An n-octyl-2-hydroxybenzamide grafted polyaspartic ester polyurea resin, and a preparation method and application thereof

Abstract

The application discloses N-octyl-2-hydroxybenzamide grafted polyaspartic ester polyurea resin and a preparation method and application thereof, and the preparation method comprises the following steps: S10, uniformly mixing N-octyl-2-hydroxybenzamide grafted isocyanate prepolymer 15-35 parts, a solvent 2-10 parts and a catalyst 0.1-0.5 parts by weight to obtain an A component; S20, uniformly mixing polyaspartic ester 8-20 parts, a leveling agent 0.1-0.5 parts and a defoaming agent 0.1-0.5 parts by weight to obtain a B component; and S30, mixing the A component and the B component. The N-octyl-2-hydroxybenzamide grafted polyaspartic ester polyurea resin has better antifouling performance and mechanical properties than those of the prior art.

Description

Technical Field

[0001] This invention relates to the field of marine antifouling coating technology, specifically to an N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, its preparation method, and its application. Background Technology

[0002] Marine biofouling refers to damage to underwater facilities caused by the adhesion and invasion of marine organisms. Vulnerable underwater facilities include ships, docks, drainage pipes, oil platforms, and aquaculture facilities. The harm caused by marine biofouling is diverse. For example, mussels, barnacles, and large seaweed attach and grow on the bottom of ships, increasing their mass and drag, and the biofouling organisms adhering to the hull can also cause corrosion. Marine drilling organisms can damage docks; marine organisms can easily proliferate in drainage pipes, causing blockages. The economic losses caused by marine biofouling are enormous every year. Meanwhile, with the release of policies requiring ships entering ports to clean their hulls, the use of underwater cleaning combined with environmentally friendly antifouling paint has become the mainstream development trend.

[0003] Currently, resins on the market are divided into self-polishing resins and fouling-releasing resins. Self-polishing resins are mainly composed of zinc acrylate and copper acrylate as matrix resins, compounded with antifouling agents and functional fillers. The antifouling agents are released through the decomposition of the matrix resin in water to inhibit the attachment of marine organisms. However, the constantly evolving coatings mean that their wear resistance and washability cannot be guaranteed. Fouling-releasing resins are low surface energy resins, relying on their low surface energy characteristics to make it difficult for fouling organisms to adhere or easy to remove. The advantage of fouling-releasing coatings is that no inorganic substances are released during use, meeting green environmental protection requirements. However, they have weak adhesion to the substrate and poor mechanical properties, failing to meet the requirements for wear resistance and washability.

[0004] Chinese patent document CN108559375A discloses a polyaspartic acid ester polyurea anticorrosive coating containing polyaniline and its preparation method. The coating introduces intrinsic polyaniline, which has reversible redox properties, provides unparalleled anodic protection and shielding for metal materials, and exhibits special anticorrosive properties due to the strong adsorption of nitrogen atoms on the chain to metals. Therefore, it has excellent anticorrosive properties.

[0005] Chinese patent document CN113831822A discloses a method for manufacturing a high-performance polyurea composite material. The polyurea slurry is composed of components A, B, and C. Component A is composed of isocyanate; component B consists of liquid amine chain extender, polyaspartic acid ester, pigment, anti-settling agent, leveling agent, and additives; and component C consists of reinforcing fibers. The method improves the overall performance of the urea composite material by uniformly distributing 10-40 wt% of reinforcing fibers in the polyurea resin. The reinforcing fibers are S-type glass short fibers, E-type glass short fibers, or carbon short fibers.

[0006] Chinese patent document CN115418156A discloses a benzothiazole-modified polyaspartic acid ester polyurea antifouling coating, its preparation method and application. The invention introduces benzothiazole groups, which enable the polyaspartic acid ester polyurea system, which originally had no antifouling properties, to acquire a certain antifouling ability. Moreover, the generated urea-based structure can enhance adhesion through hydrogen bonds or chemical bonds, ensuring its wear resistance and cleaning resistance.

