Impact-resistant enhanced structural ink and preparation method thereof

Abstract

The invention discloses impact-resistant enhanced structural ink and a preparation method thereof. The impact-resistant enhanced structural ink is prepared from the following raw materials in percentage by weight: 1-5% of silicon dioxide nanofiller, 1-3% of monomer microcapsules, 10-20% of resin matrix, 50-60% of glass powder and the balance of auxiliaries, and the auxiliaries comprise a dispersing agent and pigment. The silicon dioxide nanofiber is introduced, so that the impact resistance of the ink is enhanced, and crack propagation under dynamic impact is avoided through a 1.5 m drop test. By introducing the DCPD monomer microcapsules, the DCPD monomer microcapsules release monomers to repair cracks under dynamic impact, the self-repairing function is achieved, and the service life of the ink layer is prolonged.

Description

Technical Field

[0001] This invention relates to the field of inks, and more specifically to an impact-resistant reinforced structural ink and its preparation method. Background Technology

[0002] Printing inks can be applied to the surfaces of many products. However, traditional inks lack sufficient impact resistance after drying and curing, making them prone to cracking or peeling after dynamic impacts, leading to ink layer failure. Existing improvements involve increasing the hardness of the ink layer by introducing rigid materials like ceramics or increasing its thickness to enhance impact resistance. However, this also reduces the ink layer's flexibility and adhesion to flexible substrates. Furthermore, existing ink layers lack self-healing properties, affecting their lifespan. Therefore, developing an ink layer with good impact resistance, flexibility, and self-healing capabilities is crucial.

[0003] Chinese invention patent CN112680030B discloses a conductive microcapsule and graphene conductive ink, its preparation method, and its application. The conductive microcapsule uses a composite material of graphene and low-melting-point polyurethane as the core material, amino resin as the wall material, and conductive metal particles deposited on the surface. It has good conductive self-healing function, capable of repairing microcracks in the graphene conductive film and extending the service life of the material, but it does not significantly improve the impact resistance. Chinese invention patent application CN112552778A discloses a self-detection and self-healing smart coating containing microcapsules and its preparation method. By adding microcapsules with self-detection and self-healing functional molecules, it diversifies its functions, giving the coating self-healing while also having a self-detection function. However, it has poor flexibility and insufficient adhesion to flexible substrates. Summary of the Invention

[0004] In order to develop an ink layer with good impact resistance, good flexibility and self-healing function, the first aspect of the present invention provides an impact-resistant reinforced structure ink, wherein the raw materials for preparation include, by weight percentage, 1-5% silica nanofiller, 1-3% monomer microcapsules, 10-20% resin matrix, 50-60% glass powder, 0.05-1% catalyst, and additives to 100%, wherein the additives include dispersants and pigments.

[0005] In one embodiment, the raw materials for preparation include, by weight percentage, 1-5% silica nanofiller, 1-3% monomer microcapsules, 10-20% resin matrix, 50-60% glass powder, 0.05-1% catalyst, 0.5-2% dispersant, and 10-30% pigment.

[0006] In one embodiment, the raw materials for preparation include, by weight percentage, 2% silica nanofiller, 2% monomer microcapsules, 19% resin matrix, 50% glass powder, 1.9% dispersant, 0.1% catalyst, and 25% pigment.

[0007] In one embodiment, the silica nanofiller is silica nanofiber.

[0008] In one embodiment, the aspect ratio of the silica nanofibers is ≥10.

[0009] In one embodiment, the length of the silica nanofibers is 80-100 μm and the diameter of the silica nanofibers is 5-15 μm.

[0010] In one embodiment, the length of the silica nanofiber is 90 μm and the diameter of the silica nanofiber is 9 μm.

[0011] During their experiments, the inventors discovered that using silica nanofibers with a preferred aspect ratio can improve the impact resistance of inks. This is likely because the silica nanofibers can be directionally dispersed in the ink, forming a three-dimensional network support structure that can disperse dynamic stress and inhibit crack propagation. The inventors further found that silica nanofibers with a preferred aspect ratio have stronger compressive strength; using silica nanofibers with an aspect ratio exceeding the preferred ratio in the ink results in decreased impact resistance and reduced self-healing ability.

