Rose essential oil water-based bi-component electrostatic spraying varnish primer and preparation method thereof

Abstract

The invention discloses a rose essential oil water-based bi-component electrostatic spraying varnish primer and a preparation method thereof. The rose essential oil water-based bi-component electrostatic spraying varnish primer comprises a component A and a component B, the component A is prepared from the following components in parts by weight: 30 to 40 parts of waterborne hydroxyl polyurethane emulsion; 15 to 25 parts by weight of deionized water; 5 to 10 parts by weight of a modified chitosan / nano silicon dioxide compound; 0.5 to 0.8 part by weight of a defoaming agent; 1-2 parts by weight of a dispersant; 0.5-1 part by weight of a leveling agent; 0.5-1 part by weight of a preservative; 0.5-1 part by weight of rose essential oil; the component B is prepared from 10 to 15 parts by weight of polyisocyanate; and 3-5 parts by weight of a coalescing agent. According to the invention, the modified nano silicon dioxide is adopted, and a compact three-dimensional network structure is formed through modification of chitosan and crosslinking of ammonium polyphosphate, so that permeation of the rose essential oil is effectively inhibited, and the lasting release effect of the rose essential oil in the coating is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, in particular to a rose essential oil water-based two-component electrostatic spray varnish primer and a preparation method thereof. Background Art

[0002] With the development of coating technology, water-based coatings, as an environmentally friendly material, have gradually attracted widespread attention and application due to their advantages such as low VOC (volatile organic compound) emissions, non-toxicity, and easy operation. As an important branch, water-based two-component coating systems are usually composed of resins, curing agents, pigments, additives, etc. Rose essential oil is often added to certain coatings due to its unique aroma and excellent biological activity to improve the functionality and added value of the coating. In addition to giving the coating aromatic functions, rose essential oil also has antioxidant and antibacterial properties, making it suitable for the development of high-end coatings.

[0003] However, the varnish primer needs to penetrate into the substrate to provide good adhesion. However, this may also cause some essential oils to penetrate into the substrate along with the primer, thereby reducing the amount of essential oils on the surface and affecting the sustained release effect. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the present invention provides a rose essential oil water-based two-component electrostatic spray varnish primer and a preparation method thereof, which solves the problems raised in the above-mentioned background technology.

[0006] (II) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A rose essential oil water-based two-component electrostatic spray varnish primer, characterized in that the rose essential oil water-based two-component electrostatic spray varnish primer comprises component A and component B;

[0009] The A group is composed of:

[0010] Water-based hydroxy polyurethane emulsion: 30-40 parts by weight

[0011] Deionized water: 15-25 parts by weight

[0012] Modified chitosan / nano-silicon dioxide composite: 5-10 parts by weight

[0013] Dispersant: 1-2 parts by weight

[0014] Leveling agent: 0.5-1 parts by weight

[0015] Defoamer: 0.5-0.8 parts by weight

[0016] Preservatives: 0.5-1 parts by weight

[0017] Rose essential oil: 0.5-1 parts by weight

[0018] Group B is composed of:

[0019] 10-15 parts by weight of polyisocyanate;

[0020] 3-5 parts by weight of film-forming aid.

[0021] The modified chitosan / nano-silicon dioxide composite is prepared by the following steps:

[0022] Dissolve 100 parts by weight of chitosan in an appropriate amount of water to prepare a solution with a concentration of 1% to 3%;

[0023] Slowly add 5-30 parts by weight of maleic acid, stir evenly, select the reaction temperature to be 60-80°C, the reaction time to be 2-4 hours, and carry out acylation reaction;

[0024] After the reaction is completed, the mixture is cooled and precipitated and washed with water to remove unreacted substances, thereby obtaining modified chitosan;

[0025] Disperse 80-120 parts by weight of nano-silicon dioxide with an appropriate amount of water, and use ultrasonic treatment to ensure uniform dispersion to obtain dispersed nano-silicon dioxide;

[0026] The modified chitosan is mixed with the dispersed nano-silicon dioxide, and stirred evenly to form a chitosan / nano-silicon dioxide composite material;

[0027] Mixing 5-30 parts by weight of ammonium polyphosphate with 100 parts by weight of chitosan / nano-silicon dioxide composite material, stirring evenly to obtain a mixture;

[0028] The mixture is transferred to a container, heated to 80-100° C., and reacted for 2-4 hours to promote the cross-linking reaction to obtain a modified chitosan / nano-silicon dioxide composite.

