Artificial board emulsifying wax as well as preparation method and application thereof

Abstract

The invention discloses artificial board emulsifying wax, which is prepared from the following raw materials in percentage by mass: 25 to 40 percent of paraffin, 3 to 5 percent of compound emulsifier, 2 to 4 percent of cationic starch, 3 to 7 percent of liquid polybutadiene and 44 to 67 percent of water, the compound emulsifier is a nonionic emulsifier, and the hydrophilic-lipophilic balance value is 9-10. The artificial board emulsifying wax is good in waterproofness and high in strength when applied to artificial boards.

Description

Technical Field

[0001] This invention relates to the chemical industry, specifically to an emulsified wax for engineered wood panels, its preparation method, and its application. Background Technology

[0002] Water resistance is one of the main performance indicators of engineered wood products. The traditional engineered wood product industry mainly uses solid paraffin or molten paraffin as a waterproofing additive. Its waterproofing principle is a physical phenomenon that blocks the gaps between fibers. However, because solid paraffin or molten paraffin particles are large and cannot be evenly coated on the surface of engineered wood products, the strength of engineered wood products decreases, making them prone to cracking and deformation, while the waterproofing performance also decreases.

[0003] Therefore, people began using emulsified wax as a waterproofing agent for engineered wood products. Taking advantage of the small particle size of emulsified wax, the wax particles are effectively demulsified during the engineered wood product manufacturing process, allowing them to precipitate and adhere more evenly to the board. However, the waterproofing effect of existing emulsified waxes as engineered wood product waterproofing agents is not ideal. Although paraffin wax is hydrophobic, it is difficult for emulsified wax to achieve waterproofing on the coated surface after application and drying at room temperature. This is because the coating surface consists of dispersed paraffin wax particles distributed on the board, and the gaps between the paraffin wax particles allow water to pass through.

[0004] To address this issue, researchers attempted to fuse these discretely arranged wax particles together by heating to form a continuous film. However, this did not significantly improve the water resistance of the coating surface because the continuous film remained discrete under a microscope. This discrepancy is likely due to the presence of pores, fractures, or gaps in the crystals, which develop due to the crystallinity and brittleness of hydrocarbon waxes and allow water penetration. In addition, researchers tried using additives to lower the film-forming temperature of the hydrocarbon waxes, but these additives themselves did not exhibit ideal water resistance or compatibility with the hydrocarbon waxes.

[0005] Chinese patent document CN101597482A discloses an emulsified paraffin waterproofing agent for medium-density fiberboard (MDF). This emulsified paraffin waterproofing agent is prepared by emulsifying solid paraffin using sodium dodecyl sulfate, Span-60, and monoglycerides as emulsifiers, Powdered O (fatty alcohol polyoxyethylene ether) and Tween-80 as catalysts, and polyvinyl alcohol as a colloidal protectant. However, the presence of highly hydrophilic surfactants such as sodium dodecyl sulfate in this emulsified paraffin in the fiberboard can severely affect its waterproofing performance.

[0006] Therefore, developing a wood-based panel emulsion wax to improve the water resistance and strength of wood-based panels is a pressing technical problem that needs to be solved. Summary of the Invention

[0007] In view of this, the present invention provides an emulsified wax for engineered wood products, its preparation method and application, to overcome the defects of existing emulsified waxes for engineered wood products, such as poor water resistance and low strength.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An emulsified wax for engineered wood panels comprises, by weight percentage: 25%–40% paraffin wax, 3%–5% composite emulsifier, 2%–4% cationic starch, 3%–7% liquid polybutadiene, and 44%–67% water;

[0010] The composite emulsifier is a nonionic emulsifier with a hydrophilic-lipophilic balance (HLB) value of 9 to 10.

[0011] The artificial board emulsified wax provided by this invention, when used in artificial boards, can uniformly compensate for the discontinuous film formation on the fiber surface of the artificial board caused by the crystallization of paraffin itself due to the low-temperature fluidity and waterproof properties of liquid polybutadiene, while significantly improving the internal bonding strength of the artificial board.