[0012] In one embodiment, the monomer microcapsules are DCPD (dicyclopentadiene) monomer microcapsules with a particle size of 1-5 μm.

[0013] In one embodiment, the raw materials for preparing the DCPD monomer microcapsules include dicyclopentadiene, an aqueous emulsifier solution, and a wall material mixture, wherein the mass concentration of the aqueous emulsifier solution is 0.1-1%.

[0014] In one embodiment, the emulsifier aqueous solution comprises an emulsifier and deionized water, wherein the emulsifier is Tween.

[0015] In one embodiment, the Tween includes at least one of Tween-40, Tween-60, and Tween-80.

[0016] In one implementation, the Tween is Tween-80.

[0017] In one embodiment, the wall material mixture comprises isocyanate, toluene, and ethylenediamine, wherein the volume ratio of isocyanate to toluene is 1:(1-3); and the molar ratio of isocyanate to ethylenediamine is (1-5):1.

[0018] In one embodiment, the wall material mixture comprises isocyanate, toluene, and ethylenediamine, wherein the volume ratio of isocyanate to toluene is 1:1, and the molar ratio of isocyanate to ethylenediamine is 3:1.

[0019] In one embodiment, the isocyanate is isophorone diisocyanate.

[0020] In one embodiment, the mass ratio of the dicyclopentadiene to the emulsifier aqueous solution is 1:(3-8).

[0021] In one embodiment, the mass ratio of the dicyclopentadiene to the emulsifier aqueous solution is 1:5.

[0022] In one embodiment, the catalyst is benzenemethylene dichlorobis(tricyclohexylphosphine)ruthenium (first-generation Grubbs).

[0023] As one embodiment, the method for preparing the DCPD monomer microcapsules includes the following steps:

[0024] Preparation of emulsifier aqueous solution;

[0025] Dicyclopentadiene was added to an aqueous emulsifier solution and emulsified at 1000-2000 rpm for 20-40 min under nitrogen protection to obtain an emulsion.

[0026] Mix isocyanate and toluene, add ethylenediamine dropwise under ice bath, and stir for 5-15 minutes to obtain wall material mixture;

[0027] The wall material mixture is added dropwise to the emulsion at 0-5℃, and then the temperature is increased to 50-70℃ at a rate of 1℃ / min, and the mixture is stirred at 500-700rpm for 1-5 hours.

[0028] After centrifugation, washing, and freeze-drying, DCPD monomer microcapsules were obtained.

[0029] In one embodiment, the dropping rate is 0.05 mL / s.

[0030] In one embodiment, the centrifugation speed is 2500-3500 rpm and the centrifugation time is 5-15 min.

[0031] In one embodiment, the washing is performed by washing with ethanol or water 1-3 times.

[0032] During the experiment, the inventors discovered that adding DCPD monomer microcapsules to ink can give the ink a self-healing function and automatically repair micro-cracks. The reason may be that when DCPD monomer microcapsules are embedded in ink, when subjected to dynamic impact, cracks will be generated, causing the capsules to rupture and release the monomer contact catalyst in the DCPD monomer microcapsules, which will undergo in-situ polymerization to repair the film layer, thereby automatically repairing micro-cracks.

[0033] As one embodiment, the method for preparing the glass powder includes the following steps:

[0034] The raw materials are mixed, heated in stages in an air atmosphere to 1000-1500℃, kept at a constant temperature for 1-3 hours, quenched in ice water, dried at 70-90℃, ball-milled with media, dried and sieved to obtain glass powder.

[0035] In one embodiment, the raw materials for preparing the glass powder include, by weight percentage, 30% SiO2, 1% Al2O3, 7% B2O3, 4% Li2CO3, 8% ZnO, and 50% Bi2O3.

[0036] In one embodiment, the ball milling is a zirconia ball milling process, the ball milling speed is 300-500 rpm, the ball milling time is 3-8 hours, and the medium for the media ball milling is water.

[0037] As one implementation method, the D50 after ball milling is measured to be 2.5 μm.

[0038] In one implementation, the sieving process involves first passing the material through a 50-mesh sieve and then through a 400-mesh sieve.

[0039] In one embodiment, the resin matrix is ​​an aqueous acrylic resin.

[0040] In one embodiment, the dispersant is a polycarboxylate dispersant.

