CN109912839B - Surface treatment method of buoyancy material - Google Patents
Surface treatment method of buoyancy material Download PDFInfo
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- CN109912839B CN109912839B CN201910242631.7A CN201910242631A CN109912839B CN 109912839 B CN109912839 B CN 109912839B CN 201910242631 A CN201910242631 A CN 201910242631A CN 109912839 B CN109912839 B CN 109912839B
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Abstract
The invention relates to a surface treatment method of a buoyancy material, which comprises the steps of fixing the buoyancy material to be treated in a container, placing the container under a pouring gate in a vacuum pouring tank, and vacuumizing; pouring epoxy resin, reactive diluent, coupling agent and surfactant into a mixing tank, uniformly stirring at room temperature and defoaming in vacuum; adding a curing agent and a curing accelerator, and stirring uniformly at room temperature; opening a feed opening valve of the mixing tank, and allowing the resin mixed solution to flow into a container of the buoyancy material, wherein the liquid level is 2-3cm higher than the upper surface of the material; opening an air inlet of a vacuum casting tank, increasing the air pressure in the tank to 20000Pa, maintaining the pressure for 5 minutes and then releasing the pressure; washing with absolute alcohol until no resin remains on the surface, and keeping the temperature at 80 ℃ for 12 hours. By adopting the process, the water absorption of the material can be reduced to be below 0.1%, and the density of the material is not influenced; even if the surface is damaged to a certain degree, the water absorption rate can still be kept about 0.5 percent, and the reliability of the floating body is greatly improved.
Description
Technical Field
The invention belongs to the technical field of composite materials, and particularly relates to a surface treatment method of a buoyancy material.
Background
Along with the continuous increase of activities such as marine resource development, marine engineering and the like in China, the use amount of various buoyancy compensation materials is also increased year by year, and the buoyancy compensation materials are widely applied to the fields of underwater robots, deep submergence vehicles, offshore oil platforms, underwater construction and the like. Among the numerous performance indexes of the buoyancy material, the water absorption rate is related to the stability of the net buoyancy of the buoyancy material, the reliability of the floating body, the service life and other factors, and is an important index of the product. At present, a composite Foam type (synthetic Foam) buoyancy material has a series of advantages of high compressive strength, good processability, high elastic modulus and the like, and becomes a buoyancy material product which is the most extensive in application field. At present, a die forming method is a forming process which is widely applied in the production of composite foam type buoyancy materials, although the forming process has a series of advantages of low product density, simple process and the like, the water absorption of a bare material of the product is higher than that of the product prepared by processes such as a vacuum casting method, a vacuum impregnation method and the like, the phenomenon is particularly prominent in low-density products, and adverse effects can be brought to the net buoyancy of the material, the reliability of the product and the service life of the product.
The spraying of waterproof paint is a common protection means in ocean engineering. In underwater structures and equipment, the epoxy type coating, the polyurea type waterproof coating and the like are widely applied. Because underwater equipment needs to frequently float up and submerge, the underwater equipment is stored in a non-working state, belongs to a marine atmospheric corrosion environment and is easy to be directly irradiated by sunlight, and the aging speed of the waterproof layer is very high in the complex environment; in addition, the underwater equipment is often impacted by external force during storage, hoisting and working, and the waterproof layer can be damaged. Once the waterproof layer is invalid, the buoyancy material will lead to net buoyancy to descend because of absorbing water, brings the potential safety hazard for the use of underwater equipment. In addition, since the bulk density of the water barrier is significantly higher than the bulk density of the float, the overall density of the buoyant material after the coating is applied is also affected. Because the epoxy/polyurea waterproof layer is constructed by adopting a spraying method, the problems of difficult construction, uneven thickness of the waterproof layer and the like exist for buoyancy with complex appearance.