[0029] The hydroxyl content in the aqueous hydroxyl polyurethane emulsion is 1.5% to 6.5%.

[0030] The solid content of the aqueous hydroxyl polyurethane emulsion is 30-40wt%, and the viscosity at 25 degrees Celsius is 1000-10000mPa·s;

[0031] The polyisocyanate comprises:

[0032] HDI trimer 10-30 parts by weight

[0033] Isophorone diisocyanate 5-10 parts by weight

[0034] 5-10 parts by weight of dicyclohexylmethane diisocyanate.

[0035] A method for preparing a rose essential oil water-based two-component electrostatic spray varnish primer, wherein the rose essential oil water-based two-component electrostatic spray varnish primer comprises a component A and a component B;

[0036] The A group is composed of:

[0037] Water-based hydroxy polyurethane emulsion: 30-40 parts by weight

[0038] Deionized water: 15-25 parts by weight

[0039] Modified chitosan / nano-silicon dioxide composite: 5-10 parts by weight

[0040] Dispersant: 1-2 parts by weight

[0041] Leveling agent: 0.5-1 parts by weight

[0042] Defoamer: 0.5-0.8 parts by weight

[0043] Preservatives: 0.5-1 parts by weight

[0044] Rose essential oil: 0.5-1 parts by weight

[0045] Group B is composed of:

[0046] 10-15 parts by weight of polyisocyanate;

[0047] Propylene glycol butyl ether 3-5 parts by weight.

[0048] The A and B components are mixed evenly and packaged separately to obtain a rose essential oil water-based two-component electrostatic spray varnish primer.

[0049] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0050] The present invention adopts modified nano silicon dioxide, forms a dense three-dimensional network structure through the modification of chitosan and the cross-linking of ammonium polyphosphate, effectively inhibits the penetration of rose essential oil into the substrate, and ensures the lasting release effect of rose essential oil in the coating. DETAILED DESCRIPTION

[0051] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] In the following examples and comparative examples:

[0053] Hydroxyl-containing waterborne polyurethane dispersion:

[0054] Covestro's Bayhydrol UH 2592 has a hydroxyl content of 2.1%, a solid content of 45%, and a viscosity of 500 mPa·s.

[0055] HDI trimer VPLS2151 (Covestro)

[0056] IPDI (isophorone diisocyanate) T 1890 (Evonik)

[0057] Dicyclohexylmethane diisocyanate: Desmodur W H12MDI

[0058] The recipe is as follows:

[0059] Group A is composed of:

[0060] Water-based hydroxy polyurethane emulsion: 30-40 parts by weight

[0061] Deionized water: 15-25 parts by weight

[0062] Modified chitosan / nano-silicon dioxide composite: 5-10 parts by weight

[0063] Dispersant: 1-2 parts by weight

[0064] Leveling agent: 0.5-1 parts by weight

[0065] Defoamer: 0.5-0.8 parts by weight

[0066] Preservatives: 0.5-1 parts by weight

[0067] Rose essential oil: 0.5-1 parts by weight

[0068] Group B is composed of:

[0069] 10-15 parts by weight of polyisocyanate;

[0070] 3-5 parts by weight of film-forming aid.

[0071] The modified chitosan / nano-silicon dioxide composite is prepared by the following steps:

[0072] Dissolve 100 parts by weight of chitosan in an appropriate amount of water to prepare a solution with a concentration of 2%;

[0073] Slowly add 20 parts by weight of maleic acid, stir evenly, select the reaction temperature to be 80°C, the reaction time to be 3 hours, and carry out ether acylation reaction;

[0074] After the reaction is completed, the mixture is cooled and precipitated and washed with water to remove unreacted substances, thereby obtaining modified chitosan;

[0075] Disperse 100 parts by weight of nano-silicon dioxide with an appropriate amount of water, and use ultrasonic treatment to ensure uniform dispersion to obtain dispersed nano-silicon dioxide;

[0076] The modified chitosan is mixed with the dispersed nano-silicon dioxide, and stirred evenly to form a chitosan / nano-silicon dioxide composite material;

[0077] Mix 20 parts by weight of ammonium polyphosphate and 100 parts by weight of chitosan / nano-silicon dioxide composite material, and stir evenly to obtain a mixture;

[0078] The mixture was transferred to a container, heated to 80° C., and reacted for 2 hours to promote the cross-linking reaction to obtain a modified chitosan / nano-silica composite.

