Polyacrylate pressure-sensitive adhesive for lap joint of engineering geotextile and preparation method of polyacrylate pressure-sensitive adhesive

Abstract

The invention relates to the field of high polymer materials, and provides a polyacrylate pressure-sensitive adhesive for lap joint of engineering geotextile and a preparation method of the polyacrylate pressure-sensitive adhesive. Wherein the dosage of each component is respectively 20-60 parts by weight of soft monomer, 2-30 parts by weight of hard monomer, 1-10 parts by weight of functional monomer, 0.1-5 parts by weight of initiator, 0.1-5 parts by weight of cross-linking agent or coupling agent, 1-30 parts by weight of tackifying aid, 1-30 parts by weight of rheology regulating additive and 20-65 parts by weight of solvent; the adhesive is prepared from acrylic acid raw materials in a specific proportion, has good brush coating and roller coating constructability, excellent base material wettability and enough strong stripping force and permanent adhesion, and does not have a disengagement phenomenon when being used for bonding geotechnical cloth for lap joint.

Description

Technical Field

[0001] The invention relates to the field of polymer materials, and in particular to a polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles and a preparation method thereof. Background Art

[0002] Geotextile, also known as geotextile, is a water-permeable geosynthetic material made of synthetic fibers through needle punching or weaving. Geotextile is one of the new geosynthetics. The finished product is in the shape of cloth, generally 4-6 meters wide and 50-100 meters long. It is widely used in railway roadbed reinforcement, highway pavement maintenance, sports halls, dam protection, hydraulic construction isolation, tunnels, coastal beaches, reclamation, environmental protection and other projects.

[0003] In the prior art, the geotextile is overlapped and fixed by sewing with needles and threads. However, in some places, the terrain is irregular, and it is difficult for people to go in and pull up the cloth for construction. In some places, the slope is too large, so the needles and threads cannot bear the load and break, and multiple sewing is required. In addition, the use of high-strength or thick threads will increase costs and increase the physical exertion of workers. In the prior art, tools are mostly used to fix overlapping geotextiles, such as CN103215940A, a overlapping device for geotextile on the upper layer of a composite geomembrane, CN104652403A, a method for overlapping and laying underwater geotextiles, and CN206815306U, a butt-jointed geotextile. The working efficiency is low and the cost is high. In addition, for the special materials of geotextiles, the glue in the prior art is generally water-based, and the water evaporates slowly and is easily absorbed by the geotextile, so a good overlapping effect is generally not achieved, and there is a lack of a glue specifically for geotextiles. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a polyacrylate pressure-sensitive adhesive for geotextile engineering which is quick-drying, low in VOC, and convenient to apply with a brush or a roller.

[0005] The pressure-sensitive adhesive, wherein the amounts of the components in parts by weight are 20-60 parts of soft monomer, 2-30 parts of hard monomer, 1-10 parts of functional monomer, 0.1-5 parts of initiator, 0.1-5 parts of crosslinking agent or coupling agent, 1-30 parts of tackifier, 1-30 parts of rheology adjusting additive, and 20-65 parts of solvent; The glass transition temperature of the pressure-sensitive adhesive is preferably between -60°C and -20°C; The soft monomer is a mixture of one or more of ethyl acrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, lauryl acrylate, lauryl methacrylate, octadecyl acrylate, and octadecyl methacrylate.

[0006] The hard monomer is a mixture of one or more of methyl acrylate, methyl methacrylate, styrene, isobornyl methacrylate, isobornyl acrylate, cyclohexyl acrylate, cyclohexyl methacrylate, and vinyl acetate.

[0007] The functional monomer is a mixture of one or more of acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, N-hydroxymethylpropionamide, acrylamide, glycidyl methacrylate, and dimethylaminoethyl methacrylate.

[0008] The initiator is a mixture of one or more of azobisisobutyronitrile, 1,4-di(tert-butylperoxy)cyclohexane, azobisisoheptanenitrile, azobisisovaleronitrile, benzoyl peroxide, diisopropylbenzene peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide, tert-butyl peroxide 2-ethylhexyl ester, and 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane.

[0009] The crosslinking agent is a mixture of one or more of aluminum triacetylacetonate, tetraisobutyl titanate, diisobutyl diacetonate titanate, isocyanate curing agent, and epoxy curing agent.

[0010] The tackifier is a mixture of one or more of rosin resin, terpene resin, terpene phenolic resin, petroleum resin and epoxy resin.

[0011] The rheology adjusting additive is a mixture of one or more of nitrocellulose, cellulose acetate butyrate, gelatin, calcium carbonate, titanium dioxide and carbon black.

