Isothiazolinone non-curing coating and preparation method thereof

Abstract

The invention discloses an isothiazolinone non-curing coating and a preparation method thereof, and relates to the technical field of waterproof coatings. The coating comprises a base material, a compound isothiazolinone antibacterial agent, a mixed stabilizer, a compound plasticizer, a compound anti-aging agent, a filler, an adhesion promoter and a solvent, the compound type isothiazolinone antibacterial agent is prepared by mixing and compounding 2-methyl-4-isothiazolin-3-ketone and 5-chloro-2-methyl-4-isothiazolin-3-ketone according to a mass ratio of (1 to 3): 1, and the compound type isothiazolinone antibacterial agent is prepared by mixing and compounding 2-methyl-4-isothiazolin-3-ketone and 5-chloro-2-methyl-4-isothiazolin-3-ketone and 5-chloro-2-methyl-4-isothiazolin-3-ketone; the mixed stabilizer is formed by mixing organic bentonite, polyamide wax and fumed silica; the defects that an existing non-curing coating is poor in antibacterial performance, insufficient in aging resistance and poor in formula compatibility are overcome.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waterproof coating, in particular to a non-curing coating of isothiazolinone and a preparation method thereof. BACKGROUND

[0002] Non-curing coating has been widely used in the field of waterproofing and corrosion protection due to its characteristics of long-term viscous state, no curing shrinkage, and tight adhesion to the base layer. However, the existing non-curing coating has the following technical defects. First, the antibacterial performance is insufficient, and in a humid and dark environment, it is easy to breed microorganisms such as mold and bacteria, resulting in mold spots on the coating surface, degradation, and reduction of protective effect and service life. Second, the aging resistance is poor: long-term exposure to ultraviolet light, high and low temperature cycles and other natural environments, easy to crack, powder, adhesion decline and other problems. Third, the formula compatibility is poor: traditional antibacterial agents (such as organic tin and phenolic compounds) have poor compatibility with the base material (such as rubber and asphalt) of non-curing coating, which can cause delamination and precipitation, affecting the construction performance and overall stability of the coating.

[0003] As a highly effective and broad-spectrum antibacterial agent, isothiazolinone compounds have the advantages of strong antibacterial activity, low toxicity, and environmental friendliness, and have been applied to water-based coatings. However, when directly applied to non-curing coating, it faces problems such as uneven dispersion, easy migration and loss, and poor compatibility with the base material, resulting in short antibacterial effect duration and difficulty in balancing the physical and mechanical properties of the coating. Therefore, it is a technical problem to be solved in the field to develop a non-curing coating that can stably disperse isothiazolinone antibacterial agents in the coating system, while having excellent antibacterial, aging resistance and adhesion. SUMMARY

[0004] The present application aims to provide a non-curing coating of isothiazolinone and a preparation method thereof to overcome the defects of poor antibacterial performance, insufficient aging resistance and poor formula compatibility of existing non-curing coating.

[0005] To solve the above problems, the following technical means are adopted: A non-curing coating of isothiazolinone, comprising a base material, a compounded isothiazolinone antibacterial agent, a mixed stabilizer, a compounded plasticizer, a compounded anti-aging agent, a filler, an adhesion promoter and a solvent. The compounded isothiazolinone antibacterial agent is mixed and compounded by 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one in a mass ratio of 1-3:1. The mixed stabilizer is mixed by organic bentonite, polyamide wax and fumed silica.

[0006] The complex isothiazolinone antibacterial agent system can expand the antibacterial spectrum and improve the antibacterial efficiency; the mixed stabilizer can effectively prevent the antibacterial agent and the filler from settling and improve the stability of the system.

[0007] Preferably, the base material is compounded by 20-40% of butyl rubber, 30-50% of SBS modified asphalt and 20-30% of EVA resin.

[0008] In this way, the viscosity, elasticity and weather resistance of the coating can be considered by compounding the base material.

[0009] Further, the complex plasticizer is compounded by dioctyl phthalate and epoxy soybean oil at a mass ratio of 2-3:1.

[0010] The coating as a whole can ensure the construction fluidity of the coating and improve the low-temperature flexibility thereof.

[0011] Further, the complex anti-aging agent is compounded by benzotriazole ultraviolet absorber and hindered phenolic antioxidant at a mass ratio of 1-2:1.

[0012] In this way, the anti-aging agent can be compounded to improve the ultraviolet resistance and thermal-oxidative aging resistance of the coating.

[0013] Further, the filler includes one or more of heavy calcium carbonate, talcum powder and mica powder.

