Amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating

Abstract

The invention relates to the technical field of coatings, and discloses an amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating, which comprises a component A: 100 parts of a water-borne epoxy resin emulsion, 5-20 parts of titanium dioxide, 1-2.5 parts of a dispersant, and 0.05-0.2 part of an antifoaming agent; the component B is prepared from 50 to 70 parts of amino-terminated ether-containing hyperbranched polyamide; the amino-terminated ether-containing hyperbranched polyamide contains an active amino-terminated group, so that the amino-terminated ether-containing hyperbranched polyamide is used as a curing agent and is subjected to a cross-linking curing reaction with epoxy resin, the hyperbranched polyamide has a three-dimensional branched network structure and forms a spatial cross-linked interpenetrating network system with the epoxy resin, and the hyperbranched polyamide contains a flexible ether-containing chain segment and an alkyl chain segment, so that the cross-linking property of the hyperbranched polyamide is improved. The epoxy resin coating has a good toughening effect, improves the impact resistance and impact strength of an epoxy resin coating layer and a casting body thereof, and keeps high hardness and tensile strength at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, in particular to an amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating. Background Art

[0002] In recent years, toughening and modifying waterborne epoxy resins and developing new epoxy resin materials have been research hotspots. The curing agent of epoxy resin contains curing hydrogen, which can cross-link and cure with epoxy resin, and has many effects on the performance of the cured coating. At present, the curing agents of epoxy resin mainly include amine curing agents, carboxylic acid curing agents, imidazole curing agents, etc.; among them, polymer curing agents such as polyamides and polyether amines have better modification effects on epoxy resins.

[0003] Patent CN113461960B discloses synthesizing a hyperbranched epoxy polymer with epoxy resin, trimethylolpropane and a catalyst; preparing a mono-terminated polyamine with n-butyl glycidyl ether and polyamine as raw materials; and finally synthesizing a modified waterborne epoxy curing agent with the hyperbranched epoxy polymer, epoxy resin and mono-terminated polyamine. The waterborne epoxy curing agent contains a hyperbranched structure, so that the cured coating film has good water resistance, high hardness and impact resistance. Therefore, using a hyperbranched polymer as a curing agent for epoxy resin is an effective method for improving the performance of epoxy resin. Summary of the invention

[0004] Technical problem solved: Provides an amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating, which solves the problems of low strength and poor impact resistance of epoxy resin coating.

[0005] Technical solution: A terminal amino group-containing ether-containing hyperbranched polyamide modified epoxy resin coating, characterized in that it comprises the following raw materials in parts by weight: component A: 100 parts of waterborne epoxy resin emulsion, 5-20 parts of titanium dioxide, 1-2.5 parts of dispersant, 0.05-0.2 parts of defoamer; component B: 50-70 parts of terminal amino group-containing ether-containing hyperbranched polyamide.

[0006] The amino-terminated ether-containing hyperbranched polyamide is prepared according to the following method: The structural formula is The ether-containing acrylate monomer and ethylenediamine are added to N,N-dimethylformamide, reacted at a temperature of 110-140°C for 10-18 hours, cooled, poured into methanol for precipitation, filtered, washed with ethanol, and dried at 60-70°C to obtain terminal amino-containing ether-containing hyperbranched polyamide.

[0007] Furthermore, the ratio of the acrylic acid ester monomer to ethylenediamine is 1 mol: (4.5-5) mol.

[0008] Further, the ether-containing acrylate monomer is prepared according to the following method: S1. Add methyl acrylate and 1-amino-3,6,9-trioxa-11-undecanol to methanol, reflux at 55-70°C for 24-36 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40-50°C to obtain intermediate A.

[0009] S2. Add intermediate A and hexamethylene diisocyanate to any one of tetrahydrofuran, 1,4-dioxane or toluene solvents, and reflux in a nitrogen atmosphere at 70-100°C for 3-5 h, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40-50°C to obtain an ether-containing acrylate monomer.

[0010] Furthermore, the ratio of methyl acrylate to 1-amino-3,6,9-trioxa-11-undecanol is (2.4-3.2) mol:1 mol.

