Dense non-precipitation mixing type water-swelling rubber material and preparation method thereof

Abstract

The invention relates to the technical field of rubber, in particular to a dense non-precipitation mixing type water-swelling rubber material and a preparation method thereof. The water-swellable rubber material is prepared from the following raw materials in parts by weight: 50 to 70 parts of ethylene propylene diene monomer, 40 to 50 parts of chloroprene rubber, 50 to 80 parts of water-swellable resin, 1.5 to 2.5 parts of carnauba wax, 1 to 3 parts of sulfur, 10 to 35 parts of spray carbon black, 3 to 5 parts of anti-aging additive, 15 to 45 parts of filler, 10 to 15 parts of softening agent and 1 to 2 parts of accelerant. The prepared rubber material has a good water swelling effect, the plugging effect and the plugging strength of the rubber material are effectively guaranteed, meanwhile, the rubber material is free of precipitates when soaked in water, and the service life of the rubber material is relatively long; furthermore, the anti-aging performance is good, and the service life is prolonged to a certain extent.

Description

Technical Field

[0001] The invention relates to the technical field of rubber, and in particular to a water-swellable rubber material for mixing without precipitation and a preparation method thereof. Background Art

[0002] Water-swelling waterproof rubber is a new type of waterproof material with a unique waterproof mechanism: on the one hand, it has the elasticity and extensibility of rubber waterproof products and plays an elastic sealing role; on the other hand, it has the function of swelling when exposed to water and stopping water with water, and is a functional polymer material with dual water-stopping effects. Internationally, the development of water-swelling waterproof materials largely relies on the development of swelling agents, i.e., swelling by water absorption. Due to the expansion of applications, water-swelling materials have been partially applied in technological innovation from the traditional engineering sealing application field to some high-end electronic products for outdoor structural sealing scenarios. However, the current commercially available powdered super absorbent resin is used as the swelling agent, and its sealing effect and sealing strength are relatively poor, which is not very ideal. Furthermore, rubber materials will age to varying degrees when used for a long time, which not only shortens its service life to a certain extent, but also affects its sealing effect. Therefore, the present invention provides a water-swelling rubber material for non-precipitation mixing and a preparation method thereof, which are used to solve the above-mentioned technical problems. Summary of the invention

[0003] The object of the present invention is to provide a water-swellable rubber material for a non-precipitation mixing type and a preparation method thereof, wherein the prepared rubber material has a good water absorption and swelling effect, effectively guarantees its sealing effect and sealing strength, and at the same time, has no precipitation when soaked in water, and has a relatively long service life. Furthermore, it also has a good anti-aging performance, which prolongs its service life to a certain extent.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A water-swellable rubber material for a non-separating mixing type is composed of the following raw materials in parts by weight: 50-70 parts of EPDM rubber, 40-50 parts of chloroprene rubber, 50-80 parts of water-swellable resin, 1.5-2.5 parts of carnauba wax, 1-3 parts of sulfur, 10-35 parts of spray carbon black, 3-5 parts of anti-aging additives, 15-45 parts of fillers, 10-15 parts of softeners and 1-2 parts of accelerators.

[0006] Furthermore, the preparation method of the water-swellable resin comprises the following steps:

[0007] Step 1, to a 5-8wt% bentonite aqueous phase dispersion, 15-25% acrylamide, 8-12% acrylic acid, and 6-10% 2-acrylamide-2-methylpropanesulfonic acid are added respectively, and after mixing and stirring evenly, the temperature is adjusted to 2-4°C, and under nitrogen protection, a cross-linking agent of 30-50% acrylic acid and 10-20% ammonium persulfate are added respectively, and after uniform dispersion, the mixture is kept warm at 50-60°C for 3-6h; after the reaction is completed, the reaction product is taken out, dried, crushed and passed through a 10-20 mesh sieve, and the obtained solid material is stored and used for standby;

[0008] Step 2: Mix octadecanoic acid and chloroform in a mass ratio of 1:1 to 3, heat and stir to completely dissolve the octadecanoic acid, then add a solid material 2 to 3 times the mass of the octadecanoic acid, mix well and react for 4 to 7 hours; after the reaction is completed, transfer the resulting components into a drying device to evaporate the solvent therein, and the final product is a water-absorbing and swelling resin.

