A rubber dam composite material having excellent air tightness and long life and a method for manufacturing the same

Abstract

The present application provides a rubber dam composite material with excellent air tightness and long service life, which is prepared from the following raw materials: 100 parts of raw rubber, 40-100 parts of reinforcing filler, 2-15 parts of activator, 4-30 parts of plasticizer, 0-10 parts of magnesium oxide, 1.0-10.0 parts of accelerator, 0.5-10 parts of vulcanizing agent and 0.5-10 parts of adhesive; the raw rubber comprises butyl rubber and a second rubber component in a mass ratio of (10-90):(10-90), the second rubber component is ethylene-propylene-diene rubber and / or natural rubber; and the adhesive is selected from tackifying resin and modified phenolic resin. The rubber dam composite material has excellent aging resistance and ultraviolet resistance, and excellent adhesion between different rubber layers (or with polyester or nylon impregnated sailcloth) due to the combined action of the above-mentioned specific types and amounts of raw materials.

Description

Technical Field

[0001] This invention belongs to the field of rubber composite material technology, and particularly relates to a rubber dam composite material with excellent airtightness and long service life and its preparation method. Background Technology

[0002] A rubber dam, also known as a rubber sluice gate, is a bag-shaped water-retaining dam made of high-strength synthetic fiber fabric as the load-bearing skeleton, coated with rubber on both the inside and outside as protective layers. This fabric is then anchored to a base plate to form a closed dam bag. It is inflated using water (or air) through inflation and deflation pipelines. Rubber dams are divided into water-inflated and air-inflated types. The dam crest can overflow, and the dam height can be adjusted as needed to control the upstream water level, thus providing benefits such as irrigation, power generation, navigation, flood control, and tide prevention.

[0003] The main raw materials used in existing rubber dams are EPDM rubber and natural rubber. Due to the poor air / water tightness of the materials themselves, the air retention performance of the rubber dams is insufficient, which leads to a decrease in dam height, reduced water-blocking performance or failure to block water, and even safety hazards. Therefore, it is necessary to check the air pressure from time to time. On the other hand, because natural rubber has poor aging resistance, a certain amount of antioxidant needs to be added during the production process to improve the aging resistance of the rubber dams, which wastes a lot of manpower, material resources and financial resources. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a rubber dam composite material with excellent airtightness and long service life and a method for preparing the same. The rubber dam composite material has excellent aging resistance and UV resistance, and excellent adhesion between different adhesive layers (or with polyester or nylon impregnated canvas).

[0005] This invention provides a rubber dam composite material with excellent airtightness and long service life, and the raw materials for its preparation include the following components:

[0006] 100 parts raw rubber, 40-100 parts reinforcing filler, 2-15 parts activator, 4-30 parts plasticizer, 0-10 parts magnesium oxide, 1.0-10.0 parts accelerator, 0.5-10 parts vulcanizing agent and 0.5-10.0 parts adhesive;

[0007] The raw rubber comprises butyl rubber and a second rubber component in a mass ratio of (10-90):(10-90), wherein the second rubber component is ethylene propylene diene monomer (EPDM) rubber and / or natural rubber.

[0008] The adhesive is selected from tackifying resins and modified phenolic resins.

[0009] Preferably, the tackifying resin is the super tackifying resin Koresin;

[0010] The modified phenolic resin is modified resorcinol formaldehyde resin B-16S.

[0011] Preferably, the reinforcing filler is selected from one or more of carbon black, pyrolysis carbon black, calcium carbonate, calcium sulfate, dolomite powder, kaolin, clay, montmorillonite, barium sulfate, talc, magnesium carbonate, silica, magnesium silicate, graphene, and cellulose bio-based materials.

[0012] Preferably, the activator is selected from one or more of zinc oxide, stearic acid, lead oxide, and titanium dioxide;

[0013] The plasticizer is selected from one or more of naphthenic oils, aromatic oils, paraffin oils, butyl oleate, and dibutyl phthalate;

[0014] The accelerator is selected from one or more of the following: thiazole accelerators, thiuram accelerators, dithiocarbamate accelerators, xanthate accelerators, guanidine accelerators, aldehyde amine accelerators, sulfenamide accelerators, and thiourea accelerators.