[0007] A search revealed no prior art disclosing N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, leading to the development of this invention. Summary of the Invention

[0008] Therefore, the purpose of this invention is to provide an N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, its preparation method and application, which has good antifouling properties and mechanical properties.

[0009] The technical solution adopted is as follows:

[0010] The present invention discloses an N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, which is prepared by mixing component A and component B, wherein:

[0011] Component A comprises the following components in parts by weight:

[0012] 15-35 parts of N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer

[0013] Solvent 2-10 parts,

[0014] Catalyst 0.1-0.5 parts;

[0015] Component B comprises the following components in parts by weight:

[0016] 8-20 parts of polyaspartic acid ester

[0017] Leveling agent 0.1-0.5 parts,

[0018] 0.1-0.5 parts of defoamer.

[0019] Furthermore, the N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer is prepared by the following steps:

[0020] S1. Methyl salicylate and n-octylamine are mixed and reacted completely at 140±2℃ to prepare N-octyl-2-hydroxybenzamide;

[0021] S2. Dehydrate the mixture of polypropylene glycol and polydimethylsiloxane;

[0022] S3. Mix polypropylene glycol, polydimethylsiloxane, N-octyl-2-hydroxybenzamide, and isophorone diisocyanate from S2, and carry out a prepolymerization reaction at 80-85℃ to obtain an N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer.

[0023] Furthermore, the molecular structure of the obtained N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer is as follows:

[0024]

[0025] Where m and n are natural numbers.

[0026] Further, in S1, the N-octyl-2-hydroxybenzamide is obtained by separating it after the reaction is complete by adding dichloromethane and 5% hydrochloric acid by mass. Preferably, in S1, methyl salicylate and n-octylamine are mixed and reacted completely at 140±2°C; after the reaction product is cooled to room temperature, dichloromethane and 5% hydrochloric acid by mass are added to separate the reaction product, dehydration is performed using anhydrous sodium sulfate, and dichloromethane is removed by rotary evaporation to obtain N-octyl-2-hydroxybenzamide.

[0027] Furthermore, in S1, the weight ratio of methyl salicylate to n-octylamine is 15.22:15.5.

[0028] Further, in S3, the weight ratio of N-octyl-2-hydroxybenzamide, polydimethylsiloxane, polypropylene glycol, and isophorone diisocyanate is 5:20:80:55.82. Preferably, the polypropylene glycol is used after being dehydrated and cooled under vacuum.

[0029] Further, the solvent is one or more of ethyl acetate, butyl acetate, and xylene. The solvent can dissolve the N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer, allowing it to react fully with component B and reducing the viscosity of the system.

[0030] Furthermore, the catalyst comprises one or more of dibutyltin dilaurate, triethylamine, cobalt naphthenate, and N-ethylmorpholine. The catalyst can accelerate the reaction.

[0031] In this invention, the leveling agent and defoamer can be commercially available, including but not limited to, for example, the leveling agent can be one of the commercially available BYK-306, BYK-307, and BYK-330 from Germany, and the defoamer can be one of the commercially available BYK-141, BYK-071, and BYK-060N from Germany.

[0032] A method for preparing the above-described N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to the present invention comprises the following steps:

[0033] S10. By weight, 15-35 parts of N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer, 2-10 parts of solvent, and 0.1-0.5 parts of catalyst are mixed evenly to obtain component A;

[0034] S20. By weight, 8-20 parts of polyaspartic acid ester, 0.1-0.5 parts of leveling agent, and 0.1-0.5 parts of defoamer are mixed evenly to obtain component B;

[0035] S30. Mix component A and component B.

[0036] The present invention relates to the application of the above-described N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin as a marine antifouling coating, wherein the N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin is coated on a substrate and then cured.

[0037] In this invention, the substrate material includes one or more of glass, steel, wood, plastic, and bakelite.

[0038] In this invention, the thickness of the resin coating on the substrate is not specifically limited; the thickness can be set as needed.

[0039] In this invention, the curing temperature is preferably 80-85℃. This invention does not specify the curing time; it is sufficient to form a dry film with the coating.

