A waterproof adhesive for wet-laid waterproof roll material and preparation method thereof

Abstract

The invention relates to the field of waterproof materials, and specifically to a waterproof adhesive for wet-laid waterproof coiled materials and a preparation method thereof. In order to solve the problem that the polymer component existing in the polymer cement adhesive blocks the capillary structure, the bubbles mixed in the mortar with the surfactant cannot be discharged in time, forming adhesion defects and poor anti-peeling strength, a new adhesive layer is composed of silicate cement, quartz sand, water, surfactant, long-chain polyacid, cellulose ester, cellulose ether, vinyl acetate, and water-absorbing resin-coated particles to achieve multiple isolation of moisture; the application can reduce the pressure of capillary action during the curing of the cement mortar adhesive, avoid the generation of cracks, will not hinder the discharge of bubbles, and can form a secondary waterproof layer after the cracks are damaged, with secondary adhesion strength and high anti-peeling strength.

Description

Technical Field

[0001] The invention relates to the technical field of waterproof materials, and in particular to a waterproof adhesive for wet-laid waterproof coiled materials and a preparation method thereof. Background Art

[0002] During the construction process of wet-laid waterproof membrane, it is not affected by the base and the construction environment, and can be pasted on damp concrete base and cement mortar base. The reason is that the adhesive used is cement mortar adhesive, which contains 40%-60% water, thus obtaining greater fluidity, and can fully extend and wet the entire space between the wet-laid membrane and the cement base. The cement mortar adhesive is fixed after hydration, and the alkali produced by hydration can produce a certain cross-linking with the active ingredients in the wet-laid membrane, thereby entering the gaps on the surface of the cement mortar to form a mortise and tenon structure with a certain anti-peel strength, thereby realizing the laying of the wet-laid membrane and providing waterproof protection for the cement base.

[0003] There are three types of cement mortar adhesives. One is cement mortar formed by mixing cement and quartz sand with water. The second is cement paste formed by mixing cement with water. The last is polymer cement mortar formed by mixing polymer into cement mortar. However, in the process of using cement adhesives, it is found that cement mortar without polymer added and cement paste will crack and shrink due to external factors such as vibration after long-term use, causing certain cracks on the surface of the roll material. After water enters, it is easy to corrode the cement base layer and the waterproof ability becomes poor. Cement mortar with polymer added contains long organic molecular chains and has certain elasticity. The polymer has good deformation ability and tear resistance, but the organic matter in the polymer molecules and the inorganic matter in the cement mortar need to be stirred with the addition of surfactants. Due to the presence of surfactants, too many bubbles will be mixed in the stirring process, and the untimely discharge will cause the low peeling strength between the polymer mortar adhesive and the wet-laid membrane; the deeper reason is that capillaries will be formed during the cement curing process, causing water to be discharged outward. The presence of polymers slows down the speed of water discharge, and cement mortar is an alkaline environment. Once the polymer adhesive contains unsaturated acid ester monomers, it will be hydrolyzed in an alkaline environment to release RCH 2 COO - , in solution with Ca 2+ The reaction produces organic calcium salts, which reduces the Ca / Si ratio in C-SH and reduces the Ca(OH) in the system. 2 The content of , and reduce the strength of the material, and under the influence of tiny bubbles, weaken the anti-peeling performance of the wet-laid coiled material. Summary of the invention

[0004] In order to solve the problem that the polymer components in the polymer cement adhesive block the capillary structure during the hardening process of concrete, so that the bubbles added to the mortar with added surfactant cannot be discharged in time during the stirring process, resulting in adhesion defects and poor anti-peel strength, the present invention provides a waterproof adhesive for wet-laid waterproof roll materials, which is as follows:

[0005] The invention is prepared from the following raw materials in parts by weight: 24-30 parts of silicate cement, 48-55 parts of quartz sand, 15-20 parts of water, 1.2-1.5 parts of long-chain polyacid, 1.2-1.5 parts of cellulose ester, 1.2-1.5 parts of cellulose ether, 1.2-1.5 parts of vinyl acetate, and 12-15 parts of water-absorbing resin-coated particles;

