilaurate, stannous octoate, dibutyltin di(dodecylsulfide), dibutyltin diacetate, dioctyltin dilaurate, dialkyltin dimaleate, dialkyltin dithiol, potassium isooctanoate, potassium acetate, potassium oleate, lead isooctanoate, phenylmercuric acetate, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, bismuth cyclohexaneate, bismuth laurate, tetrabutyl titanate, and one or more of tetraisopropyl titanate.

[0020] In the present invention, the color filler is selected from inorganic and / or organic powders with a particle size of 1nm-2mm. Preferably, the inorganic powder is one or more of glass beads, calcium carbonate, talc, quartz powder, mineral powder, titanium dioxide, aluminum hydroxide, molecular sieve activated powder, bentonite, glass fiber, kaolin, silicon powder, and fumed silica, and / or the organic powder is one and / or more of plastic powder, rubber powder, organic starch, cellulose, and chitosan, preferably calcium carbonate, titanium dioxide, and glass beads.

[0021] In the present invention, the component B belongs to the curing agent component, which is one or more of HDI, HDI dimer, HDI trimer, HDI biuret, IPDI, IPDI trimer, HMDI, NDI, PPDI, CHDI, XDI, HXDI, TMHDI, NBDI, TODI, and HTDI.

[0022] The present invention also provides a method for preparing the polyurethane coating for road markings, comprising the following steps:

[0023] S1: Mixing modified vegetable oil polyol, water reducing agent, catalyst, pigment and filler to obtain component A;

[0024] S2: After mechanically mixing component A and curing agent component B, apply them on the substrate by scraping, extrusion, spin coating or spraying. The total amount of component A and component B is 1-8kg / m 2 , preferably 2-6kg / m 2 .

[0025] Preferably, in S2, the substrate is inorganic cementitious material concrete and / or organic binder concrete, more preferably gypsum concrete, cement concrete, asphalt concrete and / or resin concrete.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) Solvent-free coatings and bio-based materials are friendly to human health and the environment.

[0028] (2) The construction temperature range is wide, and the opening time can be adjusted at any time by adjusting the catalyst to solve the problem of long opening time in winter.

[0029] (3) The use of modified vegetable oil polyols has outstanding weather resistance, water resistance, and freeze-thaw resistance. At the same time, the material's hydrophobicity and anti-fouling properties are enhanced, greatly increasing the material's service life.

[0030] (4) Modified vegetable oil polyols introduce a rigid ring into the molecular chain, which has strong resistance to deformation and wear. At the same time, it has strong shear resistance, compression resistance and bonding strength. At the same time, combined with the vegetable oil molecular chain, the material has the characteristics of high strength and high toughness, and still presents the same performance in winter, which is suitable for different regional environments.

[0031] (5) The material contains both non-polar and polar segments and can be applied to pavement materials of different textures.

[0032] (6) Use two-component polyurethane road marking paint, which has higher whiteness and brightness than the current two-component MMA paint. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with relevant embodiments. The embodiments are only used as illustrations of the present invention and do not limit the scope of the present invention.

[0034] The main raw materials used in the examples of the present invention are as follows, and the others are common commercially available raw materials unless otherwise specified:

[0035] Vegetable oil polyols: castor oil, hydroxyl value 163 mgKOH / g; soybean oil polyol, brand HM-13200, purchased from Haierma, hydroxyl value 200±20 mgKOH / g; cashew nut shell oil polyol, purchased from Guangzhou Haoyi New Materials Technology Co., Ltd., brand FX-9001LV, hydroxyl value 175 mgKOH / g.

[0036] Modified vegetable oil polyols: Polyols-1, Polyols-2, Polyols-3, Polyols-4, Polyols-5, Polyols-6, Polyols-7, Polyols-8 are homemade.

[0037] Water reducing agent: molecular sieve activated powder, purchased from Shanghai Yilan.