[0009] Furthermore, the cross-linking agent is compounded by diallyl ammonium chloride and N,N-methylenebisacrylamide in a mass ratio of 2 to 3:1.

[0010] Furthermore, the preparation method of the anti-aging aid comprises the following steps:

[0011] The first step is to add bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform at a dosage ratio of 0.05-0.1 g / mL, add 0.2-0.3 times the mass of glycidyl methacrylate and 0.15-0.25 times the mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate while stirring, mix and stir evenly, and then keep warm at 50-70° C. for 3-6 hours; after the reaction is completed, filter out the ion exchange resin in the product component and evaporate the chloroform in the remaining filtrate, and the obtained product is recorded as a modifier;

[0012] The second step is to uniformly disperse the pretreated nano-microspheres in a mixed solvent prepared by mixing DMF and toluene in a volume ratio of 5 to 8:1 at a solid-liquid ratio of 10 to 30 g / L, and then add 2,4-dihydroxybenzophenone in an amount of 0.3 to 0.4 times the mass of the pretreated nano-microspheres, and after mixing and stirring evenly, add a modifier in an amount of 2 to 3 times the mass of the pretreated nano-microspheres under nitrogen protection, and after heating the obtained mixed solution to 75 to 85° C., add benzoyl peroxide in an amount of 2 to 3.5% of the mass of the modifier, and react by stirring and keeping warm for 20 to 30 hours; after the reaction is completed, filter the obtained reaction product, wash the obtained filter cake with ether, and then vacuum dry it, and the final product is an anti-aging auxiliary agent.

[0013] Furthermore, the preparation method of the pretreated nano-microspheres is: 3-aminopropyltrimethoxysilane is added into an ethanol aqueous solution with a volume concentration of 60-80% at a dosage ratio of 5-10 g / L, and then nano-microspheres with a mass of 1-1.5 times that of 3-aminopropyltrimethoxysilane are added, mixed and stirred for 40-60 minutes, and then centrifuged, washed and dried in sequence to obtain the pretreated nano-microspheres.

[0014] Furthermore, the preparation method of the nano-microspheres is as follows: zinc acetate is added into DMF at a dosage ratio of 0.05 to 0.08 mol / L, and after ultrasonic dispersion for 20 to 30 minutes, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid with a molar amount of 0.8 to 1.2 times that of zinc acetate is added, and after mixing and stirring evenly, the obtained mixed components are kept warm for reaction at a temperature of 140 to 160° C. for 10 to 20 hours; after the reaction is completed, the obtained product components are centrifuged, washed and dried in sequence to obtain nano-microspheres.

[0015] Furthermore, the filler is formed by mixing clay and active magnesium oxide in a mass ratio of 2 to 5:1, and the active magnesium oxide has an iodine absorption value of 120 to 180 ml / g and a specific surface area of ​​120 to 160 m 2 / g.

[0016] Furthermore, the softener is selected from any one of stearic acid, cyclohexane oil, and dibutyl phthalate.

[0017] Furthermore, the accelerator is selected from any one of accelerator CZ, accelerator NS and accelerator DM.

[0018] A method for preparing a water-swellable rubber material that is non-separable and kneadable, comprising the following steps:

[0019] S1. Accurately weigh all raw materials according to the formula requirements, set the temperature of the internal mixer to 120-125°C, and then put the EPDM rubber and chloroprene rubber into the internal mixer for internal mixing and kneading for 50-70s; after kneading, add the remaining raw materials except the water-swellable resin, sulfur and accelerator into the internal mixer, stir and knead into a mass, and then store the obtained mixed slurry for standby use;

[0020] S2, raising the temperature of the mixed slurry to 100-105°C, then adding the water-absorbing swelling resin, mixing it to 120-125°C and transferring it to an open mill for refining for 3-6 minutes; after the refining is completed, the sheet is cooled to room temperature, and the obtained mixed rubber is stored and used for standby;