In the middle of the 90 s, the solid buoyancy material prepared by the chemical foaming method in the marine chemical research institute adopts an epoxy resin glass fiber reinforced plastic waterproof layer which has the defects of high brittleness, poor toughness, easiness in cracking, easiness in aging and the like. Chinese patent publication No. CN1401717, "polyurea coating for spraying of solid buoyant material", also reports a method of spraying polyurea coating on the surface of a floating body to improve the water resistance of the floating body, but the coating has poor wetting ability on the surface of the buoyant material substrate and is easy to peel; poor ultraviolet resistance and easy aging; the construction method is generally spraying, so the method is not suitable for some floating bodies with complicated shapes.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a surface treatment method of a buoyancy material, which takes epoxy resin, a diluent, a surfactant, a coupling agent, a curing accelerator and the like as raw materials and adopts a vacuum/pressure-assisted special process to carry out surface treatment on the buoyancy material. The process has convenient construction and lower cost, does not increase the density of the floating body, and is not easy to age; the processed buoyancy block not only has greatly reduced water absorption rate, but also can keep the water absorption rate at a lower level after the surface is damaged to a certain degree, has obviously better reliability than the traditional epoxy/polyurea waterproof layer, can effectively improve the net buoyancy stability, reliability and service life of the buoyancy material, and has very high practical value.
The invention is realized in such a way that the surface treatment method of the buoyancy material comprises the following steps:
1) fixing the buoyancy material to be treated in a container, placing the container under a pouring gate in a vacuum pouring tank, and then vacuumizing;
2) pouring 100 parts of epoxy resin, 30-45 parts of reactive diluent, 2 parts of coupling agent and 0.5 part of surfactant into a mixing tank of a vacuum casting tank, uniformly stirring at room temperature, and defoaming for 15 minutes in a vacuum state; then adding 12-18 parts of curing agent and 0.5 part of curing accelerator, and stirring uniformly at room temperature;
3) opening a feed opening valve of the mixing tank, and allowing the resin mixed solution to flow into a container filled with the buoyancy material until the liquid level is 2-3cm higher than the upper surface of the buoyancy material; opening an air inlet of the vacuum casting tank, increasing the air pressure in the vacuum casting tank to 20000Pa by using an air compressor, maintaining the pressure for 5 minutes and then releasing the pressure;
4) taking out the floating body, washing the floating body with absolute ethyl alcohol until no residual resin is on the surface of the floating body, putting the floating body into an oven at 80 ℃ for heat preservation for 12 hours, and naturally cooling the floating body for use.
The steps 1) to 4) can be repeated according to specific conditions so as to ensure the surface treatment effect of the floating body.
In the above technical solution, preferably, in the step 1), the edge of the container is at least 5cm higher than the upper surface of the buoyant material.
In the above technical solution, preferably, in the steps 1) and 2), the pressure of the vacuum is lower than 1000 Pa.
In the above technical solution, preferably, the epoxy resin is bisphenol a type epoxy resin.
In the above technical solution, it is further preferable that the epoxy resin is an E51 type epoxy resin.
In the above technical solution, preferably, the reactive diluent is butyl glycidyl ether.
In the above technical solution, preferably, the surfactant is Disponer 904S.
In the above technical solution, preferably, the coupling agent is γ -aminopropyltriethoxysilane.
In the above technical solution, preferably, the curing agent is a fatty amine curing agent.
In the above technical solution, it is further preferable that the curing agent is (2,3 dimethyl) dibutylenetriamine.
In the above technical solution, preferably, the curing accelerator is tris- (dimethylaminomethyl) phenol.
The air holes in the material are an important reason for causing the buoyancy material to absorb water, and the coating of the waterproof layer is a common means for reducing the water absorption rate of the buoyancy material at present. However, since the waterproof layer is attached only to the surface of the buoyant material, the use effect of the waterproof layer is greatly reduced when the waterproof layer is damaged due to external impact or aging. The invention adjusts the viscosity and surface property of the resin solution, and uses the pressure difference between the inside and the outside of the pore to lead the resin solution to penetrate into the pores in the material and form effective filling, thus achieving the effect of reducing the water absorption rate.
According to the on-way pressure loss calculation formula:
in the formula: delta Pf-on-way pressure loss, λ -viscosity coefficient, l-penetration depth, d-capillary diameter, ρ -liquid density, v-penetration velocity.