[0014] Further, the adhesion promoter includes one of silane coupling agent and titanate coupling agent.

[0015] Further, the solvent is compounded by dimethylbenzene and ethyl acetate at a mass ratio of 3-5:1.

[0016] Further, the base material is 30-50 parts by weight, the complex isothiazolinone antibacterial agent is 0.5-3 parts by weight, the mixed stabilizer is 1-5 parts by weight, the complex plasticizer is 5-15 parts by weight, the complex anti-aging agent is 1-4 parts by weight, the filler is 20-40 parts by weight, the adhesion promoter is 0.5-2 parts by weight, and the solvent is 5-10 parts by weight.

[0017] Further, a preparation method of the foregoing isothiazolinone non-curing coating, comprising the following steps: S1. A formula amount of base material is added to a reaction kettle, and heated and melted under stirring to obtain a base material molten liquid; S2. The solvent, the complex isothiazolinone antibacterial agent and the mixed stabilizer are stirred and mixed to obtain a pre-dispersion liquid; S3. The pre-dispersed liquid is mixed with the base melt, followed by the addition of the compounded plasticizer, compounded anti-aging agent and adhesion promoter; S4. The filler is added to the mixture obtained in step S3, and the particle size of the material is controlled to be no more than 50 μm; S5. The ground material is transferred to a reaction kettle, cooled to 80-100℃, and kept at this temperature for 10-15 min under stirring, and then cooled to 60-70℃ and discharged for packaging.

[0018] Preferably, in step S1, heating is carried out to 160-180℃, the speed is 300-500 r / min, and the melting is kept for 30-40 min.

[0019] The present application has the following advantages: The antibacterial agent is stably dispersed by using the antibacterial agent stable dispersion technology, the synergistic effect of the compounded isothiazolinone antibacterial agent and the mixed stabilizer, the space steric hindrance effect and the adsorption effect of the mixed stabilizer, the antibacterial agent particles are wrapped and uniformly dispersed in the base system, and the agglomeration and migration of the antibacterial agent are avoided.

[0020] The base is compounded and optimized, the high elasticity and air permeability resistance of butyl rubber, the adhesion of SBS modified asphalt and the flexibility of EVA resin are combined, and a base system with viscosity, elasticity and weather resistance is formed.

[0021] Moreover, the anti-aging and adhesion synergistically improve the aspect, the compounded system of the anti-aging agent can inhibit the degradation of the coating in harsh environment, the adhesion promoter can improve the interfacial compatibility and enhance the bonding force between the coating and the base layer, and the long-term use performance of the coating is improved.

[0022] The coating prepared in the present application has excellent long-acting antibacterial performance. The isothiazolinone antibacterial agent is stably dispersed under the action of the mixed stabilizer, the antibacterial rate of escherichia coli, staphylococcus aureus and aspergillus niger is all ≥ 99%, and after 500 h of water immersion test, the antibacterial rate is still maintained at more than 98%, solving the problem of easy mold of traditional non-curing coating.

[0023] After 1000 h of ultraviolet aging test, the coating has no cracking and pulverization phenomenon, the tensile strength retention rate is ≥ 90%, and the elongation at break retention rate is ≥ 85%; after 50 times of high and low temperature cycle of-20℃ to 60℃, the bonding strength decrease rate is ≤ 10%, which is much better than the existing non-curing coating. The adhesion with the concrete base layer is ≥ 1.5 MPa, and the adhesion with the metal base layer is ≥ 1.2 MPa; at 25℃, the viscosity of the coating is maintained at 50000-80000 mPa・s, and there is no delamination and precipitation phenomenon after long-term storage (6 months), and the construction fluidity is good.

[0024] The low-toxicity isothiazolinone antibacterial agent meets the environmental protection requirements; the filling material is reasonably used in the formula, the preparation process is simple, and the cost is reduced by 10-15% compared to the same antibacterial non-curing coating. DETAILED DESCRIPTION

[0025] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application.

[0026] Therefore, the following detailed description of the embodiments of the present application is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative labor are within the scope of protection of the present application.

[0027] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0028] An isothiazolinone non-curing coating, comprising a base material, a compounded isothiazolinone antibacterial agent, a mixed stabilizer, a compounded plasticizer, a compounded anti-aging agent, a filling material, an adhesion promoter and a solvent. The compounded isothiazolinone antibacterial agent is compounded by mixing 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one at a mass ratio of 1-3:1. The mixed stabilizer is mixed by organic bentonite, polyamide wax and fumed silica.