[0041] A second aspect of the present invention provides a method for preparing an impact-resistant reinforced structural ink, comprising the following steps:

[0042] The silica nanofiller, catalyst, dispersant and resin matrix are mixed and sonicated for 40-50 min to obtain a dispersion.

[0043] Add the monomer microcapsules to the dispersion and stir at 300-500 rpm until homogeneous;

[0044] Glass powder and pigments are added and ground to a fineness of ≤5μm to obtain an impact-resistant reinforced structural ink.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] (1) The impact-resistant reinforced structure ink of the present invention enhances the impact resistance of the ink by introducing silica nanofibers and avoids crack propagation under dynamic impact by passing a 1.5m drop test.

[0047] (2) The impact-resistant reinforced structure ink of the present invention uses silica nanofibers with an aspect ratio ≥10. While maintaining the ink's flexibility without increasing the ink layer thickness and hardness, it avoids the problem of high hardness and insufficient toughness that occurs after introducing silica nanoparticles.

[0048] (3) The impact-resistant reinforced structural ink of the present invention is lightweight, flexible, and has good adhesion to flexible substrates.

[0049] (4) The impact-resistant reinforced structure ink of the present invention introduces DCPD monomer microcapsules. When subjected to dynamic impact, the DCPD monomer microcapsules release monomers to repair cracks, which has a self-healing function and extends the service life of the ink layer.

[0050] (5) The impact-resistant reinforced structural ink of the present invention uses self-made glass powder, which is ball-milled to reduce the particle size, thereby enabling the repair of fine cracks and improving the efficiency of self-repair. Detailed Implementation

[0051] Example 1

[0052] An impact-resistant reinforced structural ink, wherein the raw materials for preparation include, by weight percentage, 2% silica nanofiller, 2% monomer microcapsules, 19% resin matrix, 50% glass powder, 1.9% dispersant, 0.1% catalyst, and 25% pigment.

[0053] The silica nanofiller is silica nanofiber with a length of 90 μm, a diameter of 9 μm, and an aspect ratio of 10. It was purchased from Lianyungang Ruichuang New Materials Technology Co., Ltd., and its grade is SX-80.

[0054] The monomer microcapsules are DCPD monomer microcapsules with a particle size of 1-5 μm. The raw materials for preparation include dicyclopentadiene, an aqueous emulsifier solution, and a wall material mixture. The mass concentration of the aqueous emulsifier solution is 0.5%.

[0055] The emulsifier aqueous solution is an emulsifier and deionized water, and the emulsifier is Tween-80.

[0056] The wall material mixture comprises isophorone diisocyanate, toluene, and ethylenediamine, wherein the volume ratio of isocyanate to toluene is 1:1, and the molar ratio of isocyanate to ethylenediamine is 3:1.

[0057] The catalyst is benzenemethylene dichlorobis(tricyclohexylphosphine)ruthenium (first generation Grubbs).

[0058] The method for preparing the DCPD monomer microcapsules includes the following steps:

[0059] Preparation of emulsifier aqueous solution: Dissolve 0.25g of emulsifier in 49.75g of deionized water;

[0060] Add 10g of dicyclopentadiene to an aqueous emulsifier solution and emulsify at 1500rpm for 30min under nitrogen protection to obtain an emulsion;

[0061] Mix 3.4 g of isocyanate with 3.4 mL of toluene, add 0.68 g of ethylenediamine dropwise under ice bath, and stir for 10 min to obtain a wall material mixture;

[0062] The wall material mixture was added dropwise to the emulsion at 0-5℃, and then the temperature was increased to 60℃ at a rate of 1℃ / min, and the mixture was stirred at 600rpm for 4 hours.

[0063] After centrifugation at 3000 rpm for 10 min, washing with ethanol three times, and freeze-drying, DCPD monomer microcapsules were obtained.

[0064] The raw materials for preparing the glass powder include, by weight percentage, 30% SiO2, 1% Al2O3, 7% B2O3, 4% Li2CO3, 8% ZnO, and 50% Bi2O3.

[0065] The method for preparing the glass powder includes the following steps:

[0066] The raw materials were mixed, heated in stages to 1200℃ in air atmosphere, kept at a constant temperature for 2 hours, quenched in ice water, dried at 80℃, ball-milled with media, vacuum dried at 60℃ and sieved to obtain glass powder.

