Silicone emulsions, preparation and methods for dehydrating and shaping waterlogged wooden artifacts

Abstract

The application discloses an organic silicon emulsion, a preparation method and a method for dehydrating and shaping water-saturated wooden cultural relics, and relates to the field of water-saturated wooden cultural relic protection research.The preparation method of the organic silicon emulsion comprises the following steps: taking 2-5 parts of organic silicon monomer, 1-3 parts of a surfactant, 0.3-1 parts of a co-surfactant and 3-6 parts of pure water for standby; the surfactant and the co-surfactant are added into the organic silicon monomer, and uniform stirring or oscillation is continuously carried out to form a transparent organic silicon dispersion liquid; and the organic silicon dispersion liquid is poured into the pure water, and sufficient stirring or oscillation is carried out to form a stable organic silicon emulsion.The organic silicon emulsion material prepared by the application has good dehydrating and shaping performance, and can significantly enhance the dimensional stability, mechanical properties, microbial resistance and environmental stability of the cultural relics, and is environment-friendly and efficient.

Description

Technical Field

[0001] This invention relates to the field of research on the preservation of waterlogged wooden artifacts, and in particular to an organosilicon emulsion, its preparation method, and its application in the dehydration and shaping of waterlogged wooden artifacts. Background Technology

[0002] Waterlogged wooden artifacts are subjected to various physical, chemical, and biological factors in underwater environments, resulting in severe degradation and loss of cell wall components. Numerous pores and microcracks appear in the cell walls, and the microfibril structure becomes loose, leading to a significant decline in the mechanical properties of the archaeological wood. During degradation, the breakage of cellulose molecular chains in the cell walls of the wooden artifacts generates a large number of hydrophilic hydroxyl groups, causing greater stress during water migration within the wood. This further collapses the already fragile cell walls, leading to shrinkage, deformation, and even cracking after dehydration. Considering the structural characteristics and water migration patterns of waterlogged wooden artifacts, using appropriate chemical materials to fill the pores in the cell walls, seal the hydroxyl groups, and enhance the mechanical strength of the cell walls is an effective means to resist volume shrinkage and maintain dimensional stability during water evaporation. Literature reports dehydration and shaping materials for waterlogged wooden artifacts including alum, sucralose, trehalose, polyethylene glycol (PEG), glyoxal, erythritol, and organosilicon, with PEG being the most commonly used in large-scale wooden artifact conservation projects.

[0003] When using organosilicon materials for dehydration and shaping of waterlogged wooden artifacts, the artifacts must first undergo pre-dehydration treatment. This involves using organic solvents such as ethanol and acetone to gradually replace the moisture in the wood through a concentration gradient impregnation method. Then, an organosilicon alcohol solution is used for gradual impregnation from low to high concentrations, allowing the organosilicon to penetrate the interior of the wooden artifact. While this method achieves dehydration and shaping, it has the following significant drawbacks: ① Gradient impregnation is time-consuming, often lasting months or even years, resulting in low efficiency; ② It requires the use of large amounts of flammable organic solvents, posing safety hazards and creating problems with organic waste disposal; ③ The initial stage of the organosilicon sol-gel reaction requires the participation of water, making it highly sensitive to residual moisture in the wood. Improper pre-dehydration makes it difficult to control the polymerization rate of the organosilicon later, leading to poor reinforcement effects. To address these bottlenecks, researchers both domestically and internationally have explored the processes and effects of using various organosilicon materials for dehydrating waterlogged wooden artifacts, but an effective solution has yet to be found. ([1] Tong Hua, Li Meiying, Zhen Guangquan, et al. Study on dehydration, shaping and consolidation of waterlogged wooden cultural relics by organosilicon sol-gel method [J]. Jianghan Archaeology, 2014(S1):60-68. [2] Broda M, Mazela B, Dutkiewicz A. Organosilicon compounds with various active groups as consolidants for the preservation of waterlogged archaeological wood [J]. Journal of Cultural Heritage, 2019, 35:123-128.) Summary of the Invention