[0011] Furthermore, in S3, the molar ratio of the intermediate A to hexamethylene diisocyanate is (2.2-2.5) mol:1 mol.

[0012] Furthermore, the curing method of the amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating is as follows: component A and component B are evenly mixed, first cured at 60-80°C for 1-2 h, then cured at 100-110°C for 2-4 h, and finally cured at 120-140°C for 2-4 h to obtain an epoxy resin coating.

[0013] The technical effect is that the amino-terminated ether-containing hyperbranched polyamide prepared by the present invention contains hydrophilic polyether, amide bonds and amino groups, so that the hyperbranched polyamide has good hydrophilicity and water solubility and can be well dispersed in a water-based epoxy resin coating matrix.

[0014] Compared with the traditional polyamide curing agent 651, the amino-terminated ether-containing hyperbranched polyamide of the present invention contains an active amino-terminated group, so that it can be used as a curing agent to undergo a cross-linking and curing reaction with the epoxy resin. The hyperbranched polyamide has a three-dimensional branched network structure and forms a spatially cross-linked interpenetrating network system with the epoxy resin. In addition, the hyperbranched polyamide contains flexible ether-containing segments and alkyl segments, which have a good toughening effect, improve the impact resistance and impact strength of the epoxy resin coating and its cast body, while maintaining a relatively high hardness and tensile strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the reaction route for the preparation of intermediate A.

[0016] Figure 2 It is a reaction route for preparing ether-containing acrylate monomers.

[0017] Figure 3It is a reaction route for preparing amino-terminated ether-containing hyperbranched polyamide. DETAILED DESCRIPTION

[0018] Example 1 Add 32 mmol of methyl acrylate and 10 mmol of 1-amino-3,6,9-trioxa-11-undecanol to methanol, reflux at 55°C for 30 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40°C to obtain intermediate A.

[0019] Add 11 mmol of intermediate A and 5 mmol of hexamethylene diisocyanate to tetrahydrofuran solvent, reflux at 70°C in a nitrogen atmosphere for 5 h, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40°C to obtain an ether-containing acrylate monomer.

[0020] 5 mmol of ether-containing acrylate monomer and 22.5 mmol of ethylenediamine were added to 20 mL of N,N-dimethylformamide, and the mixture was reacted at 120 °C for 12 h. After cooling, the solution was poured into methanol for precipitation, filtered, washed with ethanol, and dried at 60 °C to obtain amino-terminated ether-containing hyperbranched polyamide.

[0021] Component A: 100 parts of water-based epoxy resin emulsion, 10 parts of titanium dioxide, 1.5 parts of dispersant LW-110, 0.1 parts of defoamer 902w; component B: 50 parts of amino-terminated ether-containing hyperbranched polyamide, mix them evenly, first cure them at 80°C for 2 h, then cure them at 110°C for 3 h, and finally cure them at 120°C for 2 h to obtain an epoxy resin coating.

[0022] Example 2 Add 24 mmol of methyl acrylate and 10 mmol of 1-amino-3,6,9-trioxa-11-undecanol to methanol, reflux at 70°C for 24 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 45°C to obtain intermediate A.

[0023] 12.5 mmol of intermediate A and 5 mmol of hexamethylene diisocyanate were added to a toluene solvent, and the mixture was refluxed at 100°C for 4 h in a nitrogen atmosphere. The mixture was cooled, concentrated under reduced pressure, washed with n-hexane, and dried at 45°C to obtain an ether-containing acrylate monomer.

[0024] 5 mmol of ether-containing acrylate monomer and 25 mmol of ethylenediamine were added to 15 mL of N,N-dimethylformamide, and the mixture was reacted at 130 °C for 12 h. After cooling, the solution was poured into methanol for precipitation, filtered, washed with ethanol, and dried at 70 °C to obtain amino-terminated ether-containing hyperbranched polyamide.

[0025] Component A: 100 parts of water-based epoxy resin emulsion, 10 parts of titanium dioxide, 1.5 parts of dispersant LW-110, 0.1 parts of defoamer 902w; component B: 55 parts of amino-terminated ether-containing hyperbranched polyamide, mix them evenly, first cure them at 60°C for 3 h, then cure them at 100°C for 4 h, and finally cure them at 140°C for 2 h to obtain an epoxy resin coating.

