Glue for printing and compounding polyethylene protective film as well as preparation method and application of glue

Abstract

The invention discloses glue for printing and compounding a polyethylene protective film as well as a preparation method and application of the glue, and belongs to the technical field of water-based functional polymer materials. According to the invention, a traditional polyacrylate emulsion polymerization process is adopted, and on the basis of regulating and optimizing the types and proportions of acrylate soft, hard and functional monomers, a characteristic cross-linking monomer with a high-cohesive-force component is introduced, so that the adhesive property of the polyacrylate adhesive is remarkably improved; and meanwhile, when being used as glue for printing and compounding a polyethylene protective film, the adhesive has excellent bonding and compounding efficiency and tear resistance. The glue is applied to printing compounding of protective films of aluminum profiles, aluminum-plastic panels, carbon profiles and plastic profiles. And the glue for printing and compounding the polyethylene protective film takes water as a solvent and does not relate to other organic solvents, so that the glue is green and environment-friendly and has a wide application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of water-based functional polymer materials, and in particular relates to glue for printing and compounding of polyethylene protective films and a preparation method and application thereof. Background Art

[0002] During the transportation, storage, processing and assembly of goods, their surfaces usually need to be protected. One of the common methods is to attach a layer of surface protection film, protective tape or pressure-sensitive protective film, referred to as protective film, to the surface of the protected object. The protective film is generally a polymer film obtained by processes such as blown film molding of plastic masterbatches such as polymer plastics such as polyethylene (PE), polypropylene (PP) and polyester (PET), and then prepared by processes such as coating pressure-sensitive adhesive, drying, winding and cutting. Among them, the surface of the protective film usually needs to be printed and coated with certain graphics, trademarks and special logos. If it is not protected, it is very easy to be damaged during use and affect the use effect. In order to effectively protect the ink pattern layer, it is necessary to paste a layer of transparent plastic film on its surface. Therefore, the glue used for pasting and compounding the two layers of polymer films in the protective film is usually called plastic-plastic composite film glue for protective film, also known as (plastic-plastic) composite glue, or composite glue for short.

[0003] Protective film has become one of the most popular flexible packaging materials due to its good flexibility, good foldability and easy use. Therefore, the composite adhesive used in its preparation process must also have excellent flexibility and strong bonding performance. Only with high bonding strength can the composite effect be good and the composite film will not crack. At present, although there are many types of composite adhesives, for composite adhesives for protective films, the vast majority of them on the market are polyacrylate emulsion pressure-sensitive adhesives, and there are only a handful of composite adhesive products with excellent bonding and composite performance.

[0004] At present, the commercially available pressure-sensitive adhesive for protective film is mainly water-based polyacrylate emulsion, which uses water as the dispersion medium, has obvious cost advantages, does not involve organic solvents, is environmentally friendly, has good controllability of polymer process, and is easy to prepare low-viscosity pressure-sensitive adhesives with high solid content and large relative molecular weight. At the same time, it also has significant disadvantages, such as long drying time due to the use of water as the solvent, relatively poor product performance, low peel strength and adhesion, and the need to improve the bonding strength and comprehensive performance, so it cannot fully meet market demand.

[0005] Chinese patent application CN202310820228.4 discloses a single-component water-based acrylic emulsion laminating adhesive with a core-shell structure. Although it has excellent bonding properties, peelability and water resistance, the amount of glue used for its coating is large, and the 180o peel strength is only 650gf / 25mm. The relevant performance, testing and indicators of the composite adhesive are not involved. Chinese patent application CN202311768440.7 discloses a polyurethane-based laminating adhesive, a laminating preparation method and a thin film laminating. The invention shows that after coating the laminating adhesive, it has good adhesion, but the polyurethane laminating adhesive not only has a complex preparation process, but also has a high price, which is not conducive to promotion and application. In the early stage, we introduced hydrogenated rosin or hydrogenated epoxy resin functional monomers on the basis of acrylate monomers through polymer structure design and process optimization in the invention patent CN202311556629.X, which effectively improved and improved its application in the field of low surface energy plastic composite. However, the overall water resistance performance has not been improved, and the bonding performance, peeling performance and economic performance are still to be improved. Therefore, the present invention continues to focus on the field of low surface energy plastic-plastic composite, especially the composite adhesive involved in the polyethylene protective film printing composite process, to further improve its composite effect and reduce costs. Summary of the invention

[0006] In order to solve the deficiencies of the prior art, the primary purpose of the present invention is to provide a polyethylene protective film printing and compounding glue, and the present invention also provides a preparation method of the polyethylene protective film printing and compounding glue.

