Adhesive for impregnated adhesive film paper and preparation method thereof

Abstract

The invention discloses an adhesive for impregnating adhesive film paper and a preparation method thereof, wherein the raw materials thereof include the following components: an aqueous polyurethane dispersion, a dispersant, a penetrant, a thickener, an anti-wear agent, and water, wherein the aqueous polyurethane dispersion contains a structural unit derived from diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine. The adhesive of the invention has the characteristics of being formaldehyde-free, pollution-resistant, easy to penetrate, having high bonding strength, and having good flexibility.

Description

Technical Field

[0001] The invention belongs to the field of adhesives, and in particular relates to an adhesive for impregnating adhesive film paper and a preparation method thereof. Background Art

[0002] Impregnated film paper, also known as "melamine" paper, is a printed decorative paper that is impregnated with amino resin and dried to a certain degree, with a certain resin content and volatile content. It can be glued to each other or to the artificial board substrate by hot pressing. With the rapid development and maturity of the decoration industry, people's requirements for environmental protection are gradually increasing, and people are afraid of "aldehyde". How to reduce free formaldehyde in decorative boards and prepare high-performance impregnated film paper has become a hot topic in the industry.

[0003] China's public patent CN113584936A introduces a UV coating for coating formaldehyde-free impregnated film paper, which has good curing effect. When used, it can quickly cure to form a mesh polymer surface layer under ultraviolet light. However, it sets the UV coating on the surface of the amino resin, which can expand the scope of use of the impregnated film paper and cannot fundamentally solve the problem of formaldehyde release. CN111411543 A introduces a solvent-resistant adhesive film paper adhesive and its preparation method. Its polyurethane emulsion has a small particle size, a small molecular weight, and a moderate viscosity, so that the impregnated adhesive can penetrate into the paper better, solving the problem of paper damage after ordinary resin adhesive impregnation, and at the same time increasing the amount of glue attached to the impregnated film paper. However, the solid content is low, the molecular weight is small, and there is a problem of low surface bonding strength. CN114293402A provides a non-toxic and smooth-surfaced formaldehyde-free hot-pressed impregnated decorative paper and its preparation method. It has the problems of long impregnation and curing time and low production efficiency.

[0004] Currently, urea-formaldehyde glue or melamine-formaldehyde glue is widely used in the impregnation glue industry. Relevant researchers are developing formaldehyde-free solutions, but they cannot achieve a balance in performance such as permeability, bonding strength and pollution resistance. The development of new adhesives has become a top priority for industry researchers. Summary of the invention

[0005] In view of the above problems existing in the prior art, the purpose of the present invention is to provide an adhesive for impregnated film paper and a preparation method thereof. The adhesive adopts a special aqueous polyurethane dispersion and has the characteristics of being formaldehyde-free, pollution-resistant, easy to penetrate, high bonding strength, and good flexibility.

[0006] To achieve the above-mentioned object of the invention, the technical solution of the present invention is as follows:

[0007] The present invention provides an adhesive for impregnating adhesive film paper, the adhesive comprising the following components in parts by weight:

[0008]

[0009] The aqueous polyurethane dispersion contains a structural unit derived from diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine (CAS: 214362-07-9), the structure of which is shown in Formula 1:

[0010]

[0011] In the aqueous polyurethane dispersion of the present invention, the mass content of the structural unit derived from the diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 0.5-5%, preferably 1-3.5%.

[0012] In the process of studying the adhesive for impregnating adhesive film paper, the present invention unexpectedly found that by adding diol N, N'-bis (2-hydroxyethyl) -N, N'-bis (trimethoxysilyl propyl) ethylenediamine to the raw materials during the preparation of the aqueous polyurethane dispersion, a polyol containing methoxysilane in the side chain is introduced into the main chain, which can improve the crosslinking density, increase the pollution resistance and wear resistance, and at the same time, the hydroxyl groups after the methoxy groups in the structure are hydrolyzed can also increase the adhesion to the substrate, thereby improving the bonding strength. In addition, the present invention also found that the use of polyether-modified siloxane with a specific structure as a penetrant can synergistically reduce the surface tension of the adhesive, make the adhesive easy to penetrate the substrate, reduce defects, and improve the surface bonding strength.

[0013] In the present invention, the aqueous polyurethane dispersion is an aqueous aliphatic polyurethane dispersion with a particle size of 50-150 nm and a solid content of 35-40%.

