Anti-leakage cement fire pool water expansion water stop

Abstract

The present invention relates to a water-swelling waterstop strip for leak-proof cement fire-fighting pools, belonging to the technical field of rubber expansion waterstop strips. The waterstop strip comprises, by weight, 30-40 parts of chloroprene rubber, 50-60 parts of ethylene propylene diene monomer (EPDM) rubber, 10-20 parts of xanthan gum, 20-30 parts of sodium bentonite, 30-50 parts of a high molecular weight water-absorbing resin, 8-10 parts of a tackifying resin, 1-2 parts of silica sol, 1-3 parts of a plasticizer, 3-5 parts of a vulcanizing agent, 0.5-1 parts of an antioxidant, and 10-20 parts of a filler. The water-swelling waterstop strip for leak-proof cement fire-fighting pools has the advantages of good water absorption and expansion and high mechanical properties.

Description

Technical Field

[0001] The invention belongs to the technical field of rubber expansion waterstop strips, and in particular relates to water-expanding waterstop strips for leak-proof cement fire-fighting pools, which have the advantages of good water absorption and expansion and high mechanical properties. Background Art

[0002] Water-swelling waterstops are a unique new rubber product. When joints or construction joints shift, creating gaps beyond the material's elastic range, the rubber expands 2-3 times its original size upon contact with water, filling all irregularities, cavities, and gaps in the joint while generating tremendous contact pressure to completely prevent leakage. Using water-swelling rubber as a leak-proof, sealing, and waterstop material not only saves on material usage but also eliminates the elastic fatigue that can occur with conventional elastic materials due to excessive compression, resulting in a more reliable waterproofing effect.

[0003] With the development of science and technology and the widespread application of water-swelling strips, higher requirements are currently being placed on the water absorption and expansion properties and mechanical properties of water-swelling waterstop strips. Summary of the Invention

[0004] The purpose of the invention is to provide a water-swelling waterstop strip for anti-leakage cement fire-fighting pools with good water absorption and expansion properties and high mechanical properties.

[0005] The present invention adopts the following technical solutions to achieve its purpose:

[0006] The anti-leakage cement fire pool water-expanding waterstop comprises, by weight, 30-40 parts of chloroprene rubber, 50-60 parts of EPDM rubber, 10-20 parts of xanthan gum, 20-30 parts of sodium bentonite, 30-50 parts of high molecular water-absorbing resin, 8-10 parts of tackifying resin, 1-2 parts of silica sol, 1-3 parts of plasticizer, 3-5 parts of vulcanizing agent, 0.5-1 part of antioxidant and 10-20 parts of filler;

[0007] The polymer water-absorbing resin is prepared by the following method:

[0008] A. Dissolve 10 parts of acrylic acid in deionized water, adjust the neutralization degree to 70-85% in an ice-water bath, add 0.2-0.3 parts of carboxymethyl chitosan with a deacetylation degree of 70-80%, and stir to dissolve to obtain a premixed solution;

[0009] B. dissolving 0.1-0.15 parts of polyvinyl alcohol in deionized water at 80-90°C and stirring to obtain a polyvinyl alcohol solution;

[0010] C. Under nitrogen protection, add 0.2-0.3 parts of potassium persulfate and 0.04-0.05 parts of N,N-methylenebisacrylamide to the premixed solution obtained in step A, then add the polyvinyl alcohol solution obtained in step B dropwise thereto for reaction, controlling the addition time to be 2-4 hours. After stirring, heat-insulate at 50-60°C for 30-40 minutes, filter, dry and crush to obtain a super absorbent resin.

[0011] In step B, the polyvinyl alcohol is composed of polyvinyl alcohol with a degree of polymerization of 500-800 and polyvinyl alcohol with a degree of polymerization of 1500-2000 in a mass ratio of (0.1-0.2):1.

[0012] The tackifying resin is selected from one or any combination of phenolic resin, coumarone resin and terpene resin.

[0013] The plasticizer is one of dioctyl adipate, dibutyl phthalate and paraffin oil.

[0014] The vulcanizing agent is selected from one of 1,2-ethylenethiourea, sulfur and dicumyl peroxide.

[0015] The antioxidant is selected from one or any combination of antioxidant RD, antioxidant MB, antioxidant ZMMBI and antioxidant NBC.

[0016] The filler is one or any combination of carbon nanotubes, zinc oxide, magnesium oxide, carbon black and silica.

[0017] The beneficial effects of the present invention are:

[0018] The water-expanding waterstop strip for the anti-leakage cement fire-fighting pool of the present invention has the advantages of high expansion rate, low mass loss rate after immersion in water, and good mechanical properties.