[0015] The vulcanizing agent is selected from sulfur and / or peroxides.

[0016] This invention provides a method for preparing the rubber dam composite material with excellent airtightness and long service life as described in the above technical solution, comprising the following steps:

[0017] The raw rubber is mixed, and reinforcing fillers, adhesives, magnesium oxide and plasticizers are added and mixed again. When the temperature reaches 110-150℃, the rubber is discharged to obtain a first-stage masterbatch.

[0018] After cooling the first stage of masterbatch, it is left to stand, then mixed with vulcanizing agent, accelerator and activator and continued to be mixed. When the temperature reaches 90-130℃, the rubber is discharged to obtain the second stage final rubber.

[0019] After the two-stage final rubber compound is sheeted and left to stand, a rubber dam composite material is obtained.

[0020] Preferably, the raw rubber includes natural rubber, which is masticated before use until the Mooney viscosity ML(1+4)100 value is 40 to 70.

[0021] Preferably, reinforcing fillers, binders, magnesium oxide and plasticizers are added and the mixture is further mixed at 40-80°C for 4-8 minutes;

[0022] The temperature of the first stage of masterbatch cooling is below 80°C, and the standing time is greater than 30 minutes.

[0023] The mixture is then further mixed with the vulcanizing agent, accelerator, and activator, and the mixing time continues for 1 to 3 minutes.

[0024] The temperature at which the two-stage final rubber is sheeted is 20-30°C, and the time is 18-24 hours.

[0025] Preferably, the vulcanization temperature is 130–180°C, the vulcanization pressure is 20–40 tons, and the time is 5–60 minutes.

[0026] This invention provides a rubber dam composite material with excellent airtightness and long service life. The raw materials for preparation include the following components: 100 parts raw rubber, 40-100 parts reinforcing filler, 2-15 parts activator, 4-30 parts plasticizer, 0-10 parts magnesium oxide, 1.0-10.0 parts accelerator, 0.5-10 parts vulcanizing agent, and 0.5-10.0 parts binder. The raw rubber comprises a butyl rubber and a second rubber component in a mass ratio of (10-90):(10-90), wherein the second rubber component is EPDM rubber and / or natural rubber. The binder is selected from tackifying resins and modified phenolic resins. Under the combined effect of the above-mentioned specific types and amounts of raw materials, the above-mentioned rubber dam composite material exhibits excellent aging resistance and UV resistance, and excellent adhesion between different rubber layers (or with polyester or nylon-impregnated canvas). Detailed Implementation

[0027] This invention provides a rubber dam composite material with excellent airtightness and long service life, and the raw materials for its preparation include the following components:

[0028] 100 parts raw rubber, 40-100 parts reinforcing filler, 2-15 parts activator, 4-30 parts plasticizer, 0-10 parts magnesium oxide, 1.0-10.0 parts accelerator, 0.5-10 parts vulcanizing agent and 0.5-10.0 parts adhesive;

[0029] The raw rubber comprises butyl rubber and a second rubber component in a mass ratio of (10-90):(10-90), wherein the second rubber component is ethylene propylene diene monomer (EPDM) rubber and / or natural rubber.

[0030] The adhesive is a tackifying resin and a modified phenolic resin.

[0031] To achieve excellent gas retention, aging resistance, ozone resistance, and UV resistance in rubber dam composite materials, this invention employs butyl rubber and uses or replaces a portion of EPDM (or natural rubber). However, the introduction of butyl rubber results in slightly weaker interlayer adhesion between butyl rubber and other rubber dam materials. To address this, this invention introduces a specific type of adhesive, thus solving the limitation on the application of butyl rubber in rubber dams and air shield dams. This significantly improves the gas and water retention performance of rubber dams without affecting interlayer adhesion, which is of great economic significance for realizing the application of butyl rubber in rubber dams.