[0012] The solvent is a mixture of one or more of ethyl acetate, methyl acetate, isopropanol, methanol, ethanol, acetone and dimethyl carbonate.

[0013] The preparation method of the polyacrylate pressure-sensitive adhesive for geotextile engineering is as follows: (1) Prepare the corresponding amounts of each component according to the formula; (2) Add all the prepared solvents, all the monomers and 25% of the initiator into a four-necked flask, heat it to 45°C-70°C, and keep it warm for 3 hours under nitrogen protection; (3) preparing an additional solvent, the amount of which is 20% of the solvent in the previous step, for the operation of eliminating residual monomers; (4) 35% of the initiator and half of the solvent in step (3) were added to a four-necked flask, and then kept at 45°C-70°C for 3 hours under nitrogen protection; (5) All the remaining initiators and half of the remaining solvent in step (3) were added dropwise into a four-necked flask, and then kept at 45°C-70°C for 15 hours under nitrogen protection; (6) Distill under reduced pressure to remove the same amount of solvent as in step (3); this solvent is prepared in addition to the amount in the formula to eliminate residual monomers. The 20% solvent distilled out can be used for other experiments, so the actual amount of solvent used is still the weight in the formula and has not changed; (7) Cool down to below 45°C under nitrogen protection, add all the remaining materials, stir evenly, and filter the material with an 80-mesh filter.

[0014] Compared with the prior art, the first aspect of the present invention provides a quick-drying, low-VOC, and conveniently applied by brush or roller for geotextile engineering polyacrylate pressure-sensitive adhesive, wherein the polyacrylate pressure-sensitive adhesive is prepared by a specific proportion of acrylic raw materials, wherein acrylic monomers are the main film-forming substances, cross-linking agents are used to improve the strength of the adhesive film, and tackifiers are used to increase the wetting and bonding strength of the adhesive to the geotextile, and rheological additives are used to make multiple phases coexist in the system, so that the system has the characteristics of shear thinning, which is convenient for workers to construct, and has good brush and roller construction properties, excellent substrate wettability, high moisture permeability, sufficiently strong peeling force and holding force, and will not come off when used to bond geotextile overlaps; The second aspect of the present invention provides a method for preparing a pressure-sensitive adhesive. The preparation method uses a solvent whose solution itself is mostly less than 4 carbon atoms, which is an environmentally friendly solvent, will not be included in the total carbon emissions, and has a low VOCS; a relatively low temperature polymerization process is used, which can stably control the reaction process and ensure the quality of the product; a process of adding an additional 20% of solvent and then distilling it out under reduced pressure in the later stage is used, and the distilled 20% of solvent can take away a large amount of residual monomers. When the reaction conversion degree of the monomer reaches the limit, the residual monomer is further greatly reduced, ensuring that the odor of the adhesive construction in the later stage is low. DETAILED DESCRIPTION

[0015] In order to better illustrate the present invention and facilitate understanding of the technical solution of the present invention, the present invention is further described in detail with specific implementation methods below. However, the following embodiments are only simple examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0016] Embodiment 1: (1) Prepare the corresponding amounts of the components according to the formula: 1.5 parts of methacrylic acid, 0.5 parts of hydroxyethyl acrylate, 20 parts of butyl acrylate, 10 parts of 2-ethylhexyl acrylate, 5 parts of vinyl acetate, 0.5 parts of 1,4-di(tert-butylperoxy)cyclohexane, 3 parts of rosin tackifying resin, 54 parts of methyl acetate, 5 parts of nitrocellulose, and 0.5 parts of epoxidized m-xylenediamine as an external crosslinking agent.

[0017] (2) Add all the prepared solvents, all the monomers and 25% of the initiator into a four-necked flask, heat it to 45°C-70°C, and keep it warm for 3 hours under nitrogen protection; (3) preparing an additional solvent, the amount of which is 20% of the solvent in the previous step, for the operation of eliminating residual monomers; (4) 35% of the initiator and half of the solvent in step (3) were added to a four-necked flask, and then kept at 45°C-70°C for 3 hours under nitrogen protection; (5) All the remaining initiators and half of the remaining solvent in step (3) were added dropwise into a four-necked flask, and then kept at 45°C-70°C for 15 hours under nitrogen protection; (6) distilling off the same amount of solvent as in step (3) under reduced pressure; (7) Cool down to below 45°C under nitrogen protection, add all the remaining materials, stir evenly, and filter the material with an 80-mesh filter.

[0018] (8) Before use, mix the glue and curing agent epoxidized meta-phenylenediamine in a ratio of 99.5:0.5 and stir evenly before coating.