[0019] The high molecular water-absorbing resin prepared by the present invention can improve the polarity of the water stop strip, and cooperate with sodium bentonite and chloroprene rubber to improve the water expansion of the water stop strip; then by adding silica sol and chloroprene rubber, EPDM rubber and xanthan gum to form a non-polar continuous phase, the macromolecular networks cross-penetrate each other, thereby improving the bonding degree of the two phases and avoiding the large-scale precipitation of hydrophilic components after immersion in water; the addition of the silica sol of the present invention can also improve the adhesion between the water stop strip and cement after water absorption, thereby reducing the stress difference.

[0020] The high-molecular water-absorbing resin prepared by the method of the invention has good water-retaining property under pressure and high water absorption rate. DETAILED DESCRIPTION

[0021] The present invention is described in detail below with reference to specific embodiments and performance experiments. It is apparent that the embodiments described are only a portion of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention. 1. Specific embodiments

[0023] Example 1

[0024] Preparation of polymer water-absorbing resin:

[0025] A. Dissolve 10 parts of acrylic acid in deionized water, adjust the neutralization degree to 70% in an ice-water bath, add 0.2 parts of carboxymethyl chitosan with a deacetylation degree of 71%, and stir to dissolve to obtain a premixed solution;

[0026] B. dissolving 0.01 parts of polyvinyl alcohol having a degree of polymerization of 500 and 0.09 parts of polyvinyl alcohol having a degree of polymerization of 1700 in deionized water at 80° C. and stirring to obtain a polyvinyl alcohol solution;

[0027] C. Under nitrogen protection, 0.2 parts of potassium persulfate and 0.04 parts of N,N-methylenebisacrylamide were added to the premixed solution obtained in step A, and then the polyvinyl alcohol solution in step B was added dropwise thereto for reaction. The addition time was controlled to be 2 hours. After stirring, the mixture was kept warm at 54°C for 40 minutes, filtered, dried and crushed to obtain a super absorbent resin.

[0028] Anti-leakage cement fire pool water-swelling waterstop: prepare 30 parts of neoprene, 50 parts of EPDM rubber, 10 parts of xanthan gum, 20 parts of sodium bentonite, 35 parts of high molecular water-absorbing resin, 9 parts of phenolic resin, 1 part of silica sol, 2 parts of dioctyl adipate, 4 parts of diisopropylbenzene peroxide, 0.5 parts of antioxidant RD, 5 parts of carbon nanotubes, 7 parts of zinc oxide, and 6 parts of silica.

[0029] Example 2

[0030] Preparation of polymer water-absorbing resin:

[0031] A. Dissolve 10 parts of acrylic acid in deionized water, adjust the neutralization degree to 75% in an ice-water bath, add 0.25 parts of carboxymethyl chitosan with a deacetylation degree of 73%, and stir to dissolve to obtain a premixed solution;

[0032] B. dissolving 0.025 parts of polyvinyl alcohol having a degree of polymerization of 600 and 0.125 parts of polyvinyl alcohol having a degree of polymerization of 1800 in deionized water at 85° C. and stirring to obtain a polyvinyl alcohol solution;

[0033] C. Under nitrogen protection, 0.25 parts of potassium persulfate and 0.05 parts of N,N-methylenebisacrylamide were added to the premixed solution obtained in step A, and then the polyvinyl alcohol solution in step B was added dropwise thereto for reaction. The addition time was controlled to be 3 hours. After stirring, the mixture was kept at 50°C for 36 minutes, filtered, dried and crushed to obtain a super absorbent resin.

[0034] Anti-leakage cement fire pool water-swelling waterstop: prepare 32 parts of chloroprene rubber, 60 parts of EPDM rubber, 18 parts of xanthan gum, 30 parts of sodium bentonite, 50 parts of high molecular water-absorbing resin, 10 parts of coumarone resin, 2 parts of silica sol, 1 part of dibutyl phthalate, 3 parts of 1,2-ethylenethiourea, 1 part of antioxidant MB, 4 parts of magnesium oxide, and 8 parts of carbon black in parts by weight.

[0035] Example 3

[0036] Preparation of polymer water-absorbing resin:

[0037] A. Dissolve 10 parts of acrylic acid in deionized water, adjust the neutralization degree to 80% in an ice-water bath, add 0.23 parts of carboxymethyl chitosan with a deacetylation degree of 76%, and stir to dissolve to obtain a premixed solution;

[0038] B. dissolving 0.011 parts of polyvinyl alcohol having a degree of polymerization of 800 and 0.109 parts of polyvinyl alcohol having a degree of polymerization of 1500 in deionized water at 90° C. and stirring to obtain a polyvinyl alcohol solution;

[0039] C. Under nitrogen protection, 0.3 parts of potassium persulfate and 0.04 parts of N,N-methylenebisacrylamide were added to the premixed solution obtained in step A, and then the polyvinyl alcohol solution in step B was added dropwise thereto for reaction. The addition time was controlled to be 4 hours. After stirring, the mixture was kept warm at 55°C for 30 minutes, filtered, dried and crushed to obtain a super absorbent resin.