[0038] Catalyst: Potassium 2-ethylhexanoate K-15, Zinc neodecanoate ZN-1910.

[0039] Two-component MMA coating: scraping type, purchased from Zhejiang Brothers Road Signs.

[0040] Isocyanate: IPP-270, HT-100, purchased from Wanhua Chemical.

[0041] Modified vegetable oil polyol-1

[0042] In the esterification reaction, castor oil and benzoic acid were mixed in a mass ratio of 100:1 and then heated to 235°C for reaction for 1 hour to prepare Polyols-1 with a hydroxyl value of 160±20 mgKOH / g.

[0043] Modified vegetable oil polyol-2

[0044] In the esterification reaction, castor oil and cyclopentanoic acid were mixed in a mass ratio of 100:1 and then heated to 60°C for reaction for 24 hours to prepare Polyols-2 with a hydroxyl value of 155±20 mgKOH / g.

[0045] Modified vegetable oil polyol-3

[0046] In the esterification reaction, soybean oil polyol and phenylacetic acid were mixed in a mass ratio of 100:2 and reacted at 235° C. for 1 h to prepare Polyols-3 with a hydroxyl value of 190±20 mgKOH / g.

[0047] Modified vegetable oil polyol-4

[0048] In the esterification reaction, cashew nut shell oil polyol and phenylpropionic acid were mixed in a mass ratio of 100:9 and reacted at 235° C. for 1 h to prepare Polyols-4 with a hydroxyl value of 130±20 mgKOH / g.

[0049] Modified vegetable oil polyol-5

[0050] In the esterification reaction, castor oil and 1-naphthoic acid were mixed in a mass ratio of 100:5 and then heated to 235° C. for reaction for 24 h to prepare Polyols-5 with a hydroxyl value of 140±20 mgKOH / g.

[0051] Modified vegetable oil polyol-6

[0052] In the esterification reaction, castor oil and cyclohexanecarboxylic acid were mixed in a mass ratio of 100:4 and then heated to 200°C for reaction for 24 hours to prepare Polyols-6 with a hydroxyl value of 140±20 mgKOH / g.

[0053] Modified vegetable oil polyol-7

[0054] In the esterification reaction, castor oil and epoxy propionic acid were mixed in a mass ratio of 100:2.5, and the mixture was heated to 60°C for 24 hours to prepare Polyols-7 with a hydroxyl value of 140±20 mgKOH / g.

[0055] Modified vegetable oil polyol-8

[0056] In the esterification reaction, castor oil and 4-pyridineacetic acid were mixed in a mass ratio of 100:4 and then heated to 235° C. for reaction for 24 h to prepare Polyol s-8 having a hydroxyl value of 140±20 mgKOH / g.

[0057] The performance testing method used in the embodiment of the present invention is as follows:

[0058] Tensile strength and elongation at break: tested in accordance with GB / T 1040-2018.

[0059] Pull-out strength: tested in accordance with JG / T 24-2018.

[0060] Contact angle: tested in accordance with GB / T 30693-2014.

[0061] Abrasion resistance: Tested according to T0752 in JTG E20-2011.

[0062] Aging resistance: tested in accordance with GB / T 16777-2008.

[0063] Anti-fouling performance: tested in accordance with GB / T 9780-2013.

[0064] Embodiment 1-11

[0065] Two-component polyurethane road marking paint: Prepare according to the raw materials and amounts of the composition in Table 1 below.

[0066] The two-component polyurethane road marking paints of Examples 1-11 were prepared as follows:

[0067] (1) The modified vegetable oil polyol, water reducing agent, catalyst, pigment and filler are mixed by a disperser (1000 RPM×2 min) to obtain component A;

[0068] (2) After mechanically mixing component A and curing agent component B (1000RPM×2min), apply them on the substrate by scraping, with a dosage of 2kg / m 2 The substrate is selected from steel plate, cement concrete and asphalt concrete to obtain the two-component polyurethane road marking paints 1-11 in the examples.