[0021] S3. The mixed rubber obtained in S2 is put into an internal mixer and kneaded for 50 to 100 seconds. After kneading, the remaining raw materials are added, and the mixture is kneaded to 100 to 105°C, and then transferred to an open mixer for tumbling for 5 to 8 minutes. Finally, the sheet is calendered to obtain a finished product of a water-swellable rubber material for sealing without precipitation.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention uses zinc acetate and 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid as raw materials to prepare nano-microspheres with a spherical porous structure, and then uses 3-aminopropyltrimethoxysilane to modify the nano-microspheres to obtain pre-treated nano-microspheres. In addition, the present invention uses bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, glycidyl methacrylate, etc. as raw materials to prepare a modifier. Then the pre-treated nano-microspheres are dispersed in a mixed solvent and 2,4-dihydroxybenzophenone is added, and the mixing and stirring are performed so that the 2,4-dihydroxybenzophenone is uniformly dispersed and adsorbed on the surface and internal pore structure of the pre-treated nano-microspheres, and the modifier reacts with the active groups on the pre-treated nano-microspheres through chemical bonds under the action of benzoyl peroxide, and finally "grafted" into the pore structure on the surface and inside thereof, and a dense anti-aging film layer is formed on the surface and inside thereof, and finally an anti-aging auxiliary agent is prepared. The prepared anti-aging agent significantly improves its anti-aging performance under the synergistic cooperation of nano-microspheres, 2,4-dihydroxybenzophenone and modifier. At the same time, the use of the anti-aging agent also significantly improves the anti-aging performance of the water-swellable rubber material, effectively extending its service life.

[0024] 2. The present invention uses bentonite, acrylamide, acrylic acid, 2-acrylamido-2-methylpropanesulfonic acid, a cross-linking agent, etc. as raw materials, reacts them under the action of ammonium persulfate, and then obtains a solid material after drying and crushing. The obtained solid material is put into a mixture formed by octadecanoic acid and chloroform, and a chemical reaction occurs after mixing evenly. Finally, octadecanoic acid is successfully coated on the surface of the solid material to obtain a water-swelling resin. The obtained water-swelling resin not only has good water absorption, but also expands after absorbing water, which can play a good plugging effect. It also has good mechanical properties, enhances the plugging strength, and improves the pressure-bearing capacity of the plugging layer. In addition, the water-swelling resin prepared by the present invention can effectively improve the compatibility between the composite materials, prevent the possibility of precipitation, and has no precipitate when it is soaked in water, and has a relatively long service life. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Example 1

[0027] A water-swellable rubber material for a non-precipitation mixing type is composed of the following raw materials in parts by weight: 50 parts of EPDM rubber, 40 parts of chloroprene rubber, 50 parts of water-swellable resin, 1.5 parts of carnauba wax, 1 part of sulfur, 10 parts of spray carbon black, 3 parts of anti-aging additives, 15 parts of fillers, 10 parts of stearic acid and 1 part of accelerator CZ; wherein the filler is a mixture of clay and active magnesium oxide in a mass ratio of 2:1, and the iodine absorption value of the active magnesium oxide is 120 ml / g and the specific surface area is 120 m 2 / g.

[0028] The preparation method of the water-swellable resin comprises the following steps:

[0029] Step 1, add 15% of acrylamide, 8% of acrylic acid, and 6% of 2-acrylamido-2-methylpropanesulfonic acid to a 5wt% bentonite aqueous phase dispersion, mix and stir evenly, adjust the temperature to 2°C, and add 30% of a cross-linking agent and 10% of ammonium persulfate under nitrogen protection, disperse evenly, and keep warm at 50°C for 3h; after the reaction is completed, take out the reaction product, dry, crush and pass through a 10-mesh sieve, and store the obtained solid material for standby use; wherein the cross-linking agent is prepared by compounding diallyl ammonium chloride and N,N-methylenebisacrylamide in a mass ratio of 2:1;

[0030] Step 2: Mix octadecanoic acid and chloroform in a mass ratio of 1:1, heat and stir to completely dissolve the octadecanoic acid, then add a solid material twice the mass of the octadecanoic acid, mix well and react for 4 hours; after the reaction is completed, transfer the resulting components into a drying device to evaporate the solvent therein, and the final product is a water-swellable resin.