[0004] To address the above problems, this invention provides an organosilicon emulsion, its preparation method, and its application in the dehydration and shaping of waterlogged wooden artifacts. The method utilizes a surfactant-co-surfactant composite emulsification system to prepare a water-soluble O / W emulsion from hydrophobic organosilicon monomers, which is then directly applied to the waterlogged wooden artifacts. This eliminates the need for pre-dehydration, avoids the use of large amounts of organic reagents, and significantly shortens the dehydration and shaping time. A catalyst is used to initiate the polymerization reaction, allowing the organosilicon polymer to directionally adhere to the cell walls of the wooden artifacts. By sealing the hydrophilic groups on the cell walls and supporting and strengthening them, this process achieves shaping and reinforcement during the dehydration of the waterlogged wooden artifacts. The organosilicon emulsion material prepared by this method exhibits excellent dehydration and shaping performance, significantly enhancing the dimensional stability, mechanical properties, microbial resistance, and environmental stability of the artifacts, making it environmentally friendly and efficient.

[0005] This invention is achieved through the following technical solution:

[0006] According to a first aspect of the present invention, a method for preparing an organosilicon emulsion is provided, comprising the following steps:

[0007] (1) Take 2-5 parts of organosilicon monomer, 1-3 parts of surfactant, 0.3-1 parts of co-surfactant, and 3-6 parts of pure water for later use;

[0008] (2) Add surfactant and co-surfactant to the organosilicon monomer, and stir or shake continuously until uniform to form a transparent organosilicon dispersion.

[0009] (3) Pour the organosilicon dispersion into pure water and stir or shake thoroughly to form a stable organosilicon emulsion.

[0010] Furthermore, the organosilicon monomer is one or more of the following materials: dodecyltrimethoxysilane, bistriethoxysilane, bistriethoxysiloxane, polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

[0011] Further, the surfactant is one or more of the following materials: fatty acid polyoxyethylene ester, triphenylethylphenol polyoxyethylene ether, polyoxyethylene hydrogenated castor oil, fatty alcohol polyoxyethylene ether phosphate, alkylphenol polyoxyethylene ether, octadecyltrimethylammonium chloride, and hexadecyltrimethylammonium chloride.

[0012] Further, the co-surfactant is one or more of the following materials: ethanol, isopropanol, polyethylene glycol, 1-hexanol, p-nonylphenol, and polyethylene glycol monobutyl ether.

[0013] Furthermore, the organosilicon monomer has a mass fraction of 20% to 50%, the surfactant has a mass fraction of 10% to 30%, and the co-surfactant has a mass fraction of 3% to 10%.

[0014] According to a second aspect of the present invention, an organosilicon emulsion prepared by the preparation method described in any of the above aspects is provided.

[0015] According to a third aspect of the present invention, a method for dehydrating and shaping waterlogged wooden artifacts using the organosilicon emulsion described above is provided, characterized by comprising the following steps:

[0016] (1) Emulsion penetration step: Immerse the water-saturated wooden artifact in an organosilicon emulsion until the weight of the water-saturated wooden artifact is constant;

[0017] (2) Catalytic initiation step: Add an appropriate amount of catalyst to the organosilicon emulsion to initiate the polymerization reaction of the organosilicon emulsion;

[0018] (3) Polymerization and drying step: After the viscosity of the silicone emulsion increases (to about 200 mPa·S or more), the water-saturated wooden artifact is taken out from the silicone emulsion, the residual emulsion on the surface is removed, and the water-saturated wooden artifact is dried, thereby completing the dehydration and shaping of the water-saturated wooden artifact.

[0019] Furthermore, the maximum moisture content of the waterlogged wooden artifact is 320%-820%.

[0020] Furthermore, the auxiliary processes for impregnating water-saturated wooden artifacts with silicone emulsion in step (1) include full immersion, semi-immersion, spraying, injection, and drip infiltration.

[0021] Furthermore, in step (1), the amount of organosilicon emulsion used is 1 to 4 times the volume of the water-saturated wooden artifact being treated, and is adjusted according to the maximum water content of the water-saturated wooden artifact.

[0022] Furthermore, the catalyst selected in step (2) is one of the following materials: dibutyltin dilaurate, triethylenetetramine, octylamine, and (3-aminopropyl)triethoxysilane.

[0023] Furthermore, the amount of catalyst used in step (2) is 0.5% to 2%.

[0024] Furthermore, the method for removing residual emulsion in step (3) can be by spraying with pure water, gently brushing or wiping.

[0025] Furthermore, the drying method in step (3) can be natural drying indoors, slow drying after wrapping with plastic film and punching holes, slow drying in a high humidity environment, or drying in a constant temperature and humidity chamber.

