Two-component high-toughness normal-temperature curing type road marking paint

Abstract

The application discloses a kind of two-component high toughness normal temperature curing type road marking paint, the road marking paint includes mass ratio (75-85):100 of A component and B component;Wherein, according to mass fraction calculation, A component includes: methyl methacrylate prepolymer 40~60 parts, oxazolidine curing agent 5~10 parts, catalyst 1~5 parts, body filler 30~60 parts, pigment 5~20 parts, adhesion promoter 0.3~0.7 parts, defoaming agent 0.5~1.5 parts, dispersing agent 1~2 parts;B component includes: isocyanate prepolymer 20~50 parts, temperature-sensitive capsule 10~20 parts, body filler 30~60 parts, glass microbead 10~30 parts.The road marking paint of the application can be constructed and cured at normal temperature, with high toughness, low temperature rapid curing, strong wet interface bonding and good durability, and the comprehensive performance is superior to existing two-component marking paint.

Description

Technical Field

[0001] This invention relates to the field of road marking paint technology, and in particular to a two-component, high-toughness, room-temperature curing road marking paint. Background Technology

[0002] Road marking paint is an important material for ensuring traffic safety. Among them, two-component room-temperature curing road marking paint is widely used due to its high solids content, good environmental performance, and superior durability. A typical two-component system usually consists of a resin containing active groups (such as epoxy resin, polyurethane, or acrylate) and a curing agent. During construction, they are mixed and undergo a cross-linking reaction to form a coating film. However, existing two-component road marking paints still have significant shortcomings in practical applications: First, the film has poor flexibility after formation, with a high film modulus and low elongation at break, making it difficult to adapt to road surface deformation caused by thermal expansion and contraction, and prone to cracking and peeling after long-term use; second, the drying speed is slow at low temperatures, especially below 5°C, where the cross-linking reaction activity decreases, leading to a longer road surface closure time and seriously affecting traffic opening efficiency; third, the adhesion on damp substrates (such as roads after rain or in high-humidity environments) is insufficient. The presence of moisture can interfere with the effective wetting of the resin and the substrate, and may even cause a side reaction between the curing agent and water, resulting in loss of adhesion between the coating and the road surface. Therefore, developing a road marking paint that combines high toughness, low-temperature rapid curing, and strong adhesion to wet interfaces is of great practical significance. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a two-component, high-toughness, room-temperature curing road marking paint.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A two-component, high-toughness, room-temperature curing road marking paint is provided, wherein the road marking paint comprises component A and component B in a mass ratio of (75-85):100; Component A, calculated by mass fractions, comprises: 40-60 parts of methyl methacrylate prepolymer, 5-10 parts of oxazolidine curing agent, 1-5 parts of catalyst, 30-60 parts of extender filler, 5-20 parts of pigment, 0.3-0.7 parts of adhesion promoter, 0.5-1.5 parts of defoamer, and 1-2 parts of dispersant; Component B includes: 20-50 parts of isocyanate prepolymer, 10-20 parts of thermosensitive capsule, 30-60 parts of extender filler, and 10-30 parts of glass microspheres.

[0005] Furthermore, the molecular weight of the methyl methacrylate prepolymer is 3000-5000, and the solid content is 30%-50%.

[0006] Furthermore, the oxazolidine curing agent is selected from one or more of 1,3-oxazolidine, 2-isopropyl-1,3-oxazolidine, and 2-ethyl-4-methyl-1,3-oxazolidine.

[0007] Furthermore, the catalyst is one or more of organobismuth, organotin, or organozinc.

[0008] Furthermore, the filler material is one or more of carbonates, silicates, or metal oxides.

[0009] Furthermore, the adhesion promoter is one or more of a silane coupling agent, a titanate coupling agent, or a modified polyester coupling agent.

[0010] Furthermore, the isocyanate prepolymer is one or more of HDI, IPDI, or PDI.

[0011] Furthermore, the temperature-sensitive capsule is made of poly(N-isopropylacrylamide) material with a phase transition temperature of 30~40℃, and the core material is BPO curing agent.