[0069] Table 1 Type and amount of raw materials used in the examples (g)

[0070]

[0071]

[0072] Comparative Example

[0073] The comparative example directly used the same amount of two-component MMA coating to prepare the test pieces.

[0074] The various embodiments and comparative examples were subjected to tests related to odor, tensile strength and elongation, pull-out strength, strength and elongation after aging, contact angle, etc. The results are shown in Table 2.

[0075] Table 2 Adhesive performance test data

[0076]

[0077] From the adhesive test data in Table 2, it can be concluded that the use of modified vegetable oil polyols in two-component polyurethane road marking paints has the advantages of a wide range of substrate options, adjustable open time, high strength, good toughness, excellent freeze-thaw resistance, low energy consumption, good stain resistance, no odor, human health and environmental friendliness, etc., which can meet the use requirements in the field of road marking.

[0078] The above is only a preferred embodiment of the present invention. It should be pointed out that other improvements or supplements made by technicians in this field without departing from the present invention should all be within the protection scope of the present invention.

Claims

1. A polyurethane coating for road marking, characterized in that: Comprising component A and component B, wherein the mass ratio of component A to component B is 100:4-18, preferably 100:7-14; The component A comprises the following raw materials in parts by weight: The component B is selected from one or more of aliphatic isocyanates, alicyclic isocyanates and derivatives thereof having an NCO functionality of ≥2.

2. The polyurethane coating according to claim 1, characterized in that: The modified vegetable oil polyol is a vegetable oil polyol including an aromatic ring, an alicyclic ring and / or a heterocyclic ring in the molecular chain, and the hydroxyl value is 120-240 mgKOH / g.

3. The polyurethane coating according to claim 1 or 2, characterized in that: The monomers for preparing the modified vegetable oil polyol include vegetable oil polyol and ring-containing monocarboxylic acid; preferably, the vegetable oil polyol is selected from vegetable oil polyols with a hydroxyl functionality ≥ 3, preferably one or more of castor oil, lesquerella oil, soybean oil polyol, sunflower oil polyol, palm oil polyol, linseed oil polyol, rapeseed oil polyol, tung oil polyol, cashew oil polyol and neem oil polyol, with a hydroxyl value of 150-250 mgKOH / g, more preferably castor oil and / or soybean oil polyol.

4. The polyurethane coating according to claim 3, characterized in that: The ring-containing monocarboxylic acid is a monocarboxylic acid containing an aromatic ring, an alicyclic ring and / or a heterocyclic ring, and has a molecular weight of 50-300 g / mol, preferably a carboxylic acid containing the following structure:

5. The polyurethane coating according to claim 3 or 4, characterized in that: The mass ratio of the vegetable oil polyol to the cyclic monocarboxylic acid is 100:0.1-10.0, the reaction temperature of the vegetable oil polyol and the cyclic monocarboxylic acid is 60-250° C., and the reaction time is 1-24 hours.

6. The polyurethane coating according to any one of claims 1 to 5, characterized in that: The water reducer is one or more of a chemical water reducer and / or a physical water reducer. Preferably, the chemical water reducer is one or more of p-toluenesulfonyl isocyanate, triethyl orthoformate, and oxazolidine water reducers, and / or the physical water reducer is one or more of anhydrous calcium chloride, barium oxide, calcium oxide, magnesium sulfate, calcium sulfate, calcium hydride, and molecular sieve activation powder, more preferably molecular sieve activation powder.