[0026] The beneficial effects of this invention are:

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] ① The prepared organosilicon emulsion can directly penetrate into the interior of water-saturated wooden artifacts without the need for pre-dehydration of the wooden artifacts, thus avoiding the use of a large amount of organic reagents, greatly shortening the dehydration and shaping time, and being environmentally friendly and efficient.

[0029] ② The selected organosilicon monomers have good permeability and polymerization properties. The porous gel formed after curing at room temperature and pressure has good air permeability, mechanical properties, aging resistance and waterproofness.

[0030] ③ The polymerization rate is controllable, and the generated organosilicon polymer is directionally attached to the wood cell wall, which plays a role in supporting and reinforcing the cell wall. It does not fill the cell cavity in large quantities, leaving space for future reprocessing, which is in line with the principle of reprocessable cultural relics protection.

[0031] ④ The weight gain of the treated water-saturated wooden artifacts is less than 200%, which is about 50% of that of commonly used PEG. The three-dimensional shrinkage rate of the wood is less than 3%, and the saturated moisture absorption weight gain rate at 95% RH is 8%, which is much lower than PEG's 80%. That is, it has good dimensional stability and superior moisture resistance under a lower reinforcement material load, showing significant technical advantages. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the operation process of the method for using the organosilicon emulsion of the present invention to dehydrate and shape waterlogged wooden cultural relics.

[0033] Figure 2 These are photographs of the waterlogged wooden artifact sample before and after dehydration in Embodiment 2 of the present invention. (a) Before dehydration; (b) After dehydration.

[0034] Figure 3 The image shows a cross-sectional micrograph and EDS energy dispersive spectroscopy (EDS) scan of the dehydrated waterlogged wooden artifact sample in Example 2 of this invention (a) and a comparison with the naturally dried sample (b).

[0035] Figure 4 This is the water vapor adsorption-desorption curve of the water-saturated wooden artifact sample after dehydration and shaping with organosilicon emulsion in Example 2 of the present invention, and its comparison with the naturally dried sample and the sample dehydrated by the existing PEG method. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0037] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0038] Organosilicon materials possess the dual properties of both organic and inorganic materials. They can form porous network polymers through sol-gel reactions under normal temperature and pressure, exhibiting outstanding advantages such as high strength, aging resistance, microbial resistance, and high environmental stability. Furthermore, the preparation process is highly adjustable, making it a promising material for the preservation of wooden artifacts. The contradiction lies in the fact that organosilicon materials are generally poorly soluble in water and sensitive to moisture. However, saturated wooden artifacts are characterized by a high moisture content, typically between 180% and 500%, and sometimes reaching 800% to 1000%. The pores within saturated wooden artifacts are completely occupied by water, preventing the water-repellent organosilicon materials from penetrating the wood. Upon encountering surface moisture, they initiate a polymerization reaction, leading to uncontrollable and ineffective dehydration and shaping processes, and even causing cracking and plasticization on the artifact's surface. Existing organosilicon dehydration methods require prolonged immersion in large amounts of organic solutions such as ethanol to displace the moisture in the wood, which is inefficient and highly dangerous. By using an emulsification process, water-repellent organosilicon monomers are coated into microspheres composed of surfactants to produce water-soluble oil-in-water (O / W) type organosilicon emulsions. This allows organosilicon to directly penetrate and replace water in water-saturated wooden artifacts, effectively improving the wettability of organosilicon with water-saturated wooden artifacts. It also allows organosilicon to be directionally adsorbed onto the wood cell walls, undergoing in-situ polymerization. By supporting the cell walls and blocking hydroxyl groups, it achieves the purpose of dehydration and shaping.

[0039] Therefore, the present invention provides a method for preparing an organosilicon emulsion, comprising the following steps:

[0040] (1) Raw material preparation steps: Take 2-5 parts of organosilicon, 1-3 parts of surfactant, 0.3-1 parts of co-surfactant, and 3-6 parts of pure water for later use;

[0041] (2) Preparation steps of organosilicon dispersion: Add surfactant and co-surfactant to organosilicon monomer, stir or shake continuously until uniform, and form transparent organosilicon dispersion.

[0042] (3) Organosilicon emulsification step: Pour the organosilicon dispersion into pure water and stir or shake thoroughly to form a stable emulsion.