[0014] In the present invention, the aqueous polyurethane dispersion is prepared by reacting aliphatic diisocyanate, polyol, and optional chain extender, molecular weight control agent, hydrophilic monomer, etc., emulsifying with water, and removing solvent. The preparation process of the aqueous polyurethane dispersion is a method disclosed in the prior art. The present invention does not specifically limit the conditions such as the types of raw materials, raw material ratios, and operating parameters included in the specific preparation process. The technicians can prepare the aqueous polyurethane dispersion by any feasible method based on the prior art as needed; for example, the aqueous polyurethane dispersion can be prepared by referring to the methods disclosed in patents such as CN109337632A;

[0015] In some specific examples, the aliphatic diisocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, and toluene diisocyanate trimer, preferably hexamethylene diisocyanate and / or dicyclohexylmethane diisocyanate.

[0016] In some specific examples, the polyol is a polyol (preferably a diol) composition containing N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine, preferably a composition of N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine and polyethylene glycol-propylene glycol, polycaprolactone diol, polycarbonate diol, polypropylene glycol, polyethylene adipate diol, polybutylene adipate diol, polybutylene adipate diol, polyhexanediol adipate diol, polyneopentyl adipate diol, more preferably a composition of N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine and polybutylene adipate diol and / or polyhexanediol adipate diol;

[0017] Wherein, the average molecular weight of the poly(1,4-butylene adipate diol) and the poly(1,6-hexane adipate diol) is 500-3000 g / mol, preferably 1000-2000 g / mol;

[0018] Preferably, in the polyol composition, the polyol mass content of N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 2-15%, preferably 4-12%;

[0019] Preferably, the molar ratio of the aliphatic diisocyanate to the polyol is 1:1-4, preferably 1:1.3-2.6;

[0020] In some specific examples, the chain extender is selected from a sulfonic acid type hydrophilic chain extender containing active hydrogen, preferably one or more of 1,4-butanediol-2-sulfonate sodium 2-(2-aminoethyl)aminopropanesulfonate sodium, 2-(2-aminoethyl)aminoethanesulfonate sodium, and 1,2-dihydroxy-3-propanesulfonate sodium, more preferably 2-(2-aminoethyl)aminoethanesulfonate sodium;

[0021] Preferably, the molar ratio of the chain extender to the aliphatic diisocyanate is 1:20-40, preferably 1:27-38;

[0022] In some specific examples, the molecular weight control agent is selected from one or more of ethanolamine, diethanolamine, and triethanolamine, preferably diethanolamine;

[0023] Preferably, the molar ratio of the molecular weight control agent to the aliphatic diisocyanate is 1:8-40, preferably 1:13-29;

[0024] In some specific examples, the hydrophilic monomer is a component containing a polyethoxy chain segment that is reactive to isocyanate and monofunctional, and has a molecular weight of 500 to 3000 g / mol; preferably, it is a polyoxyalkylene ether containing at least one hydroxyl group, and the polymerization unit of the polyoxyalkylene ether is propylene oxide and / or ethylene oxide, more preferably ethylene oxide; preferably, the number of ethylene oxide units in each molecule of the polyoxyalkylene ether is 4 to 200, more preferably 12 to 75;

[0025] Preferably, the hydrophilic monomer is one or more of D-3403 of Tego Chemie, YmerTMN120 of Perstrop and MPEG1200 of Lotte, South Korea, more preferably MPEG1200 of Lotte;

[0026] Preferably, the molar ratio of the hydrophilic monomer to the aliphatic diisocyanate is 1:50-130, preferably 1:53-105;

[0027] In some specific examples, the reaction can be carried out with or without a catalyst, the catalyst is selected from organic bismuth, organic tin, etc., and the solvent is selected from acetone, butanone, etc., which are conventionally selected in the art, and there is no specific limitation on their usage.

[0028] In the present invention, the penetrant is polyether-modified siloxane, and the number of ethylene oxide units in each molecule is 2-20, and more preferably one or more of Silwet 618, RH-288, and Dow DC 193.

[0029] In the present invention, the thickener is selected from one or more of fumed silica, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose, carbomer, and lithium magnesium silicate, preferably lithium magnesium silicate.