7. The polyurethane coating according to any one of claims 1 to 6, characterized in that: The catalyst is one or more of a Lewis acidic organic metal catalyst and an organic amine catalyst. Preferably, the organic amine catalyst is selected from triethylenediamine, bis(dimethylaminoethyl) ether, bis(dimethylaminoethyl) glycol ether, dimethylcyclohexylamine, N-methyldicyclohexylamine, pentamethyldiethyltriamine, pentamethyldipropylenetriamine, tetramethylethylenediamine, tetramethylpropylenediamine, tetramethylhexanediamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine, tris(dimethylaminopropyl)amine, N,N-dimethylbenzylamine, N,N-dimethyl (hexadecyl) amine, dimethylethanolamine, dimethylaminoethoxyethanol, trimethylhydroxyethylethylenediamine, trimethylhydroxyethylpropylenediamine, N,N-bis (dimethylaminopropyl) isopropanolamine, N,N,N'-trimethyl-N'-hydroxyethyl bisaminoethyl ether, N-(dimethylaminopropyl) diisopropanolamine, tetramethyldipropylenetriamine, bis (dimethylamino)-2-propanol, diethylethanolamine, N,N',N'-tris (2-hydroxypropyl) ethylenediamine, 1,4-dimethylpiperazine, 1-dimethylaminoethyl-4-methylpiperazine, N-methyl-N'-hydroxyethylpiperazine Oxazine, N,N-dimethyl (4-methyl-1-piperazinyl) ethylamine, N-methylmorpholine, N-ethylmorpholine, bismorpholinyl diethyl ether, N-cocomorpholine, dimorpholine triethyl ether, N-(dimethylaminoethyl)morpholine, 4-(2-methoxyethyl)morpholine, dimorpholine polyoxyethylene ether, 4-butylmorpholine, 1-(4-morpholinyl)-2-propylamine, N-methylimidazole, 1,2-dimethylimidazole, N-2-(hydroxypropyl)imidazole, N-2-(hydroxyethyl)imidazole, N-2-(aminopropyl)imidazole, 1,8-diazacycloundecene, triethylamine, one or more thereof species; and / or, the organometallic catalyst is selected from one or more of an organotin compound, an organopotassium compound, an organolead compound, an organobismuth compound, an organomercury compound, and a titanate, more preferably dibutyltin dilaurate, stannous octoate, dibutyltin di(dodecylsulfide), dibutyltin diacetate, dioctyltin dilaurate, dialkyltin dimaleate, dialkyltin dithiol, potassium isooctanoate, potassium acetate, potassium oleate, lead isooctanoate, phenylmercuric acetate, zinc isooctanoate, bismuth isooctanoate, bismuth neodecanoate, bismuth cyclohexaneate, bismuth laurate, tetrabutyl titanate, and one or more of tetraisopropyl titanate.

8. The polyurethane coating according to any one of claims 1 to 7, characterized in that: The pigment filler is selected from inorganic and / or organic powders with a particle size of 1nm-2mm. Preferably, the inorganic powder is one or more of glass beads, calcium carbonate, talc, quartz powder, mineral powder, titanium dioxide, aluminum hydroxide, molecular sieve activated powder, bentonite, glass fiber, kaolin, silicon powder, and fumed silica, and / or the organic powder is one or more of plastic powder, rubber powder, organic starch, cellulose, and chitin.

9. The polyurethane coating according to any one of claims 1 to 8, characterized in that: The component B is one or more of HDI, HDI dimer, HDI trimer, HDI biuret, IPDI, IPDI trimer, HMDI, NDI, PPDI, CHDI, XDI, HXDI, TMHDI, NBDI, TODI, and HTDI.

10. The method for preparing the polyurethane coating according to any one of claims 1 to 9, characterized in that: The following steps are involved: (1) mixing modified vegetable oil polyol, water reducing agent, catalyst, pigment and filler to obtain component A; (2) After mechanically mixing component A and component B, apply them on the substrate by scraping, extrusion, spin coating or spraying. The total amount of component A and component B is 1-8 kg / m 2 , preferably 2-6kg / m 2 ; Preferably, in step (2), the substrate is inorganic cementitious material concrete and / or organic binder concrete, more preferably gypsum concrete, cement concrete, asphalt concrete and / or resin concrete.

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