[0079] Polyisocyanates include:

[0080] HDI trimer 20 parts by weight

[0081] Isophorone diisocyanate 10 parts by weight

[0082] 10 parts by weight of dicyclohexylmethane diisocyanate.

[0083] Example 1

[0084] Group A is composed of:

[0085] Water-based hydroxy polyurethane emulsion: 40 parts by weight

[0086] Deionized water: 15 parts by weight

[0087] Modified chitosan / nano-silicon dioxide composite: 8 parts by weight

[0088] Dispersant: 2 parts by weight

[0089] Leveling agent: 1 part by weight

[0090] Defoamer: 0.8 parts by weight

[0091] Preservative: 1 part by weight

[0092] Rose essential oil: 1 part by weight

[0093] Group B is composed of:

[0094] 15 parts by weight of polyisocyanate;

[0095] Propylene glycol butyl ether agent 5 parts by weight.

[0096] The modified chitosan / nano-silicon dioxide composite is prepared by the aforementioned method.

[0097] Example 2

[0098] Water-based hydroxy polyurethane emulsion: 40 parts by weight

[0099] Deionized water: 15 parts by weight

[0100] Modified chitosan / nano-silica composite: 10 parts by weight

[0101] Dispersant: 2 parts by weight

[0102] Leveling agent: 1 part by weight

[0103] Defoamer: 0.8 parts by weight

[0104] Preservative: 1 part by weight

[0105] Rose essential oil: 1 part by weight

[0106] Group B is composed of:

[0107] 15 parts by weight of polyisocyanate;

[0108] Propylene glycol butyl ether agent 5 parts by weight.

[0109] The modified chitosan / nano-silicon dioxide composite is prepared by the aforementioned method.

[0110] Comparative Example 1

[0111] The same as Example 1, but the same weight of n-octanol was used instead of maleic acid for modification.

[0112] Comparative Example 2

[0113] The same as Example 1, but the same weight of octanoic acid was used instead of maleic acid for modification.

[0114] Comparative Example 3

[0115] The same as Example 1, but using the same weight of chitosan / nano-silicon dioxide composite material, without ammonium polyphosphate cross-linking.

[0116] Comparative Example 4

[0117] Same as Example 1, but using the same weight of glutaraldehyde instead of ammonium polyphosphate for cross-linking.

[0118] Comparative Example 5

[0119] The same as Example 1, but using the same weight of polyvinyl alcohol instead of ammonium polyphosphate for cross-linking.

[0120] Penetration Testing

[0121] Substrate treatment:

[0122] Clean the surface of the pine board substrate to remove impurities and oil stains.

[0123] Dry the pine board substrate to ensure that there is no moisture on the surface.

[0124] The coatings of the above-mentioned embodiments and comparative examples are uniformly applied on the surface of the substrate by electrostatic spraying. The coating thickness is controlled to ensure consistency (the thickness is 100 microns, with an error of plus or minus 2 microns). Natural drying is performed at room temperature or heat drying is performed according to the coating instructions. Numbers and relevant information (such as substrate type, coating thickness) are marked on each sample. Place for 30 days. The coating on the surface of the substrate that has been placed for 30 days is removed until the complete substrate is exposed, and a 1cm*1cm block is cut out of the middle of the substrate. The 1cm*1cm block is completely immersed in distilled water, ultrasonically treated for 2 hours, and the content of essential oils in the water is analyzed by GC-MS.