[0030] In the present invention, the wear-resistant agent is selected from one or more of silicon dioxide suspension, aluminum oxide suspension and silicone resin emulsion, preferably silicone resin emulsion with a mass fraction of 45-55%.

[0031] Another object of the present invention is to provide a method for preparing the adhesive for impregnating adhesive film paper. The method comprises the following steps:

[0032] S1: Dispersing a thickener and part of water to prepare a pre-gel;

[0033] S2: Add the aqueous polyurethane dispersion into a dispersion kettle and stir (I), add a penetrant and stir (II), add an anti-wear agent and stir (III), add pregel and remaining water and stir (IV), adjust the viscosity, and prepare an adhesive for impregnating adhesive film paper.

[0034] In the present invention, the dispersion conditions in S1 are a rotation speed of 2000-3000 rpm and a time of 15-25 min.

[0035] In the present invention, the content of the thickener in the pre-gel described in S1 is 10-30wt%.

[0036] In the present invention, the stirring (I) of S2 has a rotation speed of 300-500 rpm; the stirring (II) has a rotation speed of 500-800 rpm and a time of 8-15 min; the stirring (III) has a rotation speed of 300-500 rpm and a time of 8-15 min; the stirring (IV) has a rotation speed of 500-800 rpm and a time of 10-25 min.

[0037] In the present invention, the viscosity of S2 is adjusted to 30-500 mPa·s.

[0038] Compared with the prior art, the positive effects of the present invention are:

[0039] 1) No formaldehyde is added to avoid releasing formaldehyde to pollute the air and reduce harm to the human body;

[0040] 2) Good pollution resistance: by adding polyols containing methoxysilane, the crosslinking density is increased and the pollution resistance is improved;

[0041] 3) Easy to penetrate, reduce the surface tension of the adhesive, make the adhesive easy to penetrate the substrate, reduce defects, increase surface bonding strength, and improve production efficiency. DETAILED DESCRIPTION

[0042] The embodiments of the present invention are further described below in conjunction with examples, but the present invention is not limited to the listed examples, and should also include any other known changes within the scope of the rights claimed by the present invention.

[0043] In the embodiments and comparative examples of the present invention, the sources of the main raw materials are as follows. Unless otherwise specified, other raw materials and reagents are purchased from common commercial sources:

[0044] PBA2000: polybutylene adipate, hydroxyl value 56 mgKOH / g, number average molecular weight 2000, Yantai Huada Chemical);

[0045] PHA2000: poly(1,6-hexanediol adipate), hydroxyl value 56 mgKOH / g, number average molecular weight 2000, Yantai Huada Chemical);

[0046] N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine: purity 95%, Shanghai Shiyang Chemical Co., Ltd.;

[0047] HMDI: dicyclohexylmethane diisocyanate: NCO content ≥ 31.8%, Wanhua Chemical Group Co., Ltd.

[0048] HDI: 1,6-hexamethylene diisocyanate, NCO content about 50%, Wanhua Chemical Group Co., Ltd.

[0049] MPEG: polyethylene glycol monomethyl ether, hydroxyl value 46.75 mgKOH / g, number average molecular weight 1200, functionality 1, Lotte, South Korea;

[0050] Diethanolamine: purity ≥98%, Dow Chemical;

[0051] Wear-resistant agent aluminum oxide: ZC-L10 Zhongchao shares;

[0052] Wear-resistant silicone resin emulsion: H9608, Hubei Longsheng Sihai;

[0053] Thickener lithium magnesium silicate WS3: density 2300-2600kg / m 3 , Leivos, Germany;

[0054] Penetrant Silwet 618: Purity ≥ 90%, Momentive High-Tech Materials;

[0055] RH288: Purity ≥ 90%, Zhejiang Runhe;

[0056] Penetrant DC 193: Purity ≥ 98%, Dow Chemical;

[0057] Thickener fumed silica: AEROSIL 200, purity ≥99%, Evonik, Germany.