[0006] The preparation method of the water-absorbing resin coated particles comprises the following steps:

[0007] S1, adding polyvinyl alcohol, glycerol and a stabilizer into hot water and stirring until dissolved to obtain a coating liquid, adding maltose into the coating liquid, stirring and preparing a slurry;

[0008] S2, mixing the water-absorbing resin particles and the inorganic filler in a weight ratio of 1:1.5-3 to form mixed particles, and spraying the slurry evenly on the surface of the mixed particles;

[0009] S3, vacuum drying the mixed particles containing the slurry on the surface to obtain single-layer coated particles;

[0010] Steps S2 and S3 are repeated to obtain water-absorbing resin coated particles, wherein the mass increase ratio of the water-absorbing resin coated particles is 10%-30%.

[0011] Furthermore, the weight ratio of the polyvinyl alcohol, glycerol, maltose and stabilizer is 5:0.75-1.5:1-3:0.05-2.

[0012] The present application adds cellulose ester and cellulose ether to the cement mortar adhesive, which can improve the water retention for a long time, relieve the capillary pressure when the cement produces capillary action, slow down the tensile stress of the capillary pore wall, prevent the shrinkage of the cement slurry, avoid the generation of cracks, and the non-contraction of the capillary can also ensure that the tiny bubbles in the polymer are easy to discharge; in addition, the present application also uses water-absorbing resin coated particles in the cement mortar adhesive, and the outer surface of the coated particles is coated with polyvinyl alcohol, which can prevent the water absorption of the water-absorbing resin in the early stage of cement hydration, retain the water absorption function of the water-absorbing resin, and after the cement adhesive is cured, a protective layer is formed to prevent water from penetrating. The protective mechanism of the protective layer is that When the roll material is cracked or damaged by external factors, moisture penetrates into the cement mortar adhesive layer. At this time, polyvinyl alcohol is affected by the active ingredients in the roll material, such as plasticizers precipitated from the roll material and acted on the surface of polyvinyl alcohol, which weakens the hydrogen bonding effect of polyvinyl alcohol and increases the fluidity and water permeability of polyvinyl alcohol. Therefore, the infiltrated moisture will be absorbed by the water-absorbing resin. After the water-absorbing resin absorbs moisture, its volume increases and blocks cracks and damage. In this application, polyvinyl alcohol is modified with maltose. Under the influence of water molecules, the maltose group has a certain viscosity, thereby strengthening the connection between cement capillaries, damaged gaps and resin, increasing the adhesion effect, thereby preventing excessive water molecules from passing through, and forming a better waterproof effect.

[0013] Furthermore, the finished particle size of the water-absorbing resin coated particles is between 75 microns and 200 microns.

[0014] Further, the preparation steps of the water-absorbing resin are as follows:

[0015] A1. Mix starch and water at a solid-liquid ratio of 1 g:20 mL, and heat in an oxygen-free environment to perform gelatinization reaction;

[0016] A2, mixing the cerium nitrate solution with acrylonitrile to obtain a cerium nitrate solution of acrylonitrile, and adding the cerium nitrate solution containing acrylonitrile to the gelatinized starch solution for grafting reaction;

[0017] A3, using dilute sodium hydroxide to adjust the pH value to neutral and heating to remove unreacted acrylonitrile, adding 2 mol / L sodium hydroxide solution to carry out saponification reaction;

[0018] A4. Use acetic acid to adjust the pH value to neutral, add ethanol for precipitation, filter and crush to obtain a water-absorbing resin.

[0019] The water-absorbent resin used in the present application uses starch and acrylonitrile as raw materials for grafting reaction, grafting acrylonitrile onto gelatinized starch chains. This step uses cerium nitrate as an initiator to initiate the grafting reaction, and then uses sodium hydroxide to transform the nitrile group of acrylonitrile to obtain amide groups and carboxyl groups. It has strong hydrophilicity and can absorb a large amount of water molecules.

[0020] Furthermore, in the gelatinization reaction, the mass ratio of starch to acrylonitrile is 1:1, the gelatinization reaction temperature is 90° C., and the reaction time is 30-60 min.