[0043] Further, the organosilicon monomer in step (1) is one or more of the following materials: dodecyltrimethoxysilane, bistriethoxysilane, bistriethoxysiloxane, polydimethylsiloxane, and hydroxyl-terminated polydimethylsiloxane.

[0044] Further, the surfactant in step (1) is one or more of the following materials: fatty acid polyoxyethylene ester, triphenylethylphenol polyoxyethylene ether, polyoxyethylene hydrogenated castor oil, fatty alcohol polyoxyethylene ether phosphate, alkylphenol polyoxyethylene ether, octadecyltrimethylammonium chloride, and hexadecyltrimethylammonium chloride.

[0045] Further, the co-surfactant in step (1) is one or more of the following materials: ethanol, isopropanol, polyethylene glycol, 1-hexanol, p-nonylphenol, and polyethylene glycol monobutyl ether.

[0046] Here, dodecyltrimethoxysilane, bis(triethoxysilane), and bis(triethoxysiloxane) significantly improve the mechanical strength and surface hardness of waterlogged wooden artifacts; polydimethylsiloxane and hydroxyl-terminated polydimethylsiloxane enhance the toughness of both the polymer and the waterlogged wooden artifacts, effectively preventing cracking of fragile wood with high moisture content. These two types of organosilicon monomers can be used alone or in combination, depending on the dehydration and reinforcement requirements of the waterlogged wooden artifacts, to achieve the best results. The surfactants are formulated primarily based on the HLB value method, with octadecyltrimethylammonium chloride and hexadecyltrimethylammonium chloride being weakly alkaline, particularly suitable for degrading severely acidified waterlogged wooden artifacts with low pH values. The role of co-surfactants is to regulate the stability and viscosity of the emulsion. Isopropanol, ethanol, or polyethylene glycol (PEG-200) can make the emulsion more uniform and stable. Combining them with 1-hexanol, p-nonylphenol, or polyethylene glycol monobutyl ether to reduce viscosity can improve the emulsion's permeability in the wood.

[0047] Furthermore, in the silicone emulsion, the mass fraction of silicone monomer is 20% to 50%, the mass fraction of surfactant is 10% to 30%, and the mass fraction of co-surfactant is 3% to 10%.

[0048] To ensure the effective coating of wood cell walls after in-situ polymerization of organosilicon, the mass fraction of organosilicon monomer should not exceed 20% for saturated wood artifacts with a moisture content below 300%; and should be higher than 30% for saturated wood artifacts with a moisture content above 500%. The amount of surfactant added should be minimized while ensuring emulsion stability, and the total mass fraction of surfactant and co-surfactant should not exceed 30%.

[0049] Further, the specific operational steps of steps (2) to (3) are as follows: The organosilicon monomer is thoroughly mixed with the surfactant and co-surfactant, then pure water is added, and the mixture is dispersed evenly by mechanical stirring or ultrasonic oscillation to prepare an organosilicon emulsion with an effective ingredient content of 20wt% to 50wt%. A few drops of the emulsion are added to water, and the emulsion is confirmed to be an O / W type emulsion by dilution. If no demulsification or stratification occurs after standing for 24 hours, it indicates that the organosilicon emulsion system is relatively stable.

[0050] The present invention also provides an organosilicon emulsion prepared by the above method.

[0051] The present invention also provides a method for dehydrating and shaping waterlogged wooden artifacts using the above-mentioned organosilicon emulsion, comprising the following processing steps:

[0052] (1) Emulsion penetration step: Immerse the water-saturated wooden artifact in the silicone emulsion until the weight of the artifact is constant.

[0053] (2) Catalytic initiation step: Add an appropriate amount of catalyst to the organosilicon emulsion to initiate the polymerization reaction of organosilicon in the water-saturated wooden artifacts.

[0054] (3) Polymerization and drying steps: After the viscosity of the silicone emulsion increases significantly (above 200 mPa·S), the wooden artifacts are removed from the silicone emulsion, the residual emulsion on the surface is removed, and the water-saturated wooden artifacts are allowed to dry naturally or slowly under controlled conditions.