[0058] Preparation Example 1 (Preparation of Aqueous Polyurethane Dispersion I):

[0059] 10g of dehydrated N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine, 200g of dehydrated polybutylene adipate PBA2000, 40g of dehydrated poly(1,6-hexanediol adipate), 45g of hexamethylene diisocyanate, 15g of dicyclohexylmethane diisocyanate, 95g of acetone and 7.5g of MPEG were added into a 1L four-necked round-bottom flask equipped with a nitrogen inlet and outlet, and the mixture was stirred at 85°C for 3h until the NCO% reached 4.85%. After cooling, 210g of acetone was added, and 4.3g of A-95 (2-(2-aminoethyl)-2-aminoethanesulfonic acid, 4.2g of IPDA and 5.2g of MPEG were added under stirring. A 50% diethanolamine aqueous solution was stirred for 10 minutes, and 615g of deionized water was added under rapid stirring to disperse. Acetone was then separated by distillation to obtain an aqueous polyurethane dispersion I. Its particle size was 65nm, and the solid content was 35.0wt%, of which the mass content of the structural unit derived from the diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine was 1.1%.

[0060] Preparation Example 2 (Preparation of Aqueous Polyurethane Dispersion II):

[0061] 30g of dehydrated N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine, 180g of dehydrated polybutylene adipate PBA2000, 40g of dehydrated poly(1,6-hexanediol adipate), 28g of hexamethylene diisocyanate, 40g of dicyclohexylmethane diisocyanate, 95g of acetone and 12g of MPEG were added into a 1L four-necked round-bottom flask equipped with a nitrogen inlet and outlet, and the mixture was stirred at 85°C for 3h until the NCO% reached 3.58%. After cooling, 220g of acetone was added, and 3.3g of A-95 (2-(2-aminoethyl)-2-aminoethanesulfonic acid, 2.4g of A 50% diethanolamine aqueous solution was stirred for 10 minutes, and 566g of deionized water was added under rapid stirring to disperse. Acetone was separated by distillation to obtain waterborne polyurethane dispersion II. The particle size was 83nm, the solid content was 39.5wt%, and the mass content of the structural unit derived from the diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine was 3.3%.

[0062] Preparation Example 3 (Preparation of Aqueous Polyurethane Dispersion III):

[0063] 20g of dehydrated N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilyl)ethylenediamine, 150g of dehydrated polybutylene adipate PBA2000, 80g of dehydrated poly1,6-hexanediol adipate diol, 35g of hexamethylene diisocyanate, 12g of dicyclohexylmethane diisocyanate, 100g of acetone, and 9.5g of MPEG were added to a 1L four-necked round-bottom flask equipped with a nitrogen inlet and outlet, and the mixture was stirred at 80°C for 3h until the NCO% reached 2.59%. After cooling, 210g of acetone was added, and 3.3g of A-95, 0.5g of IPDA, and 3.2g of a 50% diethanolamine aqueous solution were added under stirring, and the mixture was stirred for 10min. 547g of deionized water was added under rapid stirring for dispersion. Acetone was then separated by distillation to obtain waterborne polyurethane dispersion III. The particle size is 105 nm, the solid content is 37 wt %, and the mass content of the structural unit derived from the diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 2.3%.

[0064] The main properties of the embodiments of the present invention are tested by the following methods: (refer to GB / T 28995-2012, GB / T17657-2013, GB / T 15102-2017)

[0065] 1) Penetration time: immerse the base paper into the impregnating glue and record the time when the base paper is completely soaked;

[0066] 2) Glue amount: X = (m2-m1) / m1*100, where: X is the glue amount, m1 is the mass of the base paper, and m2 is the weight of the impregnated paper after drying;

[0067] 3) Surface bonding strength: according to the method specified in 4.16 of GB / T 17657-2013;

[0068] 4) Cracking resistance: according to the method specified in 4.36 of GB / T 17657-2013;

[0069] 5) Scratch resistance: According to the method specified in 4.39 of GB / T 17657-2013, the load is 1.50N;

[0070] 6) Wear resistance: according to the method specified in 4.44 of GB / T 17657-2013;

[0071] 7) Folding fracture angle: The maximum angle at which the impregnated film paper does not break when it is bent is recorded as the folding fracture angle;

[0072] 8) Formaldehyde emission: according to the method specified in 4.59 of GB / T 17657-2013;

[0073] 9) Pollution resistance: According to the method specified in 4.41 of GB / T 17657-2013;

[0074] The main equipment information used in each embodiment and comparative example of the present invention is as follows:

[0075] 1) Multifunctional disperser: EDS1000, Shanghai Pushen Chemical Machinery Co., Ltd.;

[0076] 2) Universal testing machine: AI-7000M, high-speed rail testing;

[0077] 3) Scratch tester: HY-IV, Shanghai Modern Environmental Engineering Technology Co., Ltd.;

[0078] 4) Blast drying oven: GT-7024-EL, high-speed rail testing;

[0079] 5) Constant temperature and humidity chamber: GPL-2, Espec Experimental Instruments (Guangdong) Co., Ltd.;

[0080] 6) TABER Abrasion Tester: HY-768, Hengyu Instrument Co., Ltd., Taiwan, China.