[0021] Furthermore, the mass ratio of the cerium nitrate to the acrylonitrile is 3-8:100, the concentration of the cerium nitrate solution is 0.1 g / mL, and the solvent for preparing the cerium nitrate solution is 1 mol / L nitric acid.

[0022] Furthermore, the stabilizer in S1 is one of dibutyltin dilaurate or dibutyltin dimaleate, and the inorganic filler in S2 is one of montmorillonite or attapulgite.

[0023] When the slurry is sprayed on the surface of the mixed particles, since the slurry contains a large amount of water, it is easy to absorb water during the coating process and thus increase its volume. In order to slow down the water absorption rate of the highly absorbent resin particles, the present application uses a physical barrier method by adding inorganic fillers with a layered structure to the resin particles to form a physical barrier, increase the path and time of water diffusion, thereby slowing down the water absorption rate, and drying as quickly as possible to form a protective film layer that can initially isolate water.

[0024] Furthermore, the long-chain polyacid is one of dodecanedioic acid and hexadecanedioic acid, and the surfactant is one of EASYTECH ST-5200 and IGEPAL CO-897.

[0025] In the present application, the long-chain polyacid is used to enhance the strength and tear resistance of the adhesive layer, and the molecular layers are interconnected by long chains, thereby increasing the interaction between polymer molecules, improving the overall strength of the adhesive layer, and preventing moisture from entering.

[0026] The present application also provides a method for preparing a waterproof adhesive for wet-laid waterproof coiled material, comprising the following steps:

[0027] The first step is to mix silicate cement, quartz sand and long-chain polyacid, and then add water to prepare a slurry 1.

[0028] In the second step, the water-absorbing resin coated particles are mixed with cellulose ester and cellulose ether, and then added into slurry 1 and stirred evenly to obtain slurry 2; vinyl acetate and surfactant are placed in the remaining water, and slowly added into slurry 2 and stirred to obtain waterproof adhesive for wet-laid waterproof membrane.

[0029] Furthermore, the volume ratio of the water used in the first step to the water used in the second step is 2-3:1.

[0030] The present invention also has the following beneficial effects:

[0031] The polyvinyl alcohol used in the present application has been modified with maltose. Maltose and polyvinyl alcohol have good compatibility, and the combination is simpler and more convenient. The water resistance and stability of the PVA film are improved, and it will not be affected by the water environment during hydration. It has a strong protective ability on the outside of the water-absorbent resin. The maltose on the polyvinyl alcohol will produce partial viscosity after contact with water, thereby enhancing the viscosity of the adhesive. Therefore, when the coil is damaged and water enters for the second time, it will produce a sticky effect when it encounters water; the maltose-modified polyvinyl alcohol is located on the outside of the water-absorbent resin, and the water-absorbent resin can continuously provide water molecules for maltose for a long time, so that its hydrogen bonds continue to work, and it has a longer-term viscosity. Therefore, it has a certain adhesion effect on the coil on the upper layer of the adhesive, and increases the peeling strength and waterproof ability of the coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a line graph of the peeling strength of various embodiments of the present invention and comparative examples. DETAILED DESCRIPTION

[0033] The following will refer to the attached Figure 1 The embodiments of the present invention are described in detail. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0034] Preparation of water-absorbent resin:

[0035] Preparation of water-absorbent resin Example 1

[0036] The preparation steps of water-absorbing resin are as follows:

[0037] A1. Mix 100 g starch with 2000 mL water, stir, and heat to 90°C in a nitrogen environment for gelatinization reaction for 45 min.

[0038] A2, using 1 mol / L nitric acid to prepare a 0.1 g / mL cerium nitrate solution, 50 mL of the cerium nitrate solution was mixed with 100 g of acrylonitrile to obtain an acrylonitrile-cerium nitrate mixture, and the acrylonitrile-containing cerium nitrate mixture was added to the gelatinized starch solution for grafting reaction;

[0039] A3, using dilute sodium hydroxide to adjust the pH value of the above mixture to neutral and heating to 80°C to remove unreacted acrylonitrile, adding 1500 mL of 2 mol / L sodium hydroxide solution to carry out saponification reaction, and the reaction time is 1 hour;

[0040] A4. Use acetic acid to adjust the pH value to neutral, add ethanol to precipitate, stop adding ethanol until the precipitate no longer increases, filter and crush to obtain a water-absorbing resin.