[0032] The raw materials for preparing the composite material provided by this invention include 100 parts of raw rubber; the raw rubber comprises a butyl rubber and a second rubber component in a mass ratio of (10-90):(10-90), wherein the second rubber component is ethylene propylene diene monomer (EPDM) rubber and / or natural rubber. The butyl rubber used in this invention is selected from one or more of ordinary butyl rubber, brominated butyl rubber, chlorinated butyl rubber, star-branched butyl rubber, and halogenated butyl rubber, preferably brominated butyl rubber. The second rubber component is EPDM rubber and / or natural rubber.

[0033] The raw materials for preparing the composite material provided by the present invention include 40 to 100 parts of reinforcing filler; the reinforcing filler is selected from one or more of carbon black, pyrolysis carbon black, calcium carbonate, calcium sulfate, dolomite powder, clay, montmorillonite, barium sulfate, talc, magnesium carbonate, silica, magnesium silicate, graphene and cellulose bio-based.

[0034] The raw materials for preparing the composite material provided by the present invention include 2 to 15 parts of an activator, wherein the activator is selected from one or more of zinc oxide, stearic acid, lead oxide and titanium dioxide;

[0035] The raw materials for preparing the composite material provided by the present invention include 4 to 30 parts of plasticizer, wherein the plasticizer is selected from one or more of naphthenic oil, aromatic oil, paraffin oil, butyl oleate, and dibutyl phthalate;

[0036] The raw materials for preparing the composite material provided by this invention include 0 to 10 parts of magnesium oxide.

[0037] The raw materials for preparing the composite material provided by the present invention include 1.0 to 10.0 parts of accelerator, wherein the accelerator is selected from one or more of thiazole accelerators, thiuram accelerators, dithiocarbamate accelerators, xanthate accelerators, guanidine accelerators, aldehyde amine accelerators, sulfenamide accelerators and thiourea accelerators.

[0038] The raw materials for preparing the composite material provided by the present invention include 0.5 to 10 parts of a vulcanizing agent; the vulcanizing agent is selected from sulfur and / or peroxide.

[0039] The raw materials for preparing the composite material provided by this invention include 0.5 to 10.0 parts of an adhesive, wherein the adhesive is selected from tackifying resins and modified phenolic resins; the tackifying resin is selected from the super tackifying resin Koresin; the modified phenolic resin is selected from modified resorcinol-formaldehyde resin B-16S; the mass ratio of the tackifying resin to the modified phenolic resin is 0.5 to 10: 0.5 to 8. This invention, by selecting the above-mentioned specific types of modified phenolic resin adhesives, improves the adhesion between butyl rubber and other rubbers (as well as polyester or nylon impregnated canvas), extends service life, and ensures the gas retention, aging resistance, ozone resistance, and UV resistance of the rubber dam.

[0040] This invention provides a method for preparing the rubber dam and air shield dam composite material with excellent airtightness and long service life described in the above technical solution, comprising the following steps:

[0041] The raw rubber is mixed, and reinforcing fillers, adhesives, magnesium oxide and plasticizers are added and mixed again. When the temperature reaches 110-150℃, the rubber is discharged to obtain a first-stage masterbatch.

[0042] After cooling the first stage of masterbatch, it is left to stand, then mixed with vulcanizing agent, accelerator and activator and continued to be mixed. When the temperature reaches 90-130℃, the rubber is discharged to obtain the second stage final rubber.

[0043] After the two-stage final rubber compound is sheeted and left to stand, a rubber dam composite material is obtained.

[0044] The method provided by this invention is simple in process, has low equipment requirements, and has excellent processing performance, making it suitable for widespread use.

[0045] This invention involves mixing raw rubber, adding reinforcing fillers, binders, magnesium oxide, and plasticizers, and continuing mixing until the temperature reaches 110–150°C, at which point the rubber is discharged to obtain a first-stage masterbatch. Alternatively, raw rubber is added to an internal mixer and mixed for 25–35 seconds, followed by the addition of reinforcing fillers, binders, magnesium oxide, and plasticizers; the mixture is then further mixed at 40–80°C for 4–8 minutes.

[0046] The raw rubber described in this invention includes natural rubber, which is plasticized before use until the Mooney viscosity ML(1+4)100 value is 40-70. Preferably, the natural rubber is plasticized through a thin pass 2-20 times, with the roller temperature controlled at 50-70°C.