[0007] Another object of the present invention is to provide an application of glue for printing and compounding polyethylene protective films, which is applied to printing and compounding polyethylene protective films in the fields of aluminum profiles, aluminum-plastic panels, carbon profiles, and plastic profiles.

[0008] In order to achieve the above technical purpose, the present invention designs and prepares a polyethylene protective film printing composite glue based on the polymer molecular structure design and adhesive bonding mechanism.

[0009] Specifically, the technical solution adopted by the present invention is: a polyethylene protective film printing composite glue is prepared by regulating acrylic (ester) soft, hard, functional monomers and cross-linking monomers through emulsion polymerization to obtain a polyethylene protective film printing composite glue. The results show that the polyethylene protective film printing composite glue has excellent bonding and tearing resistance, which is completely superior to similar products on the market, and thus has broad application prospects.

[0010] The technical solution adopted by the present invention is:

[0011] A glue for printing and laminating polyethylene protective film, comprising the following raw materials in parts by weight: 20.0 - 30.0 parts of acrylate soft monomer component, 5.0 - 8.0 parts of acrylate hard monomer component, 5.0 - 10.0 parts of acrylate functional monomer component, 2.0 - 5.0 parts of special crosslinking monomer component, 0.5 - 1.5 parts of emulsifier, 0.25 - 0.5 parts of initiator, and 40.0 - 60.0 parts of deionized water.

[0012] Preferably, the glue for printing and laminating polyethylene protective film comprises the following raw materials in parts by weight: 30.0 parts of acrylate soft monomer component, 5 parts of acrylate hard monomer component, 8 parts of acrylate functional monomer component, 2 parts of special crosslinking monomer component, 1.5 parts of emulsifier, 0.25 parts of initiator, and 60.0 parts of deionized water.

[0013] Preferably, the acrylate soft monomer component is one or more of butyl acrylate, isooctyl acrylate, hexadecyl acrylate, octadecyl acrylate.

[0014] More preferably, the acrylate soft monomer component is butyl acrylate and isooctyl acrylate, and their parts by mass are: 15.0 - 20.0 parts of butyl acrylate, 5.0 - 10.0 parts of isooctyl acrylate.

[0015] More preferably, the acrylate soft monomer component is butyl acrylate and isooctyl acrylate, and their parts by mass are: 20.0 parts of butyl acrylate, 10.0 parts of isooctyl acrylate.

[0016] Preferably, the acrylate hard monomer component is one or more of methyl methacrylate, butyl methacrylate, 2 - phenoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, methyl acrylate, ethyl acrylate.

[0017] More preferably, the acrylate hard monomer component is methyl methacrylate and 2 - phenoxyethyl methacrylate, and their parts by mass are: 2.0 - 5.0 parts of methyl methacrylate, 1.0 - 3.0 parts of 2 - phenoxyethyl methacrylate.

[0018] More preferably, the acrylate hard monomer component is methyl methacrylate and 2 - phenoxyethyl methacrylate, and their parts by mass are: 3.0 parts of methyl methacrylate, 2.0 parts of 2 - phenoxyethyl methacrylate.

[0019] Preferably, the acrylate functional monomer component is one or more of hydroxypropyl acrylate, 2 - hydroxyethyl methacrylate, 2 - hydroxyethyl acrylate, methacrylic acid, acrylic acid, itaconic acid, β - carboxyethyl acrylate, glycidyl methacrylate.

[0020] More preferably, the acrylate functional monomer component is hydroxypropyl acrylate, β-carboxyethyl acrylate and glycidyl methacrylate, and the mass parts of the three are: 2.0-5.0 parts of hydroxypropyl acrylate, 2.0-5.0 parts of β-carboxyethyl acrylate, and 1.0-5.0 parts of glycidyl methacrylate.

[0021] More preferably, the acrylate functional monomer component is hydroxypropyl acrylate, β-carboxyethyl acrylate and glycidyl methacrylate, and the mass parts of the three are: 3.0 parts of hydroxypropyl acrylate, 2.0 parts of β-carboxyethyl acrylate, and 3-4.5 parts of glycidyl methacrylate.

[0022] Preferably, the special crosslinking monomer component is one or more of hydroxymethylurea and its polycondensation products, hydroxymethylphenol compounds, and hydroxymethylmelamine compounds;

[0023] The hydroxymethylurea and its polycondensation products are the products after the reaction of urea and formaldehyde, specifically one or more of monohydroxymethylurea, dihydroxymethylurea, trihydroxymethylurea, urea-formaldehyde resin powder, and melamine resin powder;

[0024] The urea-formaldehyde resin powder is Dongguan Rongda Chemical Industry RD type environmental protection E1 grade urea-formaldehyde resin powder or Guangzhou Jiebu Chemical Industry BD2011 type environmental protection E1 grade urea-formaldehyde resin powder. The melamine resin powder is Guangzhou Yongtene Wood Glue PF61 type environmental protection E1 grade melamine resin powder.