[0041] Preparation of water-absorbent resin Example 2

[0042] The preparation steps of water-absorbing resin are as follows:

[0043] A1. Mix 100 g starch with 2000 mL water, stir, and heat to 90°C in a nitrogen environment for gelatinization reaction for 60 min.

[0044] A2, using 1 mol / L nitric acid to prepare a 0.1 g / mL cerium nitrate solution, mixing 80 mL of the cerium nitrate solution with 100 g of acrylonitrile to obtain an acrylonitrile-cerium nitrate mixture, and adding the acrylonitrile-containing cerium nitrate mixture to the gelatinized starch solution for grafting reaction;

[0045] A3, using dilute sodium hydroxide to adjust the pH value of the above mixture to neutral and heating to 80° C. to remove unreacted acrylonitrile, adding 1700 mL of 2 mol / L sodium hydroxide solution to carry out saponification reaction, and the reaction time is 1 h;

[0046] A4. Use acetic acid to adjust the pH value to neutral, add ethanol to precipitate, stop adding ethanol until the precipitate no longer increases, filter and crush to obtain a water-absorbing resin.

[0047] Preparation Example 1

[0048] Preparation of water-absorbent resin coated particles

[0049] S1. Add 10 g of polyvinyl alcohol, 2 g of glycerol, and 1 g of dibutyltin dilaurate or dibutyltin dimaleate to 300 mL of hot water and stir until dissolved. The hot water temperature is 90° C. to obtain a coating solution. Add 4 g of maltose to the coating solution and stir to obtain a slurry.

[0050] S2, mixing 100 g of the water-absorbent resin particles prepared in Example 1 with 200 g of attapulgite to form mixed particles, and spraying the slurry evenly on the surface of the mixed particles;

[0051] S3, quickly placing the mixed particles with the slurry on the surface into a vacuum drying oven for vacuum drying at a temperature of 260° C. to obtain single-layer coated particles;

[0052] Repeat steps S2 and S3 until the weight of the mixed particles increases to 360 g to obtain water-absorbing resin coated particles, the particle size of the water-absorbing resin coated particles is 120 microns to 150 microns.

[0053] Preparation Example 2

[0054] Preparation of water-absorbent resin coated particles

[0055] S1. Add 10 g of polyvinyl alcohol, 1.5 g of glycerol, and 0.2 g of dibutyltin dimaleate to 300 mL of hot water and stir until dissolved. The hot water temperature is 90° C. to obtain a coating solution. Add 2 g of maltose to the coating solution and stir to obtain a slurry.

[0056] S2, mixing 100 g of the water-absorbent resin particles prepared in Example 1 with 150 g of montmorillonite or attapulgite to form mixed particles, and spraying the slurry evenly on the surface of the mixed particles;

[0057] S3, quickly placing the mixed particles with the slurry on the surface in a vacuum drying furnace for vacuum drying at a temperature of 200° C. to obtain single-layer coated particles;

[0058] Repeat steps S2 and S3 until the weight of the mixed particles increases to 280 g to obtain water-absorbing resin coated particles, the particle size of which is 75 microns to 100 microns.

[0059] Preparation Example 3

[0060] Preparation of water-absorbent resin coated particles

[0061] S1. Add 10 g of polyvinyl alcohol, 3 g of glycerol, and 4 g of dibutyltin dimaleate to 300 mL of hot water and stir until dissolved. The hot water temperature is 90° C. to obtain a coating solution. Add 6 g of maltose to the coating solution and stir to obtain a slurry.