[0040] In this invention, when the resin is applied to marine antifouling, it is preferably coated on the surface of marine equipment. This invention does not specifically limit the thickness of the resin coating on the surface of marine equipment; it can be set according to the actual situation.

[0041] In this invention, polyaspartic acid ester is an isocyanate curing agent containing a secondary amine structure. Compared to primary amines, its reaction rate is slower but more controllable, allowing for more processing time. The ester groups and aliphatic properties in its structure can increase the hardness of the coating. Combined with the N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer in component A, it imparts good toughness and elasticity to the resin, resulting in a coating with excellent impact and abrasion resistance. Furthermore, the introduction of N-octyl-2-hydroxybenzamide into the N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer in component A gives the coating better antifouling and mechanical properties.

[0042] By grafting N-octyl-2-hydroxybenzamide into the side chains of polyaspartic acid ester polyurea resin, steric hindrance is increased, the reaction rate is slowed down, thereby improving the adhesion of the substrate; on the other hand, the complexity of the molecular network structure is increased, the microstructure of the coating is improved, thereby enhancing the waterproofness and impact resistance of the coating.

[0043] N-Octyl-2-hydroxybenzamide is a non-leaching antifouling agent. Experimental results show that N-octyl-2-hydroxybenzamide grafted onto polyaspartic acid ester polyurea resin has better antifouling ability; its amide groups easily form hydrogen bonds with the substrate, which further increases adhesion.

[0044] In summary, the beneficial effects of the present invention are as follows:

[0045] The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin of the present invention has better antifouling properties and mechanical properties than the prior art. Detailed Implementation

[0046] The present invention will be described in detail below through specific embodiments. However, the uses and purposes of these exemplary embodiments are only for illustrating the present invention and do not constitute any limitation on the actual protection scope of the present invention, nor are they intended to limit the protection scope of the present invention to these embodiments.

[0047] Unless otherwise specified, "parts" in the following examples refer to parts by weight.

[0048] Example 1

[0049] This embodiment provides a method for preparing N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, comprising the following steps:

[0050] 15.22 parts of methyl salicylate were added to the reaction apparatus, along with 15.5 parts of n-octylamine. The mixture was heated to 140°C and reacted for 10 hours with stirring. After the reaction was complete, the mixture was cooled to room temperature. Dichloromethane and 50 mL of 5% hydrochloric acid solution were added to form a layer. The bottom layer was removed and washed with 10% ammonium bicarbonate solution until neutral. This process was repeated three times. 5 parts of anhydrous sodium sulfate were added to the separated organic phase to dehydrate it, yielding a pale pink solid, which is N-octyl-2-hydroxybenzamide.

[0051] 20 parts of hydroxypropyl silicone oil and 80 parts of polypropylene glycol were added to the reaction apparatus. The mixture was heated to 105°C under vacuum to remove water. After dehydration, the mixture was cooled to below 50°C. 55.82 parts of isophorone diisocyanate, 5 parts of N-octyl-2-hydroxybenzamide, and 0.2 parts of dibutyltin dilaurate were added dropwise. After mixing evenly, the mixture was heated to 80-85°C and reacted for 2.5 hours to obtain N-octyl-2-hydroxybenzamide grafted isocyanate prepolymer.

[0052] Component A comprises 34.11 parts of N-octyl-2-hydroxybenzamide grafted isocyanate prepolymer, 5.1 parts of solvent, and 0.2 parts of catalyst.

[0053] Component B consists of 16.90 parts of polyaspartic acid ester (NH1220), 0.5 parts of defoamer, and 0.5 parts of leveling agent.

[0054] 39.41 parts of component A and 17.90 parts of component B were mixed and stirred evenly, and the mixture was degassed under vacuum to obtain resin. The resin was then coated onto a steel substrate and cured at a temperature of 80-85℃ to obtain an anti-fouling coating.