[0025] The hydroxymethylphenol compounds are one or more of monohydroxymethylphenol, dihydroxymethylphenol, and trihydroxymethylphenol.

[0026] The hydroxymethylmelamine compounds are one or more of monohydroxymethylmelamine, dihydroxymethylmelamine, trihydroxymethylmelamine, tetrahydroxymethylmelamine, pentahydroxymethylmelamine, and hexahydroxymethylmelamine.

[0027] The emulsifier is a combination of an anionic emulsifier and a reactive emulsifier. Among them, the anionic emulsifier is one of ammonium nonylphenol polyoxyethylene ether sulfate, sodium alkyl alcohol alkoxylated sulfate, ammonium nonylphenol ethoxylated sulfate, sodium alkyl alcohol ethoxylated sulfate, and sodium dodecyl sulfate; the reactive emulsifier is one of sodium vinyl sulfonate, sodium allyl sulfonate, and 2-acrylamide-2-methylpropanesulfonic acid sodium.

[0028] Preferably, the emulsifier is a combination of ammonium nonylphenol polyoxyethylene ether sulfate (AS801, Dow) and 2-acrylamide-2-methylpropanesulfonic acid sodium;

[0029] The emulsifier is ammonium nonylphenol polyoxyethylene ether sulfate (AS801, Dow) and 2-acrylamide-2-methylpropanesulfonic acid sodium, and the mass ratio of the two is 1:2.

[0030] The initiator is ammonium persulfate.

[0031] A preparation method of a glue for printing and laminating a polyethylene protective film includes the following preparation steps: Add 25% deionized water into a pre-emulsification kettle, then add 85% anionic emulsifier ammonium nonylphenol polyoxyethylene ether sulfate and all of the reactive emulsifier 2-acrylamide-2-methylpropanesulfonic acid sodium salt, stir to mix, then add the initiator ammonium persulfate, and then sequentially add an acrylate soft monomer component, an acrylate hard monomer component, and an acrylate functional monomer component, and emulsify for 1 h to obtain a pre-emulsion; Meanwhile, add the remaining 75% deionized water and the remaining 15% anionic emulsifier ammonium nonylphenol polyoxyethylene ether sulfate into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, the dropping time is 3.0 h, after the dropping is completed, heat up to 90 °C, keep the temperature for reaction for 2.0 h, then cool down to 70 °C, add a special crosslinking monomer component, continue to react for 0.5 h and then end the reaction, when the temperature is cooled down to 50 °C, adjust the pH to 7-8 with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the final product glue.

[0032] The glue for printing and laminating a polyethylene protective film of the present application is mainly applied to the printing and lamination of polyethylene protective films in fields such as aluminum profiles, aluminum-plastic panels, carbon profiles, and plastic profiles.

[0033] Beneficial effects:

[0034] (1) The present invention adopts the traditional polyacrylate emulsion polymerization process. On the basis of regulating and optimizing the types and proportions of acrylate soft, hard, and functional monomers, by introducing special crosslinking monomers with high adhesive force components, polar groups such as hydroxyl groups, ether bonds, primary amine groups, secondary amine groups, and tertiary amine groups are further increased, thereby significantly improving and enhancing the adhesive performance of the polyacrylate adhesives. At the same time, when used as a glue for printing and laminating a polyethylene protective film, it shows excellent adhesive lamination efficiency and tear resistance.

[0035] (2) The glue for printing and laminating a polyethylene protective film designed and obtained by the present invention not only effectively improves its adhesive and adhesive lamination efficiency, but also because special crosslinking monomers such as hydroxymethylurea and its polycondensation products contain multiple reactive hydroxymethyl, primary amine, secondary amine, and tertiary amine groups, etc., which can effectively carry out chemical and non-covalent crosslinking with the optimized acrylate soft, hard, and functional monomers of the present invention, thereby effectively improving the crosslinking density of the glue, and thus also endowing the glue for printing and laminating a polyethylene protective film with excellent water resistance.

[0036] (3) The glue for polyethylene protective film printing and lamination of the present invention uses water as a solvent and does not involve other organic solvents, which is green and environmentally friendly; at the same time, this type of special cross-linking monomer component of hydroxymethylurea and its polycondensation products adopted has low cost and high cost performance, so it has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is the adhesion and lamination performance (180° peel strength) of the glue for polyethylene protective film printing and lamination prepared in the typical embodiment and comparative example of the present invention;

[0038] Figure 2 It is the adhesion and lamination effect (tear resistance) of the glue for polyethylene protective film printing and lamination prepared in the typical embodiment and comparative example of the present invention;

[0039] Figure 3 It is the adhesion and lamination effect (soaked in water for 12 h) of the glue for polyethylene protective film printing and lamination prepared in the typical embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0040] The technical solutions of the present invention will be further described below in conjunction with specific embodiments, but are not limited thereto.