[0047] After obtaining the first stage of masterbatch, the present invention cools and allows it to stand, then mixes it with vulcanizing agent, accelerator, and activator for further intensive mixing. When the temperature reaches 90-130°C, the rubber is discharged to obtain the second stage of final compound. The first stage of masterbatch is cooled to a temperature below 80°C and allowed to stand for more than 30 minutes. In the present invention, the time for further intensive mixing with vulcanizing agent, accelerator, and activator is 1-3 minutes.

[0048] After obtaining the two-stage final compound, the present invention sheets the two-stage final compound and then allows it to stand to obtain the rubber dam composite material. In the present invention, the temperature for standing the two-stage final compound after sheeting is 20–30°C, and the time is 18–24 hours. The present invention then vulcanizes the compound, i.e., the rubber dam composite material, and performs relevant physical and mechanical property tests.

[0049] The rubber dam composite material prepared by the above-described process of this invention uses butyl rubber, which has good air tightness. When applied to rubber dams, it can significantly improve their gas retention performance. Utilizing its low unsaturation, the rubber dam composite material exhibits excellent aging resistance and UV resistance, fully meeting the environmental requirements for rubber dam use. This invention employs a combination of specific types of adhesives, significantly improving the gas retention performance of rubber dams without affecting interlayer bonding. This has significant economic implications for realizing the application of butyl rubber in rubber dams.

[0050] To further illustrate the present invention, the following detailed description, in conjunction with embodiments, of a rubber dam composite material with excellent airtightness and long service life and its preparation method, should not be construed as limiting the scope of protection of the present invention.

[0051] In the following examples, halogenated butyl rubber is a product of Shandong Jingbo Zhongju New Materials Co., Ltd., preferably brominated butyl rubber; natural rubber and EPDM rubber are commercially available brands; other raw and auxiliary materials are commercially available products.

[0052] Example 1

[0053] A rubber dam composite material with excellent airtightness and long service life, comprising the following components by weight: 60 parts brominated butyl rubber, 20 parts EPDM rubber, 20 parts natural rubber, 60 parts carbon black, 30 parts calcium carbonate, 1.0 part magnesium oxide, 10 parts zinc oxide, 15 parts paraffin oil, 2 parts Koresin, 1 part B-16S, 1.5 parts sulfur, 1 part accelerator DM, 1.5 parts accelerator CZ, 2 parts dicumyl peroxide (DCP), and 1 part triallyl isocyanurate (TAIC).

[0054] The preparation method of a rubber dam composite material with excellent airtightness and long service life is as follows:

[0055] 1) First, plasticize the natural rubber on a two-roll mill, let it stand for 8 hours, and then make plasticized rubber;

[0056] 2) Add brominated butyl rubber, EPDM rubber, and plasticized rubber in sequence, mix for 1 minute, then add carbon black, calcium carbonate, magnesium oxide, and adhesive in sequence, mix for 2 minutes, then add plasticizer and mix. When the temperature in the internal mixer reaches 130℃, discharge the rubber to obtain a first-stage masterbatch.

[0057] 3) After the first stage of masterbatch from step 2) has cooled and been left to stand for more than 2 hours, put the masterbatch, activator, vulcanizing agent, accelerator, etc. into the internal mixer and continue to mix. When the temperature in the internal mixer reaches 110°C, discharge the rubber to obtain the second stage final rubber.

[0058] 4) Pass it through a two-roll mill 6 times, with a 2mm roller gap, and let it stand for 18 hours at a temperature of 20-30℃ to obtain the compound rubber, which is the rubber dam composite material.

[0059] 5) The compound obtained in step 4) is tested for vulcanization characteristics using a rotorless vulcanizer. Vulcanized rubber samples are obtained using a flat vulcanizer and relevant physical and mechanical properties are tested.

[0060] The vulcanization temperature in step 5) is 160°C.

[0061] Example 2

[0062] A rubber dam composite material with excellent airtightness and long service life, comprising the following raw materials by weight: 60 parts brominated butyl rubber, 40 parts ethylene propylene diene monomer (EPDM) rubber, 60 parts carbon black, 30 parts calcium carbonate, 1 part magnesium oxide, 8 parts zinc oxide, 15 parts paraffin oil, 2 parts Koresin, 1 part B-16S, 1.5 parts sulfur, 1 part accelerator DM, 1.5 parts accelerator CZ, 2 parts dicumyl peroxide (DCP), and 1 part triallyl isocyanurate (TAIC).

