Environment-friendly lycoris starch-vinyl acetate adhesive and preparation method thereof

Abstract

The invention relates to the technical field of adhesives, and discloses an environment-friendly lycoris starch-vinyl acetate adhesive and a preparation method thereof.The preparation method comprises the steps that water is added into a reaction kettle and stirred, a defoaming agent and polyvinyl alcohol are added, the mixture is heated to 85 DEG C and then self-heated to 90 DEG C, and heat preservation is conducted; cooling to 83 DEG C, adding an emulsifier and part of an initiator, sealing and starting a condenser; slowly dropwise adding vinyl acetate, maintaining the temperature at 77-80 DEG C, and supplementing the initiator every 30 minutes; after dropwise adding, adding the rest initiator, heating to 86 DEG C, and preserving heat; cooling to 83 DEG C, slowly adding lycoris starch paste, and gelatinizing for 30 minutes; and cooling to 65 DEG C, adding the plasticizer dibutyl phthalate, cooling to 50 DEG C, adding the preservative, stirring for 30 minutes, filtering, and packaging to obtain the finished product adhesive. The lycoris starch is introduced into a polyvinyl alcohol-vinyl acetate system, so that the prepared adhesive has the characteristics of high bonding strength, stable viscosity, slight smell and environmental friendliness.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of adhesives, in particular to an environment-friendly stone garlic starch-vinyl acetate adhesive and a preparation method thereof. BACKGROUND

[0002] As an important auxiliary material in paper processing, packaging printing, binding and compounding industries, the performance of the adhesive directly affects the bonding strength, appearance quality and safety of the product. At present, the commonly used adhesives are mainly prepared by free radical polymerization reaction using polyvinyl alcohol, vinyl acetate monomer and its emulsion as the main raw material. This kind of product has certain film-forming property and initial adhesion, but there are still some problems in long-term use: firstly, the adhesive with polyvinyl alcohol and vinyl acetate as the matrix has limited bonding strength, especially under high load or high humidity conditions, which is prone to delamination and cracking; secondly, the traditional adhesive system has high dependence on petroleum-based monomers, which increases the production cost and environmental pressure, and is difficult to meet the current requirements of green environmental protection and renewable resource utilization; thirdly, the stability of some adhesives is insufficient during the synthesis process, and the emulsion particle size distribution is uneven, resulting in poor product storage performance and prone to delamination, precipitation and unstable film during use; fourthly, many products have strong odor of acetic acid or organic solvents, which is not conducive to improving the operating environment and protecting the health of workers.

[0003] In recent years, natural starch has been widely studied as a modified raw material for adhesives due to its wide source, renewability, non-toxicity and low cost. Common starches include corn starch, potato starch and cassava starch, etc. However, these starches have problems such as fast aging speed, large viscosity fluctuation and insufficient water resistance, which limit their application in high-performance adhesives. The bulbs of stone garlic plants are rich in starch, which has the characteristics of small particle size, good dispersity and low gelatinization temperature. However, the existing technology has less application research on stone garlic starch in the vinyl acetate adhesive system, which fails to fully utilize its dual advantages of enhancement and environmental protection.

[0004] Therefore, how to reasonably introduce stone garlic starch while maintaining the bonding performance of polyvinyl alcohol-vinyl acetate matrix, so that the adhesive has high bonding strength, stable rheological property, good storage performance and low odor characteristics, has become a technical problem to be solved in the field. SUMMARY

[0005] In view of this, the present application provides an environment-friendly stone garlic starch-vinyl acetate adhesive and a preparation method thereof, which aims to solve the problems existing in the above content.

[0006] On the one hand, the present application provides a preparation method of an environment-friendly stone garlic starch-vinyl acetate adhesive, which comprises the following steps:

[0007] (1) Add water into the reactor and start stirring, the stirring speed is 65 rpm, add defoaming agent and polyvinyl alcohol successively, heat to 85℃, stop heating and rely on the system to rise to 90℃, keep for 30 minutes, so that the polyvinyl alcohol is completely dissolved;

[0008] (2) Cool to 83℃, add emulsifier OP-10, and add one-third volume of initiator ammonium persulfate solution, start circulating water of the condenser and seal the reactor;

[0009] (3) Slowly add vinyl acetate dropwise under stirring, the dropwise time is controlled in 2.5-3 hours, the reaction temperature is maintained at 77-80℃, and the remaining initiator solution is added once every 30 minutes during the dropwise process;

[0010] (4) After the addition of vinyl acetate is completed, the remaining initiator solution is added, the reaction temperature is raised to 86℃ and kept for 1 hour;

[0011] (5) After the keeping is finished, cool to 83℃, add water in the dispersion barrel, disperse and stir the lycoris tuber starch to form starch slurry, then slowly add into the reactor, and gelatinize at 83℃ for 30 minutes;

[0012] (6) Cool to 65℃, add plasticizer dibutyl phthalate and stir uniformly;

[0013] (7) Further cool to 50℃, add preservative, continue stirring for 30 minutes, filter and package, to obtain the environment-friendly lycoris tuber starch-vinyl acetate adhesive.