[0041] Example 1

[0042] A preparation method of a glue for polyethylene protective film printing and lamination is as follows: Add 15.0 kg of deionized water to a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid emulsifier, stir and mix evenly, then add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier to a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C, continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of monohydroxymethylurea, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for polyethylene protective film printing and lamination.

[0043] Example 2

[0044] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then successively add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h. Then cool down to 70 °C, add 2.0 kg of dimethylolurea, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the glue for printing and laminating polyethylene protective film.

[0045] Example 3

[0046] A glue for printing and laminating polyethylene protective film and a preparation method, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then successively add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h. Then cool down to 70 °C, add 2.0 kg of trimethylolurea, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the glue for printing and laminating polyethylene protective film.

[0047] Example 4

[0048] A preparation method of glue for printing and compounding of polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then sequentially add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of environmentally friendly E1 grade urea-formaldehyde resin powder (RD type of Dongguan Rongda Chemical Industry), continue to react for 20 min, and then end the reaction. When cooling down to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for printing and compounding of polyethylene protective film.

[0049] Example 5

[0050] A preparation method of glue for printing and compounding of polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then sequentially add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of environmentally friendly E1 grade urea-formaldehyde resin powder (BD2011 type of Guangzhou Jiebu Chemical Industry), continue to react for 20 min, and then end the reaction. When cooling down to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for printing and compounding of polyethylene protective film.

[0051] Example 6

[0052] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence. Emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h. Then cool down to 70 °C, add 2.0 kg of environmentally friendly E1-grade melamine glue powder (PF61 type of Guangzhou Yongtengnai Wood Glue), continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the glue for printing and laminating polyethylene protective film.

[0053] Example 7

[0054] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence. Emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h. Then cool down to 70 °C, add 3.0 kg of dimethylolurea, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the glue for printing and laminating polyethylene protective film.

[0055] Example 8

[0056] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence. Emulsify for 1 h to obtain a pre-emulsion. Meanwhile, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h. Then cool down to 70 °C, add 3.0 kg of trihydroxymethyl urea, continue to react for 20 min, and then end the reaction. When cooling down to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the glue for printing and laminating polyethylene protective film.

[0057] Example 9

[0058] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence. Emulsify for 1 h to obtain a pre-emulsion. Meanwhile, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h. Then cool down to 70 °C, add 3.0 kg of environmentally friendly E1-grade urea-formaldehyde resin powder (RD type of Dongguan Rongda Chemical Industry), continue to react for 20 min, and then end the reaction. When cooling down to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities through a 180-mesh filter screen to obtain the glue for printing and laminating polyethylene protective film.

[0059] Example 10

[0060] A glue for printing and laminating polyethylene protective film and its preparation method are as follows: Add 15.0 kg of deionized water to a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then sequentially add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier to a polymerization kettle, stir and heat up to 80 °C, start dropping the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 3.0 kg of environmentally friendly E1 grade urea-formaldehyde resin powder (Guangzhou Jiebu Chemical BD2011 type), continue to react for 20 min, then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities through a 180-mesh filter to obtain the glue for printing and laminating polyethylene protective film.

[0061] Example 11

[0062] A preparation method of a glue for printing and laminating polyethylene protective film is as follows: Add 15.0 kg of deionized water to a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then sequentially add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier to a polymerization kettle, stir and heat up to 80 °C, start dropping the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 3.0 kg of environmentally friendly E1 grade melamine resin powder (Guangzhou Yongtene Wood Glue PF61 type), continue to react for 20 min, then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities through a 180-mesh filter to obtain the glue for printing and laminating polyethylene protective film.

[0063] Example 12

[0064] A preparation method of glue for polyethylene protective film printing and compounding, specifically: add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 4.5 kg of glycidyl methacrylate in sequence, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 3.0 kg of trimethylol urea, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter and remove impurities with a 180-mesh filter screen to obtain the glue for polyethylene protective film printing and compounding.

[0065] Example 13

[0066] A preparation method of glue for polyethylene protective film printing and compounding, specifically: add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.5 kg of glycidyl methacrylate in sequence, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of environmentally friendly E1-grade urea-formaldehyde resin powder (RD type of Dongguan Rongda Chemical Industry), continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter and remove impurities with a 180-mesh filter screen to obtain the glue for polyethylene protective film printing and compounding.