[0067] The ball milling process involves adding zirconia, with a milling speed of 400 rpm and a milling time of 5 hours. The medium used in the media milling process is water.

[0068] The D50 value after ball milling is 2.5 μm. The sieving process involves first passing the material through a 50-mesh sieve and then through a 400-mesh sieve.

[0069] The resin matrix is ​​a water-based acrylic resin, purchased from Guangdong Keding Functional Materials Co., Ltd., with the grade VA326.

[0070] The dispersant is a polycarboxylate dispersant, purchased from Guangdong Zhongke Hongtai New Materials Co., Ltd., with the brand name DK064.

[0071] The pigment was purchased from Jiangxi Jinhuan Pigment Co., Ltd., and its brand name is JH2822B.

[0072] A method for preparing an impact-resistant reinforced structural ink includes the following steps:

[0073] The silica nanofiller, catalyst, dispersant and resin matrix were mixed and sonicated for 45 min to obtain a dispersion.

[0074] Add the monomer microcapsules to the dispersion and stir at 400 rpm until homogeneous;

[0075] Glass powder and pigments are added and ground to a fineness of ≤5μm to obtain an impact-resistant reinforced structural ink.

[0076] Example 2

[0077] An impact-resistant reinforced structural ink and its preparation method are disclosed. The raw materials for preparation include, by weight percentage, 4% silica nanofiller, 2.5% monomer microcapsules, 19% resin matrix, 50.5% glass powder, 1.9% dispersant, 0.1% catalyst, and 22% pigment.

[0078] The remaining implementation methods are the same as in Example 1.

[0079] Example 3

[0080] An impact-resistant reinforced structural ink and its preparation method are disclosed. The raw materials for preparation include, by weight percentage, 1% silica nanofiller, 1% monomer microcapsules, 19% resin matrix, 51% glass powder, 2% dispersant and 26% pigment.

[0081] The remaining implementation methods are the same as in Example 1.

[0082] Comparative Example 1

[0083] An impact-resistant reinforced structural ink and its preparation method are disclosed, with the specific implementation method being the same as in Example 1. The difference lies in that the silica nanofiller is silica nanoparticles with a D50 of 100 nm.

[0084] The silica nanoparticles were purchased from Lianyungang Miaojing Silicon Materials Co., Ltd., and the grade is RR325.

[0085] Comparative Example 2

[0086] An impact-resistant reinforced structural ink and its preparation method are disclosed, with the specific implementation method being the same as in Example 1. The difference lies in that the silica nanofiller is silica nanofiber with a length of 65 μm, a diameter of 13 μm, and an aspect ratio of 5, purchased from Lianyungang Ruichuang New Materials Technology Co., Ltd., with the grade SX-80 (customized version).

[0087] Comparative Example 3

[0088] An impact-resistant reinforced structural ink and its preparation method are disclosed. The raw materials for preparation include, by weight percentage, 2% silica nanofiller, 20% resin matrix, 50% glass powder, 1.9% dispersant, 0.1% catalyst, and 26% pigment.

[0089] The remaining implementation methods are the same as in Example 1.

[0090] Performance test sample preparation: The inks prepared in the examples and comparative examples were coated on standard glass (100mm×100mm×3mm, surface roughness Ra=0.8μm), with a wet film thickness of 25μm, and cured at 700℃ for 2min. Three samples were prepared for each group, and the average value was taken for testing.

[0091] 1. Impact resistance: Refer to DIN 52337, test the drop test of a 1kg steel ball at different heights.

[0092] 2. Self-healing efficiency test:

[0093] 2.1 Pre-introduced crack: Using a micro-scratcher, a single straight crack with a length of 2 mm and a width ≤ 50 μm was introduced into the coating surface. The crack location was marked in the center area of ​​the sample.

[0094] 2.2 Initial fracture strength test: A three-point bending tester (span 60 mm, loading speed 1 mm / min) was used to record the load value (F0) when the cracked area first fractured.

[0095] Fracture strength calculation formula: σ0=3F0L / 2bh 2 (L = span, b = sample width, h = coating thickness)

[0096] 2.3 Self-healing process: Place the cracked sample in an environment of 25℃ and 60% relative humidity for 24 hours without external stimulation.