[0014] Further, the addition amount of the defoaming agent is 1.5 parts, the addition amount of the polyvinyl alcohol is 55 parts, the addition amount of the vinyl acetate is 138 parts, the addition amount of the lycoris tuber starch is 40 parts, the addition amount of the emulsifier OP-10 is 1.3 parts, the addition amount of the initiator ammonium persulfate is 1.1 parts, and the addition amount of the plasticizer dibutyl phthalate is 8 parts, and the addition amount of the preservative is 2.5 parts.

[0015] Further, the lycoris tuber starch slurry in step (5) is prepared by high-speed stirring at room temperature, and then added into the reactor after the lycoris tuber starch is completely dispersed and uniform.

[0016] Further, the lycoris tuber starch is prepared by the following method:

[0017] The lily bulb is washed and dried at 45-50 DEG C until the moisture content is less than or equal to 14%, and then crushed to pass through an 80-mesh sieve; a starch slurry is prepared by mixing the crushed lily bulb with water at a liquid-to-solid ratio of 1:7; citric acid buffer is added to the starch slurry to adjust the pH to 5.0-5.5, and strong acid cation exchange resin is added and stirred for 30-60 min to remove alkaloids, and then the starch slurry is subjected to 3-5 times volume replacement through an ultrafiltration membrane with a molecular weight cut-off of 10000 until the conductivity is less than or equal to 1500 muS / cm; the obtained starch slurry is deoxygenated under nitrogen protection until the dissolved oxygen is less than or equal to 0.5 mg / L, and then 0.02-0.05% of the starch dry basis is added as a particle stabilizer, and the pH is adjusted to 6.0-6.5; under this condition, microfine gas is introduced to form a microbubble phase, and alpha amylase is added in a 2-3 times pulse mode, with a single enzymolysis time of 5-7 min, an intermediate interval of 3-5 min, and a total enzymolysis time of 12-18 min, and then the temperature is raised to 75 DEG C for 5-10 min to inactivate the enzyme; the slurry is subjected to limited gelatinization at a shear rate of 50-150 for 20-30 min, and then spray dried at an inlet temperature of 150-170 DEG C and an outlet temperature of 75-85 DEG C, and then fluidized bed dried at 60-65 DEG C until the moisture content is less than or equal to 12%, and then passed through a 120-mesh sieve to obtain lily bulb starch, which has a microporous structure of 0.5-2.5 mu m on the surface of the particles, a pore density of greater than or equal to 6x 10^11 pores / g, a combined phosphorus content of 0.02-0.05%, a cold water solubility of less than or equal to 3%, and a gelatinization temperature that is 3-5 DEG C higher than that of original lily bulb starch.

[0018] In another aspect, the present application provides an environmentally friendly lily bulb starch-vinyl acetate adhesive, which is composed of the following raw materials in parts by weight: polyvinyl alcohol 55 parts, defoaming agent 1.5 parts, emulsifier OP-10 1.3 parts, initiator ammonium persulfate 1.1 part, vinyl acetate 138 parts, lily bulb starch 40 parts, plasticizer dibutyl phthalate 8 parts, and preservative 2.5 parts.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] First, in terms of solid content, the solid content of the adhesive obtained by the present application is 16%, which not only ensures the construction fluidity of the system, but also maintains a relatively high concentration of effective components. If the solid content is too low, the bonding layer strength will be insufficient, and if the solid content is too high, the operation difficulty and energy consumption will be increased. The balance of the present application in this parameter makes the product have good adaptability in various construction methods such as spraying, rolling and brushing, reduces the risk of equipment blockage, and improves the coating uniformity.

[0021] Secondly, in terms of acidity and alkalinity, the pH value of the adhesive is 4.8, which is weakly acidic, can effectively stabilize the dispersion state of polyvinyl alcohol and vinyl acetate emulsion, and promote the interaction between the stone garlic starch and the base molecules. Compared with strong acid or strong alkali system, the weakly acidic condition avoids chemical corrosion and degradation of paper fibers, thereby improving the application range of the adhesive and the compatibility with different paper-based materials.

[0022] Thirdly, in terms of rheological properties, the viscosity measured at 25℃ is 46748 mPa·s (4th rotor, 12 revolutions / min), which shows strong cohesion and film forming ability. This viscosity level not only ensures good operability of the colloid during use, but also quickly forms a stable adhesive film after coating, avoiding the problems of easy dripping, penetration or difficult curing of traditional adhesives, ensuring the uniformity and stability of the adhesive layer.

