CN109762322B - Water-soluble rubber material and preparation method thereof - Google Patents
Water-soluble rubber material and preparation method thereof Download PDFInfo
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- CN109762322B CN109762322B CN201811638963.9A CN201811638963A CN109762322B CN 109762322 B CN109762322 B CN 109762322B CN 201811638963 A CN201811638963 A CN 201811638963A CN 109762322 B CN109762322 B CN 109762322B
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Abstract
The invention provides a water-soluble rubber and a preparation method thereof, wherein the water-soluble rubber is mainly prepared from the following components in parts by weight: 10-70 parts of dimethylolpropionic acid modified polyurethane (DMPA-PU), 15-30 parts of ethylenediamine propanesulfonic acid modified chitosan (EPS-CS), 5-30 parts of carboxymethyl modified nano silicon dioxide, 5-40 parts of compatilizer, 0.3-2 parts of coupling agent, 0.1-1 part of antioxidant, 1-5 parts of softener, 0.3-3 parts of cross-linking agent, 0.3-3 parts of accelerator and 0.5-6 parts of sulfur. The water-soluble rubber has certain rubber elasticity and strength due to the adoption of the graft modified macromolecular elastomer chain segment, has excellent water-soluble performance and mechanical performance due to the matching of natural water-soluble materials and other components, can be applied to the preparation of customized products in the military industry field and the petroleum field, and has higher economic value and social value.
Description
Technical Field
The invention relates to the field of functional polymer materials, in particular to a water-soluble rubber material and a preparation method thereof.
Background
At present, the water-swelling rubber is developed and matured day by day, and the defects of poor sealing caused by permanent deformation and creep of waterproof and leakage-stopping rubber sealing materials in the underground, water, buildings and the like and solidification shrinkage of scarf materials are overcome. However, in the fields of petrochemical industry, military industry, highways and the like, the materials are often required to be soluble or disappear after functioning, namely the demand for soluble rubber materials is increasingly strong.
Soluble rubber materials are mainly used for tool seals and soluble tools. At present, the dissoluble high polymer rubber materials rarely appear in the market, and although foreign companies occasionally appear products, the products have limitations and are difficult to consider both strength and dissolubility. And the difficulty of developing water-soluble rubber products which are free from environmental pollution after dissolution is higher. With the development of the oil and gas well reservoir transformation technology, the downhole tool applied to the oil and gas well reservoir transformation technology develops from drillable to soluble direction, and the soluble materials of the current downhole tool for oil and gas well reservoir transformation comprise the following materials: soluble rubber materials, soluble plastic materials, soluble metal-nonmetal composite materials, and particularly water-soluble rubber material products have strong market demands.
At present, however, the water-soluble rubber materials on the market are few, the performance is poor, and the rubber materials which can be dissolved in water controllably at a certain temperature and within a certain time have higher use value, but the product reports are rare.
Therefore, the existing water-soluble rubber materials need to be improved.
Disclosure of Invention
The invention provides a novel water-soluble rubber and a preparation method thereof, the water-soluble rubber has good solubility, has both strength and solubility, and solves the problem that the existing rubber cannot be dissolved or has poor solubility.
The technical scheme of the invention is realized as follows:
the invention provides a water-soluble rubber material which is mainly prepared from the following components in parts by weight:
10-70 parts of dimethylolpropionic acid modified polyurethane (DMPA-PU), 15-30 parts of ethylenediamine propanesulfonic acid modified chitosan (EPS-CS), 5-30 parts of carboxymethyl modified nano silicon dioxide, 5-40 parts of compatilizer, 0.3-2 parts of coupling agent, 0.1-1 part of antioxidant, 1-5 parts of softener, 0.3-3 parts of cross-linking agent, 0.3-3 parts of accelerator and 0.5-6 parts of sulfur.