[0055] Furthermore, the specific operation methods of emulsion penetration in step (1) include immersion, spraying, injection, and drip infiltration, which can be flexibly selected or multiple processes can be used in combination depending on the size and preservation condition of the waterlogged wooden artifact. Immersion method can be given priority for movable small artifacts and artifacts with a high degree of degradation, while spraying method can be used for large and immovable artifacts. For large artifacts and artifacts with uneven degradation, injection and drip infiltration methods can be used.

[0056] Furthermore, the specific steps for emulsion penetration in step (1) are as follows: place the water-saturated wooden artifact in a container with a volume at least four times that of the artifact, ensuring it is completely immersed in the prepared emulsion, with a liquid-to-solid ratio of approximately 1:1 to 4:1. The immersion time for small wooden artifacts with a thickness of 1-3 cm is approximately 3-15 days, while the immersion time for artifacts with a thickness of 5 cm or more, or those with an extremely high degree of degradation (water content > 600%), needs to be extended to more than 20 days.

[0057] Further, the specific operational steps of the spraying method in step (1) are as follows: using a manual sprayer or automatic spraying equipment, the prepared emulsion is evenly sprayed onto the surface of the wooden artifact, ensuring the surface is completely wetted and has flowing liquid. During the process, the artifact's condition needs to be observed regularly, and spraying should be replenished promptly before the surface dries. When the ambient humidity is higher than 80%, spraying is required every 24 hours; when the ambient humidity is lower, the spraying cycle can be shortened to 3-8 hours. The spraying time can be selected according to the total volume of the artifact. Generally, the total spraying time for small and medium-sized artifacts is 3-15 days, while large artifacts over 1 meter in size require 10-20 days or more of spraying. Adjustments can be made flexibly according to the size of the artifact and the ambient humidity.

[0058] Furthermore, the specific steps of the injection method in step (1) are as follows: on the basis of soaking or spraying, injection points are evenly distributed on the water-saturated wooden artifact, and the emulsion is injected into the artifact with a syringe, or injection is performed on the local parts of the artifact that require special reinforcement.

[0059] Furthermore, the specific operation steps of the infiltration method using the drip bottle in step (1) are as follows: evenly distribute infusion points on the cultural relic, fill the bottle with the emulsion, hang it at a high place, and drive the emulsion into the interior of the cultural relic through micro-pressure.

[0060] Furthermore, the catalyst selected in step (2) is one of the following materials: dibutyltin dilaurate, triethylenetetramine, octylamine, and (3-aminopropyl)triethoxysilane, in an amount of approximately 0.5% to 2%.

[0061] Here, octylamine and (3-aminopropyl)triethoxysilane have high catalytic efficiency, enabling the organosilicon emulsion to rapidly polymerize and solidify, which is beneficial to improving the dehydration efficiency of waterlogged wooden artifacts; triethylenetetramine and dibutyltin dilaurate have moderate catalytic efficiency, resulting in lower wood cell cavity filling rate and smaller weight gain after polymerization, making them suitable for more fragile artifacts.

[0062] Further, the specific operation method of step (2) is as follows: after the organosilicon emulsion has fully penetrated into the wood, that is, after the weight of the wooden artifact is constant, an appropriate amount of catalyst is added to the organosilicon emulsion and stirred evenly to initiate a polymerization reaction. The penetration continues for 3 to 15 days to allow the catalyst to fully contact the organosilicon in the wood. The organosilicon emulsion is sampled and tested regularly, and the reaction progress is judged by the viscosity of the emulsion. When the viscosity of the residual organosilicon emulsion on the surface of the water-saturated wooden artifact increases significantly, the soaking should be stopped in time, and the artifact should be taken out for cleaning and drying.

[0063] Furthermore, in step (3), the method for removing residual emulsion involves spraying with pure water and gently brushing or wiping to ensure that there is no polymer buildup on the surface of the water-saturated wooden artifact, so as not to affect its appearance.

[0064] Furthermore, step (3) is specifically performed by natural drying or slow drying under controlled humidity conditions. During natural drying, the relative humidity should not be lower than 30%, and water can be sprayed appropriately if the humidity is too low. Slow drying under controlled humidity conditions can be achieved by wrapping the object in plastic film and then puncturing it before slow drying, slow drying in a high-humidity environment, or drying in a constant temperature and humidity chamber. Drying is considered complete when the weight and surface hardness of the wooden artifact remain essentially constant.