From the above equation for calculating the on-way pressure loss, the permeation of the resin solutionPenetration depth l and pressure drop Δ P at equilibriumfThe pressure difference between the inside and the outside is in direct proportion, and the pressure difference is in inverse proportion to the interfacial friction coefficient lambda, the permeation speed v and the like. Thus can be increased by increasing Δ PfAnd adjusting the interface characteristics (reducing lambda), and the like, and increasing the penetration depth of the resin solution to the pores so as to improve the surface treatment effect and reliability.
The invention takes epoxy resin, diluent, surfactant, coupling agent, curing agent and curing accelerator as raw materials, the compositions of the raw materials and the base body (also a resin system) of the buoyancy material are basically consistent, and the raw materials are cured after entering the floating body, thereby playing a role in plugging through pores. When the resin mixed solution is prepared, the diluent, the surfactant and the coupling agent are added firstly, and the curing agent and the curing accelerator are added, so that the defoaming effect and the stability of the process can be ensured, and the problems that the viscosity of the resin is increased and the subsequent process is unstable due to the fact that the resin is possibly cured in the stirring and defoaming processes because all the components are added at one time are solved; the purpose of adding the diluent and the surfactant is to adjust the viscosity of the resin and improve the wetting effect of the resin on the walls of capillary pores; the coupling agent is added to ensure the bonding strength of the resin and the capillary hole wall; the curing agent and the curing accelerator are added to adjust the curing characteristics of the resin. Designing a resin formula capable of effectively penetrating into air holes in the floating body by adjusting the viscosity of the resin, the wetting property of the resin on the surface of the floating body material, the curing property and the like; and a special vacuum/pressure auxiliary process is adopted, air in the air holes of the buoyancy material is fully pumped out firstly, the air is prevented from hindering the infiltration and the penetration of resin to the inside of the air holes, and then the penetration depth of the resin is increased under a positive pressure environment, so that the effect of sealing the air holes of the buoyancy material and reducing the water absorption rate of the buoyancy material is achieved.
Compared with the waterproof treatment process of the buoyancy material, the process has the advantages of convenient construction and lower cost; the resin solution permeates into the pores of the material under the action of pressure difference to form effective closure, so that the water absorption of the material can be effectively reduced; experiments prove that even if the surface of the material is damaged to a certain degree, the water absorption rate of the material can still be kept at a lower level of about 0.5 percent; since the amount of resin penetrating into the interior of the material along the pores is very low, the surface treatment has little effect on the density of the buoyant material; finally, the surface treatment can also reinforce the defective part on the surface of the buoyancy material, thereby improving the adhesion strength of the waterproof layer and the buoyancy material, prolonging the service life of the waterproof layer and achieving multiple purposes.
The invention has the advantages and positive effects that:
1) the buoyancy material is treated by adopting the process, so that the water absorption of the material can be reduced to be below 0.1 percent, which is far lower than the water absorption index of the existing buoyancy material bare material, and the volume density of the material is not influenced; even if the surface is damaged to a certain degree, the water absorption rate can still be kept at a lower level of about 0.5 percent, and the reliability of the floating body is greatly improved;
2) the surface of the floating body treated by the process is hard and rough, so that the adhesion strength of the epoxy/polyurea coating and the base material is improved, the reliability of the waterproof layer can be improved, and the service life of the waterproof layer can be prolonged;
3) compared with the traditional spraying of an epoxy or polyurea waterproof layer, the treatment process has the advantages of convenience in construction, wide applicability, high reliability, no increase in floating body density and the like, can obviously reduce the water absorption rate of the buoyancy material, improve the reliability and prolong the service life of the buoyancy material, can be widely applied to the treatment of the buoyancy material in the fields of ocean engineering, underwater robots, ocean oil and gas exploitation and the like, and has high use value.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1:
a surface treatment method of a buoyancy material comprises the following steps:
1) fixing a buoyancy material to be treated in a container, placing the container under a pouring gate in a vacuum pouring tank, and then vacuumizing, wherein the vacuum pressure is lower than 1000 Pa;
2) pouring 100 parts of E51 type epoxy resin, 30 parts of butyl glycidyl ether, 2 parts of gamma-aminopropyltriethoxysilane and 0.5 part of Disponer 904S into a mixing tank of a vacuum pouring tank, stirring for 10 minutes at room temperature, and then defoaming for 15 minutes in a vacuum state, wherein the vacuum pressure is lower than 1000 Pa; then 12 parts of (2, 3-dimethyl) dibutylenetriamine and 0.5 part of tris- (dimethylaminomethyl) phenol are added and stirred for 5 minutes at room temperature;
3) opening a feed opening valve of the mixing tank, and allowing the resin mixed solution to flow into a container filled with the buoyancy material until the liquid level is 2-3cm higher than the upper surface of the buoyancy material; opening an air inlet of the vacuum casting tank, increasing the air pressure in the vacuum casting tank to 20000Pa by using an air compressor, maintaining the pressure for 5 minutes and then releasing the pressure;
4) taking out the floating body, washing the floating body with absolute ethyl alcohol until no residual resin is on the surface of the floating body, putting the floating body into an oven at 80 ℃ for heat preservation for 12 hours, and naturally cooling the floating body for use.