[0031] The preparation method of the anti-aging auxiliary agent comprises the following steps:

[0032] The first step is to add bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform at a dosage ratio of 0.05 g / mL, add 0.2 times the mass of glycidyl methacrylate and 0.15 times the mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform while stirring, mix and stir evenly, and then keep warm at 50°C for 3 hours; after the reaction is completed, filter out the ion exchange resin in the product component and evaporate the chloroform in the remaining filtrate, and the resultant is recorded as a modifier;

[0033] The second step is to uniformly disperse the pretreated nano-microspheres in a mixed solvent prepared by mixing DMF and toluene in a volume ratio of 5:1 at a solid-liquid ratio of 10 g / L, and then add 2,4-dihydroxybenzophenone in an amount of 0.3 times the mass of the pretreated nano-microspheres, mix and stir evenly, and then add a modifier in an amount of 2 times the mass of the pretreated nano-microspheres under nitrogen protection, and then heat the obtained mixed solution to 75° C. and add benzoyl peroxide in an amount of 2% of the mass of the modifier, and stir and react for 20 hours under heat preservation and stirring; after the reaction is completed, filter the obtained reaction product, wash the obtained filter cake with ether and then vacuum dry it, and the final product is an anti-aging additive.

[0034] The preparation method of the pretreated nano-microspheres is as follows: 3-aminopropyltrimethoxysilane is added into an ethanol aqueous solution with a volume concentration of 60% at a dosage ratio of 5 g / L, and then nano-microspheres of equal mass to 3-aminopropyltrimethoxysilane are added, mixed and stirred for 40 minutes, and then centrifuged and washed and dried in sequence to obtain the pretreated nano-microspheres.

[0035] The preparation method of nano-microspheres is as follows: zinc acetate is added into DMF at a dosage ratio of 0.05 mol / L, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid whose molar amount is 0.8 times of zinc acetate is added after ultrasonic dispersion for 20 minutes, and the mixed components are mixed and stirred evenly, and the obtained mixed components are kept at a temperature of 140° C. for reaction for 10 hours; after the reaction is completed, the obtained product components are centrifuged, washed and dried in sequence to obtain nano-microspheres.

[0036] A method for preparing a water-swellable rubber material that is non-separable and kneadable, comprising the following steps:

[0037] S1. Accurately weigh all raw materials according to the formula requirements, set the temperature of the internal mixer to 120°C, and then put the EPDM rubber and chloroprene rubber into the internal mixer for internal mixing and kneading for 50 seconds; after kneading, add the remaining raw materials except the water-swellable resin, sulfur and accelerator into the internal mixer, stir and knead into a mass, and then store the obtained mixed slurry for standby use;

[0038] S2, raising the temperature of the mixed slurry to 100°C, then adding the water-absorbing swelling resin, mixing it to 120°C and transferring it to an open mill for refining for 3 minutes; after the refining is completed, the sheet is cooled to room temperature, and the obtained mixed rubber is stored and used for standby;

[0039] S3. The rubber mixture obtained in S2 is put into an internal mixer and kneaded for 50 seconds. After kneading, the remaining raw materials are added, and the mixture is kneaded to 100°C and then transferred to an open mixer for tumbling for 5 minutes. Finally, the sheet is calendered to obtain a finished product of a water-swellable rubber material for sealing without precipitation.

[0040] Example 2

[0041] The preparation method of a water-swellable rubber material for a non-precipitation mixing type provided in this embodiment is basically the same as that in Example 1, except that the specific composition of the raw materials used and the preparation method of the anti-aging additive are not completely the same, and the specific composition of the raw materials used in this embodiment and the preparation method of the anti-aging additive are as follows:

[0042] A water-swellable rubber material for a non-separating mixing type is composed of the following raw materials in parts by weight: 60 parts of EPDM rubber, 45 parts of chloroprene rubber, 60 parts of water-swellable resin, 2.0 parts of carnauba wax, 2 parts of sulfur, 20 parts of spray carbon black, 4 parts of anti-aging additives, 30 parts of fillers, 10 parts of cyclohexane oil and 1.5 parts of accelerator NS; wherein the filler is prepared by mixing clay and active magnesium oxide in a mass ratio of 3:1, and the iodine absorption value of the active magnesium oxide is 150 ml / g and the specific surface area is 140 m2 / g.