[0019] Embodiment 2: (1) Prepare the following components in the following amounts: 0.5 parts of acrylic acid, 2 parts of hydroxyethyl methacrylate, 10 parts of butyl acrylate, 30 parts of 2-ethylhexyl acrylate, 2 parts of tert-butyl methacrylate, 0.2 parts of 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 0.5 parts of 1,4-di(tert-butylperoxy)cyclohexane, 5 parts of epoxy resin, 45.8 parts of dimethyl carbonate, 2 parts of cellulose acetate butyrate, and 2 parts of crosslinking agent aluminum triacetylacetonate.

[0020] (2) Add all the prepared solvents, all the monomers and 25% of the initiator into a four-necked flask, heat it to 45°C-70°C, and keep it warm for 3 hours under nitrogen protection; (3) preparing an additional solvent, the amount of which is 20% of the solvent in the previous step, for the operation of eliminating residual monomers; (4) 35% of the initiator and half of the solvent in step (3) were added to a four-necked flask, and then kept at 45°C-70°C for 3 hours under nitrogen protection; (5) All the remaining initiators and half of the remaining solvent in step (3) were added dropwise into a four-necked flask, and then kept at 45°C-70°C for 15 hours under nitrogen protection; (6) distilling off the same amount of solvent as in step (3) under reduced pressure; (7) Cool down to below 45°C under nitrogen protection, add all the remaining materials, stir evenly, and filter the material with an 80-mesh filter.

[0021] Embodiment 3: (1) Prepare the corresponding amounts of the components according to the formula: 8 parts of acrylic acid, 40 parts of lauryl acrylate, 3 parts of isobornyl methacrylate, 1 part of tert-butyl hydroperoxide, 4 parts of terpene phenol resin, 36 parts of ethanol, 3 parts of gelatin, 1 part of calcium carbonate, and 0.5 parts of cross-linking agent tetraisobutyl titanate.

[0022] (2) Add all the prepared solvents, all the monomers and 25% of the initiator into a four-necked flask, heat it to 45°C-70°C, and keep it warm for 3 hours under nitrogen protection; (3) preparing an additional solvent, the amount of which is 20% of the solvent in the previous step, for the operation of eliminating residual monomers; (4) 35% of the initiator and half of the solvent in step (3) were added to a four-necked flask, and then kept at 45°C-70°C for 3 hours under nitrogen protection; (5) All the remaining initiators and half of the remaining solvent in step (3) were added dropwise into a four-necked flask, and then kept at 45°C-70°C for 15 hours under nitrogen protection; (6) distilling off the same amount of solvent as in step (3) under reduced pressure; (7) Cool down to below 45°C under nitrogen protection, add all the remaining materials, stir evenly, and filter the material with an 80-mesh filter.

[0023] Comparative case 1: (1) Prepare the corresponding amounts of the components according to the formula: 1.5 parts of methacrylic acid, 0.5 parts of hydroxyethyl acrylate, 20 parts of butyl acrylate, 10 parts of 2-ethylhexyl acrylate, 5 parts of vinyl acetate, 0.5 parts of 1,4-di(tert-butylperoxy)cyclohexane, 3 parts of rosin tackifying resin, 59 parts of methyl acetate, and 0.5 parts of epoxidized meta-xylylenediamine as an external crosslinking agent.

[0024] (2) Add 100% of the solvent, 100% of the monomer and 25% of the initiator in Comparative Example 1 into a four-necked flask, heat it to 55°C, and keep it warm for 3 hours under nitrogen protection; (3) Prepare an additional 20% of solvent outside the formula to eliminate residual monomers.

[0025] (4) 35% of the initiator and the additional amount of solvent were added to a four-necked flask, and then kept at 55°C for 3 hours under nitrogen protection; (5) The remaining 40% initiator and an additional 10% solvent were added to the four-necked flask, and then the mixture was kept at 55°C for 15 hours under nitrogen protection.

[0026] (6) Distill out 20% of the solvent under reduced pressure and store it in a special container, which can be used for other experiments.

[0027] (7) Cool down to below 45°C under nitrogen protection, add all the remaining materials except the curing agent, stir evenly, and filter the material with an 80-mesh filter.

[0028] (8) Before use, mix the glue and curing agent epoxidized meta-phenylenediamine in a ratio of 99.5:0.5 and stir evenly before coating.

[0029] Comparative Case 2: (1) Prepare the corresponding amounts of the components according to the formula: 1.5 parts of methacrylic acid, 0.5 parts of hydroxyethyl acrylate, 20 parts of butyl acrylate, 10 parts of 2-ethylhexyl acrylate, 5 parts of vinyl acetate, 0.5 parts of 1,4-di(tert-butylperoxy)cyclohexane, 3 parts of rosin tackifying resin, 54 parts of methyl acetate, 5 parts of nitrocellulose, and 0.5 parts of epoxidized m-xylenediamine as an external crosslinking agent.