[0125] Example Essential oil content Example 1 8.4ppm Example 2 9.4ppm Comparative Example 1 20.4ppm Comparative Example 2 15.0ppm Comparative Example 3 89.2ppm Comparative Example 4 19.8ppm Comparative Example 5 21.0ppm

[0126] It can be seen that by combining chitosan with nano-silica, a new type of coating additive is formed, which uses the network structure of nano-silica to inhibit the penetration of essential oils. Chitosan is modified by acylation reaction to make it have better lipophilicity and cross-linking ability. With this modification method, the network structure of nano-silica is more dense. Compared with other cross-linking substances, ammonium polyphosphate is more able to promote the cross-linking of chitosan / nano-silica composite materials to form a dense three-dimensional network structure.

[0127] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A rose essential oil water-based two-component electrostatic spray varnish primer, characterized in that: The rose essential oil water-based two-component electrostatic spray varnish primer comprises component A and component B; The A group is composed of: Water-based hydroxy polyurethane emulsion: 30-40 parts by weight Deionized water: 15-25 parts by weight Modified chitosan / nano-silicon dioxide composite: 5-10 parts by weight Dispersant: 1-2 parts by weight Leveling agent: 0.5-1 parts by weight preservative: 0.5-1 parts by weight Defoamer: 0.5-0.8 parts by weight Rose essential oil: 0.5-1 parts by weight Group B is composed of: 10-15 parts by weight of polyisocyanate; 3-5 parts by weight of film-forming aid.

2. A rose essential oil water-based two-component electrostatic spray varnish primer according to claim 1, characterized in that: The modified chitosan / nano-silicon dioxide composite is prepared by the following steps: Dissolve 100 parts by weight of chitosan in an appropriate amount of water to prepare a solution with a concentration of 1% to 3%; Slowly add 5-30 parts by weight of maleic acid, stir evenly, select the reaction temperature to be 60-80°C, the reaction time to be 2-4 hours, and carry out acylation reaction; After the reaction is completed, the mixture is cooled and precipitated and washed with water to remove unreacted substances, thereby obtaining modified chitosan; Disperse 80-120 parts by weight of nano-silicon dioxide with an appropriate amount of water, and use ultrasonic treatment to ensure uniform dispersion to obtain dispersed nano-silicon dioxide; The modified chitosan is mixed with the dispersed nano-silicon dioxide, and stirred evenly to form a chitosan / nano-silicon dioxide composite material; Mixing 5-30 parts by weight of ammonium polyphosphate with 100 parts by weight of chitosan / nano-silicon dioxide composite material, stirring evenly to obtain a mixture; The mixture is transferred to a container, heated to 80-100° C., and reacted for 2-4 hours to promote the cross-linking reaction to obtain a modified chitosan / nano-silicon dioxide composite.

3. A rose essential oil water-based two-component electrostatic spray varnish primer according to claim 1, characterized in that: The hydroxyl content in the aqueous hydroxyl polyurethane emulsion is 1.5% to 6.5%.

4. A rose essential oil water-based two-component electrostatic spray varnish primer according to claim 1, characterized in that: The solid content of the aqueous hydroxyl polyurethane emulsion is 30-40 wt %, and the viscosity at 25 degrees Celsius is 1000-10000 mPa·s.

5. The rose essential oil water-based two-component electrostatic spray varnish primer according to claim 1, characterized in that: The polyisocyanate comprises: HDI trimer 10-30 parts by weight Isophorone diisocyanate 5-10 parts by weight 5-10 parts by weight of dicyclohexylmethane diisocyanate.

6. A method for preparing a rose essential oil water-based two-component electrostatic spray varnish primer, characterized in that: The rose essential oil water-based two-component electrostatic spray varnish primer comprises component A and component B; The A group is composed of: Water-based hydroxy polyurethane emulsion: 30-40 parts by weight Deionized water: 15-25 parts by weight Modified chitosan / nano-silicon dioxide composite: 5-10 parts by weight Dispersant: 1-2 parts by weight Leveling agent: 0.5-1 parts by weight Defoamer: 0.5-0.8 parts by weight Preservatives: 0.5-1 parts by weight Rose essential oil: 0.5-1 parts by weight Group B is composed of: 10-15 parts by weight of polyisocyanate; 3-5 parts by weight of film-forming aid; The A and B components are mixed evenly and packaged separately to obtain a rose essential oil water-based two-component electrostatic spray varnish primer.