[0067] Example 14

[0068] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then sequentially add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, 3.5 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 3.0 kg of environmentally friendly E1 grade urea-formaldehyde resin powder (Guangzhou Jiebu Chemical BD2011 type), continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities through a 180-mesh sieve to obtain the glue for printing and laminating polyethylene protective film.

[0069] Example 15

[0070] A preparation method of glue for printing and laminating polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then sequentially add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, 4.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h. After the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 3.0 kg of environmentally friendly E1 grade melamine resin powder (Guangzhou Yongtene Wood Glue PF61 type), continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities through a 180-mesh sieve to obtain the glue for printing and laminating polyethylene protective film.

[0071] Example 16

[0072] A preparation method of glue for printing and compounding of polyethylene protective film, specifically: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of hexadecyl acrylate, 10.0 kg of octadecyl acrylate, 3.0 kg of butyl methacrylate, 2.0 kg of methyl acrylate, 3.0 kg of (meth)acrylic acid hydroxyethyl ester, 2.0 kg of (meth)acrylic acid, and 4.0 kg of itaconic acid in sequence, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 3.0 kg of environmentally friendly E1 grade melamine glue powder (Guangzhou Yongtengnai Wood Glue PF61 type), continue to react for 20 min, then end the reaction. When cooling down to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for printing and compounding of polyethylene protective film.

[0073] Example 17

[0074] A preparation method of glue for printing and compounding of polyethylene protective film, specifically: Add 10.0 kg of deionized water into a pre-emulsification kettle, then add 0.14 kg of AS801 emulsifier and 0.33 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.5 kg of ammonium persulfate initiator, and then add 15.0 kg of butyl acrylate, 5.0 kg of isooctyl acrylate, 5.0 kg of methyl methacrylate, 3.0 kg of 2-phenoxyethyl methacrylate, 2.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 1.0 kg of glycidyl methacrylate in sequence, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 30 kg of deionized water and 0.03 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 5.0 kg of environmentally friendly E1 grade melamine glue powder (Guangzhou Yongtengnai Wood Glue PF61 type), continue to react for 20 min, then end the reaction. When cooling down to 50 °C, adjust the pH to weak alkalinity with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for printing and compounding of polyethylene protective film.

[0075] Comparative Example 1

[0076] Compared with Example 1, this comparative example does not add the special functional monomer - monohydroxymethylurea.

[0077] A glue for printing and laminating polyethylene protective film and its preparation method are as follows: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then successively add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities through a 180-mesh filter to obtain the glue for printing and laminating polyethylene protective film.

[0078] Comparative Example 2

[0079] Compared with Example 1, in this comparative example, an equal amount of ordinary cross-linking monomer (ethanolamine) is used to replace the special functional monomer - hydroxymethylurea.

[0080] A preparation method of a glue for printing and laminating polyethylene protective film is as follows: Add 15.0 kg of deionized water into a pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamido-2-methylpropanesulfonic acid emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then successively add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate, and emulsify for 1 h to obtain a pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier into a polymerization kettle, stir and heat up to 80 °C, start to dropwise add the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of ethanolamine, continue to react for 20 min, then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities through a 180-mesh filter to obtain the glue for printing and laminating polyethylene protective film.

[0081] Comparative Example 3

[0082] Compared with Example 1, in this comparative example, an equal amount of ordinary cross-linking monomer (diethanolamine) is used to replace the special functional monomer - hydroxymethylurea.

[0083] A preparation method of glue for polyethylene protective film printing and compounding, specifically: Add 15.0 kg of deionized water to the pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence. Emulsify for 1 h to obtain the pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier to the polymerization kettle, stir and heat up to 80 °C, start dropping the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of diethanolamine, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for polyethylene protective film printing and compounding.

[0084] Comparative Example 4

[0085] Compared with Example 1, in this comparative example, an equal amount of ordinary cross-linking monomer (triethanolamine) is used to replace the special functional monomer - hydroxymethylurea.