[0065] like Figure 1 As shown, the method for dehydrating and shaping waterlogged wooden artifacts provided by the technical solution of the present invention includes:

[0066] Step 101: Mix the organosilicon monomer, surfactant, co-surfactant and pure water in an appropriate ratio and disperse them thoroughly to form a stable oil-in-water emulsion;

[0067] Step 102: Allow the silicone emulsion to fully penetrate the waterlogged wooden artifact, partially replacing the original moisture in the artifact, until the weight is constant;

[0068] Step 103: Add an appropriate amount of catalyst to the silicone emulsion, and then allow it to penetrate for a short time to allow the silicone in the water-saturated wooden artifact to begin a polymerization reaction.

[0069] Step 104: Stop applying the silicone emulsion, remove any residual emulsion from the surface, and allow the saturated wooden artifact to air dry naturally or slowly until the polymerization reaction is complete.

[0070] Example 1

[0071] The dehydration and shaping object was a water-saturated archaeological wood sample taken from the "Nanhai No. 1" shipwreck. The maximum moisture content was about 480%, and it was in a heavily degraded state. The size was about 1cm×1cm×1.5cm (thickness).

[0072] (1) Soak and clean the waterlogged archaeological wood thoroughly in pure water to remove the soluble salts and silt inside.

[0073] (2) The emulsion used in this embodiment contains 30 wt% bis(triethoxysiloxane), 10 wt% (3-aminopropyl)triethoxysilane, and 20 wt% ethanol.

[0074] (3) Mix bis(triethoxysiloxane), (3-aminopropyl)triethoxysilane and ethanol thoroughly by mechanical vibration to prepare 5 ml of organosilicon emulsion. Immerse the waterlogged archaeological wood sample completely in the organosilicon emulsion. After 3 days, remove the sample, rinse the emulsion off the surface of the sample, and let it air dry in a laboratory environment.

[0075] (4) After dehydration and shaping treatment, the waterlogged archaeological wood sample became darker in color than before dehydration, turning into a dark brown wood color with a slight varnish luster on the surface. There was no obvious shrinkage or deformation; the volume shrinkage rate was measured to be 4.60% by the water displacement method.

[0076] Example 2

[0077] The dehydration and shaping object was a waterlogged wooden ship plank fragment taken from the "Nanhai No. 1" shipwreck. The maximum moisture content was about 520%, and it was in a heavily degraded state. The size was about 10.1cm × 5.5cm × 1.3cm (thickness).

[0078] (1) Soak the waterlogged archaeological wood thoroughly in pure water to clean the surface silt and attachments, and remove the soluble salts and silt inside.

[0079] (2) The emulsion used in this embodiment contains 30 wt% bis(triethoxysilane), 10 wt% octadecyltrimethylammonium chloride, and 10 wt% polyethylene glycol monobutyl ether.

[0080] (3) The organosilicon dispersion was prepared by mechanically mixing bis(triethoxysilane), octadecyltrimethylammonium chloride and polyethylene glycol monobutyl ether. The dispersion was then slowly added to pure water and mechanically stirred at 100 r / min for 20 min to prepare 120 ml of organosilicon emulsion.

[0081] (4) The saturated ship plate fragments were completely immersed in the silicone emulsion for 14 days. Then, 0.6 g of dibutyltin dilaurate was added to the emulsion and stirred evenly. After immersion for another 10 days, when the viscosity of the emulsion increased to about 100 mPa·s, the ship plate fragments were removed. The emulsion and accumulated polymer on the surface were brushed off and placed in a humid environment with a relative humidity of about 85% for several days to dry slowly. Finally, they were transferred to a laboratory environment to dry naturally.

[0082] (5) After dehydration and shaping treatment, the color of the waterlogged ship plank fragment sample was slightly darker than before dehydration, exhibiting a natural wood color, with some areas of the surface showing a slight varnish sheen (e.g., Figure 2 (As shown in a and b). After treatment, the ship plank fragment showed no significant shrinkage or deformation; the volume shrinkage rate measured by the displacement method was 2.50%, and the wood weight gain was only 133%. Scanning electron micrographs and EDS energy dispersive spectroscopy analysis results (e.g., ...) Figure 3 As shown in the figure, organosilicon is directionally distributed on the wood cell walls, not filling the cell pores, but providing good support for the cell wall structure, and the cells did not deform or collapse. Water vapor adsorption-desorption test (as shown in the figure) Figure 4 As shown in the figure, the equilibrium moisture absorption rate of wood treated with silicone emulsion at 95% RH is only 8.1%, which is significantly reduced by about 60% compared with the blank sample and only 10% of that of the sample treated with traditional dehydration material (PEG). This indicates that the silicone emulsion dehydration material significantly improves the moisture resistance of wooden artifacts and is beneficial for long-term storage.