[0040] Anti-leakage cement fire pool water-swelling waterstop: prepare 40 parts of chloroprene rubber, 55 parts of EPDM rubber, 20 parts of xanthan gum, 25 parts of sodium bentonite, 40 parts of high molecular water-absorbing resin, 8 parts of phenolic resin, 2 parts of silica sol, 3 parts of paraffin oil, 4 parts of sulfur, 1 part of antioxidant NBC, 5 parts of zinc oxide, 8 parts of carbon black, and 7 parts of silica.

[0041] Example 4

[0042] Preparation of polymer water-absorbing resin:

[0043] A. Dissolve 10 parts of acrylic acid in deionized water, adjust the neutralization degree to 85% in an ice-water bath, add 0.3 parts of carboxymethyl chitosan with a deacetylation degree of 80%, and stir to dissolve to obtain a premixed solution;

[0044] B. dissolving 0.01 parts of polyvinyl alcohol having a degree of polymerization of 700 and 0.09 parts of polyvinyl alcohol having a degree of polymerization of 2000 in deionized water at 85° C. and stirring to obtain a polyvinyl alcohol solution;

[0045] C. Under nitrogen protection, 0.2 parts of potassium persulfate and 0.05 parts of N,N-methylenebisacrylamide were added to the premixed solution obtained in step A, and then the polyvinyl alcohol solution in step B was added dropwise thereto for reaction. The addition time was controlled to be 3 hours. After stirring, the mixture was kept warm at 60°C for 38 minutes, filtered, dried and crushed to obtain a super absorbent resin.

[0046] Anti-leakage cement fire pool water-swelling waterstop: prepare 42 parts of chloroprene rubber, 56 parts of EPDM rubber, 15 parts of xanthan gum, 24 parts of sodium bentonite, 38 parts of high molecular water-absorbing resin, 9 parts of terpene resin, 1 part of silica sol, 2 parts of dibutyl phthalate, 5 parts of 1,2-ethylene thiourea, 0.5 parts of antioxidant ZMMBI, 5 parts of zinc oxide, 7 parts of magnesium oxide, and 8 parts of carbon black in parts by weight.

[0047] Example 5

[0048] The difference from Example 3 is that 0.12 parts of polyvinyl alcohol with a degree of polymerization of 1500 is used in the preparation of the high molecular water-absorbing resin.

[0049] Example 6

[0050] The difference from Example 3 is that 0.12 parts of polyvinyl alcohol with a degree of polymerization of 800 is used in the preparation of the high molecular water-absorbing resin.

[0051] The anti-leakage cement fire pool water-swelling water stop strip is prepared by the following method:

[0052] According to the formula, chloroprene rubber, EPDM rubber and xanthan gum are weighed and mixed, and the mixture is plasticized for 3 minutes. Then, sodium bentonite, super absorbent resin and plasticizer are added and the mixture is plasticized for 10 minutes. Then, vulcanizing agent, antioxidant, tackifying resin, silica sol and filler are added and the mixture is plasticized for 5 minutes to obtain a rubber mixture. The rubber mixture is extruded into shape and vulcanized on a flat vulcanizing press to obtain a water-swelling waterstop strip for a leak-proof cement fire pool.

[0053] Comparative Example 1

[0054] The difference from Example 3 is that the high molecular water-absorbing resin is sodium polyacrylate.

[0055] Comparative Example 2

[0056] The difference from Example 3 is that no silica sol is added.

[0057] 2. Performance Experiment

[0058] 1. Water absorption expansion rate and water pressure resistance test

[0059] The water absorption expansion rate and water resistance pressure were determined according to the method in the JGT 141-2001 Bentonite Rubber Water-Swellable Waterstop Standard.