Example 2:
example 2 differs from example 1 in that, in step 2), the resin mixture is prepared as follows: 100 parts of epoxy resin E51, 30 parts of butyl glycidyl ether, 2 parts of gamma-aminopropyltriethoxysilane, 0.5 part of Disponer 904S, 15 parts of (2, 3-dimethyl) dibutylenetriamine and 0.5 part of tris- (dimethylaminomethyl) phenol.
Example 3:
example 3 differs from example 1 in that, in step 2), the resin mixture is prepared as follows: 100 parts of epoxy resin E51, 30 parts of butyl glycidyl ether, 2 parts of gamma-aminopropyltriethoxysilane, 0.5 part of Disponer 904S, 18 parts of (2, 3-dimethyl) dibutylenetriamine and 0.5 part of tris- (dimethylaminomethyl) phenol.
Example 4:
example 4 differs from example 1 in that, in step 2), the resin mixture is prepared as follows: 100 parts of epoxy resin E51, 45 parts of butyl glycidyl ether, 2 parts of gamma-aminopropyltriethoxysilane, 0.5 part of Disponer 904S, 12 parts of (2, 3-dimethyl) dibutylenetriamine and 0.5 part of tris- (dimethylaminomethyl) phenol.
Example 5:
example 5 differs from example 1 in that, in step 2), the resin mixture is prepared as follows: 100 parts of epoxy resin E51, 45 parts of butyl glycidyl ether, 2 parts of gamma-aminopropyltriethoxysilane, 0.5 part of Disponer 904S, 15 parts of (2, 3-dimethyl) dibutylenetriamine and 0.5 part of tris- (dimethylaminomethyl) phenol.
Example 6:
example 6 differs from example 1 in that, in step 2), the resin mixture is prepared as follows: 100 parts of epoxy resin E51, 45 parts of butyl glycidyl ether, 2 parts of gamma-aminopropyltriethoxysilane, 0.5 part of Disponer 904S, 18 parts of (2, 3-dimethyl) dibutylenetriamine and 0.5 part of tris- (dimethylaminomethyl) phenol.
The buoyant materials to be treated used in the above examples 1-6 were treated with the self-made buoyant material having a size of 5cm × 5cm × 10cm and a bulk density of 0.38g/cm3The water absorption of the bare material was 1.32%.
The buoyancy materials of examples 1-6 after surface treatment were subjected to various performance tests: including water absorption tests, and water absorption tests after surface failure. The test results are shown in table 1.
The test methods for the properties are as follows:
1) water absorption: the original mass m of the sample subjected to surface treatment is measured0Putting the sample into a pressure experimental device, pressurizing to 3MPa, maintaining the pressure for 24 hours, taking out the sample, wiping off the water on the surface of the sample, and weighing the mass m of the sample1. The water absorption was calculated as follows:
water absorption rate of (m)1-m0)/m0×100％
2) Water absorption after surface breakage: firstly, processing a groove with the length of about 50mm, the width of 2mm and the depth of 1mm on the surface of a sample subjected to surface treatment, and then measuring the quality M of the processed sample0Putting the sample into a pressure experimental device, pressurizing to 3MPa, maintaining the pressure for 24 hours, taking out the sample, wiping off the surface moisture of the sample, and weighing the mass M of the sample1. Surface water absorption to failure was calculated as follows:
surface water absorption for failure (M)1-M0)/M0×100％
Table 1 examples 1-6 tests and results
As can be seen from Table 1, the buoyancy material treated by the surface treatment method for the buoyancy material provided by the invention can reduce the water absorption of the material to be below 0.1%, which is far lower than the water absorption index of the existing bare buoyancy material, and the volume density of the material is hardly influenced; even if the surface is damaged to a certain degree, the water absorption rate can still be kept at a low level of about 0.5 percent, and the reliability of the floating body is greatly improved.
Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: it is to be understood that modifications may be made to the technical solutions described in the foregoing embodiments, or some or all of the technical features may be equivalently replaced, and the modifications or the replacements may not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.
Claims (10)
1. A surface treatment method of a buoyancy material is characterized in that: the method comprises the following steps:
1) fixing the buoyancy material to be treated in a container, placing the container under a pouring gate in a vacuum pouring tank, and then vacuumizing;
2) pouring 100 parts of epoxy resin, 30-45 parts of reactive diluent, 2 parts of coupling agent and 0.5 part of surfactant into a mixing tank of a vacuum casting tank, uniformly stirring at room temperature, and defoaming for 15 minutes in a vacuum state; then adding 12-18 parts of curing agent and 0.5 part of curing accelerator, and stirring uniformly at room temperature;
3) opening a feed opening valve of the mixing tank, and allowing the resin mixed solution to flow into a container filled with the buoyancy material until the liquid level is 2-3cm higher than the upper surface of the buoyancy material; opening an air inlet of the vacuum casting tank, increasing the air pressure in the vacuum casting tank to 20000Pa by using an air compressor, maintaining the pressure for 5 minutes and then releasing the pressure;
4) taking out the floating body, washing the floating body with absolute ethyl alcohol until no residual resin is on the surface of the floating body, putting the floating body into an oven at 80 ℃ for heat preservation for 12 hours, and naturally cooling the floating body for use.
2. A surface treatment method for a buoyant material according to claim 1 wherein: in the step 1), the edge of the container is at least 5cm higher than the upper surface of the buoyant material.
3. A surface treatment method for a buoyant material according to claim 1 wherein: in the steps 1) and 2), the pressure of the vacuum is lower than 1000 Pa.
4. A surface treatment method for a buoyant material according to claim 1 wherein: the epoxy resin is bisphenol A type epoxy resin.
5. A surface treatment method for a buoyant material according to claim 4 wherein: the epoxy resin is E51 type epoxy resin.
6. A surface treatment method for a buoyant material according to claim 1 wherein: the reactive diluent is butyl glycidyl ether.
7. A surface treatment method for a buoyant material according to claim 1 wherein: the surfactant is Disponer 904S.
8. A surface treatment method for a buoyant material according to claim 1 wherein: the coupling agent is gamma-aminopropyl triethoxysilane.
9. A surface treatment method for a buoyant material according to claim 1 wherein: the curing agent is (2,3 dimethyl) dibutylene triamine.
10. A surface treatment method for a buoyant material according to claim 1 wherein: the curing accelerator is tris- (dimethylaminomethyl) phenol.
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| CN1563134A (en) * | 2004-04-07 | 2005-01-12 | 海洋化工研究院 | Solid buoyancy material prepared through chemical blowing process |
| CN101270220A (en) * | 2008-04-30 | 2008-09-24 | 海洋化工研究院 | Method for preparing polyalcohol-base light overpressure resistant floating force material and equipment thereof |
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| KR101585556B1 (en) * | 2013-07-09 | 2016-01-14 | 가부시키가이샤 에스이 | Method for manufacturing high-strength cement cured product |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1563134A (en) * | 2004-04-07 | 2005-01-12 | 海洋化工研究院 | Solid buoyancy material prepared through chemical blowing process |
| CN101270220A (en) * | 2008-04-30 | 2008-09-24 | 海洋化工研究院 | Method for preparing polyalcohol-base light overpressure resistant floating force material and equipment thereof |
Non-Patent Citations (1)
| Title |
|---|
| 碳纳米管改性泡沫镍/环氧树脂复合材料阻尼性能;谢北萍等;《复合材料学报》;20170630;第34卷(第6期);1325-1333 * |
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