PMMA (polymethyl methacrylate) two-component road marking paint

Abstract

The invention discloses a PMMA (polymethyl methacrylate) bi-component road marking coating, and belongs to the field of production of road marking coatings. The marking paint is prepared by mixing a component A and a component B, wherein the component A is mainly prepared from a dispersing agent, an anti-settling agent, an anti-aging agent, PMMA (polymethyl methacrylate) resin, an amine curing agent, hydroxypropyl resin, methacrylate modified silane, pigment and filler; the component B is prepared from benzoyl peroxide and an isocyanate prepolymer according to the mass ratio of (5 to 15) to (85 to 95). Compared with the prior art, the road marking coating disclosed by the invention not only improves the defect of slow low-temperature curing and film forming of PMMA (Polymethyl Methacrylate) double-component marking coating, but also improves the flexibility while having hardness, and has excellent comprehensive performance and very good popularization and application values.

Description

Technical Field

[0001] This invention relates to the field of road marking paint production, specifically providing a method for preparing PMMA two-component road marking paint. Background Technology

[0002] PMMA two-component road marking paint is one of the most common chemical cross-linking and curing paints in the existing technology. It uses polymethyl methacrylate as the film-forming material. Although it has good wear resistance and weather resistance, it has poor flexibility and slow film formation at low temperature, which makes the film prone to cracking after construction, easy to warp at the edges, and limited applicable areas. Summary of the Invention

[0003] This invention addresses the shortcomings of the prior art by providing a PMMA two-component road marking paint that not only overcomes the slow film formation at low temperatures of existing PMMA two-component road marking paints, but also possesses both good hardness and flexibility.

[0004] The technical solution adopted by this invention to solve its technical problem is: PMMA two-component road marking paint, composed of component A and component B, characterized in that the mass ratio of component A to component B is 100:(10-30). Component A is mainly prepared from the following raw materials in the indicated weight ratios: Dispersant 0.2-0.5 parts Anti-settling agent 0.2-0.5 parts Anti-aging agent 0.1-0.3 parts 20-40 parts PMMA resin 5-15 parts of amine curing agent 5-15 parts of hydroxypropyl resin 0.5-1 part of methacrylate-modified silane 5-15 parts of pigment 35-45 parts of filler; Component B consists of peroxybenzoyl and isocyanate prepolymers in a mass ratio of (5-15):(85-95).

[0005] Preferably, the mass ratio of component A to component B is 100:(15-25).

[0006] As a preferred embodiment, the weight ratio of each raw material in component A is as follows: Dispersant 0.3-0.4 parts Anti-settling agent 0.3-0.4 parts Anti-aging agent 0.15-0.25 parts 25-35 parts PMMA resin 8-12 parts of amine curing agent 8-12 parts of hydroxypropyl resin 0.5–0.8 parts of methacrylate-modified silane 8-12 parts of pigment 35-40 parts of filler.

[0007] Preferably, the dispersant is BYK-163.

[0008] Preferably, the anti-settling agent is BYK-410.

[0009] Preferably, the anti-aging agent is BASF Tinuvin 292.

[0010] Preferably, the filler is 800-mesh heavy calcium carbonate powder, with an 800-mesh pass rate of over 90% and a whiteness of over 90.

[0011] Preferably, the amine curing agent is a polyaspartic acid ester resin (such as Bayer NH1420), a polymer with an amine terminal active functional group (such as HUANGMA D2000), or (3,3'-dimethyl-4,4'-diaminodicyclohexylmethane (such as BASF Laromin C260)).

[0012] Preferably, the methacrylate-modified silane is γ-methacryloyloxypropyltrimethoxysilane (TMSPMA).

[0013] As a preferred embodiment, the preparation method of component A is as follows: S1. Add PMMA resin, amine curing agent, hydroxypropyl resin and methacrylate modified silane to a container and stir at 300-400 rpm for 2-3 minutes to mix thoroughly. Then, while stirring, add dispersant, anti-settling agent and anti-aging agent in sequence. Add pigment while keeping the speed constant, increase the speed to 800-1000 rpm and disperse for about 10 minutes. Add filler while keeping the speed constant and disperse for about 20 minutes. S2. Filter and dispense to obtain component A as the finished product.

[0014] Preferably, the mass ratio of peroxybenzoyl to isocyanate prepolymer is (8-12):(88-92).

[0015] Preferably, the isocyanate prepolymer is a hexamethylene diisocyanate trimer and / or an isophorone diisocyanate prepolymer.