[0060] Table 1

[0061] project 4h water absorption expansion ratio / % Maximum water absorption expansion ratio / % Water pressure resistance / MPa Example 1 223 586.6 1.9 Example 2 234 597.8 2.0 Example 3 245 612.4 2.1 Example 4 231 603.2 2.0 Example 5 216 532.6 1.8 Example 6 214 514.0 1.8 Comparative Example 1 207 442.3 1.6 Comparative Example 2 234 605.1 2.1

[0062] As can be seen from Table 1, the bentonite rubber water-swelling waterstop strip obtained by adding the super absorbent resin prepared by the present invention has improved water swelling rate and water pressure resistance; by comparing Example 3 with Comparative Example 2, it can be seen that the addition of silica sol has no negative impact on water swelling property and water pressure resistance; by comparing the effects of Examples 1-4 with Examples 5-6, it can be seen that the super absorbent resin prepared by compounding polyvinyl alcohol with a degree of polymerization of 500-800 and polyvinyl alcohol with a degree of polymerization of 1500-2000 in a mass ratio of (0.1-0.2):1 is further improved in water swelling property and water pressure resistance after being applied to the bentonite rubber water-swelling waterstop strip.

[0063] 2. Weight loss rate experiment

[0064] The bentonite rubber water-swellable waterstop obtained in the example was cut into 30 mm × 10 mm × 10 mm samples, and the mass before immersion was measured. The samples were then immersed in tap water until saturated with water, dried at 50° C. to constant weight, and the weight loss rate was measured. The weight loss rate was calculated according to the following formula:

[0065] △ M(%)=(M0-M1) / M0×100%

[0066] Where: △ M—weight loss rate of waterstop;

[0067] M0—the quality of the waterstop before immersion in water;

[0068] M1—The mass of the waterstop after absorbing water and drying.

[0069] Table 2

[0070]

[0071] It can be seen from Table 2 that the weight loss rate of the bentonite rubber water-swelling waterstop obtained by compounding the super absorbent resin prepared by the present invention with silica sol is significantly reduced.

[0072] 3. Mechanical properties test

[0073] Heat resistance, low temperature flexibility, and water resistance were determined according to the methods in the JGT 141-2001 Bentonite Rubber Water-Swellable Waterstop standard; tensile strength and elongation at break were determined according to the standard GB / T528-2009.

[0074] Table 3

[0075]

Claims

1. Anti-leakage cement fire pool water expansion water stop strip, characterized by: Calculated by weight, it includes 30-40 parts of chloroprene rubber, 50-60 parts of EPDM rubber, 10-20 parts of xanthan gum, 20-30 parts of sodium bentonite, 30-50 parts of high molecular water-absorbing resin, 8-10 parts of tackifying resin, 1-2 parts of silica sol, 1-3 parts of plasticizer, 3-5 parts of vulcanizing agent, 0.5-1 part of antioxidant and 10-20 parts of filler; The polymer water-absorbing resin is prepared by the following method: A. Dissolve 10 parts of acrylic acid in deionized water, adjust the neutralization degree to 70-85% in an ice-water bath, add 0.2-0.3 parts of carboxymethyl chitosan with a deacetylation degree of 70-80%, and stir to dissolve to obtain a premixed solution; B. dissolving 0.1-0.15 parts of polyvinyl alcohol in deionized water at 80-90° C. and stirring to obtain a polyvinyl alcohol solution; the polyvinyl alcohol is composed of polyvinyl alcohol with a degree of polymerization of 500-800 and polyvinyl alcohol with a degree of polymerization of 1500-2000 in a mass ratio of (0.1-0.2):1; C. Under nitrogen protection, add 0.2-0.3 parts of potassium persulfate and 0.04-0.05 parts of N,N-methylenebisacrylamide to the premixed solution obtained in step A, then add the polyvinyl alcohol solution obtained in step B dropwise thereto for reaction, controlling the addition time to be 2-4 hours. After stirring, heat-insulate at 50-60°C for 30-40 minutes, filter, dry and crush to obtain a super absorbent resin.

2. The anti-leakage cement fire pool water-swelling water stop strip according to claim 1, characterized in that: The tackifying resin is selected from one or any combination of phenolic resin, coumarone resin and terpene resin.

3. The anti-leakage cement fire pool water-swelling water stop strip according to claim 1, characterized in that: The plasticizer is one of dioctyl adipate, dibutyl phthalate and paraffin oil.

4. The anti-leakage cement fire pool water-swelling water stop strip according to claim 1, characterized in that: The vulcanizing agent is selected from one of 1,2-ethylenethiourea, sulfur and dicumyl peroxide.

5. The anti-leakage cement fire pool water-swelling water stop strip according to claim 1, characterized in that: The antioxidant is selected from one or any combination of antioxidant RD, antioxidant MB, antioxidant ZMMBI and antioxidant NBC.

6. The anti-leakage cement fire pool water-swelling water stop strip according to claim 1, characterized in that: The filler is one or any combination of carbon nanotubes, zinc oxide, magnesium oxide, carbon black and silica.

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