[0055] Example 2

[0056] This embodiment provides an N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, which is composed of component A and component B;

[0057] Component A comprises 19.47 parts of N-octyl-2-hydroxybenzamide grafted isocyanate prepolymer, 2.9 parts of solvent, and 0.2 parts of catalyst.

[0058] Component B comprises 1.17 parts of polyaspartic acid ester NH1420, 8.68 parts of polyaspartic acid ester NH1220, 0.5 parts of defoamer, and 0.5 parts of leveling agent.

[0059] When using, mix component A and component B evenly and cure at a temperature of 80-85℃.

[0060] Example 3

[0061] This embodiment provides an N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, which is composed of component A and component B;

[0062] Component A comprises 19.70 parts of N-octyl-2-hydroxybenzamide grafted isocyanate prepolymer, 3.0 parts of solvent, and 0.2 parts of catalyst;

[0063] Component B comprises 2.35 parts of polyaspartic acid ester NH1420, 7.83 parts of polyaspartic acid ester NH1220, 0.5 parts of defoamer, and 0.5 parts of leveling agent.

[0064] When using, mix component A and component B evenly and cure at a temperature of 80-85℃.

[0065] Comparative Example 1

[0066] This comparative example provides a polysiloxane-modified polyaspartic acid ester polyurea resin, which is composed of component A and component B;

[0067] 20 parts of hydroxypropyl silicone oil and 80 parts of polypropylene glycol were added to the reaction apparatus. The mixture was heated to 105°C under vacuum to remove water. After dehydration, the mixture was cooled to below 50°C. 55.82 parts of isophorone diisocyanate and 0.2 parts of dibutyltin dilaurate were added dropwise. After mixing evenly, the mixture was heated to 80-85°C and reacted for 2.5 hours to obtain a polysiloxane-modified isocyanate prepolymer.

[0068] Component A comprises 23.66 parts of polysiloxane-modified isocyanate prepolymer, 3.49 parts of solvent, and 0.2 parts of catalyst;

[0069] Component B consists of 11.19 parts of polyaspartic acid ester NH1220, 0.5 parts of defoamer, and 0.5 parts of leveling agent.

[0070] When using, mix component A and component B evenly and cure at a temperature of 80-85℃.

[0071] Comparative Example 2

[0072] This comparative example provides a polysiloxane-modified polyaspartic acid ester polyurea resin, which is composed of component A and component B;

[0073] Component A comprises 33.16 parts of polysiloxane-modified isocyanate prepolymer, 5.3 parts of solvent, and 0.2 parts of catalyst;

[0074] Component B comprises 2.36 parts of polyaspartic acid ester NH1420, 17.51 ​​parts of polyaspartic acid ester NH1220, 0.5 parts of defoamer, and 0.5 parts of leveling agent.

[0075] When using, mix component A and component B evenly and cure at a temperature of 80-85℃.

[0076] Comparative Example 3

[0077] This comparative example provides a polysiloxane-modified polyaspartic acid ester polyurea resin, which is composed of component A and component B;

[0078] Component A comprises 27.50 parts of polysiloxane-modified isocyanate prepolymer, 4.4 parts of solvent, and 0.2 parts of catalyst;

[0079] Component B comprises 3.90 parts of polyaspartic acid ester NH1420, 12.86 parts of polyaspartic acid ester NH1220, 0.5 parts of defoamer, and 0.5 parts of leveling agent.

[0080] When using, mix component A and component B evenly and cure at a temperature of 80-85℃.

[0081] Test 1

[0082] Mussel adhesion rate test: Using a blank glass slide as a control, the sample and the glass slide were placed in a glass jar containing mussels at the same time. After two days, the number of mussel byssal threads adhering to the glass and the sample of the example were observed. The inhibition rate was expressed as the ratio of the difference between the number of byssal threads on the sample and the number of byssal threads on the glass slide to the number of byssal threads on the glass slide.

[0083] The results are as follows: Compared with Comparative Example 1, which inhibited mussel attachment by 54.22%, Experimental Example 1 inhibited mussel attachment by 97.12%; compared with Comparative Example 2, which inhibited mussel attachment by 58.02%, Experimental Example 2 inhibited mussel attachment by 98.24%; compared with Comparative Example 3, which inhibited mussel attachment by 60.38%, Experimental Example 3 inhibited mussel attachment by 97.54%.