[0043] The preparation method of the water-swellable resin comprises the following steps:

[0044] Step 1, add 20% acrylamide, 10% acrylic acid, and 8% 2-acrylamido-2-methylpropanesulfonic acid to a 6wt% bentonite aqueous phase dispersion, mix and stir evenly, adjust the temperature to 3°C, and add a cross-linking agent of 40% acrylic acid and 15% ammonium persulfate under nitrogen protection, and keep the mixture at 55°C for 4h after uniform dispersion; after the reaction is completed, take out the reaction product, dry it, crush it and pass it through a 20-mesh sieve, and store the obtained solid material for standby use; wherein the cross-linking agent is compounded by diallyl ammonium chloride and N,N-methylenebisacrylamide in a mass ratio of 2.5:1;

[0045] Step 2: Mix octadecanoic acid and chloroform in a mass ratio of 1:2, heat and stir to completely dissolve the octadecanoic acid, then add a solid material twice the mass of the octadecanoic acid, mix well and react for 5 hours; after the reaction is completed, transfer the resulting components into a drying device to evaporate the solvent therein, and the final result is a water-swellable resin.

[0046] The preparation method of the anti-aging auxiliary agent comprises the following steps:

[0047] The first step is to add bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform at a dosage ratio of 0.08 g / mL, add 0.25 times the mass of glycidyl methacrylate and 0.2 times the mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform while stirring, mix and stir evenly, and then keep warm at 60°C for 5 hours; after the reaction is completed, filter out the ion exchange resin in the product component and evaporate the chloroform in the remaining filtrate, and the obtained product is recorded as a modifier;

[0048] The second step is to uniformly disperse the pretreated nano-microspheres in a mixed solvent prepared by mixing DMF and toluene in a volume ratio of 6:1 at a solid-liquid ratio of 20 g / L, and then add 2,4-dihydroxybenzophenone in an amount of 0.35 times the mass of the pretreated nano-microspheres, mix and stir evenly, and then add a modifier in an amount of 2 times the mass of the pretreated nano-microspheres under nitrogen protection, and then heat the obtained mixed solution to 80° C. and add benzoyl peroxide in an amount of 3.0% of the mass of the modifier, and stir and react for 25 hours under heat preservation and stirring; after the reaction is completed, filter the obtained reaction product, wash the obtained filter cake with ether and then vacuum dry it, and the final product is an anti-aging additive.

[0049] The preparation method of the pretreated nano-microspheres is as follows: 3-aminopropyltrimethoxysilane is added into an ethanol aqueous solution with a volume concentration of 70% at a dosage ratio of 8 g / L, and then nano-microspheres with a mass 1.5 times that of 3-aminopropyltrimethoxysilane are added, mixed and stirred for 50 minutes, and then centrifuged and washed and dried in sequence to obtain the pretreated nano-microspheres.

[0050] The preparation method of nano-microspheres is as follows: zinc acetate is added into DMF at a dosage ratio of 0.06 mol / L, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid in an equal molar amount to zinc acetate is added after ultrasonic dispersion for 25 minutes, the mixture is mixed and stirred evenly, and the obtained mixed components are kept at a temperature of 150° C. for reaction for 15 hours; after the reaction is completed, the obtained product components are centrifuged, washed and dried in sequence to obtain nano-microspheres.