[0012] In one optional embodiment, the artificial board emulsified wax comprises, by weight percentage, the following raw materials: 30%–35% paraffin wax, 3.5%–4.5% composite emulsifier, 3%–3.5% cationic starch, 5%–6% liquid polybutadiene, and 51%–58.5% water.

[0013] In one optional embodiment, the cationic starch is selected from quaternary ammonium salt cationic starch or etherified cationic starch. Preferably, the etherified cationic starch is selected from tertiary ammonium alkyl ether starch or quaternary ammonium alkyl ether starch.

[0014] In one optional embodiment, the cationic starch comprises both amylose and amylopectin. Amylose is more soluble in water and can form a more stable continuous phase by interacting with water molecules. The dissolution of amylopectin increases the viscosity of the emulsion, thereby reducing Brownian motion of droplets, decreasing the probability of collisions between droplets, and improving the chemical and mechanical stability of the emulsion. Furthermore, the cations in the cationic starch adhere to the dispersed phase, increasing the repulsive force between the dispersed phase and significantly improving the stability of the emulsion wax compared to non-cationic starch.

[0015] Meanwhile, the entanglement of cationic starch and liquid polybutadiene at the oil-water interface, along with the synergistic effect of the composite emulsifier, significantly enhances the stability of the emulsified wax. Through the synergistic effect of the three additives, the mutual contact between the paraffin particles dispersed phase is blocked while reducing the amount of emulsifier, thus improving the stability of the emulsified wax.

[0016] In one optional embodiment, the number-average molecular weight of the liquid polybutadiene is 500 to 8000, preferably 800 to 5000. Liquid polybutadiene with a number-average molecular weight below 500 results in a weak waterproof layer, while liquid polybutadiene with a number-average molecular weight exceeding 8000 makes it difficult for paraffin to emulsify in water.

[0017] In one alternative embodiment, the composite emulsifier is selected from any two of Tween 80, Tween 60, Span 80, and Span 60.

[0018] Because paraffin molecules have weak cohesive forces and low surface tension in emulsified waxes, they easily aggregate into large particles. To mix paraffin with water to form a stable O / W emulsified wax, the emulsifier molecule must contain groups with a similar structure to paraffin to achieve affinity and obtain a stable emulsion. The composite emulsifier described in this invention is a nonionic emulsifier, for example, a blend of two of Tween 80, Tween 60, Span 80, and Span 60. By adjusting the blending ratio, the hydrophilic-lipophilic balance (HLB) value of the composite emulsifier is similar to that of paraffin, approximately 9-10. According to the principle of "like dissolves like," paraffin can be more fully dispersed in water to form an O / W emulsion. This composite emulsifier contains both lipophilic and hydrophilic emulsifiers, which interact to effectively reduce the interfacial tension between paraffin and water, resulting in a microemulsion with good film-forming properties and less prone to demulsification.

[0019] In one optional embodiment, the cationic starch is selected from either quaternary ammonium salt cationic starch or etherified cationic starch.

[0020] In one alternative embodiment, the paraffin wax is selected from fully refined paraffin wax and / or semi-refined paraffin wax, preferably semi-refined paraffin wax. Examples include No. 54 fully refined paraffin wax and No. 58 semi-refined paraffin wax.

[0021] The present invention also provides a method for preparing the above-mentioned artificial board emulsion wax, comprising the following steps:

[0022] Paraffin wax and liquid polybutadiene are mixed and heated until the paraffin wax is completely melted. Then, a composite emulsifier, cationic starch, and boiling water are added and mixed. The mixture is then cooled to 60-75°C and homogenized into an emulsion to obtain artificial board emulsion wax.

[0023] In one optional embodiment, the heating temperature is 80–90°C, and the mixing time is 5–15 min.

[0024] This invention also provides a method for preparing a wood-based panel, comprising the following steps:

[0025] Wood pulp is mixed with adhesives and emulsified wax to obtain a mixture, which is then sequentially laid, pre-pressed, and hot-pressed to obtain engineered wood panels.