[0084] Test 2

[0085] Coating Adhesion Test: This paper tests the adhesion of coatings applied to steel plates according to standard GB / T 5210-2006. The coating thickness is approximately 200 μm, and the aluminum alloy cylinder diameter is 20 mm. A clean aluminum alloy cylinder and the sample are bonded together with adhesive and allowed to stand for 48 hours. A pull-out test is performed using a Positest-AT-M tensile testing machine. During the pull-out process, stress is applied perpendicular to the substrate, and the pull-out speed is 0.2 MPa per second. The value at which the cylinder detaches from the substrate surface is recorded. Five different points are randomly selected from each sample for testing, and the average value is taken as the final result.

[0086] The results are as follows: Compared with the adhesion of 2.72 MPa in Comparative Example 1, the adhesion of Experimental Example 1 increased to 3.67 MPa; compared with the adhesion of 3.24 MPa in Comparative Example 2, the adhesion of Experimental Example 2 increased to 4.79 MPa; compared with the adhesion of 5.03 MPa in Comparative Example 3, the adhesion of Experimental Example 3 increased to 5.28 MPa.

[0087] The detailed descriptions listed above are merely specific illustrations of feasible embodiments of the present invention and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. An N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin, characterized in that, It is made by mixing component A and component B, wherein: Component A comprises the following components in parts by weight: 15-35 parts of N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer Solvent 2-10 parts, Catalyst 0.1-0.5 parts; The N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer was prepared by the following steps: S1. Methyl salicylate and n-octylamine are mixed and reacted completely at 140±2℃ to prepare N-octyl-2-hydroxybenzamide; S2. Dehydrate the mixture of polypropylene glycol and polydimethylsiloxane; S3. Mix polypropylene glycol, polydimethylsiloxane, N-octyl-2-hydroxybenzamide, and isophorone diisocyanate from S2 and carry out a prepolymerization reaction at 80-85℃ to obtain an N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer. Component B comprises the following components in parts by weight: 8-20 parts of polyaspartic acid ester Leveling agent 0.1-0.5 parts, 0.1-0.5 parts of defoamer.

2. The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to claim 1, characterized in that, In S3, the molecular structure of the N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer obtained is as follows: , where m and n are natural numbers.

3. The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to claim 1, characterized in that, In S1, the N-octyl-2-hydroxybenzamide is obtained by adding dichloromethane and 5% hydrochloric acid after the reaction is complete.

4. The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to claim 1, characterized in that, In S1, the weight ratio of methyl salicylate to n-octylamine is 15.22:15.

5.

5. The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to claim 1, characterized in that, In S3, the weight ratio of N-octyl-2-hydroxybenzamide, polydimethylsiloxane, polypropylene glycol, and isophorone diisocyanate is 5:20:80:55.

82.

6. The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to claim 1, characterized in that, The solvent is one or more of ethyl acetate, butyl acetate, and xylene.

7. The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to claim 1, characterized in that, The catalyst includes one or more of dibutyltin dilaurate, triethylamine, cobalt naphthenate, and N-ethylmorpholine.

8. A method for preparing the N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to any one of claims 1-7, characterized in that, Includes the following steps: S10. By weight, 15-35 parts of N-octyl-2-hydroxybenzamide-grafted isocyanate prepolymer, 2-10 parts of solvent, and 0.1-0.5 parts of catalyst are mixed evenly to obtain component A; S20. By weight, 8-20 parts of polyaspartic acid ester, 0.1-0.5 parts of leveling agent, and 0.1-0.5 parts of defoamer are mixed evenly to obtain component B; S30. Mix component A and component B.

9. The application of the N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin according to any one of claims 1-7 as a marine antifouling coating, characterized in that, The N-octyl-2-hydroxybenzamide-grafted polyaspartic acid ester polyurea resin was coated onto the substrate and then cured.

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