[0051] Example 3

[0052] The preparation method of a water-swellable rubber material for a non-precipitation mixing type provided in this embodiment is basically the same as that in Example 1, except that the specific composition of the raw materials used and the preparation method of the anti-aging additive are not completely the same, and the specific composition of the raw materials used in this embodiment and the preparation method of the anti-aging additive are as follows:

[0053] A water-swellable rubber material for a non-separating mixing type is composed of the following raw materials in parts by weight: 70 parts of EPDM rubber, 50 parts of chloroprene rubber, 80 parts of water-swellable resin, 2.5 parts of carnauba wax, 3 parts of sulfur, 35 parts of spray carbon black, 5 parts of anti-aging additives, 45 parts of fillers, 15 parts of dibutyl phthalate and 2 parts of accelerator DM; wherein the filler is prepared by mixing clay and active magnesium oxide in a mass ratio of 5:1, and the iodine absorption value of the active magnesium oxide is 180 ml / g and the specific surface area is 160 m2 / g.

[0054] The preparation method of the water-swellable resin comprises the following steps:

[0055] Step 1, add 25% acrylamide, 12% acrylic acid, and 10% 2-acrylamido-2-methylpropanesulfonic acid to 8wt% bentonite aqueous phase dispersion, mix and stir evenly, adjust the temperature to 4°C, and add 50% of acrylic acid and 20% ammonium persulfate as a cross-linking agent under nitrogen protection, disperse evenly, and keep warm at 60°C for 6h; after the reaction is completed, take out the reaction product, dry, crush and pass through a 20-mesh sieve, and store the obtained solid material for standby use; wherein the cross-linking agent is prepared by compounding diallyl ammonium chloride and N,N-methylenebisacrylamide in a mass ratio of 3:1;

[0056] Step 2: Mix octadecanoic acid and chloroform in a mass ratio of 1:3, heat and stir to completely dissolve the octadecanoic acid, then add a solid material 3 times the mass of the octadecanoic acid, mix well and react for 7 hours; after the reaction is completed, transfer the resulting components into a drying device to evaporate the solvent therein, and the final result is a water-swellable resin.

[0057] The preparation method of the anti-aging auxiliary agent comprises the following steps:

[0058] The first step is to add bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform at a dosage ratio of 0.1 g / mL, add 0.3 times the mass of glycidyl methacrylate and 0.25 times the mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform while stirring, mix and stir evenly, and then keep warm at 70°C for 6 hours; after the reaction is completed, filter out the ion exchange resin in the product component and evaporate the chloroform in the remaining filtrate, and the obtained product is recorded as a modifier;

[0059] The second step is to uniformly disperse the pretreated nano-microspheres in a mixed solvent prepared by mixing DMF and toluene in a volume ratio of 8:1 at a solid-liquid ratio of 30 g / L, and then add 2,4-dihydroxybenzophenone in an amount of 0.4 times the mass of the pretreated nano-microspheres, mix and stir evenly, and then add a modifier in an amount of 3 times the mass of the pretreated nano-microspheres under nitrogen protection, and then heat the obtained mixed solution to 85° C. and add benzoyl peroxide in an amount of 3.5% of the mass of the modifier, and stir and react for 30 hours under heat preservation and stirring; after the reaction is completed, filter the obtained reaction product, wash the obtained filter cake with ether and then vacuum dry it, and the final product is an anti-aging additive.

[0060] The preparation method of the pretreated nano-microspheres is as follows: 3-aminopropyltrimethoxysilane is added into an ethanol aqueous solution with a volume concentration of 80% at a dosage ratio of 10 g / L, and then nano-microspheres with a mass 1.5 times that of 3-aminopropyltrimethoxysilane are added, mixed and stirred for 60 minutes, and then centrifuged and washed and dried in sequence to obtain the pretreated nano-microspheres.

[0061] The preparation method of nano-microspheres is as follows: zinc acetate is added into DMF at a dosage ratio of 0.08 mol / L, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid whose molar amount is 1.2 times of zinc acetate is added after ultrasonic dispersion for 30 minutes, and the mixed components are mixed and stirred evenly, and the obtained mixed components are kept at a temperature of 160° C. for reaction for 20 hours; after the reaction is completed, the obtained product components are centrifuged, washed and dried in sequence to obtain nano-microspheres.

[0062] Comparative Example 1: The main difference between this example and Example 1 is that an equal amount of nano-microspheres are used to replace the anti-aging additive in this example.

[0063] Comparative Example 2: The main difference between this example and Example 1 is that in this example, 2,4-dihydroxybenzophenone is not used in the process of preparing the anti-aging additive.