[0030] (2) Add 100% of the solvent, 100% of the monomer and 25% of the initiator in Comparative Example 2 into a four-necked flask, raise the temperature to 55°C, and keep it warm for 3 hours under nitrogen protection.

[0031] (3) Add 35% initiator into a four-necked flask and keep it at 55°C for 3 hours under nitrogen protection; (4) The remaining 40% of the initiator was added into the four-necked flask and then kept at 55°C for 15 hours under nitrogen protection.

[0032] (5) Cool down to below 45°C under nitrogen protection, add all the remaining materials except the curing agent, stir evenly, and filter the material with an 80-mesh filter.

[0033] (6) Before use, mix the glue and curing agent epoxidized meta-phenylenediamine in a ratio of 99.5:0.5 and stir evenly before coating.

[0034] Test data comparison:

[0035] The painting and actual application effects of Example 1, Example 2 and Example 3 are all satisfactory; Comparative Example 1 does not add rheological additives, resulting in the inability to maintain the glue surface and a large amount of glue penetrating into the geotextile; the same situation occurs with the common glue 1 and the common glue 2 on the market; Comparative Example 2 does not perform the residual monomer removal process, resulting in obvious odor, which cannot meet the low odor requirement during construction.

[0036] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles, characterized in that: The amounts of the components in parts by weight are 20-60 parts of soft monomer, 2-30 parts of hard monomer, 1-10 parts of functional monomer, 0.1-5 parts of initiator, 0.1-5 parts of crosslinking agent or coupling agent, 1-30 parts of viscosity enhancing agent, 1-30 parts of rheology adjusting additive and 20-65 parts of solvent.

2. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The soft monomer is a mixture of one or more of ethyl acrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, lauryl acrylate, lauryl methacrylate, octadecyl acrylate, and octadecyl methacrylate.

3. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The hard monomer is a mixture of one or more of methyl acrylate, methyl methacrylate, styrene, isobornyl methacrylate, isobornyl acrylate, cyclohexyl acrylate, cyclohexyl methacrylate, and vinyl acetate.

4. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The functional monomer is a mixture of one or more of acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, N-hydroxymethylpropionamide, acrylamide, glycidyl methacrylate, and dimethylaminoethyl methacrylate.

5. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The initiator is a mixture of one or more of azobisisobutyronitrile, 1,4-di(tert-butylperoxy)cyclohexane, azobisisoheptylnitrile, azobisisovaleronitrile, benzoyl peroxide, diisopropylbenzene peroxide, di-tert-butyl peroxide, tert-butyl hydroperoxide, tert-butyl peroxide 2-ethylhexyl ester, and 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane.

6. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The crosslinking agent is a mixture of one or more of aluminum triacetylacetonate, tetraisobutyl titanate, diisobutyl diacetonate titanate, isocyanate curing agent, and epoxy curing agent.

7. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The tackifying aid is a mixture of one or more of rosin resin, terpene resin, terpene phenolic resin, petroleum resin and epoxy resin.

8. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The rheology adjusting additive is a mixture of one or more of nitrocellulose, cellulose acetate butyrate, gelatin, calcium carbonate, titanium dioxide and carbon black.

9. The polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles according to claim 1, characterized in that: The solvent is a mixture of one or more of ethyl acetate, methyl acetate, isopropanol, methanol, ethanol, acetone and dimethyl carbonate.

10. A method for preparing the polyacrylate pressure-sensitive adhesive for overlapping engineering geotextiles as claimed in any one of claims 1 to 9, characterized in that: Here are the steps: (1) Prepare the corresponding amounts of each component according to the formula; (2) Add all the prepared solvents, all the monomers and 25% of the initiator into a four-necked flask, heat it to 45°C-70°C, and keep it warm for 3 hours under nitrogen protection; (3) preparing an additional solvent, the amount of which is 20% of the solvent in the previous step, for the operation of eliminating residual monomers; (4) 35% of the initiator and half of the solvent in step (3) were added to a four-necked flask, and then kept at 45°C-70°C for 3 hours under nitrogen protection; (5) All the remaining initiators and half of the remaining solvent in step (3) were added dropwise into a four-necked flask, and then kept at 45°C-70°C for 15 hours under nitrogen protection; (6) distilling off the same amount of solvent as in step (3) under reduced pressure; (7) Cool down to below 45°C under nitrogen protection, add all the remaining materials, stir evenly, and filter the material with an 80-mesh filter.

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