[0023] In addition, in terms of odor, the adhesive only shows a weak vinegar smell, which is much lower than the irritating odor of ordinary vinyl acetate-based adhesives. This feature significantly improves the construction and production environment, reduces the respiratory discomfort and occupational hazards that may occur during long-term contact by operators, meets the basic requirements of green and environmentally friendly products, and is more convenient to apply in fields sensitive to odor such as food packaging and bookbinding.

[0024] Further, the adhesive performs outstandingly in the bonding performance test. When the adhesive is applied to the bonding of corrugated paper and white card paper, 100% of the paper fibers are destroyed, indicating that the bonding strength has exceeded the strength limit of the paper itself. Compared with traditional adhesives, the present invention not only improves the cohesive strength of the adhesive layer, but also enhances the infiltration and combination of the paper fibers, thereby ensuring that the bonding effect remains firm under complex environments such as transportation, stacking, humidity changes and stress impact.

[0025] At the same time, the polymerization process of the present invention uses a segmented dropping and multiple initiation method, which avoids uneven particle size and system instability caused by instantaneous polymerization of monomers through strict temperature and time control during the reaction. This process ensures the uniformity of the emulsion particle size distribution and the long-term stability of the emulsion, resulting in an adhesive that not only has good storage stability, but also is less likely to separate, precipitate or clog during use, improving the operability and shelf life of the product.

[0026] In addition, the present invention introduces stone garlic starch as a partial replacement of raw materials, making full use of natural renewable resources. After gelatinization, stone garlic starch can form a multi-point network with polyvinyl alcohol and vinyl acetate, improving the film density and bonding strength of the adhesive. At the same time, the addition of stone garlic starch effectively reduces the consumption proportion of petroleum-based monomers, reducing production costs. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of them. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0028] In the following embodiments, the lycoris starch is specifically prepared by the following method:

[0029] 1. Raw material pretreatment

[0030] 10.0 kg of fresh lycoris bulbs were selected, washed to remove impurities, and then sliced, and dried by hot air at 45-50°C until the moisture content was ≤14%. The dried slices were crushed, sieved through an 80-mesh sieve, and 3.80 kg of lycoris starch coarse powder was obtained.

[0031] 2. Slurry preparation and removal of alkaloids

[0032] The coarse powder was added to 26.6 kg of deionized water to prepare a starch slurry according to a liquid-to-solid ratio of 1:7. The pH was adjusted to 5.2 using a citric acid / sodium citrate buffer. 0.30 kg of strong acid cation exchange resin wet resin was added, and stirred for 45 min. Cross-flow displacement was performed through an ultrafiltration membrane with a molecular weight cutoff of 10,000, for 4 volumes, and the conductivity of the effluent was ≤1500 μS / cm.

[0033] 3. Deoxygenation and particle stabilization

[0034] Deoxygenation was performed under nitrogen protection by microporous aeration, with an in-line dissolved oxygen content of ≤0.5 mg / L. 0.03% of a solution based on the dry starch basis was added to form stable microbubbles. The pH was adjusted to 6.3.

[0035] 4. Mild surface enzyme etching (pulse enzyme addition)

[0036] Fine microbubbles were formed. α-amylase was added in three pulses at 45°C, with a total enzyme amount of 30 U / g of dry starch basis; single enzyme hydrolysis was performed for 6 min, with an interval of 4 min. After the pulse was completed, the temperature was increased to 75°C for 8 min to inactivate the enzyme.

[0037] 5. Limited gelatinization and resuscitation

[0038] Limited gelatinization was performed at 58-62°C with a shear rate of about 100 for 25 min, to obtain a starch slurry with a slightly etched shell and a retained core crystal region.

[0039] 6. Drying and classification

[0040] ​Spray drying, inlet 160℃, outlet 80℃; followed by fluid bed drying 60-65℃ to final moisture <12%. Sieved through 120 mesh, and 3.25 kg of refined Lycoris squillata starch powder was obtained.

[0041] Example 1

[0042] The raw materials were taken by weight parts as follows: polyvinyl alcohol 55 parts, defoaming agent 1.5 parts, emulsifier OP-10 1.3 parts, initiator ammonium persulfate 1.1 parts, vinyl acetate 138 parts, Lycoris squillata starch 40 parts, plasticizer dioctyl phthalate (DOP) 8 parts, preservative 2.5 parts.