[0026] Example 3 Add 28 mmol of methyl acrylate and 10 mmol of 1-amino-3,6,9-trioxa-11-undecanol to methanol, reflux at 60°C for 24 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40°C to obtain intermediate A.

[0027] Add 12 mmol of intermediate A and 5 mmol of hexamethylene diisocyanate to tetrahydrofuran solvent, reflux for 4 h at 70 °C in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40 °C to obtain an ether-containing acrylate monomer.

[0028] 5 mmol of ether-containing acrylate monomer and 23 mmol of ethylenediamine were added to 20 mL of N,N-dimethylformamide, and the mixture was reacted at 140 °C for 10 h. After cooling, the solution was poured into methanol for precipitation, filtered, washed with ethanol, and dried at 70 °C to obtain amino-terminated ether-containing hyperbranched polyamide.

[0029] Component A: 100 parts of water-based epoxy resin emulsion, 10 parts of titanium dioxide, 1.5 parts of dispersant LW-110, 0.1 parts of defoamer 902w; component B: 60 parts of amino-terminated ether-containing hyperbranched polyamide, mix them evenly, first cure them at 70°C for 1 hour, then cure them at 110°C for 2 hours, and finally cure them at 140°C for 4 hours to obtain an epoxy resin coating.

[0030] Example 4 Add 24 mmol of methyl acrylate and 10 mmol of 1-amino-3,6,9-trioxa-11-undecanol to methanol, reflux at 55°C for 36 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40°C to obtain intermediate A.

[0031] Add 12.5 mmol of intermediate A and 5 mmol of hexamethylene diisocyanate to 1,4-dioxane solvent, reflux at 90 °C for 4 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 40 °C to obtain an ether-containing acrylate monomer.

[0032] 5 mmol of ether-containing acrylate monomer and 22.5 mmol of ethylenediamine were added to 20 mL of N,N-dimethylformamide, and the mixture was reacted at 120 °C for 10 h. After cooling, the solution was poured into methanol for precipitation, filtered, washed with ethanol, and dried at 70 °C to obtain terminal amino-containing ether-containing hyperbranched polyamide.

[0033] Component A: 100 parts of water-based epoxy resin emulsion, 10 parts of titanium dioxide, 1.5 parts of dispersant LW-110, 0.1 parts of defoamer 902w; component B: 65 parts of amino-terminated ether-containing hyperbranched polyamide, mix them evenly, first cure them at 60°C for 2 h, then cure them at 110°C for 2 h, and finally cure them at 130°C for 4 h to obtain an epoxy resin coating.

[0034] Example 5 Add 24 mmol of methyl acrylate and 10 mmol of 1-amino-3,6,9-trioxa-11-undecanol to methanol, reflux at 60°C for 36 h in a nitrogen atmosphere, cool, concentrate under reduced pressure, wash with n-hexane, and dry at 50°C to obtain intermediate A.

[0035] 12 mmol of intermediate A and 5 mmol of hexamethylene diisocyanate were added to a toluene solvent, and the mixture was refluxed at 100°C for 4 h in a nitrogen atmosphere. The mixture was cooled, concentrated under reduced pressure, washed with n-hexane, and dried at 50°C to obtain an ether-containing acrylate monomer.

[0036] 5 mmol of ether-containing acrylate monomer and 25 mmol of ethylenediamine were added to 15 mL of N,N-dimethylformamide, and the mixture was reacted at 140 °C for 10 h. After cooling, the solution was poured into methanol for precipitation, filtered, washed with ethanol, and dried at 60 °C to obtain amino-terminated ether-containing hyperbranched polyamide.

[0037] Component A: 100 parts of water-based epoxy resin emulsion, 10 parts of titanium dioxide, 1.5 parts of dispersant LW-110, 0.1 parts of defoamer 902w; component B: 70 parts of amino-terminated ether-containing hyperbranched polyamide, mix them evenly, first cure them at 70°C for 2 h, then cure them at 100°C for 4 h, and finally cure them at 140°C for 3 h to obtain an epoxy resin coating.