[0012] The present invention adopts the above technical solution and has the following technical effects compared with the prior art: First, oxazolidine curing agents preferentially open their rings upon contact with water to form amino groups. These amino groups rapidly add to isocyanate prepolymers to form a flexible polyurethane network. The large amount of heat released during the reaction raises the system temperature above the phase transition temperature of the thermosensitive capsule, causing the capsule to rupture and release BPO. This, in turn, initiates the free radical polymerization of methyl methacrylate prepolymer to form a rigid PMMA network. The flexible and rigid networks interpenetrate to form an interpenetrating polymer network structure. Together, they endow the road marking paint with excellent flexibility, enabling it to adapt to the thermal expansion and contraction of the road surface without cracking. Second, the strain and weak bonds of the oxazolidine three-membered ring make it easy to open under the attack of water molecules. The isocyanate groups, due to the conjugation stabilization effect and steric hindrance, have a much lower hydrolysis rate than oxazolidine. Therefore, oxazolidine can preferentially react with moisture on the wet substrate, drying the interface and improving the wettability of the paint to the substrate, significantly enhancing the adhesion between the wet and wet interfaces. Furthermore, the isocyanate prepolymer is a linear oligomer with a high degree of freedom in molecular chain movement. The polyurethane network formed by the reaction with amino groups has high flexibility. At the same time, the exothermic reaction raises the system temperature, accelerating the rupture of the temperature-sensitive capsule and the free radical polymerization of the methyl methacrylate prepolymer, thus enabling rapid curing and drying even at low temperatures.

[0013] In summary, the road marking paint provided by this invention can be applied and cured at room temperature, and has the advantages of high toughness, rapid low-temperature curing, strong adhesion to wet interfaces, and good durability. Its overall performance is superior to that of existing two-component road marking paints. Detailed Implementation

[0014] The present invention will be further described below with reference to specific embodiments, but these are not intended to limit the invention. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other.

[0015] Experimental methods in the following examples, unless otherwise specified, were performed under standard conditions or as recommended by the manufacturer. Unless otherwise stated, all reagents and materials used in the following examples were commercially available.

[0016] Example 1 This embodiment provides a two-component, high-toughness, room-temperature curing road marking paint, comprising component A and component B with a mass ratio of 80:100; Component A, calculated by mass fractions, comprises: Methyl methacrylate prepolymer (molecular weight 4000, solid content 40%) 50 parts, oxazolidine curing agent (1,3-oxazolidine) 8 parts, catalyst (organic bismuth) 3 parts, extender filler (calcium carbonate) 45 parts, pigment (titanium dioxide) 12 parts, adhesion promoter (silane coupling agent KH-560) 0.5 parts, defoamer (BYK-066N) 1.0 part, dispersant (BYK-163) 1.5 parts; Component B includes: 35 parts of isocyanate prepolymer (HDI prepolymer, NCO content 12%), 15 parts of thermosensitive capsule (poly(N-isopropylacrylamide), phase change temperature 35℃, core material BPO), 45 parts of extender filler (talc), and 20 parts of glass microspheres (200 mesh).

[0017] The preparation method of the above-mentioned two-component high-toughness room-temperature curing road marking paint includes: Component A: Methyl methacrylate prepolymer was added to a reactor, and dispersant, adhesion promoter, defoamer, 1,3-oxazolidine and catalyst were added in sequence under stirring and dispersed evenly; then pigment and extender filler were added and stirred at high speed for 30 minutes to obtain component A.

[0018] Component B: Add the isocyanate prepolymer to the reactor, add the temperature-sensitive capsule and extender filler while stirring, and disperse for 20 minutes; finally add the glass microspheres and stir at low speed for 10 minutes to obtain Component B.

[0019] When using, mix components A and B in the specified ratio, spray the mixture onto the road surface (at room temperature) using the static mixer of a two-component line marking machine, and wait for complete cross-linking and curing.

[0020] The coating in this embodiment undergoes the following synergistic reaction after application, thereby achieving high toughness, rapid low-temperature drying, and strong wet-interface adhesion: (1) Oxazolidine curing agents preferentially undergo hydrolysis and ring-opening. The three-membered ring of oxazolidine preferentially opens upon contact with water to form an amino group (-NH2), which is the core reaction for adhesion to wet substrates. 1,3-oxazolidine (a typical oxazolidine curing agent) is a representative example.

[0021] Reactants: 1,3-oxazolidine, water; Product: 2-aminoethanol (containing an active amino group). This reaction occurs before the side reaction between isocyanate and water, thereby consuming the moisture on the substrate and drying the interface. At the same time, the generated amino group provides active sites for subsequent reactions.

[0022] (2) Addition reaction of amino groups with isocyanate prepolymer (exothermic, generating flexible polyurethane network) The amino groups generated by hydrolysis rapidly undergo an addition reaction with the HDI prepolymer (containing -NCO groups) in component B to form a flexible polyurethane network. This reaction releases a large amount of heat, increasing the overall temperature of the system. The reaction is illustrated below (with HDI representing the isocyanate prepolymer):

[0023] (3) The temperature-sensitive capsule releases BPO, which initiates free radical polymerization of PMMA prepolymer. When the system temperature reaches the phase transition temperature of the temperature-sensitive capsule (35°C in this example), the poly(N-isopropylacrylamide) capsule shell ruptures, releasing the core material BPO (benzoyl peroxide). The thermal decomposition of BPO generates active free radicals, which in turn initiate a free radical polymerization reaction of the methyl methacrylate prepolymer, forming a rigid PMMA network. 1) Thermal decomposition of BPO (generating reactive free radicals)

[0024] 2) Chain-growth polymerization of methyl methacrylate prepolymer

[0025] Ultimately, the flexible polyurethane network and the rigid PMMA network interpenetrate to form an interpenetrating polymer network (IPN) structure, producing a synergistic effect: the polyurethane network gives the coating high flexibility to adapt to the thermal expansion and contraction deformation of the road surface, the PMMA network provides strength and wear resistance, and the exothermic reaction accelerates the overall curing process, significantly shortening the drying time in low-temperature environments.