In the formula, polyurethane which is easily hydrolyzed is used as a matrix, and a high-molecular elastomer chain segment of dimethylolpropionic acid is grafted, so that the main chain polyurethane has certain rubber elasticity and strength, and the grafted chain dimethylolpropionic acid has the characteristic of being dissolved in water. Meanwhile, the natural water-soluble material ethylenediamine propanesulfonic acid modified chitosan is added to initiate the water-soluble disintegration of the material, namely the material is very easy to absorb water at the initial stage of the dissolution, and the water absorption speed and the dissolution time can be controlled by controlling the proportion of different materials, so that the reduction speed of the rubber strength is controlled, the hydrolysis performance of the rubber is controlled, and a customized product is provided for customers in the military industry field and the petroleum field. The carboxymethyl modified nano silicon dioxide not only improves the water solubility, but also improves the strength of the rubber material by matching with the two components.
Wherein, the water absorption speed of the material can be increased by increasing the proportion of the ethylenediamine propanesulfonic acid modified chitosan, and the dissolution speed can be delayed by increasing the proportion of the dimethylolpropionic acid modified polyurethane. The strength retention rate of the material in the dissolving process can be ensured by adjusting the proportion of the carboxymethyl modified nano silicon dioxide.
Preferably, the compatibilizer is prepared by mixing, by weight, 1: 1-3: 1 polyvinyl alcohol grafted glycidyl methacrylate (PVA-g-GMA) and maleic anhydride grafted SBS, which is favorable for the compatibility and dispersion of the organic and inorganic components of dimethylolpropionic acid modified polyurethane, modified chitosan and carboxymethyl modified nano silicon dioxide.
Preferably, the number average molecular weight of the dimethylolpropionic acid-modified polyurethane resin is 0.5 to 12 ten thousand. The dimethylolpropionic acid modified polyurethane resin material with the molecular weight distribution has similar performance to common natural rubber and styrene butadiene rubber materials, and can meet the performance requirements of rubber materials in most application scenes.
Preferably, the ethylenediamine propanesulfonic acid modified chitosan product is granular or powder, the mesh number is 30-120 meshes, and the ethylenediamine propanesulfonic acid modified chitosan with the parameters has excellent dispersion performance and water absorption performance. Too low particle size is not beneficial to the dispersion of the particles in the elastic material, and too large particle size has poor water absorption effect and cannot achieve controllable dissolution effect.
Preferably, the carboxymethyl modified nano silicon dioxide is granular or powder, and the mesh number is 50-800 meshes. The optimized particle size can provide the optimal strength effect of the rubber, and the carboxymethyl modified rubber is favorable for improving the water dissolution effect.
Preferably, the coupling agent is a silane coupling agent or a zirconate coupling agent.
Preferably, the antioxidant consists of 1010, 168 and HP-136 in a weight ratio of 1:1.5: 1. The invention utilizes the synergistic effect of the three antioxidants, fully exerts the advantages of the antioxidants, provides excellent oxidation resistance for the rubber material dissolved in water, ensures the performance stability of the rubber material, prolongs the quality guarantee period of the rubber material, and avoids the influence on the service performance of the rubber material due to oxidative degradation in the processes of storage, transportation and use.
Preferably, the softener is one or a mixture of more than two of polyethylene wax, paraffin oil, naphthenic oil and vaseline.
Preferably, the crosslinking agent is an organic peroxide or sulfide crosslinking agent and the accelerator is a thiazole or thiuram accelerator. The selected organic peroxide or sulfide crosslinking agent has a certain crosslinking effect but is not violent in the system of the invention, the crosslinking strength is moderate, the rubber material is ensured to meet the requirement of use performance, and the water-soluble effect of the rubber material after use is not influenced.