[0062] S2, 100g of the water-absorbent resin particles prepared in Example 2 of the water-absorbent resin preparation method are mixed with 300g of montmorillonite or attapulgite to form mixed particles, and the slurry is evenly sprayed on the surface of the mixed particles;

[0063] S3, quickly placing the mixed particles with the slurry on the surface in a vacuum drying furnace for vacuum drying at a temperature of 300° C. to obtain single-layer coated particles;

[0064] Repeat steps S2 and S3 until the weight of the mixed particles increases to 500 g to obtain water-absorbing resin coated particles, the particle size of which is 150 μm to 200 μm.

[0065] Preparation Example 4: Water-absorbing resin particles are coated with a hydrophobic coating instead of polyvinyl alcohol

[0066] Preparation of water-absorbent resin coated particles

[0067] S1. Add 6 g of perfluoropolyether and 1 g of hydrofluoroether solvent into 200 mL of hot water and stir until dissolved. The hot water temperature is 50° C. to obtain a coating solution. Add 4 g of maltose into the coating solution and stir to obtain a slurry.

[0068] S2, mixing 100 g of the water-absorbent resin particles prepared in Example 1 with 200 g of attapulgite to form mixed particles, and spraying the slurry evenly on the surface of the mixed particles;

[0069] S3, quickly placing the mixed particles with the slurry on the surface into a vacuum drying oven for vacuum drying at a temperature of 260° C. to obtain single-layer coated particles;

[0070] Repeat steps S2 and S3 until the weight of the mixed particles increases to 360 g to obtain water-absorbing resin coated particles, the particle size of the water-absorbing resin coated particles is 120 microns to 150 microns.

[0071] Preparation Example 5: Modification of polyvinyl alcohol without maltose

[0072] Preparation of water-absorbent resin coated particles

[0073] S1. Add 10 g of polyvinyl alcohol, 2 g of glycerol, and 1 g of dibutyltin dilaurate into 300 mL of hot water and stir until dissolved. The temperature of the hot water is 90° C. to obtain a coating solution.

[0074] S2, mixing 100 g of the water-absorbent resin particles prepared in Example 2 with 200 g of attapulgite to form mixed particles, and spraying the coating liquid evenly on the surface of the mixed particles;

[0075] S3, quickly placing the mixed particles with the slurry on the surface into a vacuum drying oven for vacuum drying at a temperature of 260° C. to obtain single-layer coated particles;

[0076] Repeat steps S2 and S3 until the weight of the mixed particles increases to 360 g to obtain water-absorbing resin coated particles, the particle size of the water-absorbing resin coated particles is 120 microns to 150 microns.

[0077] Preparation Example 6: No use or addition of inorganic filler

[0078] Preparation of water-absorbent resin coated particles

[0079] S1. Add 10 g of polyvinyl alcohol, 2 g of glycerol, and 1 g of dibutyltin dilaurate to 300 mL of hot water and stir until dissolved. The hot water temperature is 90° C. to obtain a coating solution. Add 4 g of maltose to the coating solution and stir to obtain a slurry.

[0080] S2, weighing 200g of water-absorbent resin particles prepared in water-absorbent resin example 2, and spraying the slurry evenly on the surface of the water-absorbent resin particles;

[0081] S3, quickly placing the water-absorbing resin particles with the slurry on the surface into a vacuum drying oven for vacuum drying at a temperature of 260° C. to obtain single-layer coated particles;

[0082] Repeat steps S2 and S3 until the weight of the mixed particles increases to 220 g to obtain water-absorbing resin coated particles, the particle size of which is 50 microns to 80 microns.

[0083] Example 1

[0084] The first step is to mix 27 parts of silicate cement, 52 parts of quartz sand, and 1.3 parts of dodecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0085] In the second step, 13 parts of the water-absorbing resin-coated particles in Preparation Example 1 are mixed with 1.4 parts of cellulose ester and 1.4 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.3 parts of vinyl acetate and 2 parts of surfactant EASYTECHST-5200 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0086] Example 2

[0087] The first step is to mix 24 parts of silicate cement, 48 parts of quartz sand, and 1.2 parts of hexadecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0088] In the second step, 12 parts of the water-absorbing resin-coated particles in Preparation Example 2 are mixed with 1.2 parts of cellulose ester and 1.2 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.2 parts of vinyl acetate and 1 part of surfactant IGEPALCO-897 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0089] Example 3

[0090] The first step is to mix 30 parts of silicate cement, 55 parts of quartz sand, and 1.5 parts of dodecanedioic acid, and then add 15 parts of water to prepare slurry 1.