[0086] A preparation method of glue for polyethylene protective film printing and compounding, specifically: Add 15.0 kg of deionized water to the pre-emulsification kettle, then add 0.43 kg of AS801 emulsifier and 1.0 kg of 2-acrylamide-2-methylpropanesulfonic acid sodium emulsifier. After stirring and mixing evenly, add 0.25 kg of ammonium persulfate initiator, and then add 20.0 kg of butyl acrylate, 10.0 kg of isooctyl acrylate, 3.0 kg of methyl methacrylate, 2.0 kg of 2-phenoxyethyl methacrylate, 3.0 kg of hydroxypropyl acrylate, 2.0 kg of β-carboxyethyl acrylate, and 3.0 kg of glycidyl methacrylate in sequence. Emulsify for 1 h to obtain the pre-emulsion. At the same time, add 45 kg of deionized water and 0.07 kg of AS801 emulsifier to the polymerization kettle, stir and heat up to 80 °C, start dropping the pre-emulsion, control the dropping time to be 3.0 h, after the dropping is completed, heat up to 90 °C and continue to react for 2 h, then cool down to 70 °C, add 2.0 kg of triethanolamine, continue to react for 20 min, and then end the reaction. When the temperature drops to 50 °C, adjust the pH to weakly alkaline with ammonia water, and filter to remove impurities with a 180-mesh filter screen to obtain the glue for polyethylene protective film printing and compounding.

[0087] Performance Test

[0088] The performance test of the glue for printing and laminating polyethylene protective film prepared by the present invention includes basic physical and chemical properties and bonding properties. Among them, the basic physical and chemical properties mainly include appearance, viscosity, stability, emulsion particle size and distribution, etc. The specific results are shown in Table 1. The results show that compared with the commercially available glue for printing and laminating polyethylene protective film, the commercially available sample A (acrylic emulsion pressure-sensitive adhesive SW-01) and the commercially available sample B (acrylic emulsion pressure-sensitive adhesive SW-02) are both purchased from Xiangyang Sanwo Aerospace Film Materials Co., Ltd. The preparation process of the glue for printing and laminating polyethylene protective film prepared by the present invention is stable and there is no gel; moreover, its viscosity is moderate, basically between 80-120 mPa.s (No. 2 rotor * 60 revolutions per minute), which is very suitable for use as the glue for protective film coating. At the same time, its storage stability is good and the liquid does not stratify after being placed for six months; in addition, its particle size is relatively uniform, about 170-200 nm, and the particle size distribution is also narrow, and the PDI is between 0.12-0.21.

[0089] Table 1 Physical and chemical properties of the glue for printing and laminating polyethylene protective film prepared by the present invention

[0090]

[0091] At the same time, the present invention also refers to the test methods of the initial adhesion, holding adhesion and 180° peel strength of the pressure-sensitive adhesive to test and characterize the bonding properties of the glue for printing and laminating polyethylene protective film prepared by the present invention, that is, the initial adhesion of the pressure-sensitive adhesive is tested according to GB / T 31125-2014 "Test Method for Initial Adhesion of Adhesive Tape - Ring Method", the holding adhesion of the pressure-sensitive adhesive is determined according to GB / T 4851-1998 "Test Method for Holding Adhesion of Pressure-Sensitive Adhesive Tape", and the 180° peel strength of the pressure-sensitive adhesive is determined according to GB / T 2792-2014 "Test Method for 180° Peel Strength of Pressure-Sensitive Adhesive Tape". It can be seen from Table 2 that the glue for printing and laminating polyethylene protective film prepared by the present invention has excellent initial adhesion, 180° peel strength and holding adhesion, that is, excellent bonding properties, which provides a good premise for the subsequent bonding and laminating efficiency.

[0092] Table 2 Bonding properties of the glue for printing and laminating polyethylene protective film prepared by the present invention

[0093]

[0094]

[0095] In addition, the present invention also improves the 180° peel strength determination method to measure the bonding and laminating performance of the glue for printing and laminating polyethylene protective film, that is, a biaxially stretched black and white polyethylene film with a certain thickness is selected as the base film and the surface film, and a 6-mil coating rod (the coating amount is about 3.0 g / m 2)On the corona surface of a biaxially stretched black and white polyethylene film (5.7 filaments, approximately 0.057 mm, 30 cm * 20 cm), apply evenly the glue for polyethylene protective film printing and compounding. Then, place the polyethylene composite film in an oven at 75 °C for 15 min. After taking it out and cooling, evenly cover the corona surface of another black and white polyethylene film (5.7 filaments, approximately 0.057 mm, 30 cm * 20 cm) with the base film adhesive layer, and evenly compact it with a rubber roller to obtain the polyethylene composite film. Then, measure its 180° peel strength in accordance with GB / T 2792-2014 "Test Method for 180° Peel Strength of Pressure-Sensitive Adhesive Tapes", and use the 180° peel strength and deformation conditions (slight deformation, large deformation, extra-large deformation) as the basis for measuring the quality of the bonding and compounding performance. The results of the bonding and compounding performance of the glue for polyethylene protective film printing and compounding are shown in Table 3 and Figure 1 as shown.