[0063] The rubber dam composite material was prepared using the same preparation method as in Example 1.

[0064] Comparative Example 1

[0065] A rubber dam and air shield dam composite material with excellent airtightness and long service life, comprising the following raw materials by weight: 100 parts EPDM rubber, 60 parts carbon black, 30 parts calcium carbonate, 10 parts zinc oxide, 15 parts paraffin oil, 1.5 parts sulfur, 1 part accelerator NS, 1.5 parts accelerator CZ, 6 parts dicumyl peroxide (DCP), and 2 parts triallyl isocyanurate (TAIC).

[0066] The rubber dam composite material was prepared using the same preparation method as in Example 1.

[0067] Comparative Example 2

[0068] A rubber dam composite material with excellent airtightness and long service life, comprising the following raw materials by weight: 40 parts natural rubber, 60 parts EPDM rubber, 60 parts carbon black, 30 parts calcium carbonate, 6 parts zinc oxide, 15 parts paraffin oil, 1.5 parts sulfur, 1 part accelerator NS, 1.5 parts accelerator CZ, 6 parts dicumyl peroxide (DCP), and 2 parts triallyl isocyanurate (TAIC).

[0069] The rubber dam composite material was prepared using the same preparation method as in Example 1.

[0070] Comparative Example 3

[0071] A rubber dam composite material with excellent airtightness and long service life, comprising the following raw materials by weight: 60 parts brominated butyl rubber, 40 parts EPDM rubber, 60 parts carbon black, 30 parts calcium carbonate, 1 part magnesium oxide, 10 parts zinc oxide, 15 parts plasticizer, 1.2 parts resorcinol, 3 parts silica, 3 parts RA65, 1.5 parts sulfur, 1 part accelerator DM, 1.5 parts accelerator CZ, 2 parts dicumyl peroxide (DCP), and 1 part triallyl isocyanurate (TAIC).

[0072] The rubber dam composite material was prepared using the same preparation method as in Example 1.

[0073] The composite materials prepared in the examples and comparative examples of this invention were subjected to performance tests, and the results are shown in Table 1:

[0074] Table 1. Performance test results of rubber dam composite materials in the examples and comparative examples.

[0075]

[0076] As can be seen from Examples 1-2 and Comparative Examples 1-3, the rubber dam composite material prepared in the embodiments of the present invention exhibits a decreased permeability coefficient, excellent elongation at break, and a tensile strength greater than 12 MPa, exceeding industry standards and meeting usage requirements. This demonstrates that improving the gas retention performance of rubber dams using butyl rubber is feasible. Furthermore, the rubber dam composite material prepared using butyl rubber shows improved aging performance while maintaining unchanged ozone aging performance, contributing to extended service life of the rubber dam and achieving the goal of reducing carbon emissions. Comparing Examples 1-2 and Comparative Example 3, the selection of specific super-tackifying resin Koresin and modified resorcinol-formaldehyde resin B-16S as adhesives resulted in a significantly higher interlayer adhesion of the vulcanizate compared to the resorcinol-formaldehyde tackifying system, while also exceeding that of Comparative Examples 1-2. This indicates that the preferred tackifier of the present invention is effective. This invention partially replaces natural rubber and EPDM rubber in traditional formulations with butyl rubber, improving the processing performance of EPDM rubber, enhancing the gas retention performance of rubber dams, and helping to further improve the overall performance of rubber. The specially selected adhesive improves the adhesion problem of butyl rubber, providing beneficial technical support for the selection of raw materials for rubber dams, and has broad market prospects.