[0026] Example 2 This embodiment provides a two-component, high-toughness, room-temperature curing road marking paint, comprising component A and component B with a mass ratio of 82:100; Component A, calculated by mass fractions, comprises: Methyl methacrylate prepolymer (molecular weight 3500, solid content 30%) 40 parts, oxazolidine curing agent (2-isopropyl-1,3-oxazolidine) 10 parts, catalyst (organotin) 2 parts, extender filler (magnesium silicate) 50 parts, pigment (iron oxide yellow) 8 parts, adhesion promoter (titanium ester coupling agent NDZ-101) 0.6 parts, defoamer (BYK-066N) 0.5 parts, dispersant (BYK-163) 2 parts; Component B includes: 50 parts of isocyanate prepolymer (IPDI prepolymer, NCO content 10%), 10 parts of thermosensitive capsule (poly(N-isopropylacrylamide), phase change temperature 35℃, core material BPO), 30 parts of extender filler (quartz powder), and 30 parts of glass microspheres (150 mesh).

[0027] Comparative Example 1 This comparative example provides a two-component road marking paint, comprising component A and component B in a mass ratio of 80:100; Component A, calculated by mass fractions, comprises: Methyl methacrylate prepolymer (molecular weight 4000, solid content 40%) 50 parts, ethylenediamine (replacing 1,3-oxazolidine) 8 parts, catalyst (organo-bismuth) 3 parts, extender filler (calcium carbonate) 45 parts, pigment (titanium dioxide) 12 parts, adhesion promoter (silane coupling agent KH-560) 0.5 parts, defoamer (BYK-066N) 1.0 part, dispersant (BYK-163) 1.5 parts; Component B is exactly the same as in Example 1.

[0028] Comparative Example 2 This comparative example provides a two-component road marking paint, comprising component A and component B in a mass ratio of 80:100; In this case, component A, calculated by mass fractions, is exactly the same as in Example 1: Component B includes: 35 parts of isocyanate prepolymer (HDI prepolymer, NCO content 12%), 6 parts of BPO curing agent, 45 parts of extender filler (talc), and 20 parts of glass microspheres (200 mesh).

[0029] Performance testing: The performance of the road marking paints in Examples 1-2 and Comparative Examples 1-2 was tested, and the test standards and conditions are shown in Table 1 below: Table 1

[0030] The test results are shown in Table 2 below: Table 2

[0031] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the content of the present invention specification should be included within the protection scope of the present invention.

Claims

1. A two-component, high-toughness, room-temperature curing road marking paint, characterized in that, The road marking paint comprises component A and component B in a mass ratio of (75-85):100; Component A, calculated by mass fractions, comprises: 40-60 parts of methyl methacrylate prepolymer, 5-10 parts of oxazolidine curing agent, 1-5 parts of catalyst, 30-60 parts of extender filler, 5-20 parts of pigment, 0.3-0.7 parts of adhesion promoter, 0.5-1.5 parts of defoamer, and 1-2 parts of dispersant; Component B includes: 20-50 parts of isocyanate prepolymer, 10-20 parts of thermosensitive capsule, 30-60 parts of extender filler, and 10-30 parts of glass microspheres.

2. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The methyl methacrylate prepolymer has a molecular weight of 3000-5000 and a solid content of 30%-50%.

3. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The oxazolidine curing agent is selected from one or more of 1,3-oxazolidine, 2-isopropyl-1,3-oxazolidine, and 2-ethyl-4-methyl-1,3-oxazolidine.

4. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The catalyst is one or more of organobismuth, organotin, or organozinc.

5. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The filler material is one or more of carbonates, silicates, or metal oxides.

6. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The adhesion promoter is one or more of a silane coupling agent, a titanate coupling agent, or a modified polyester coupling agent.

7. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The isocyanate prepolymer is one or more of HDI, IPDI, or PDI.

8. The two-component, high-toughness, room-temperature curing road marking paint according to claim 1, characterized in that, The temperature-sensitive capsule is made of poly(N-isopropylacrylamide) with a phase change temperature of 30~40℃, and the core material is BPO curing agent.

Images