[0038] Comparative Example 1 Component A: 100 parts of water-based epoxy resin emulsion, 10 parts of titanium dioxide, 1.5 parts of dispersant LW-110, 0.1 parts of defoamer 902w; component B: 50 parts of polyamide curing agent 651, mix them evenly, first cure them at 80°C for 2 h, then cure them at 110°C for 3 h, and finally cure them at 120°C for 2 h to obtain an epoxy resin coating.

[0039] The amino-terminated ether-containing hyperbranched polyamide was added to distilled water, stirred thoroughly, and prepared into solutions with different mass fractions. The solutions were allowed to stand for 48 h, and the state of the solutions was observed.

[0040]

[0041] The amino-terminated ether-containing hyperbranched polyamide has good hydrophilicity and water solubility and can be dispersed uniformly and stably in an aqueous medium.

[0042] The performance test of epoxy resin coating is as follows: Pencil hardness is tested according to GB / T 6739-2006.

[0043] Adhesion is tested according to GB / T 9286-2021 standard.

[0044] The impact resistance is tested according to GB / T 1732-2020 standard.

[0045]

[0046] Mix component A: water-based epoxy resin emulsion, titanium dioxide, dispersant LW-110, defoamer 902w; component B: polyamide curing agent 651, evenly, pour into the mold for casting, and perform heat curing. Test the impact strength and tensile strength according to the methods of GB / T2571-1995 and GB / T2567-2008.

[0047]

[0048] Compared with polyamide curing agent 651, the impact strength of epoxy resin reaches 21.4-32.0 kJ / m when amino-terminated ether-containing hyperbranched polyamide is used as epoxy resin curing agent. 2 , the tensile strength reaches 58.6-69.7MPa.

Claims

1. An amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating, characterized in that: The method comprises the following raw materials in parts by weight: component A: 100 parts of waterborne epoxy resin emulsion, 5-20 parts of titanium dioxide, 1-2.5 parts of dispersant, and 0.05-0.2 parts of defoamer; component B: 50-70 parts of amino-terminated ether-containing hyperbranched polyamide; The amino-terminated ether-containing hyperbranched polyamide is prepared according to the following method: The structural formula is The ether-containing acrylic ester monomer and ethylenediamine are added to N,N-dimethylformamide for reaction to obtain the amino-terminated ether-containing hyperbranched polyamide.

2. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 1, characterized in that: The ratio of the acrylic acid ester monomer to ethylenediamine is 1 mol: (4.5-5) mol.

3. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 1, characterized in that: The reaction is carried out at a temperature of 110-140°C for 10-18 h.

4. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 1, characterized in that: The ether-containing acrylate monomer is prepared according to the following method: S1. Add methyl acrylate and 1-amino-3,6,9-trioxa-11-undecanol to methanol, and reflux at 55-70° C. for 24-36 h in a nitrogen atmosphere to obtain intermediate A. S2. Add intermediate A and hexamethylene diisocyanate into the solvent in a nitrogen atmosphere to react and obtain an ether-containing acrylate monomer.

5. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 4, characterized in that: The ratio of the methyl acrylate to 1-amino-3,6,9-trioxa-11-undecanol is (2.4-3.2) mol:1 mol.

6. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 4, characterized in that: The solvent in S2 includes tetrahydrofuran, 1,4-dioxane or toluene.

7. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 4, characterized in that: In S3, the molar ratio of the intermediate A to hexamethylene diisocyanate is (2.2-2.5) mol:1 mol.

8. The amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating according to claim 4, characterized in that: The S3 reaction is refluxed at a temperature of 70-100°C for 3-5 h.

9. A method for curing the amino-terminated ether-containing hyperbranched polyamide modified epoxy resin coating as claimed in claim 1: uniformly mixing component A and component B, first curing at 60-80°C for 1-2 h, then curing at 100-110°C for 2-4 h, and finally curing at 120-140°C for 2-4 h to obtain an epoxy resin coating.

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