[0064] Comparative Example 3: The main difference between this example and Example 1 is that an equal amount of sodium polyacrylate resin is used in this example to replace the water-swellable resin.

[0065] Performance Testing

[0066] The rubber sheet samples (size 20×20×2 mm) prepared in Examples 1 to 3 and Comparative Examples 1 to 3 were subjected to the following performance tests in the test solution:

[0067] 1. Expansion test: each group of rubber sheet samples were subjected to an expansion test using a test solution; wherein the test solution consisted of the following weight parts: 708 parts of distilled water, 485.4 parts of NaOH solution (pH=12), 452.9 parts of HCl solution (pH=5), and 380.6 parts of NaCl solution (5wt%);

[0068] The expansion rate is calculated as follows:

[0069]

[0070] During the experiment, the tensile properties of each group of rubber samples were measured according to the national standard GB / T528-2009, and the Shore hardness of each group of rubber samples was measured according to the national standard GB / T531.2-2009.

[0071] 2. Anti-aging performance test: According to "GB / T16585-1996 Test method for artificial weathering of vulcanized rubber (fluorescent ultraviolet lamp)", the change rate of tensile strength and elongation at break of each group of rubber sheet samples after ultraviolet aging treatment were measured.

[0072] The relevant data obtained after the above experimental test are recorded in the following table:

[0073]

[0074] By comparing and analyzing the relevant data in the table, it can be seen that the rubber material prepared by the present invention has a good water absorption and swelling effect, effectively ensuring its blocking effect and blocking strength, and at the same time, it has no precipitate when soaked in water, and has a relatively long service life. Moreover, it also has a good anti-aging performance, which prolongs its service life to a certain extent. This shows that the water-swellable rubber material for non-precipitation mixing provided by the present invention and the preparation method thereof have a broader market prospect and are more suitable for promotion.

[0075] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0076] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A water-swellable rubber material for mixing without separation, characterized in that: The invention is composed of the following raw materials in parts by weight: 50-70 parts of EPDM rubber, 40-50 parts of chloroprene rubber, 50-80 parts of water-swelling resin, 1.5-2.5 parts of carnauba wax, 1-3 parts of sulfur, 10-35 parts of spray carbon black, 3-5 parts of anti-aging additive, 15-45 parts of filler, 10-15 parts of softener and 1-2 parts of accelerator.

2. The water-swellable rubber material for mixing without separation according to claim 1, characterized in that: The preparation method of the water-swellable resin comprises the following steps: Step 1, to a 5-8wt% bentonite aqueous phase dispersion, 15-25% acrylamide, 8-12% acrylic acid, and 6-10% 2-acrylamide-2-methylpropanesulfonic acid are added respectively, and after mixing and stirring evenly, the temperature is adjusted to 2-4°C, and under nitrogen protection, a cross-linking agent of 30-50% acrylic acid and 10-20% ammonium persulfate are added respectively, and after uniform dispersion, the mixture is kept warm at a temperature of 50-60°C for 3-6h; after the reaction is completed, the reaction product is taken out, dried, crushed and passed through a 10-20 mesh sieve, and the obtained solid material is stored and used for standby; Step 2: Mix octadecanoic acid and chloroform in a mass ratio of 1:1 to 3, heat and stir to completely dissolve the octadecanoic acid, then add a solid material 2 to 3 times the mass of the octadecanoic acid, mix well and react for 4 to 7 hours; after the reaction is completed, transfer the resulting components into a drying device to evaporate the solvent therein, and the final product is a water-absorbing and swelling resin.

3. The water-swellable rubber material for mixing without separation according to claim 2, characterized in that: The cross-linking agent is prepared by compounding diallyl ammonium chloride and N,N-methylenebisacrylamide in a mass ratio of 2 to 3:

1.