The invention also provides a preparation method of the water-soluble rubber material, which comprises the following specific steps:
s1, adding dimethylolpropionic acid modified polyurethane, ethylenediamine propanesulfonic acid modified chitosan, carboxymethyl modified nano silicon dioxide, a compatilizer, a coupling agent, an antioxidant and a softener in corresponding parts by weight into an internal mixer or an open mill in sequence, mixing for 20-40min at the blending temperature of 25-35 ℃, and standing for 25-35h to obtain a material 1;
s2, taking out the material 1, putting the material into a granulating device for granulation or putting the material into a grinding device for grinding into powder with the particle size of 50-150 meshes to obtain a material 2;
s3, adding the material 2 into a mixer, sequentially adding the cross-linking agent, the accelerant and the sulfur in corresponding parts by weight, and stirring for 3-10min at the rotation speed of 300-500 rpm; and adding the mixed materials into a forming die, pressing the materials into a product at the pressure of 5-25MPa and the temperature of 150 ℃ and 220 ℃ for 10-30min, and obtaining the water-soluble rubber.
The invention has the beneficial effects that:
1. the water-soluble rubber provided by the invention adopts an easily-hydrolyzed material as a matrix, the high-molecular elastomer chain segment is grafted and modified to ensure that the rubber has certain rubber elasticity and strength, the main chain has the characteristic of water-solubility, the added natural easily-soluble material triggers the water-soluble disintegration of the material, the proportion of the material can be controlled to control the dissolution time and the strength retention rate, the dissolution in water is realized, a customized product is provided for customers in the military industry field and the petroleum field, and the water-soluble rubber has higher economic value and social value.
2. The water-soluble rubber material provided by the invention is convenient to construct, high in dissolving efficiency and capable of reducing the construction cost. The rubber component has good application prospect and huge market, and can be widely used for temporary functional rubber components or products in oil field underground, tunnels, subways, culverts, underwater engineering, offshore oil extraction, civil buildings and the like.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Example 1
The embodiment provides a preparation method of water-soluble rubber, which comprises the following specific steps:
step one, sequentially adding 50 parts of dimethylol propionic acid modified polyurethane, 20 parts of ethylenediamine propanesulfonic acid modified chitosan, 15 parts of polyvinyl alcohol grafted glycidyl methacrylate, 5 parts of maleic anhydride grafted SBS, 10 parts of carboxymethyl modified nano silicon dioxide, 0.5 part of coupling agent, 0.5 part of antioxidant and 2.5 parts of softener into an internal mixer or an open mill, mixing for 30 minutes at the blending temperature of 30 ℃, and standing for 30 hours to obtain a material 1;
and step two, taking the material 1 out of the internal mixer or the open mill, and granulating in a granulating device or grinding in a grinding device into a component with the particle size of 50-150 meshes. To obtain a material 2.
Step three, adding the material 2 into a high-speed mixer, rotating at the speed of 400rpm, then sequentially adding 0.5 part of cross-linking agent, 0.5 part of accelerant and 0.8 part of sulfur, and stirring for 5 minutes; adding the mixed materials into a forming die, pressing under the pressure of 15MPa and at the temperature of 180 ℃ for 20min to obtain the required product.
Example 2
The embodiment provides a preparation method of water-soluble rubber, which comprises the following specific steps:
step one, in an internal mixer or an open mill, sequentially adding 65 parts of dimethylolpropionic acid modified polyurethane, 15 parts of ethylenediamine propanesulfonic acid modified chitosan, 5 parts of polyvinyl alcohol grafted glycidyl methacrylate, 5 parts of maleic anhydride grafted SBS, 10 parts of carboxymethyl modified nano silicon dioxide, 0.5 part of coupling agent, 0.5 part of antioxidant and 2.5 parts of softener, mixing for 30 minutes at the blending temperature of 30 ℃, and standing for 30 hours to obtain a material 1;
and step two, taking the material 1 out of the internal mixer or the open mill, and granulating in a granulating device or grinding in a grinding device into a component with the particle size of 50-150 meshes. To obtain a material 2.
Step three, adding the material 2 into a high-speed mixer, rotating at the speed of 400rpm, then sequentially adding 0.5 part of cross-linking agent, 0.5 part of accelerant and 0.8 part of sulfur, and stirring for 5 minutes; adding the mixed materials into a forming die, pressing under the pressure of 15MPa and at the temperature of 180 ℃ for 20min to obtain the required product.