[0026] The emulsified wax is selected from the above-mentioned artificial board emulsified wax or the artificial board emulsified wax prepared by the above-mentioned artificial board emulsified wax preparation method.

[0027] Preferably, the adhesive is selected from urea-formaldehyde resin.

[0028] In one optional embodiment, a fiberboard blank is obtained by laying, and then the fiberboard blank is pre-pressed and hot-pressed. The specific implementation of the laying process is not particularly required; conventional methods can be used. The parameters for pre-pressing and hot-pressing can be conventional and can be adjusted according to actual needs. For example, pre-pressing can be performed at 20–90℃ and 0.5–2 MPa, and hot-pressing can be performed at 180–240℃ and 1.7–4.5 MPa.

[0029] The present invention also provides an artificial board prepared by the above-mentioned method, wherein the amount of emulsified wax in each cubic meter of artificial board is 4-8 kg and the amount of adhesive is 70-90 kg.

[0030] Compared with the prior art, the present invention has at least the following beneficial effects:

[0031] Beneficial effect 1: The artificial board emulsion wax provided by the present invention, through the mutual cooperation between the components, forms a basically transparent, smooth, highly adhesive, and waterproof film during the preparation of artificial boards, which greatly improves the waterproof performance and strength of artificial boards.

[0032] Beneficial Effect 2: The artificial board emulsified wax provided by this invention can reduce the amount of emulsifier by introducing cationic starch. The amount of emulsifier is only 3% to 5% of that in the artificial board emulsified wax. Cationic starch can increase the electrostatic repulsion of the dispersed phase and improve the stability of the artificial board emulsified wax. At the same time, the interaction between starch and liquid polybutadiene further increases the mechanical strength and thickness of the oil-water interface film. The synergistic effect between starch, liquid polybutadiene, and the composite emulsifier can significantly enhance the stability of the artificial board emulsified wax. The interaction between liquid polybutadiene and emulsified wax can form a continuous film on the surface of the artificial board fibers, which can make up for the defect of poor water resistance caused by the crystallization of paraffin itself. Adding it to the preparation of artificial boards can significantly improve the water resistance, stability, and internal bonding strength of the boards, and reduce the production cost of the boards. Detailed Implementation

[0033] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0034] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0035] Commercially available raw materials can meet the requirements for implementing the technical solution of this invention. The raw materials involved in the following embodiments and comparative examples all come from the following sources:

[0036] Evaluation and analysis methods:

[0037] Centrifugal stability: The centrifugal stability of the emulsion was determined according to GB11543-2008. The emulsion was centrifuged at 4000 r / min for 15 min and observed to see if it separated into layers.

[0038] Storage stability: After the sample is sealed and stored at room temperature for a period of time, observe whether it separates into layers.

[0039] Raw material source:

[0040] No. 58 semi-refined paraffin wax, Daqing Petrochemical Company of China National Petroleum Corporation;

[0041] No. 54 fully refined paraffin wax, China Petroleum Fushun Petrochemical;

[0042] Quaternary ammonium salt cationic starch (DM933 cationic starch), Dongguan Dongmei Food Co., Ltd.;

[0043] Etherified cationic starch (CQ651844), Anhui Cool Biotechnology;

[0044] Cationic cellulose (JR400), Dow Chemical, USA;

[0045] Ordinary starch, Beidahuang Group;

[0046] Liquid polydibutylene, Tween 80, Tween 60, Span 80, Span 60, Sinopharm Chemical Reagent Co., Ltd.;

[0047] Polyacrylic acid (molecular weight 3000-5000), Tianjin Kemio Chemical Reagent.