[0081] Example 1

[0082] The adhesive is prepared from the following raw materials in parts by weight:

[0083] Waterborne polyurethane dispersion Ⅰ: 68.0g,

[0084] Silwet 618: 2.0g,

[0085] WS3:1.0g,

[0086] H9608: 9g,

[0087] Water: 20g.

[0088] Preparation of adhesive for impregnated film paper:

[0089] S1: Add thickener WS3 and deionized water into a high-speed disperser in sequence, at 2500 rpm, and disperse for 20 min to prepare a pre-gel with a concentration of 20 wt% for later use;

[0090] S2: Add the aqueous polyurethane dispersion I into the dispersion kettle, and stir the shaft at a speed of 400 rpm; add the penetrant Silwet 618, stir for 15 min, and stir the shaft at a speed of 600 rpm; add the wear agent H9608, stir for 12 min, and stir the shaft at a speed of 500 rpm; finally, add the remaining deionized water and pregel, stir for 15 min, and stir the shaft at a speed of 650 rpm, and adjust the viscosity to 400 mPa·s to prepare an adhesive for impregnating adhesive film paper.

[0091] Example 2

[0092] The adhesive is prepared from the following raw materials in parts by weight:

[0093] Waterborne polyurethane dispersion II: 60g,

[0094] RH288: 1g,

[0095] Sodium carboxymethyl cellulose: 0.2g,

[0096] H9608:15.0g,

[0097] Water: 24.0g.

[0098] Preparation of adhesive for impregnated film paper:

[0099] S1: Add the thickener sodium carboxymethyl cellulose and deionized water into a high-speed disperser in sequence, at 3000 rpm, and disperse for 15 min to prepare a pre-gel with a concentration of 15 wt% for later use;

[0100] S2: Add waterborne polyurethane dispersion II into the dispersion kettle, and stir the shaft at a speed of 300 rpm; add penetrant RH288, stir for 10 min, and stir the shaft at a speed of 400 rpm; add wear-resistant agent H9608, stir for 15 min, and stir the shaft at a speed of 500 rpm; finally, add the remaining deionized water and pregel, stir for 10 min, and stir the shaft at a speed of 800 rpm, and adjust the viscosity to 53 mPa·s to prepare an adhesive for impregnating adhesive film paper.

[0101] Example 3

[0102] The adhesive is prepared from the following raw materials in parts by weight:

[0103] Waterborne polyurethane dispersion III: 50.0g,

[0104] DC 193: 3.0g,

[0105] WS3: 2g,

[0106] ZC-L10: 5.0g,

[0107] Water: 40.0g.

[0108] Preparation of adhesive for impregnated film paper:

[0109] S1: Add thickener WS3 and deionized water into a high-speed disperser in sequence, at 3000 rpm, and disperse for 25 min to prepare a pre-gel with a concentration of 30 wt% for later use;

[0110] S2: Add waterborne polyurethane dispersion III into the dispersion kettle, and stir the shaft at a speed of 400 rpm; add penetrant DC193, stir for 8 min, and stir the shaft at a speed of 500 rpm; add wear agent ZC-L10, stir for 8 min, and stir the shaft at a speed of 800 rpm; finally, add the remaining deionized water and pregel, stir for 25 min, and stir the shaft at a speed of 500 rpm, and adjust the viscosity to 350 mPa·s to prepare an adhesive for impregnating adhesive film paper.

[0111] Comparative Example 1

[0112] Referring to Example 3, the only difference is that: N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine was not used in the preparation of aqueous polyurethane dispersion III, and other parameters and operations remained unchanged to prepare an adhesive.

[0113] Comparative Example 2

[0114] Referring to Example 3, the only difference is that when preparing the aqueous polyurethane dispersion III, N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is replaced with double-terminal carbon hydroxyl-terminated silicone oil (Hangzhou Chongyao Technology Development Co., Ltd., SL7520), and other parameters and operations remain unchanged to prepare an adhesive for use.