Example 3
The embodiment provides a preparation method of water-soluble rubber, which comprises the following specific steps:
step one, sequentially adding 20 parts of dimethylolpropionic acid modified polyurethane, 25 parts of ethylenediamine propanesulfonic acid modified chitosan, 20 parts of polyvinyl alcohol grafted glycidyl methacrylate, 10 parts of maleic anhydride grafted, 20 parts of carboxymethyl modified nano silicon dioxide, 0.8 part of coupling agent, 0.6 part of antioxidant and 2.5 parts of softener into an internal mixer or an open mill, mixing for 30 minutes at the blending temperature of 30 ℃, and standing for 30 hours to obtain a material 1;
and step two, taking the material 1 out of the internal mixer or the open mill, and granulating in a granulating device or grinding in a grinding device into a component with the particle size of 50-150 meshes. To obtain a material 2.
Step three, adding the material 2 into a high-speed mixer, rotating at the speed of 400rpm, then sequentially adding 0.5 part of cross-linking agent, 0.5 part of accelerant and 0.8 part of sulfur, and stirring for 5 minutes; adding the mixed materials into a forming die, pressing under the pressure of 15MPa and at the temperature of 180 ℃ for 20min to obtain the required product.
Comparative example 1
This example provides a method for preparing a water-soluble rubber as a comparative example, which comprises the following steps:
step one, adding 70 parts of common natural rubber, 5 parts of butadiene rubber, 10 parts of polyvinyl alcohol grafted glycidyl methacrylate, 5 parts of maleic anhydride grafted SBS, 10 parts of silicon dioxide, 0.5 part of coupling agent, 0.5 part of antioxidant and 2.5 parts of softener into an internal mixer or an open mill in sequence, mixing for 30 minutes at the blending temperature of 30 ℃, and standing for 30 hours to obtain a material 1;
and step two, taking the material 1 out of the internal mixer or the open mill, and granulating in a granulating device or grinding in a grinding device into a component with the particle size of 50-150 meshes. To obtain a material 2.
Step three, adding the material 2 into a high-speed mixer, rotating at the speed of 400rpm, then sequentially adding 0.5 part of cross-linking agent, 0.5 part of accelerant and 0.8 part of sulfur, and stirring for 5 minutes; adding the mixed materials into a forming die, pressing under the pressure of 15MPa and at the temperature of 180 ℃ for 20min to obtain the required product.
Example 4 Performance testing of Water-soluble rubber
The water-soluble rubbers prepared in examples 1-2 and comparative example 1 were divided into 3 groups, each group was subjected to the following performance tests, and the test method of the solubility performance was an enterprise standard method:
and taking a material sample piece with the thickness of 100mm x 2mm, and recording the relation between the weight loss of the sample and the time in high-pressure high-temperature water at the temperature of 70-120 ℃. The time at which the sample weight loss reached 50% wt was taken as the dissolution behavior of the material: the shorter the time, the more soluble the material is at the same temperature; the longer the time, the poorer the dissolution properties of the material.
The results of the water-soluble rubber testing are shown in the following table:
according to the test data, the water-soluble rubber prepared in the embodiments 1-3 is superior to the comparative example material in the aspects of mechanical strength and solubility, and is superior to or equal to the comparative example value in the aspects of temperature resistance, density, thermal aging performance and the like.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (8)
1. The water-soluble rubber material is characterized by being mainly prepared from the following components in parts by weight:
10-70 parts of dimethylolpropionic acid modified polyurethane (DMPA-PU), 15-30 parts of ethylenediamine propanesulfonic acid modified chitosan (EPS-CS), 5-30 parts of carboxymethyl modified nano silicon dioxide, 5-40 parts of compatilizer, 0.3-2 parts of coupling agent, 0.1-1 part of antioxidant, 1-5 parts of softener, 0.3-3 parts of cross-linking agent, 0.3-3 parts of accelerator and 0.5-6 parts of sulfur;
the number average molecular weight of the dimethylolpropionic acid modified polyurethane resin is 0.5-12 ten thousand; the ethylenediamine propanesulfonic acid modified chitosan product is granular or powder, and the mesh number is 30-120 meshes; the cross-linking agent is an organic peroxide or sulfide cross-linking agent.