[0048] Example 1

[0049] This embodiment provides an emulsified wax for engineered wood panels, the preparation method of which includes the following steps:

[0050] Under stirring, 25g of paraffin wax (No. 58 semi-refined paraffin wax) and 3g of liquid polybutadiene (number average molecular weight 8000) were mixed and heated to 80°C to completely melt the paraffin wax. Then, 3g of emulsifier (Span 60:Tween 60 = 57.9:42.1 (mass ratio), HLB = 9.0) and 2g of quaternary ammonium cationic starch were added, along with 67g of boiling water. The mixture was stirred for approximately 5 minutes and then cooled to 60°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (3000 rpm for 10 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0051] Example 2

[0052] This embodiment provides an emulsified wax for engineered wood panels, the preparation method of which includes the following steps:

[0053] Under stirring, 32g of paraffin wax (No. 58 semi-refined paraffin wax) and 5g of liquid polybutadiene (number average molecular weight 4000) were mixed and heated to 85°C to completely melt the paraffin wax. Then, 4g of emulsifier (Span 80:Tween 80 = 51.4:48.6, HLB = 9.5 (mass ratio)) and 3g of quaternary ammonium cationic starch were added, along with 56g of boiling water. The mixture was stirred for approximately 10 minutes and then cooled to 65°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (5000 rpm for 15 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0054] Example 3

[0055] This embodiment provides an emulsified wax for engineered wood panels, the preparation method of which includes the following steps:

[0056] Under stirring, 40g of paraffin wax (No. 58 semi-refined paraffin wax) and 7g of liquid polybutadiene (number average molecular weight 500) were mixed and heated to 90°C to completely melt the paraffin wax. Then, 5g of emulsifier (Span 80: Tween 60 = 46.3:53.7, HLB = 10, (mass ratio)) and 4g of etherified cationic starch were added, along with 44g of boiling water. The mixture was stirred for approximately 15 minutes and then cooled to 75°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (8000 rpm for 20 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0057] Example 4

[0058] This embodiment provides an emulsified wax for engineered wood panels, the preparation method of which includes the following steps:

[0059] Under stirring, 33g of paraffin wax (No. 54 fully refined paraffin wax) and 5.5g of liquid polybutadiene (number average molecular weight 3000) were mixed and heated to 87°C to completely melt the paraffin wax. At this point, 3g of emulsifier (Span 80: Tween 80 = 51.4:48.6, HLB = 9.5, (mass ratio)) and 4g of etherified cationic starch were added, along with 54.5g of boiling water. The mixture was mixed for about 8 minutes and then cooled to 70°C. Finally, at this temperature, the mixture was processed into a homogenized emulsion using a homogenizer (5000 rpm for 13 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0060] Example 5

[0061] This embodiment provides an emulsified wax for engineered wood panels, the preparation method of which includes the following steps:

[0062] Under stirring, 38g of paraffin wax (No. 54 fully refined paraffin wax) and 5g of liquid polybutadiene (number average molecular weight 3000) were mixed and heated to 80°C to completely melt the paraffin wax. Then, 4g of emulsifier (Span 80: Tween 60 = 51.4:48.6, HLB = 9.5, (mass ratio)) and 2g of etherified cationic starch were added, along with 51g of boiling water. The mixture was stirred for approximately 10 minutes and then cooled to 70°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (6000 rpm for 20 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0063] Comparative Example 1

[0064] This comparative example is similar to Example 2, except that liquid polybutadiene and cationic starch were not added, and the amounts of emulsifier and boiling water are different. The preparation method of the artificial board emulsion wax provided in this comparative example includes the following steps:

[0065] While stirring, 32g of paraffin wax (No. 58 semi-refined paraffin wax) was heated to 85°C until completely melted. Then, 10g of emulsifier (Span 80: Tween 80 = 51.4:48.6, HLB = 9.5, (mass ratio)) and 58g of boiling water were added. The mixture was mixed for approximately 10 minutes, then cooled to 65°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (5000 rpm for 15 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the emulsified wax for engineered wood panels.