[0091] In the second step, 15 parts of the water-absorbing resin-coated particles in Preparation Example 3 are mixed with 1.5 parts of cellulose ester and 1.5 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.5 parts of vinyl acetate and 3 parts of surfactant EASYTECHST-5200 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0092] Comparative Example 1

[0093] The first step is to mix 27 parts of silicate cement, 52 parts of quartz sand, and 1.3 parts of dodecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0094] In the second step, 13 parts of the water-absorbing resin-coated particles in Preparation Example 4 are mixed with 1.4 parts of cellulose ester and 1.4 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.3 parts of vinyl acetate and 2 parts of surfactant EASYTECHST-5200 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0095] Comparative Example 2

[0096] The first step is to mix 27 parts of silicate cement, 52 parts of quartz sand, and 1.3 parts of dodecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0097] In the second step, 13 parts of the water-absorbing resin-coated particles in Preparation Example 5 are mixed with 1.4 parts of cellulose ester and 1.4 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.3 parts of vinyl acetate and 2 parts of surfactant EASYTECHST-5200 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0098] Comparative Example 3

[0099] The first step is to mix 27 parts of silicate cement, 52 parts of quartz sand, and 1.3 parts of dodecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0100] In the second step, 13 parts of the water-absorbing resin-coated particles in Preparation Example 6 are mixed with 1.4 parts of cellulose ester and 1.4 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.3 parts of vinyl acetate and 2 parts of surfactant EASYTECHST-5200 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0101] Comparative Example 4: Preparation without using water-absorbing resin coated particles, but using silicone resin particles

[0102] The first step is to mix 27 parts of silicate cement, 52 parts of quartz sand, and 1.3 parts of dodecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0103] In the second step, 13 parts of the silicone resin particles in Preparation Example 1 are mixed with 1.4 parts of cellulose ester and 1.4 parts of cellulose ether, and then added to slurry 1 and stirred evenly to obtain slurry 2. 1.3 parts of vinyl acetate and 2 parts of surfactant EASYTECHST-5200 are placed in 5 parts of water, and slowly added to slurry 2 and stirred to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0104] Comparative Example 5: No Cellulose Ester or Cellulose Ether Used

[0105] The first step is to mix 27 parts of silicate cement, 52 parts of quartz sand, and 1.3 parts of dodecanedioic acid, and then add 10 parts of water to prepare a slurry 1.

[0106] The second step is to add 13 parts of the water-absorbing resin-coated particles in Preparation Example 1 into slurry 1 and stir evenly to obtain slurry 2, place 1.3 parts of vinyl acetate and 2 parts of surfactant EASYTECH ST-5200 in 15-20 parts of water, and slowly add them into slurry 2 and stir to obtain a waterproof adhesive for wet-laid waterproof membrane.

[0107] Experiments and data

[0108] The wet-laid waterproof membrane waterproof adhesive prepared in Examples 1 to 3 and Comparative Examples 1 to 5 was used to lay the wet-laid waterproof membrane with a moistened cement layer as a substrate. After curing for 12 days, the peel strength was tested, and a water seepage test was performed after artificial cracks were generated, and the waterproof depth was measured.

[0109] Water seepage test: The membrane and cement base are vibrated for 48 hours, and then the surface of the membrane is scratched with a blade. The crack length is 5 cm. The crack is sprayed with water for 7 days to test the peeling strength and water seepage depth.

[0110] The test method standards are as follows:

[0111] The test standard for peel strength is in accordance with the method of JC / T863-2011, with the unit of N / mm;

[0112] The waterproof depth is calculated according to the distance water seeps down after a fixed seepage time, in cm;

[0113] The data are shown in Table 1 below:

[0114]

[0115] The peel strength of each embodiment and each comparative example is plotted as a line graph to observe the degree of decrease in the peel strength. Figure 1 shown.