[0115] Comparative Example 3

[0116] Referring to Example 3, the only difference is that when preparing the aqueous polyurethane dispersion III, N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is replaced with trimethoxy-terminated polydimethylsiloxane (Ningbo Runhe High-tech Materials Technology Co., Ltd., RH-FW1K), and other parameters and operations remain unchanged to prepare an adhesive for use.

[0117] Comparative Example 4

[0118] Referring to Example 1, the only difference is that no penetrant is used in the preparation process of the adhesive, and other parameters and operations remain unchanged to prepare an adhesive for use.

[0119] Comparative Example 5

[0120] Referring to Example 1, the only difference is that no wear-resistant agent is used in the preparation process of the adhesive, and other parameters and operations remain unchanged to prepare an adhesive for use.

[0121] Comparative Example 6

[0122] Referring to Example 1, the only difference is that no thickener is used in the preparation process of the adhesive, and other parameters and operations remain unchanged to prepare an adhesive for use.

[0123] Comparative Example 7

[0124] This comparative example is melamine impregnated glue

[0125] The melamine impregnated adhesive is prepared from the following raw materials in parts by weight:

[0126] Water-based melamine resin dispersion: 98g,

[0127] German Woshi 740: 0.5g,

[0128] Dioctyl maleate sodium sulfonate: 1.5g.

[0129] Preparation of aqueous melamine resin dispersion in this comparative example:

[0130] Accurately weigh each component according to the ratio of the glue base material, add water and formaldehyde solution into the reactor, stir evenly, then add melamine powder, start the stirrer to stir at a speed of (1200 revolutions per minute), raise the temperature to 100°C, and react the mixed solution for 100 minutes under stirring. When the water-soluble ratio of the liquid is 1:3, add caustic soda into the reactor to adjust the pH value of the mixed liquid to 9.0, cool the glue base mixed solution to 45°C, add diethylene glycol, stir evenly and set aside;

[0131] Prepared according to the following raw materials in parts by weight:

[0132] 55kg of water, 120kg of 34% formaldehyde aqueous solution by weight, 90kg of melamine powder, and 18kg of diethylene glycol.

[0133] The base paper was impregnated with the adhesive prepared in the embodiment and the comparative example, and dried at 130°C to obtain impregnated adhesive film paper; the impregnated adhesive film paper was hot pressed to the surface of the artificial board under the conditions of 8MPa, 150°C, and 1min to obtain the decorative paper veneer artificial board. The impregnated adhesive prepared in the above embodiment was tested according to the national standards GB / T 28995-2012, GB / T 17657-2013, and GB / T 15102-2017, and the test results are shown in Table 1.

[0134] Table 1 Performance test results of various embodiments and comparative examples

[0135]

[0136]

[0137] Finally, it should be noted that the above embodiments are only used to describe the preferred implementation methods of the present invention, rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that various modifications and improvements made by modifying or equivalently replacing the technical solution of the present invention should fall within the protection scope determined by the claims of the present invention.

Claims

1. An adhesive for impregnating adhesive film paper, characterized in that: The adhesive comprises the following components in parts by weight: The aqueous polyurethane dispersion contains structural units derived from diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine.

2. The adhesive according to claim 1, characterized in that The adhesive comprises the following components in parts by weight:

3. The adhesive according to claim 1, characterized in that In the aqueous polyurethane dispersion, the mass content of the structural unit derived from the diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 0.5-5%.

4. The adhesive according to claim 3, characterized in that The mass content of the structural unit derived from the diol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 1-3.5%.

5. The adhesive according to claim 1, characterized in that The aqueous polyurethane dispersion is an aqueous aliphatic polyurethane dispersion with a particle size of 50-150 nm and a solid content of 35-40%.

6. The adhesive according to claim 1, characterized in that: The waterborne polyurethane dispersion is prepared by reacting aliphatic diisocyanate, polyol, chain extender, molecular weight control agent and hydrophilic monomer, adding water for emulsification and removing solvent.