[0016] As a preferred embodiment, the preparation method of component B is as follows: S1. Add the isocyanate prepolymer to the container, and while stirring at 300-400 rpm, add liquid benzoyl peroxide and continue stirring to mix thoroughly. S2. Filter and dispense to obtain component B as the finished product.

[0017] When using, add component B to component A, stir thoroughly, and then apply it to the road surface by spraying or scraping.

[0018] Compared with existing technologies, the PMMA two-component road marking paint of the present invention has the following outstanding advantages: (i) By introducing medium- and long-chain polyamines containing unsaturated bonds and hydroxyl acrylic resins, and using isocyanate prepolymers and benzoyl peroxide as reaction aids, PMMA provides a rigid skeleton, the amino resin crosslinking network enhances cohesion, hydroxypropyl resin imparts flexibility, benzoyl peroxide initiates the polymerization reaction of PMMA to form a dense network, the isocyanate prepolymer undergoes an addition reaction with hydroxyl acrylic acid to form polyurethane soft segments, and the isocyanate prepolymer undergoes a rapid polycondensation reaction with polyamines to provide high mechanical strength, thus enabling the PMMA two-component road marking paint of the present invention to achieve an excellent balance between flexibility and wear resistance; (ii) Methacrylate-modified silane can improve resin compatibility and enhance the anti-fouling ability after film formation. The resulting coating structure is dense and can resist the intrusion of dust, oil and other contaminants for a long time, so that the markings can maintain a good retroreflective brightness coefficient for a long time. (III) The nitrogen atoms in the amine curing agent donate electrons to form a charge-transfer complex with benzoyl peroxide, reducing the decomposition activation energy of benzoyl peroxide. Even at low temperatures (e.g., -10 to -30°C), it can accelerate the decomposition of benzoyl peroxide to generate free radicals. These free radicals can simultaneously initiate the polymerization of the methacrylate double bonds in PMMA resin and the unsaturated double bonds in hydroxypropyl resin, forming a cross-linked network. The PMMA-hydroxypropyl copolymer formed by the participation of the double-bonded hydroxypropyl segments in free radical polymerization reduces phase separation and improves the low-temperature brittleness of the coating film. The free radicals generated by the decomposition of benzoyl peroxide rapidly initiate the rapid cross-linking and grafting of the double bonds in PMMA and hydroxypropyl resin onto the existing polyurea backbone, giving the PMMA two-component road marking paint of this invention excellent low-temperature rapid curing performance and construction performance. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments, but this is not intended to limit the present invention. Example

[0020] Material Proportioning The weight ratio of each raw material in the PMMA two-component road marking paint of this embodiment is shown in the table below:

[0021]

Preparation Method

[0022]

Experimental Example

[0023] The performance results above, along with the comparative results, show that pure PMMA two-component resin coatings have poor flexibility, easily causing cracking and edge warping in the marking film. However, when combined with hydroxypropyl resin and multi-component hydroxypropyl resin, the reaction of hydroxypropyl resin with isocyanate prepolymer generates polyurethane soft segments, improving the toughness of the film. The microphase separation structure of polyurea and polyurethane achieves nanoscale synergy between soft and hard segments, enabling entropy change in the soft segments upon impact. The low Tg of the polyether soft segments in the resin (-50℃) imparts low-temperature elasticity to the material. The urea bonds in the polyurea can still form reversible hydrogen bonds at low temperatures, reducing stress concentration and allowing the coating to self-repair micro-damage after stress relief. These combined effects significantly improve the flexibility of the coating. The network crosslinking density formed by the reaction of hydroxypropyl resin and isocyanate groups is much higher than that of linear PMMA, increasing surface hardness and significantly enhancing the coating's scratch resistance. The polysiloxane introduced into the resin forms a low surface energy in the coating, reducing the coefficient of friction and minimizing the cutting action of abrasive particles on the coating surface.

[0024] Pure PMMA two-component resin coatings cure slowly at low temperatures. However, when combined with polyamines and hydroxypropyl resin, they maintain high reactivity even at -30°C. The nitrogen atoms in the amine molecules donate electrons to form charge-transfer complexes with BPO, lowering the activation energy of BPO decomposition. Even at low temperatures (e.g., -30°C), this accelerates the decomposition of BPO to generate free radicals. These free radicals can simultaneously initiate the polymerization of the methacrylate double bonds in PMMA resin and the unsaturated double bonds in hydroxypropyl resin. The reactivity of the amino groups in amines with isocyanate groups is much higher than that of the hydroxyl groups (amino groups are more nucleophilic). At low temperatures, they preferentially combine with isocyanate groups to form urea bonds, releasing heat (exothermic reaction) and indirectly increasing the local system temperature, which in turn promotes the reaction between hydroxyl and isocyanate groups. Some amine curing agents can act as nucleophilic catalysts, forming intermediates with isocyanate groups to lower the activation energy of the reaction between hydroxyl and isocyanate groups, allowing the hydroxy-isocyanate reaction, which is normally difficult to occur at low temperatures, to proceed smoothly.