[0116] analyze

[0117] According to the data in Table 1, it can be seen that the peel strength decrease ratio of the wet-laid waterproof membrane waterproof adhesive prepared in Examples 1 to 3 of the present application before and after the water seepage test is about 12%, and it has strong water resistance and peel strength. In the 7d water spray test, the water seepage depth does not exceed 3mm. The adhesive itself has a strong waterproof ability, which can block cement cracks and effectively prevent water molecules from seeping in.

[0118] The wet-laid waterproof roll waterproof adhesive prepared in Comparative Example 1 does not use polyvinyl alcohol to coat the water-absorbing resin particles, but uses a hydrophobic coating to coat the water-absorbing resin. The rest is the same as Example 1, and the peeling strength shown in Comparative Example 1 is reduced by 30%, and the water penetration depth has reached 21 mm. All data are not as good as the data of Example 1 of the present application, indicating that the use of polyvinyl alcohol to coat the water-absorbing resin particles in the present application can effectively not affect the absorption of water molecules by the water-absorbing resin particles after subsequent maintenance and vibration treatment, and can better maintain the water absorption effect of the water-absorbing resin particles.

[0119] The wet-laid waterproofing membrane waterproofing adhesive prepared in Comparative Example 2 did not use maltose to transform polyvinyl alcohol, and the remaining steps were the same as in Example 1. The peel strength of Comparative Example 2 decreased by 33%, but the water seepage depth was 11 mm, the peel strength decreased more, and the water seepage depth was moderate, indicating that the transformation of polyvinyl alcohol by maltose can significantly enhance the adhesion effect between the polymer molecules and the cement gaps, thereby enhancing the adhesion effect on the membrane, making the membrane difficult to peel off. The water seepage depth indicates that the water-absorbing resin particles have a certain ability to hinder the infiltration of water molecules after absorbing water and swelling, and can greatly enhance the waterproof effect when combined with maltose.

[0120] The wet-laid waterproof membrane waterproof adhesive prepared in Comparative Example 3 did not use or add inorganic fillers, and the remaining steps were the same as Example 1. The results showed that the peel strength of Comparative Example 3 decreased by 19%, and the water seepage depth was 12.4, and the water seepage was relatively serious, indicating that the inorganic filler has a certain protective effect on the water-absorbing resin particles and will not cause them to absorb water and expand in advance, thereby ensuring that after the cement is solidified, the cement gaps and capillary structures are small, and no excessive penetration will occur during the subsequent water seepage process, which is convenient for timely waterproofing.

[0121] The wet-laid waterproof membrane waterproof adhesive prepared in Comparative Example 4 does not use water-absorbing resin coated particles, but uses silicone resin particles. The remaining steps are the same as those in Example 1. The data show that the peel strength of Comparative Example 4 decreases by 32%, and the water penetration depth is 18.9 mm, which proves that the presence of water-absorbing resin particles has the greatest impact on the wet-laid waterproof membrane waterproof adhesive. The presence of water-absorbing resin particles can not only lock the infiltrated water, but also the hydrogel formed after absorbing water blocks the gaps and capillaries, further preventing the infiltration of water, and has extremely strong waterproof performance. The extrusion effect brought about by its expansion also enhances the adhesion performance, so that the maltose component contacts and adheres to each component, thereby enhancing the peel strength.

[0122] The wet-laid waterproof membrane waterproof adhesive prepared in Comparative Example 5 does not use cellulose ester and cellulose ether, and the remaining steps are the same as Example 1. The data show that the peel strength of Comparative Example 5 decreases by 15%, and the water penetration depth is as small as 4.8 mm, which shows that the presence of cellulose ester and cellulose ether can slightly improve the peel strength and waterproof ability, and that the presence of cellulose ester and cellulose ether can effectively reduce the capillary structure and the shrinkage of cement, thereby facilitating the discharge of tiny bubbles and not forming adhesive holes. On the other hand, the peel strength is enhanced, and sufficient capillary structure will also enable the water-absorbing resin particles to absorb enough water molecules to fill the cracks and capillaries, preventing water from seeping in and improving the waterproof ability.