[0083] Example 3

[0084] The dehydration and shaping material was a waterlogged wood block taken from the "Nanhai No. 1" shipwreck. The maximum moisture content was about 320%, and it was in a moderate degradation state. The surface was severely soft and rotten in some areas (moisture content of about 400% or more). The size was about 4.5cm × 6.5cm × 2.0cm (thickness).

[0085] (1) Soak the waterlogged wood blocks in pure water to thoroughly clean them, scrub off the surface mud and attached substances, and remove the soluble salts and mud inside.

[0086] (2) The emulsion used in this embodiment contains 15 wt% dodecyltrimethoxysilane, 10% polydimethylsiloxane, 15% fatty alcohol polyoxyethylene ether phosphate and 10 wt% isopropanol.

[0087] (3) Add isopropanol to dodecyltrimethoxysilane and polydimethylsiloxane, mix thoroughly by mechanical vibration, then mix in fatty alcohol polyoxyethylene ether phosphate to make an organosilicon dispersion, slowly add the dispersion to pure water, ultrasonically vibrate for 20 minutes, mix thoroughly to make 50ml organosilicon emulsion.

[0088] (4) Place the saturated wood block in a semi-closed environment with a relative humidity of about 85%. Spray the saturated wood block with emulsion once every 12 hours, with a spray volume of about 2 ml / time, so that the emulsion evenly wets the wood block, and perform dehydration treatment for 10 days. Then add 0.8 g of octylamine to the remaining emulsion in the spray bottle and shake well. Continue spraying for 3 days, then take out the wood block, brush off the emulsion and accumulated polymer on its surface, place it in a perforated sealed bag and dry slowly for several days, and then transfer it to a laboratory environment to dry naturally.

[0089] (5) After dehydration and shaping treatment, the color of the saturated wood block became lighter than before dehydration, turning into a light yellowish wood color, with a natural, matte surface texture. After treatment, the wood block showed no obvious shrinkage or deformation, and the surface hardness increased by about 50%. The measured three-dimensional shrinkage rates were 1.5%, 2.2%, and 0.4%, respectively, and the wood weight gain rate was 210%.

[0090] Example 4

[0091] The dehydration and shaping material was taken from waterlogged wood from the "Nanhai No. 1" shipwreck. The overall average maximum moisture content was over 820%, and the wood was in a state of severe degradation. The surface was severely soft and rotten in some areas, and the wood was irregularly elliptical in shape, with a size of about 4cm×7cm×21cm.

[0092] (1) Soak the waterlogged wood blocks in pure water to thoroughly clean them, scrub off the surface mud and attached substances, and remove the soluble salts and mud inside.

[0093] (2) The emulsion used in this embodiment contains 20 wt% bis(triethoxysilane), 20 wt% hydroxyl-terminated polydimethylsiloxane, 12 wt% fatty alcohol polyoxyethylene ether phosphate, 8 wt% triphenylethylphenol polyoxyethylene ether and 5 wt% low molecular weight polyethylene glycol.

[0094] (3) Add bis(triethoxysilane) to fatty alcohol polyoxyethylene ether phosphate, and mix hydroxyl-terminated polydimethylsiloxane with triphenylethylphenol polyoxyethylene ether. Mix the two solutions and thoroughly mix them by mechanical vibration. Then mix in polyethylene glycol to prepare an organosilicon dispersion. Slowly add the dispersion to pure water and mechanically stir for 1 hour to prepare a 2L organosilicon emulsion.

[0095] (4) Immerse saturated wood in silicone emulsion, and set injection points at both ends. Use a drip infusion method to allow the silicone solution to penetrate into the wood core. After dehydration for 30 days, mix 1% dibutyltin dilaurate into the silicone emulsion and stir well. Take a portion of the emulsion and load it into a syringe. Inject the emulsion and catalyst into the wood core along the injection points every other day. Continue infusion for 15 days, then remove the wood block, brush off the emulsion and accumulated polymer on its surface, and place it in a semi-open environment of about 85% RH for slow drying for several days. Then, transfer it to a laboratory environment for natural drying.