[0025] Compared to pure PMMA resin, the combination of polyamines and hydroxypropyl resin results in a highly cross-linked network formed by the reaction of hydroxypropyl resin and isocyanate groups, which effectively prevents stain molecules from penetrating into the coating. The methacrylate-modified silane added to the resin participates in the free radical copolymerization of PMMA / hydroxypropyl resin, embedding into the polymer network and constructing a chemical bond bridge of "substrate-Si-OC-polymer," significantly improving adhesion. The surface-enriched "-Si-O-Si-" bond angle is 144°, forming a low-energy surface that greatly enhances the hydrophobicity and anti-fouling ability of the coating.

Claims

1. A PMMA two-component road marking paint, composed of component A and component B, characterized in that: The mass ratio of component A to component B is 100:(10~30). Component A is mainly prepared from the following raw materials in the indicated weight ratios: Dispersant 0.2-0.5 parts Anti-settling agent 0.2-0.5 parts Anti-aging agent 0.1-0.3 parts 20-40 parts PMMA resin 5-15 parts of amine curing agent 5-15 parts of hydroxypropyl resin 0.5-1 part of methacrylate-modified silane 5-15 parts of pigment 35-45 parts of filler; Component B consists of peroxybenzoyl and isocyanate prepolymers in a mass ratio of (5-15):(85-95).

2. The PMMA two-component road marking paint according to claim 1, characterized in that: The mass ratio of component A to component B is 100:(15-25).

3. The PMMA two-component road marking paint according to claim 1, characterized in that: The weight ratio of each raw material in component A is as follows: Dispersant 0.3-0.4 parts Anti-settling agent 0.3-0.4 parts Anti-aging agent 0.15-0.25 parts 25-35 parts PMMA resin 8-12 parts of amine curing agent 8-12 parts of hydroxypropyl resin 0.5–0.8 parts of methacrylate-modified silane 8-12 parts of pigment 35-40 parts of filler.

4. The PMMA two-component road marking paint according to claim 1, 2 or 3, characterized in that: The dispersant is BYK-163; The anti-settling agent is BYK-410; The anti-aging agent is BASF Tinuvin 292; The filler is 800-mesh heavy calcium carbonate powder, with an 800-mesh pass rate of over 90% and a whiteness of over 90.

5. The PMMA two-component road marking paint according to claim 1, 2 or 3, characterized in that: The amine curing agent is polyaspartic acid ester resin, a polymer with amine as the terminal active functional group, or 3,3'-dimethyl-4,4'-diaminodicyclohexylmethane; The methacrylate-modified silane is γ-methacryloyloxypropyltrimethoxysilane.

6. The PMMA two-component road marking paint according to claim 1, 2 or 3, characterized in that: The preparation method of component A is as follows: S1. Add PMMA resin, amine curing agent, hydroxypropyl resin and methacrylate modified silane to a container and stir at 300-400 rpm for 2-3 minutes to mix thoroughly. Then, while stirring, add dispersant, anti-settling agent and anti-aging agent in sequence. Add pigment while keeping the speed constant, increase the speed to 800-1000 rpm and disperse for about 10 minutes. Add filler while keeping the speed constant and disperse for about 20 minutes. S2. Filter and dispense to obtain component A as the finished product.

7. The PMMA two-component road marking paint according to claim 1 or 2, characterized in that: The mass ratio of peroxybenzoyl to isocyanate prepolymer is (8-12):(88-92).

8. The PMMA two-component road marking paint according to claim 1 or 2, characterized in that: The isocyanate prepolymer is hexamethylene diisocyanate trimer and / or isophorone diisocyanate prepolymer.

9. The PMMA two-component road marking paint according to claim 1 or 2, characterized in that: The preparation method of component B is as follows: S1. Add the isocyanate prepolymer to the container, and while stirring at 300-400 rpm, add liquid benzoyl peroxide and continue stirring to mix thoroughly. S2. Filter and dispense to obtain component B as the finished product.

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