[0066] Comparative Example 2

[0067] This comparative example is similar to Example 1, except that liquid polybutadiene was not added and the amount of boiling water used is different. The preparation method of the artificial board emulsion wax provided in this comparative example includes the following steps:

[0068] While stirring, 25g of paraffin wax (No. 58 semi-refined paraffin wax) was heated to 80°C until completely melted. Then, 3g of emulsifier (Span 60: Tween 60 = 57.9:42.1, HLB = 9.0 (mass ratio)) and 2g of quaternary ammonium cationic starch were added, along with 70g of boiling water. The mixture was stirred for approximately 5 minutes and then cooled to 60°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (3000 rpm for 10 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0069] Comparative Example 3

[0070] This comparative example is similar to Example 3, except that cationic starch was not added and the amount of boiling water used is different. The preparation method of the artificial board emulsion wax provided in this comparative example includes the following steps:

[0071] Under stirring, 40g of paraffin wax (No. 58 semi-refined paraffin wax) and 7g of liquid polybutadiene (number average molecular weight 500) were mixed and heated to 90°C to completely melt the paraffin wax. At this point, 5g of emulsifier (Span 80: Tween 60 = 46.3:53.7, HLB = 10, (mass ratio)) and 48g of boiling water were added. The mixture was mixed for about 15 minutes and then cooled to 75°C. Finally, at this temperature, the mixture was processed into a homogenized emulsion using a homogenizer (8000 rpm for 20 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0072] Comparative Example 4

[0073] This comparative example is similar to Example 4, except that cationic cellulose is used instead of cationic starch. The preparation method of the artificial board emulsion wax provided in this comparative example includes the following steps:

[0074] Under stirring, 33g of paraffin wax (No. 54 fully refined paraffin wax) and 5.5g of liquid polybutadiene (number average molecular weight 3000) were mixed and heated to 87°C to completely melt the paraffin wax. At this point, 3g of emulsifier (Span 80: Tween 80 = 51.4:48.6, HLB = 9.5, (mass ratio)) and 4g of cationic cellulose were added, along with 54.5g of boiling water. The mixture was mixed for about 8 minutes and then cooled to 70°C. Finally, at this temperature, the mixture was processed into a homogenized emulsion using a homogenizer (5000 rpm for 13 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the emulsified wax for engineered wood panels.

[0075] Comparative Example 5

[0076] This comparative example is similar to Example 2, except that ordinary unmodified starch is used instead of cationic starch in this comparative example. The preparation method of the artificial board emulsion wax provided in this comparative example includes the following steps:

[0077] Under stirring, 32g of paraffin wax (No. 58 semi-refined paraffin wax) and 5g of liquid polybutadiene (number average molecular weight 4000) were mixed and heated to 85°C to completely melt the paraffin wax. Then, 4g of emulsifier (Span 80:Tween 80 = 51.4:48.6, HLB = 9.5 (mass ratio)) and 3g of ordinary starch were added, along with 56g of boiling water. The mixture was stirred for approximately 10 minutes and then cooled to 65°C. Finally, at this temperature, the mixture was homogenized into a homogenized emulsion using a homogenizer (5000 rpm for 15 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0078] Comparative Example 6

[0079] Comparative Example 6 is similar to Example 4, except that the emulsifier ratio is different. The preparation method of the artificial board emulsified wax provided in this comparative example includes the following steps:

[0080] Under stirring, 33g of paraffin wax (No. 54 fully refined paraffin wax) and 5.5g of liquid polybutadiene (number average molecular weight 3000) were mixed and heated to 87°C to completely melt the paraffin wax. At this point, 3g of emulsifier (Span 80: Tween 80 = 65.4:35.6, HLB = 8, (mass ratio)) and 4g of etherified cationic starch were added, along with 54.5g of boiling water. The mixture was mixed for about 8 minutes and then cooled to 70°C. Finally, at this temperature, the mixture was processed into a homogenized emulsion using a homogenizer (5000 rpm for 13 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0081] Comparative Example 7

[0082] Comparative Example 7 is similar to Example 5, except that liquid polyacrylic acid is used instead of liquid polybutadiene. The preparation method of the artificial board emulsion wax provided in this comparative example includes the following steps:

[0083] Under stirring, 38g of paraffin wax (No. 54 fully refined paraffin wax) and 5g of liquid polyacrylic acid were mixed and heated to 80°C to completely melt the paraffin wax. At this point, 4g of emulsifier (Span 80: Tween 60 = 51.4:48.6, HLB = 9.5, (mass ratio)) and 2g of etherified cationic starch were added, along with 51g of boiling water. The mixture was mixed for about 10 minutes and then cooled to 70°C. Finally, at this temperature, the mixture was processed into a homogenized emulsion using a homogenizer (6000 rpm for 20 minutes). This homogenized emulsion was then slowly cooled to room temperature to obtain the artificial board emulsion wax.

[0084] Experimental Example 1

[0085] The stability of the artificial board emulsion waxes prepared in the above embodiments and comparative examples was tested according to the above evaluation method. The specific results are shown in Table 1 below.

[0086] Table 1 Properties of Emulsified Wax Products for Wood-based Panels

[0087] Appearance Centrifugal stability Static stability Example 1 Milky white, fine and even Centrifugation without stratification 20 months Example 2 Milky white, fine and even Centrifugation without stratification 24 months Example 3 Milky white, fine and even Centrifugation without stratification 20 months Example 4 Milky white, fine and even Centrifugation without stratification 22 months Example 5 Milky white, fine and even Centrifugation without stratification 22 months Comparative Example 1 Milky white, fine and even Centrifugation without stratification 8 months Comparative Example 2 Milky white, with fine and uniform particles Centrifugation without stratification 16 months Comparative Example 3 Milky white, coarse particles Centrifugal stratification 1 month Comparative Example 4 Milky white, with fine and uniform particles Centrifugation without stratification 8 months Comparative Example 5 Milky white, fine and even Centrifugation without stratification 13 months Comparative Example 6 Milky white, coarse particles Centrifugal stratification 5 months Comparative Example 7 Milky white, coarse particles Centrifugal stratification 4 months

[0088] As shown in Table 1, under the premise of using the same composite emulsifier as Example 2, Comparative Example 1 required a large amount of this composite emulsifier to prepare a milky white, fine, and uniform emulsified wax with the same appearance as Example 1. However, the static stability of Comparative Example 1 only reached 8 months. Compared with Example 4, Comparative Example 4 used cationic cellulose instead of cationic starch, and its emulsified wax stability decreased significantly. Compared with Example 2, Comparative Example 5 showed that using ordinary starch instead of cationic starch significantly improved the stability of the artificial board emulsified wax. However, Comparative Examples 2-7 omitted or replaced one component in the artificial board emulsified wax, and the artificial board emulsified waxes prepared in these comparative examples had poor appearance and stability. The embodiments of the present invention, by introducing cationic starch and liquid polybutadiene, and the strong synergistic effect between the composite emulsifier, significantly reduced the amount of emulsifier used while reducing production costs, greatly improved the static stability of the artificial board emulsified wax, and did not separate after standing for more than 20 months.

[0089] Experimental Example 2

[0090] The artificial board emulsion waxes prepared in the above embodiments and comparative examples were applied to fiberboard according to the following methods:

[0091] Wood pulp is mixed with urea-formaldehyde resin (Xinlai Plastic Synthetic Materials Additives Factory) and wood-based panel emulsion wax. The resulting mixture is then laid out to obtain fiberboard blanks. The fiberboard blanks are then pre-pressed at 50℃ and 1.2MPa, and hot-pressed at 200℃ and 3.0MPa to obtain wood-based panels. The amount of wood-based panel emulsion wax used per cubic meter of wood-based panel material is 6 kg / m³. 3 The amount of urea-formaldehyde resin adhesive used is 80 kg / m³. 3 The obtained engineered wood panels were subjected to waterproof performance and strength tests (GB / T17657), and the results are shown in Table 2. The waterproof performance of the engineered wood panels was tested according to the method in GB / T11718-2009 "Medium-density fiberboard".