[0029] The compounded isothiazolinone antibacterial agent system can expand the antibacterial spectrum and improve the antibacterial efficiency; the mixed stabilizer can effectively prevent the antibacterial agent and the filling material from settling and improve the system stability.

[0030] As preferred, the base material is compounded by 20-40% of butyl rubber, 30-50% of SBS modified asphalt and 20-30% of EVA resin.

[0031] In this way, the compounding of the base material can take into account the viscosity, elasticity and weather resistance of the coating.

[0032] Further, the compounded plasticizer is compounded by mixing dioctyl phthalate and epoxy soybean oil at a mass ratio of 2-3:1.

[0033] So that the coating as a whole can ensure the construction fluidity of the coating and improve its low-temperature flexibility.

[0034] Further, the compounded anti-aging agent is compounded by benzotriazole ultraviolet absorber and hindered phenol antioxidant at a mass ratio of 1-2:1.

[0035] In this way, the compounded anti-aging agent can synergistically improve the anti-ultraviolet and anti-thermal aging performance of the coating.

[0036] Further, the filler includes one or more of heavy calcium carbonate, talcum powder and mica powder.

[0037] Further, the adhesion promoter includes one of silane coupling agent and titanate coupling agent.

[0038] Further, the solvent is compounded by xylene and ethyl acetate at a mass ratio of 3-5:1.

[0039] Further, the base is 30-50 parts by weight, the compounded isothiazolinone antibacterial agent is 0.5-3 parts by weight, the mixed stabilizer is 1-5 parts by weight, the compounded plasticizer is 5-15 parts by weight, the compounded anti-aging agent is 1-4 parts by weight, the filler is 20-40 parts by weight, the adhesion promoter is 0.5-2 parts by weight, and the solvent is 5-10 parts by weight.

[0040] Further, a preparation method of the foregoing isothiazolinone non-curing coating, comprising the following steps: S1. A formula amount of base is added to a reaction kettle, and heated and melted under stirring to obtain a base melt; S2. The solvent, the compounded isothiazolinone antibacterial agent and the mixed stabilizer are stirred and mixed to obtain a pre-dispersion; S3. The pre-dispersion is mixed with the base melt, and then the compounded plasticizer, the compounded anti-aging agent and the adhesion promoter are added; S4. The filler is added to the mixture obtained in step S3, and the particle size of the material is controlled to be not more than 50 μm; S5. The ground material is transferred to the reaction kettle, cooled to 80-100 °C, and kept at 80-100 °C for 10-15 min under stirring, and then cooled to 60-70 °C and discharged for packaging.

[0041] As preferred, in step S1, heating is performed to 160-180 °C, the heating rate is 300-500 r / min, and the holding time is 30-40 min.

[0042] The following is described based on a specific embodiment. According to the above formula and preparation process, three examples are set up, and the specific formula composition (parts by weight) is shown in the following table:

[0043] Three comparative examples were set up, in which, in comparative example 1, no isothiazolinone antibacterial agent and mixing stabilizer were added, and the remaining components and preparation process were the same as in example 1. In comparative example 2, the isothiazolinone antibacterial agent was directly added without adding the mixing stabilizer, and the remaining components and preparation process were the same as in example 1. In comparative example 3, a single base (SBS modified asphalt) was selected, and no butyl rubber and EVA resin were compounded, and the remaining components and preparation process were the same as in example 1.

[0044] The coatings of the aforementioned examples 1 to 3 and comparative examples 1 to 3 were tested for performance, and the final results showed that the antibacterial rates of examples 1-3 were all ≥99%, and still maintained a high level after immersion, indicating that the isothiazolinone antibacterial agent was stably dispersed under the action of the dispersion stabilizer, effectively avoiding migration and loss; the antibacterial rate of comparative example 1 was extremely low due to the absence of the antibacterial agent; the antibacterial agent in comparative example 2 was prone to agglomeration due to the absence of the dispersion stabilizer, not only the initial antibacterial rate was lower than that of the examples, but also the antibacterial rate decreased significantly (only 75.3%) after immersion, verifying the key role of the dispersion stabilizer.

[0045] Examples 1-3 had excellent performance retention rate after ultraviolet aging and high-low temperature cycle, and the tensile strength retention rate after ultraviolet aging was above 93%; comparative example 3 had a tensile strength retention rate of only 75.2% after ultraviolet aging due to the use of a single base, and the lack of synergistic effect of butyl rubber and EVA resin, and the adhesive strength decreased to 1.05 MPa after high-low temperature cycle, proving that the base compounding scheme can significantly improve the aging resistance.