2. The water-soluble rubber material according to claim 1, wherein the compatibilizer is prepared by mixing the components in a weight ratio of 1: 1-3: 1 polyvinyl alcohol grafted glycidyl methacrylate (PVA-g-GMA) and maleic anhydride grafted SBS.
3. The water-soluble rubber material as claimed in claim 1, wherein the carboxymethyl modified nano silica is in the form of particles or powder, and the mesh number is 50-800 mesh.
4. The water-soluble rubber material according to claim 1, wherein the coupling agent is a silane coupling agent or a zirconate coupling agent.
5. The water-soluble rubber material as claimed in claim 1, wherein the antioxidant is composed of 1010, 168 and HP-136 in a weight ratio of 1:1.5: 1.
6. The water-soluble rubber material according to claim 1, wherein the softening agent is one or a mixture of two or more of polyethylene wax, paraffin oil, naphthenic oil and vaseline.
7. The water-soluble rubber material according to claim 1, wherein the accelerator is a thiazole or thiuram accelerator.
8. A method for preparing the water-soluble rubber material according to any one of claims 1 to 7, which comprises the following specific steps:
s1, adding dimethylolpropionic acid modified polyurethane, ethylenediamine propanesulfonic acid modified chitosan, carboxymethyl modified nano silicon dioxide, a compatilizer, a coupling agent, an antioxidant and a softener in corresponding parts by weight into an internal mixer or an open mill in sequence, mixing for 20-40min at the blending temperature of 25-35 ℃, and standing for 25-35h to obtain a material 1;
s2, taking out the material 1, putting the material into a granulating device for granulation or putting the material into a grinding device for grinding into powder with the particle size of 50-150 meshes to obtain a material 2;
s3, adding the material 2 into a mixer, sequentially adding the cross-linking agent, the accelerant and the sulfur in corresponding parts by weight, and stirring for 3-10min at the rotation speed of 300-500 rpm; and adding the mixed materials into a forming die, pressing the materials into a product at the pressure of 5-25MPa and the temperature of 150 ℃ and 220 ℃ for 10-30min, and obtaining the water-soluble rubber.
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| WO2011012857A2 (en) * | 2009-07-29 | 2011-02-03 | Halliburton Energy Services, Inc. | Weighted elastomers, cement compositions comprising weighted elastomers, and methods of use |
| CN102070896A (en) * | 2010-06-23 | 2011-05-25 | 上海长宁橡胶制品厂 | Water swellable rubber and production method thereof |
| CN102453266A (en) * | 2010-10-22 | 2012-05-16 | 中国石油化工股份有限公司 | High-strength hydrophilic expansion rubber and preparation method thereof |
| CN104246115A (en) * | 2012-04-16 | 2014-12-24 | 瑞翁化工公司 | High temperature stable water swellable rubber composition |
| CN104558748A (en) * | 2013-10-24 | 2015-04-29 | 青岛华泓星塑胶有限公司 | Water-soluble environment-friendly rubber plastic |
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- 2018-12-29 CN CN201811638963.9A patent/CN109762322B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011012857A2 (en) * | 2009-07-29 | 2011-02-03 | Halliburton Energy Services, Inc. | Weighted elastomers, cement compositions comprising weighted elastomers, and methods of use |
| CN102070896A (en) * | 2010-06-23 | 2011-05-25 | 上海长宁橡胶制品厂 | Water swellable rubber and production method thereof |
| CN102453266A (en) * | 2010-10-22 | 2012-05-16 | 中国石油化工股份有限公司 | High-strength hydrophilic expansion rubber and preparation method thereof |
| CN104246115A (en) * | 2012-04-16 | 2014-12-24 | 瑞翁化工公司 | High temperature stable water swellable rubber composition |
| CN104558748A (en) * | 2013-10-24 | 2015-04-29 | 青岛华泓星塑胶有限公司 | Water-soluble environment-friendly rubber plastic |
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