7. The adhesive according to claim 6, characterized in that: The aliphatic diisocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, and toluene diisocyanate trimer; The polyol is a polyol composition comprising N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine; The chain extender is selected from a sulfonic acid type hydrophilic chain extender containing active hydrogen; The molecular weight control agent is selected from one or more of ethanolamine, diethanolamine, and triethanolamine; The hydrophilic monomer is a component reactive to isocyanate and monofunctional and containing a polyethoxy chain segment, and has a molecular weight of 500 to 3000 g / mol.

8. The adhesive according to claim 7, characterized in that The polyol is a composition of one or more of N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine and polyethylene glycol-propylene glycol, polycaprolactone diol, polycarbonate diol, polypropylene glycol, polyethylene adipate diol, polybutylene adipate diol, polyhexanediol adipate diol, and polyneopentyl adipate diol.

9. The adhesive according to claim 8, characterized in that: The average molecular weight of the poly(1,4-butylene adipate diol) and the poly(1,6-hexane adipate diol) is 500 to 3000 g / mol.

10. The adhesive according to claim 9, characterized in that The average molecular weight of the poly(1,4-butylene adipate diol) and the poly(1,6-hexane adipate diol) is 1000-2000 g / mol.

11. The adhesive according to claim 8, characterized in that: In the polyol composition, the mass content of the polyol N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 2-15%.

12. The adhesive according to claim 11, characterized in that The polyol mass content of the N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine is 4-12%.

13. The adhesive according to claim 7, characterized in that: The polyol is a diol composition comprising N,N'-bis(2-hydroxyethyl)-N,N'-bis(trimethoxysilylpropyl)ethylenediamine.

14. The adhesive according to claim 7, characterized in that: The chain extender is selected from one or more of 1,4-butanediol-2-sulfonate sodium, 2-(2-aminoethyl)aminopropanesulfonate sodium, 2-(2-aminoethyl)aminoethanesulfonate sodium, and 1,2-dihydroxy-3-propanesulfonate sodium.

15. The adhesive according to claim 7, characterized in that: The hydrophilic monomer is a polyoxyalkylene ether containing at least one hydroxyl group, and the polymerized unit of the polyoxyalkylene ether is propylene oxide and / or ethylene oxide.

16. The adhesive according to claim 15, characterized in that The number of ethylene oxide units in each molecule of the polyoxyalkylene ether is 4 to 200.

17. The adhesive according to claim 16, characterized in that The number of ethylene oxide units in each molecule of the polyoxyalkylene ether is 12 to 75.

18. The adhesive according to claim 6, characterized in that: The hydrophilic monomer is one or more of D-3403 from Tego Chemie, YmerTM N120 from Perstrop, and MPEG1200 from Lotte, South Korea.

19. The adhesive according to claim 1, characterized in that: The penetrant is polyether-modified siloxane, and the number of ethylene oxide units in each molecule is 2-20.

20. The adhesive according to claim 1, characterized in that The penetrant is one or more of Silwet 618, RH-288, and Dow DC 193.

21. The adhesive according to claim 1, characterized in that The thickener is selected from one or more of fumed silica, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose, carbomer, and lithium magnesium silicate.

22. The adhesive according to claim 1, characterized in that The wear-resistant agent is selected from one or more of silicon dioxide suspension, aluminum oxide suspension and silicone resin emulsion.

23. The adhesive according to claim 22, characterized in that The anti-wear agent is selected from 45-55% by mass of organic silicone resin emulsion.

24. A method for preparing the adhesive for impregnated adhesive film paper according to any one of claims 1 to 23, characterized in that: The following steps are included: S1: Dispersing a thickener and part of water to form a pre-gel; S2: Add the aqueous polyurethane dispersion into a dispersion kettle and stir (I), add a penetrant and stir (II), add an anti-wear agent and stir (III), add pregel and remaining water and stir (IV), adjust the viscosity, and prepare an adhesive for impregnating adhesive film paper.

25. The preparation method according to claim 24, characterized in that: The dispersion conditions in S1 are a rotation speed of 2000-3000 rpm and a time of 15-25 min; The content of thickener in the pre-gel described in S1 is 10-30wt%; S2: the stirring (I) has a rotation speed of 300-500 rpm; the stirring (II) has a rotation speed of 500-800 rpm and a time of 8-15 min; the stirring (III) has a rotation speed of 300-500 rpm and a time of 8-15 min; the stirring (IV) has a rotation speed of 500-800 rpm and a time of 10-25 min; S2 The viscosity is adjusted to 30-500 mPa·s.

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