[0096] Table 3 Bonding and compounding performance of the glue for polyethylene protective film printing and compounding prepared in the present invention

[0097]

[0098]

[0099] In addition, in addition to using the traditional three mechanical property indicators (initial adhesion, holding power, and 180° peel strength) to measure the bonding performance of the glue for polyethylene protective film printing and compounding, the present invention also refers to the most direct method commonly used in the industry when printing and compounding polyethylene (PE) plastic films, that is, tearing the prepared polyethylene composite film by hand, and using the degree of deformation and inability to tear apart of the polyethylene composite film as the measurement standard, with the larger the tearing deformation or the more difficult to tear apart of the polyethylene composite film being better. The present invention also uses a simple hand tearing method to evaluate the compounding effect of the polyethylene protective film, and uses the ease of tearing, that is, the tear resistance (easy to tear, difficult to tear, unable to tear) and deformation conditions (slight deformation, large deformation, extra-large deformation) as the evaluation criteria. The preparation of the polyethylene printed composite film is as follows: Use a 6-wire coating rod (coating amount is approximately 3.0 g / m 2 ) to evenly apply the glue for polyethylene protective film printing and compounding on the corona surface of a biaxially stretched black and white polyethylene film (5.7 filaments, approximately 0.057 mm, 30 cm * 20 cm). Then, place the polyethylene composite film in an oven at 75 °C for 15 min. After taking it out and cooling, evenly cover the corona surface of a transparent polyethylene plastic film (2.3 filaments, approximately 0.023 mm) with the base film adhesive layer, and evenly compact it with a rubber roller to obtain the polyethylene composite film. The results of the bonding and compounding performance of the glue for polyethylene protective film printing and compounding are shown in Table 4 and Figure 2 as shown.

[0100] Table 4 Bonding and compounding performance of the glue for polyethylene protective film printing and compounding prepared in the present invention

[0101]

[0102]

[0103] For the protective film, poor water resistance will cause problems such as water absorption and bubbling, cracking, peeling, and whitening during the subsequent use of the protective film, which will affect the use performance of the protective film. Therefore, in this paper, the water absorption rate and water white resistance of the glue for polyethylene protective film printing and compounding were also characterized, and the results are shown in Table 5. Among them, for Comparative Example 1 without adding special crosslinking monomers of hydroxymethylurea and its polycondensation products, the water absorption rate of the glue film is high, and the water absorption rate in 24 hours is 13.41% respectively. For Examples 1-15 with the addition of special crosslinking monomers of hydroxymethylurea and its polycondensation products, the water absorption rate of the glue film in 24 hours decreases significantly, and the water absorption rate in 24 hours is lower than 10%; moreover, the water white resistance of the glue film after soaking in water is excellent, and there is no phenomenon of whitening or bluing of the glue film. It is precisely because the multi-reactive hydroxyl groups contained in the special crosslinking monomers of hydroxymethylurea and its polycondensation products effectively undergo chemical bonding crosslinking with the optimized acrylic (ester) soft, hard, and functional monomers of the present invention, thereby effectively improving the crosslinking density of the system, and thus endowing the glue for polyethylene protective film printing and compounding with excellent water resistance.

[0104] Table 5 Bonding and compounding properties of the glue for polyethylene protective film printing and compounding prepared in the present invention

[0105]

[0106]

[0107] Finally, we also characterized the bonding and compounding efficiency of the polyethylene printed composite film after soaking in water for 12 hours, which was prepared from the glue for polyethylene protective film printing and compounding based on the typical embodiments of the present invention. The results are as Figure 3 shown. The preparation of the polyethylene printed composite film prepared from the glue for polyethylene protective film printing and compounding based on the typical embodiments of the present invention is as follows: Use a 6-mil coating rod (the coating amount is about 3.0 g / m 2 ) to uniformly coat the glue for polyethylene protective film printing and compounding on the corona surface of a biaxially stretched black and white polyethylene film (5.7 mils, about 0.057 mm, 30 cm * 20 cm). Then, place the polyethylene composite film in an oven at 75 °C for 15 minutes. After taking it out and cooling, evenly cover the corona surface of the transparent polyethylene plastic film (2.3 mils, about 0.023 mm) on the base film glue layer, and uniformly press it with a rubber roller to obtain the polyethylene composite film. As can be seen from the figure, the polyethylene printed composite film prepared from the glue for polyethylene protective film printing and compounding based on the typical embodiments of the present invention still has high tear resistance after soaking in water for 12 hours, with a firm composite strength and cannot be torn open.

[0108] In summary, the glue for polyethylene protective film printing and lamination prepared by the present invention not only has excellent bonding performance, but also exhibits remarkable bonding and lamination efficiency, and excellent water resistance. It can be widely used in the printing and lamination of polyethylene protective films for aluminum profiles, aluminum composite panels, carbon profiles, plastic profiles and other fields, so it has broad application prospects. This is achieved by first screening, regulating and optimizing the types and proportions of soft, hard and functional monomers of acrylic (ester) monomers, and then introducing hydroxymethylurea and its polycondensation products with high adhesion components.