[0096] (5) After dehydration and shaping treatment, the color of the saturated wood becomes lighter than before dehydration, turning into a light brown wood color, with a natural, matte surface texture. After treatment, the ship plank fragments showed no obvious shrinkage, deformation, or twisting, and the surface hardness increased by about 70%. The weight gain of the wood after drying was 165%.

[0097] In summary, this invention discloses an organosilicon emulsion, its preparation method, and its application in the dehydration and shaping of waterlogged wooden artifacts. This invention uses a surfactant to encapsulate organosilicon monomers, forming an O / W emulsion that directly penetrates the interior of the waterlogged wooden artifact. This eliminates the need for pre-dehydration of the artifact, avoiding the use of large amounts of organic reagents and significantly shortening the dehydration and shaping time. It is environmentally friendly and highly efficient. The polymerization rate is controllable, and the generated organosilicon polymer adheres directionally to the wood cell walls, providing support and reinforcement without excessively filling the cell cavities, leaving space for future reprocessing and conforming to the principle of reprocessable artifact preservation.

[0098] The above embodiments and descriptions are merely the principles and preferred embodiments of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope thereof, and all such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A method for dehydrating and shaping waterlogged wooden artifacts using organosilicon emulsion, characterized in that, Includes the following steps: (1) Emulsion penetration step: Immerse the water-saturated wooden artifact in the silicone emulsion until the weight of the water-saturated wooden artifact is constant; (2) Catalytic initiation step: Add an appropriate amount of catalyst to the organosilicon emulsion to initiate the polymerization reaction of the organosilicon emulsion; (3) Polymerization and drying step: After the viscosity of the silicone emulsion increases, the water-saturated wooden artifact is taken out of the silicone emulsion, the residual emulsion on the surface is removed, and the water-saturated wooden artifact is dried, thereby completing the dehydration and shaping of the water-saturated wooden artifact; The method for preparing the organosilicon emulsion includes the following steps: (1) Take 2-5 parts of organosilicon monomer, 1-3 parts of surfactant, 0.3-1 parts of co-surfactant, and 3-6 parts of pure water for later use; (2) Add surfactant and co-surfactant to the organosilicon monomer, and stir or shake continuously until uniform to form a transparent organosilicon dispersion; (3) Pour the organosilicon dispersion into pure water and stir or shake thoroughly to form a stable organosilicon emulsion.

2. The method according to claim 1, characterized in that, The organosilicon monomer is one or more of the following materials: dodecyltrimethoxysilane, bistriethoxysilane, and bistriethoxysiloxane.

3. The method according to claim 1, characterized in that, The surfactant is one or more of the following materials: fatty acid polyoxyethylene ester, triphenylethylphenol polyoxyethylene ether, polyoxyethylene hydrogenated castor oil, fatty alcohol polyoxyethylene ether phosphate, alkylphenol polyoxyethylene ether, octadecyltrimethylammonium chloride, and hexadecyltrimethylammonium chloride.

4. The method according to claim 1, characterized in that, The co-surfactant is one or more of the following materials: ethanol, isopropanol, polyethylene glycol, 1-hexanol, p-nonylphenol, and polyethylene glycol monobutyl ether.

5. The method according to claim 1, characterized in that, The organosilicon monomer has a mass fraction of 20% to 50%, the surfactant has a mass fraction of 10% to 30%, and the co-surfactant has a mass fraction of 3% to 10%.

6. The method according to claim 1, characterized in that, In step (1) of the method for dehydrating and shaping waterlogged wooden artifacts, the amount of organosilicon emulsion used is 1 to 4 times the volume of the waterlogged wooden artifact being treated, and is adjusted according to the maximum water content of the waterlogged wooden artifact.

7. The method according to claim 1, characterized in that, The catalyst used in step (2) of the method for dehydrating and shaping waterlogged wooden artifacts is one of the following materials: dibutyltin dilaurate, triethylenetetramine, octylamine and (3-aminopropyl)triethoxysilane.

8. The method according to claim 7, characterized in that, In step (2) of the method for dehydrating and shaping waterlogged wooden artifacts, the amount of catalyst used is 0.5% to 2%.

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