[0077] As can be seen from the above embodiments, the present invention provides a rubber dam composite material with excellent airtightness and long service life. The raw materials for preparation include the following components: 100 parts of raw rubber, 40-100 parts of reinforcing filler, 2-15 parts of activator, 4-30 parts of plasticizer, 0-10 parts of magnesium oxide, 1.0-10.0 parts of accelerator, 0.5-10 parts of vulcanizing agent, and 0.5-10.0 parts of binder. The raw rubber includes butyl rubber and a second rubber component in a mass ratio of (10-90):(10-90), wherein the second rubber component is EPDM rubber and / or natural rubber. The binder is selected from tackifying resins and modified phenolic resins. Under the combined action of the above-mentioned specific types and amounts of raw materials, the above-mentioned rubber dam composite material has excellent aging resistance and UV resistance, and excellent adhesion between different rubber layers (or with polyester or nylon impregnated canvas).

[0078] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A rubber dam composite material with excellent airtightness and long service life, the raw materials for which are prepared include the following components: 100 parts raw rubber, 40-100 parts reinforcing filler, 2-15 parts activator, 4-30 parts plasticizer, 0-10 parts magnesium oxide, 1.0-10.0 parts accelerator, 0.5-10 parts vulcanizing agent and 0.5-10.0 parts adhesive; The raw rubber is composed of brominated butyl rubber and a second rubber component in a mass ratio of (10~90):(10~90), wherein the second rubber component is EPDM rubber and / or natural rubber. The adhesive is selected from tackifying resin and modified phenolic resin; the tackifying resin is super tackifying resin Koresin; the modified phenolic resin is modified resorcinol formaldehyde resin B-16S; the mass ratio of the tackifying resin to the modified phenolic resin is 0.5~10:0.5~8; The rubber dam composite material is used in rubber dams.

2. The rubber dam composite material with excellent airtightness and long service life according to claim 1, characterized in that, The reinforcing filler is selected from one or more of carbon black, calcium carbonate, calcium sulfate, dolomite powder, montmorillonite, clay, barium sulfate, talc, magnesium carbonate, silica, magnesium silicate, graphene, and cellulose bio-based materials.

3. The rubber dam composite material with excellent airtightness and long service life according to claim 1, characterized in that, The activator is selected from one or more of zinc oxide, stearic acid, lead oxide, and titanium dioxide; The plasticizer is selected from one or more of naphthenic oils, aromatic oils, paraffin oils, butyl oleate, and dibutyl phthalate.

4. The rubber dam composite material with excellent airtightness and long service life according to claim 1, characterized in that, The accelerator is selected from one or more of the following: thiazole accelerators, thiuram accelerators, dithiocarbamate accelerators, xanthate accelerators, guanidine accelerators, aldehyde amine accelerators, sulfenamide accelerators, and thiourea accelerators. The vulcanizing agent is selected from sulfur and / or peroxides.

5. A method for preparing the rubber dam composite material with excellent airtightness and long service life as described in claim 1, comprising the following steps: The raw rubber is mixed, and reinforcing fillers, binders, magnesium oxide and plasticizers are added and mixed again. When the temperature reaches 110~150℃, the rubber is discharged to obtain a first-stage masterbatch. The binder is selected from tackifying resins and modified phenolic resins. After cooling the first stage of masterbatch, it is left to stand, then mixed with vulcanizing agent, accelerator and activator and continued to be mixed. When the temperature reaches 90~130℃, the rubber is discharged to obtain the second stage final rubber. After the two-stage final rubber compound is sheeted out, it is left to stand and vulcanize to obtain the rubber dam composite material.

6. The preparation method according to claim 5, characterized in that, The raw rubber includes natural rubber, which is masticated before use until the Mooney viscosity ML(1+4) at 100°C is 40~70.

7. The preparation method according to claim 5, characterized in that, Add reinforcing filler, binder, magnesium oxide and plasticizer and continue mixing at 40~80℃ for 4~8 minutes; The temperature of the first stage of masterbatch cooling is below 80°C, and the standing time is greater than 30 minutes. The mixture is then further mixed with the vulcanizing agent, accelerator, and activator and kneaded for another 1-3 minutes. The temperature at which the two-stage final rubber is left to stand after being sheeted is 20~30℃ for 18~24 hours.

8. The preparation method according to claim 5, characterized in that, The vulcanization temperature is 130~180℃, the vulcanization pressure is 20~40 tons, and the time is 5~60 minutes.

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