[0097] 2.4 Fracture strength test after repair: Under the same conditions as in step 2.2, test the fracture strength (F1) after repair and calculate the strength σ1 after repair.

[0098] Self-repair efficiency calculation: Self-repair efficiency = (σ0 / σ1) × 100%.

[0099] 3. Flexibility test: Refer to ASTM D522 to test the flexibility of bending.

[0100] The test results are shown in Table 1.

[0101] Table 1

[0102] Test Project Impact resistance Self-repair efficiency flexibility Example 1 1.5m intact 85％ No cracking at 180° Example 2 1.6m intact 87％ 150° cracking Example 3 1.3m intact 78％ No cracking at 180° Comparative Example 1 1.2m breakage 82％ 90° bending crack Comparative Example 2 1.3m damage 78％ 180° bending crack Comparative Example 3 1.5m breakage 0％ No cracking at 180°

[0103] The impact-resistant reinforced structural ink prepared in this application has the advantages of being lightweight and highly flexible, and can automatically repair micro-cracks.

Claims

1. An impact-resistant reinforced structural ink, characterized in that, The raw materials for preparation include, by weight percentage, 1-5% silica nanofiller, 1-3% monomer microcapsules, 10-20% resin matrix, 50-60% glass powder, 0.05-1% catalyst, and additives to 100%, including dispersants and pigments.

2. The impact-resistant reinforced structural ink according to claim 1, characterized in that, The silica nanofiller is silica nanofiber.

3. The impact-resistant reinforced structural ink according to claim 2, characterized in that, The aspect ratio of the silica nanofibers is ≥10.

4. The impact-resistant reinforced structural ink according to claim 1, characterized in that, The monomer microcapsules are DCPD monomer microcapsules with a particle size of 1-5 μm.

5. The impact-resistant reinforced structural ink according to claim 4, characterized in that, The raw materials for preparing the DCPD monomer microcapsules include dicyclopentadiene, an aqueous emulsifier solution, and a wall material mixture, wherein the mass concentration of the aqueous emulsifier solution is 0.1-1%.

6. The impact-resistant reinforced structural ink according to claim 5, characterized in that, The wall material mixture comprises isocyanate, toluene, and ethylenediamine, wherein the volume ratio of isocyanate to toluene is 1:(1-3); and the molar ratio of isocyanate to ethylenediamine is (1-5):

1.

7. The impact-resistant reinforced structural ink according to claim 5, characterized in that, The mass ratio of the dicyclopentadiene to the emulsifier aqueous solution is 1:(3-8).

8. The impact-resistant reinforced structural ink according to claim 6, characterized in that, The method for preparing the DCPD monomer microcapsules includes the following steps: Preparation of emulsifier aqueous solution; Dicyclopentadiene was added to an aqueous emulsifier solution and emulsified at 1000-2000 rpm for 20-40 min under nitrogen protection to obtain an emulsion. Mix isocyanate and toluene, add ethylenediamine dropwise under ice bath, and stir for 5-15 minutes to obtain wall material mixture; The wall material mixture is added dropwise to the emulsion at 0-5℃, and then the temperature is increased to 50-70℃ at a rate of 1℃ / min, and the mixture is stirred at 500-700rpm for 1-5 hours. After centrifugation, washing, and freeze-drying, DCPD monomer microcapsules were obtained.

9. The impact-resistant reinforced structural ink according to claim 1, characterized in that, The method for preparing the glass powder includes the following steps: The raw materials are mixed, heated in stages in an air atmosphere to 1000-1500℃, kept at a constant temperature for 1-3 hours, quenched in ice water, dried at 70-90℃, ball-milled with media, dried and sieved to obtain glass powder.

10. A method for preparing an impact-reinforced structural ink according to any one of claims 1-9, characterized in that, Includes the following steps: The silica nanofiller, catalyst, dispersant and resin matrix are mixed and sonicated for 40-50 min to obtain a dispersion. Add the monomer microcapsules to the dispersion and stir at 300-500 rpm until homogeneous; Glass powder and pigments are added and ground to a fineness of ≤5μm to obtain an impact-resistant reinforced structural ink.