[0092] Table 2

[0093]

[0094]

[0095] As shown in Table 2, the engineered wood panels prepared using the engineered wood panel emulsion wax of the present invention exhibit superior waterproof performance and internal bond strength compared to the comparative example. Therefore, it can be concluded that the engineered wood panels prepared using the engineered wood panel emulsion wax provided by the present invention possess excellent dimensional stability, good waterproof performance, and improved mechanical strength.

[0096] In summary, the artificial board emulsified wax provided by this invention has advantages such as low emulsifier dosage, good emulsification effect, good waterproof performance, and good stability. It can be mass-produced industrially, with simple process steps, convenient operation and control, high production efficiency, and low production cost. The artificial board emulsified wax provided by this invention is very suitable for use as a waterproofing agent in artificial boards, and can completely replace solid paraffin wax used in artificial board processing to obtain waterproof and moisture-proof artificial boards with excellent dimensional stability, without adversely affecting the mechanical properties of the artificial boards.

[0097] Of course, the present invention may have other embodiments and variations. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and variations according to the present invention, but these corresponding changes and variations should all fall within the protection scope of the claims of the present invention.

Claims

1. A type of emulsified wax for engineered wood panels, characterized in that, By weight percentage, it includes the following raw materials: paraffin wax 25%–40%, composite emulsifier 3%–5%, cationic starch 2%–4%, liquid polybutadiene 3%–7%, and water 44%–67%; The composite emulsifier is a nonionic emulsifier with a hydrophilic-lipophilic balance value of 9-10.

2. The artificial board emulsion wax as described in claim 1, characterized in that, By weight percentage, the artificial board emulsified wax comprises the following raw materials: paraffin wax 30%–35%, composite emulsifier 3.5%–4.5%, cationic starch 3%–3.5%, liquid polybutadiene 5%–6%, and water 51%–58.5%.

3. The artificial board emulsion wax as described in claim 1 or 2, characterized in that, The cationic starch is selected from quaternary ammonium salt cationic starch or etherified cationic starch; preferably, the etherified cationic starch is selected from tertiary ammonium alkyl ether starch or quaternary ammonium alkyl ether starch.

4. The artificial board emulsion wax as described in claim 1 or 2, characterized in that, The number-average molecular weight of the liquid polybutadiene is 500-8000, preferably 800-5000.

5. The artificial board emulsion wax as described in claim 1 or 2, characterized in that, The composite emulsifier is selected from any two of Tween 80, Tween 60, Span 80 and Span 60.

6. The artificial board emulsion wax as described in claim 1 or 2, characterized in that, The paraffin wax is selected from fully refined paraffin wax or semi-refined paraffin wax, with semi-refined paraffin wax being preferred.

7. A method for preparing the artificial board emulsion wax according to any one of claims 1-6, characterized in that, Includes the following steps: Paraffin wax and liquid polybutadiene are mixed and heated until the paraffin wax is completely melted. Then, a composite emulsifier, cationic starch, and boiling water are added and mixed. The mixture is then cooled to 60-75°C and homogenized into an emulsion to obtain artificial board emulsion wax.

8. The method for preparing the artificial board emulsion wax as described in claim 7, characterized in that, The heating temperature is 80-90°C, and the mixing time is 5-15 minutes.

9. A method for preparing a type of engineered wood panel, characterized in that, Includes the following steps: Wood pulp is mixed with adhesives and emulsified wax to obtain a mixture, which is then sequentially laid, pre-pressed, and hot-pressed to obtain engineered wood panels. The emulsified wax is selected from the artificial board emulsified wax according to any one of claims 1-6 or the artificial board emulsified wax prepared by the preparation method of the artificial board emulsified wax according to claim 7 or 8. Preferably, the adhesive is selected from urea-formaldehyde resin.

10. A type of engineered wood panel prepared by the method of claim 9, characterized in that, In each cubic meter of engineered wood panel, the amount of emulsified wax is 4-8 kg and the amount of adhesive is 70-90 kg.

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