[0109] It should be noted that the above-mentioned embodiments are only some of the preferred embodiments for implementing the present invention, rather than all embodiments. Obviously, based on the above embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A glue for printing and laminating polyethylene protective film, characterized in that: The invention comprises the following raw materials in parts by weight: 20.0-30.0 parts of acrylate soft monomer component, 5.0-8.0 parts of acrylate hard monomer component, 5.0-10.0 parts of acrylate functional monomer component, 2.0-5.0 parts of special cross-linking monomer component, 0.5-1.5 parts of emulsifier, 0.25-0.5 parts of initiator and 40.0-60.0 parts of deionized water.

2. The glue for printing and laminating polyethylene protective film according to claim 1, characterized in that: The acrylic ester soft monomer component is one or more of butyl acrylate, isooctyl acrylate, hexadecyl acrylate and octadecyl acrylate.

3. The glue for printing and laminating polyethylene protective film according to claim 2, characterized in that: The acrylic soft monomer component is butyl acrylate and isooctyl acrylate, and the weight proportions of the two are: 15.0-20.0 parts of butyl acrylate and 5.0-10.0 parts of isooctyl acrylate.

4. The glue for printing and laminating polyethylene protective film according to claim 1, characterized in that: The acrylic acid ester hard monomer component is one or more of methyl methacrylate, butyl methacrylate, 2-phenoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, methyl acrylate and ethyl acrylate.

5. The glue for printing and laminating polyethylene protective film according to claim 4, characterized in that: The acrylic ester hard monomer component is methyl methacrylate and 2-phenoxyethyl methacrylate, and the weight proportions of the two are: 2.0-5.0 parts of methyl methacrylate and 1.0-3.0 parts of 2-phenoxyethyl methacrylate.

6. The glue for printing and laminating polyethylene protective film according to claim 1, characterized in that: The acrylic acid ester functional monomer component is hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, methacrylic acid, acrylic acid, itaconic acid, β- - one or more of carboxyethyl acrylate and glycidyl methacrylate.

7. The glue for printing and laminating polyethylene protective film according to claim 6, characterized in that: The acrylate functional monomer components are hydroxypropyl acrylate, β-carboxyethyl acrylate and glycidyl methacrylate, and the weight parts of the three are: 2.0-5.0 parts of hydroxypropyl acrylate, 2.0-5.0 parts of β-carboxyethyl acrylate, and 1.0-5.0 parts of glycidyl methacrylate.

8. The glue for printing and laminating polyethylene protective film according to claim 1, characterized in that: The special cross-linking monomer component is methylol urea and its condensation product; the methylol urea and its condensation product are the products of the reaction between urea and formaldehyde, specifically one or more of monomethylol urea, dimethylol urea, trimethylol urea, urea-formaldehyde resin powder, and melamine powder; the emulsifier is nonylphenol polyoxyethylene ether ammonium sulfate and 2-acrylamide-2-methylpropane sulfonate sodium, and the mass ratio of the two is 1:

2.

9. A method for preparing the glue for printing and laminating the polyethylene protective film according to any one of claims 1 to 8, characterized in that: The method comprises the following preparation steps: adding 25% of deionized water into a pre-emulsification kettle, then adding 85% of anionic emulsifier nonylphenol polyoxyethylene ether sulfate ammonium salt and all reactive emulsifier 2-acrylamide-2-methylpropane sulfonate sodium, stirring and mixing, then adding initiator ammonium persulfate, then sequentially adding acrylate soft monomer component, acrylate hard monomer component and acrylate functional monomer component, emulsifying for 1 hour, and obtaining a pre-emulsified liquid; at the same time, adding the remaining 75% of deionized water and the remaining 15% of anionic emulsifier nonylphenol polyoxyethylene ether ammonium sulfate are stirred and heated to 80°C, and the pre-emulsion is added dropwise for 3.0 hours. After the addition is completed, the temperature is raised to 90°C, and the temperature is kept at 70°C for 2.0 hours. The special cross-linking monomer component is added, and the reaction is continued for 0.5 hours before the reaction is terminated. When the temperature is lowered to 50°C, ammonia water is used to adjust the pH to 7-8, and a 180-mesh filter is used to filter and remove impurities to obtain the final product glue.

10. An application of the glue for printing and laminating polyethylene protective film according to any one of claims 1 to 8, characterized in that: It is used in the printing and lamination of protective films of aluminum profiles, aluminum-plastic panels, carbon profiles and plastic profiles.

Images