4. The water-swellable rubber material for mixing without separation according to claim 1, characterized in that: The preparation method of the anti-aging aid comprises the following steps: The first step is to add bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate into chloroform at a dosage ratio of 0.05-0.1 g / mL, add 0.2-0.3 times the mass of glycidyl methacrylate and 0.15-0.25 times the mass of bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate while stirring, mix and stir evenly, and then keep warm at 50-70° C. for 3-6 hours; after the reaction is completed, filter out the ion exchange resin in the product component and evaporate the chloroform in the remaining filtrate, and the obtained product is recorded as a modifier; The second step is to uniformly disperse the pretreated nano-microspheres in a mixed solvent prepared by mixing DMF and toluene in a volume ratio of 5 to 8:1 at a solid-liquid ratio of 10 to 30 g / L, and then add 2,4-dihydroxybenzophenone in an amount of 0.3 to 0.4 times the mass of the pretreated nano-microspheres, and after mixing and stirring evenly, add a modifier in an amount of 2 to 3 times the mass of the pretreated nano-microspheres under nitrogen protection, and after heating the obtained mixed solution to 75 to 85° C., add benzoyl peroxide in an amount of 2 to 3.5% of the mass of the modifier, and react by stirring and keeping warm for 20 to 30 hours; after the reaction is completed, filter the obtained reaction product, wash the obtained filter cake with ether, and then vacuum dry it, and the final product is an anti-aging auxiliary agent.

5. The water-swellable rubber material for mixing without separation according to claim 4, characterized in that: The preparation method of the pretreated nano-microspheres is as follows: 3-aminopropyltrimethoxysilane is added into an ethanol aqueous solution with a volume concentration of 60-80% at a dosage ratio of 5-10 g / L, and then nano-microspheres with a mass of 1-1.5 times that of 3-aminopropyltrimethoxysilane are added, mixed and stirred for 40-60 minutes, and then centrifuged and washed and dried in sequence to obtain the pretreated nano-microspheres.

6. The water-swellable rubber material for mixing without separation according to claim 5, characterized in that: The preparation method of the nano-microspheres is as follows: zinc acetate is added into DMF at a dosage ratio of 0.05-0.08 mol / L, and after ultrasonic dispersion for 20-30 minutes, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid with a molar amount of 0.8-1.2 times that of zinc acetate is added, and after mixing and stirring evenly, the obtained mixed components are kept at a temperature of 140-160° C. for reaction for 10-20 hours; After the reaction is completed, the resulting components are centrifuged, washed and dried in sequence to obtain nano-microspheres.

7. The water-swellable rubber material for mixing without separation according to claim 1, characterized in that: The filler is prepared by mixing clay and active magnesium oxide in a mass ratio of 2 to 5:1, and the active magnesium oxide has an iodine absorption value of 120 to 180 ml / g and a specific surface area of ​​120 to 160 m 2 / g.

8. The water-swellable rubber material for mixing without separation according to claim 1, characterized in that: The softener is selected from any one of stearic acid, cycloalkane oil and dibutyl phthalate.

9. The water-swellable rubber material for mixing without separation according to claim 1, characterized in that: The accelerator is selected from any one of accelerator CZ, accelerator NS and accelerator DM.

10. A method for preparing a water-swellable rubber material for mixing without precipitation according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. Accurately weigh all raw materials according to the formula requirements, set the temperature of the internal mixer to 120-125°C, and then put the EPDM rubber and chloroprene rubber into the internal mixer for internal mixing and kneading for 50-70s; after kneading, add the remaining raw materials except the water-swellable resin, sulfur and accelerator into the internal mixer, stir and knead into a mass, and then store the obtained mixed slurry for standby use; S2, raising the temperature of the mixed slurry to 100-105°C, then adding the water-absorbing swelling resin, mixing it to 120-125°C and transferring it to an open mill for refining for 3-6 minutes; after the refining is completed, the sheet is cooled to room temperature, and the obtained mixed rubber is stored and used for standby; S3. The mixed rubber obtained in S2 is put into an internal mixer and kneaded for 50 to 100 seconds. After kneading, the remaining raw materials are added, and the mixture is kneaded to 100 to 105°C, and then transferred to an open mixer for tumbling for 5 to 8 minutes. Finally, the sheet is calendered to obtain a finished product of a water-swellable rubber material for sealing without precipitation.

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