[0046] The adhesive forces of examples 1-3 were all ≥1.5 MPa, and no delamination occurred after 6 months of storage, indicating that the adhesion promoter effectively improved the interfacial bonding force, and the dispersion stabilizer ensured the stability of the system; comparative example 2 had serious delamination due to the absence of the dispersion stabilizer; comparative example 3 had a low adhesive force and slight cracking due to the single base, further demonstrating the rationality of the formula of the present application.

[0047] Therefore, the present application successfully solves the technical problems of poor antibacterial performance, insufficient aging resistance, and poor formula compatibility of existing non-curing coatings by optimizing the formula composition (base compounding, synergistic effect of antibacterial agent and dispersion stabilizer, and collocation of anti-aging agent and adhesion promoter) and preparation process of isothiazolinone non-curing coatings.

[0048] From the performance test result, the coating has the characteristics of long-acting antibiosis (antibiosis rate is greater than or equal to 99%, still greater than or equal to 98% after immersion), excellent aging resistance (tensile strength retention rate is greater than or equal to 90% after ultraviolet aging, and bonding strength is stable after high-low temperature cycle), strong adhesion (adhesion to concrete is greater than or equal to 1.5 MPa) and good storage stability (no delamination for 6 months), meanwhile, the cost is controllable, the process is simple, and the coating is suitable for industrial production, has wide application prospect in the fields of building waterproofing, pipeline anticorrosion and ship protection, and has remarkable economic and social benefits.

[0049] Although the present application has been described in detail with reference to the foregoing embodiments, technical solutions recorded in the foregoing embodiments can be modified or some technical features can be replaced by equivalent ones by those skilled in the art, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An isothiazolinone-based non-curing coating, characterized in that, Includes base material, compound isothiazolinone antibacterial agent, mixed stabilizer, compound plasticizer, compound anti-aging agent, filler, adhesion promoter and solvent; The compound isothiazolinone antibacterial agent is a mixture of 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one in a mass ratio of 1 to 3:

1. The mixed stabilizer is composed of organobentonite, polyamide wax and fumed silica.

2. The isothiazolinone-based non-curing coating according to claim 1, characterized in that, The base material is composed of 20-40% butyl rubber, 30-50% SBS modified asphalt, and 20-30% EVA resin.

3. The isothiazolinone-based non-curing coating according to claim 1, characterized in that, The compound plasticizer is a mixture of dioctyl phthalate and epoxidized soybean oil in a mass ratio of 2 to 3:

1.

4. The isothiazolinone-based non-curing coating according to claim 1, characterized in that, The compound anti-aging agent is a mixture of benzotriazole ultraviolet absorbers and hindered phenolic antioxidants in a mass ratio of 1 to 2:

1.

5. The isothiazolinone-based non-curing coating according to claim 1, characterized in that, The filler includes one or more of heavy calcium carbonate, talc, and mica powder.

6. The isothiazolinone-based non-curing coating according to claim 1, characterized in that, The adhesion promoter includes one of silane coupling agents and titanate coupling agents.

7. An isothiazolinone-based non-curing coating according to claim 1, characterized in that, The solvent is prepared by compounding xylene and ethyl acetate in a mass ratio of 3 to 5:

1.

8. An isothiazolinone-based non-curing coating according to any one of claims 1 to 7, characterized in that, By weight, the base material comprises 30-50 parts, the compound isothiazolinone antibacterial agent comprises 0.5-3 parts, the mixed stabilizer comprises 1-5 parts, the compound plasticizer comprises 5-15 parts, the compound anti-aging agent comprises 1-4 parts, the filler comprises 20-40 parts, the adhesion promoter comprises 0.5-2 parts, and the solvent comprises 5-10 parts.

9. A method for preparing an isothiazolinone-based non-curing coating according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1. Add the base material of the formula to the reaction vessel, heat and melt it under stirring to obtain the base material melt; S2. Mix the solvent, compound isothiazolinone antibacterial agent, and mixed stabilizer to obtain a pre-dispersion; S3. Mix the pre-dispersed liquid with the base material melt, and then add the compound plasticizer, compound anti-aging agent and adhesion promoter; S4. Add the filler to the mixture obtained in step S3, and control the particle size of the material to not exceed 50μm; S5. Transfer the ground material to the reactor, cool it to 80~100℃, keep it warm for 10~15 minutes while stirring, then cool it to 60~70℃ before discharging and packaging.

10. The preparation method according to claim 9, characterized in that, In step S1, the temperature is heated to 160~180℃, the heating rate is 300~500r / min, and the temperature is held for melting for 30~40min.

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