[0123] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A waterproof adhesive for wet-laid waterproof roll material, characterized in that: The invention is prepared from the following raw materials in parts by weight: 24-30 parts of silicate cement, 48-55 parts of quartz sand, 15-20 parts of water, 1-3 parts of surfactant, 1.2-1.5 parts of long-chain polyacid, 1.2-1.5 parts of cellulose ester, 1.2-1.5 parts of cellulose ether, 1.2-1.5 parts of vinyl acetate, and 12-15 parts of water-absorbing resin-coated particles; The preparation method of the water-absorbing resin coated particles comprises the following steps: S1, adding polyvinyl alcohol, glycerol and a stabilizer into hot water and stirring until dissolved to obtain a coating liquid, adding maltose into the coating liquid, stirring and preparing a slurry; S2, mixing the water-absorbing resin particles and the inorganic filler in a weight ratio of 1:1.5-3 to form mixed particles, and spraying the slurry evenly on the surface of the mixed particles; S3, vacuum drying the mixed particles containing the slurry on the surface to obtain single-layer coated particles; Repeating steps S2 and S3 to obtain water-absorbing resin coated particles, wherein the mass increase ratio of the water-absorbing resin coated particles is 10%-30%; The weight ratio of the polyvinyl alcohol, glycerol, maltose and stabilizer is 5:0.75-1.5:1-3:0.05-2; The stabilizer in S1 is one of dibutyltin dilaurate or dibutyltin dimaleate, and the inorganic filler in S2 is one of montmorillonite or attapulgite.

2. A waterproof adhesive for wet-laid waterproof roll material according to claim 1, characterized in that: The finished particle size of the water-absorbing resin coated particles is between 75 microns and 200 microns.

3. A waterproof adhesive for wet-laid waterproof roll material according to claim 1, characterized in that: The preparation steps of the water-absorbing resin are as follows: A1. Mix starch and water at a solid-liquid ratio of 1 g:20 mL, and heat in an oxygen-free environment to perform gelatinization reaction; A2, mixing the cerium nitrate solution with acrylonitrile to obtain a cerium nitrate solution of acrylonitrile, and adding the cerium nitrate solution containing acrylonitrile to the gelatinized starch solution for grafting reaction; A3, using dilute sodium hydroxide to adjust the pH value to neutral and heating to remove unreacted acrylonitrile, adding 2 mol / L sodium hydroxide solution to carry out saponification reaction; A4. Use acetic acid to adjust the pH value to neutral, add ethanol for precipitation, filter and crush to obtain a water-absorbing resin.

4. A waterproof adhesive for wet-laid waterproof roll material according to claim 3, characterized in that: The mass ratio of starch to acrylonitrile in the gelatinization reaction is 1:1, the gelatinization reaction temperature is 90° C., and the reaction time is 30-60 min.

5. The waterproof adhesive for wet-laid waterproof roll material according to claim 3, characterized in that: The mass ratio of the cerium nitrate to the acrylonitrile is 3-8:100, the concentration of the cerium nitrate solution is 0.1 g / mL, and the solvent for preparing the cerium nitrate solution is 1 mol / L nitric acid.

6. A waterproof adhesive for wet-laid waterproofing membrane according to claim 1, characterized in that: The long-chain polyacid is one of dodecanedioic acid and hexadecanedioic acid, and the surfactant is one of EASYTECH ST-5200 and IGEPAL CO-897.

7. A method for preparing a waterproof adhesive for wet-laid waterproof roll material according to any one of claims 1 to 6, characterized in that: The following steps are involved: The first step is to mix silicate cement, quartz sand and long-chain polyacid, and then add water to prepare a slurry 1; In the second step, the water-absorbing resin coated particles are mixed with cellulose ester and cellulose ether, and then added into slurry 1 and stirred evenly to obtain slurry 2; vinyl acetate and surfactant are placed in the remaining water, and slowly added into slurry 2 and stirred to obtain waterproof adhesive for wet-laid waterproof membrane.

8. The method for preparing the waterproof adhesive for wet-laid waterproof coiled material according to claim 7, characterized in that: The volume ratio of the water used in the first step to the water used in the second step is 2-3:1.

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