[0043] Water was added to the reaction kettle, and the stirring speed was controlled at 65 rpm. Defoaming agent and polyvinyl alcohol were added in turn, heated to 85℃ and relied on self-heating to 90℃, and kept for 30 min until the polyvinyl alcohol was completely dissolved; after cooling to 83℃, one-third of the emulsifier OP-10 and ammonium persulfate solution was added, the reaction kettle was sealed and the condenser was started; under stirring, slowly add vinyl acetate, dropwise time 2.5-3h, temperature control at 77-80℃, every 30 min during the dropwise process, add the remaining initiator solution; after the dropwise addition was completed, the remaining initiator was added, and the temperature was raised to 86℃ and kept for 1h; cool to 83℃, make a pulp of Lycoris squillata starch and water in a dispersion barrel and slowly add it to the reaction kettle, gelatinize for 30 min; the system is reduced to 65℃, dioctyl phthalate is added and stirred evenly; then reduce to 50℃, add preservative and stir for 30 min, filter and package to obtain the adhesive product.

[0044] The obtained adhesive was tested for performance, and the results were as follows: solid content was 16%, pH value was 4.8; at 25℃, using rotor No. 4, 12 rpm, the viscosity was measured to be 46748 mPa·s; the odor was weak vinegar; the adhesive was coated on corrugated paper and white cardboard, and the bonding strength test showed that the paper fiber was 100% broken, indicating that the adhesive had excellent bonding force on paper-based materials.

[0045] Comparative Example 1

[0046] Except that Lycoris squillata starch was not added, the other raw materials and operation steps were the same as in the example. The test results of the obtained adhesive were as follows: solid content 15%, pH value 4.7; viscosity 25630 mPa·s was measured at 25℃, rotor No. 4, 12 rpm; in the paper bonding test, only about 70% of the paper fiber was broken, and local delamination occurred, and the product odor was obviously heavier.

[0047] Comparative Example 2

[0048] The same amount of corn starch was used to replace the lycoris starch, and other conditions were the same as in the example. The test results of the obtained adhesive were as follows: solid content 16%, pH value 4.9; viscosity 31250 mPa·s; paper fiber damage rate about 85%, and some samples showed adhesive layer peeling; after storage for 1 month, the emulsion showed slight stratification.

[0049] Comparative Example 3

[0050] The lycoris starch was not gelatinized, but was directly added after dispersion at room temperature, and other conditions were unchanged. The test results were as follows: solid content 16%, pH value 4.8; viscosity 28900 mPa·s, obvious particle feeling existed during use, the bonding strength decreased, and the paper fiber damage rate was about 80%.

[0051] Comparative Example 4

[0052] The vinyl acetate monomer was quickly added within 1 hour, and other conditions were unchanged. The test results were as follows: solid content 16%, pH value 4.8; viscosity fluctuated greatly, in the range of 21000-28000 mPa·s; the paper fiber damage rate was less than 85%, and the product stability decreased.

[0053] Comparative Example 5

[0054] The initiator ammonium persulfate was added at once at the beginning of polymerization, without fractionally supplementing. The viscosity of the obtained product was 24300 mPa·s; the emulsion particles were coarse, and showed a sedimentation trend; the bonding strength decreased, and the paper fiber damage rate was about 75%.

[0055] Comparative Example 6

[0056] No emulsifier OP-10 was added, and other conditions were the same. The obtained product showed uneven particle size distribution and agglomeration, and was difficult to filter; the viscosity was 19800 mPa·s; and the paper fiber damage rate was less than 60%.

[0057] By comparing the test results of the examples and comparative examples 1-6, it can be seen that:

[0058] I. Bonding strength comparison

[0059] The adhesive of the embodiment achieves 100% paper fiber damage rate on the bonding strength test of corrugated paper and white cardboard, indicating that the adhesive layer bonding force has exceeded the mechanical strength of the paper itself, and the bonding effect reaches the ideal level. In contrast, the paper fiber damage rate of Comparative Example 1 is only about 70% due to the absence of stone garlic starch, and obvious adhesive separation occurs; the fiber damage rate of Comparative Example 2 is less than 85% even though corn starch is added, and the adhesive layer is still broken; the fiber damage rate of Comparative Example 3 is only about 80% due to uneven dispersion of the starch which has not been gelatinized; the fiber damage rate of Comparative Example 4 is less than 85% due to uneven polymerization caused by rapid monomer dropping; the damage rate of Comparative Example 5 is about 75% due to the low adhesive layer bonding force caused by one-time addition of the initiator; and the damage rate of Comparative Example 6 is less than 60% due to poor dispersion of the system and weaker bonding effect. These comparative results fully show that the introduction and gelatinization treatment of stone garlic starch are key factors for improving the bonding strength of the adhesive.

[0060] II. Viscosity and Rheological Property Comparison

[0061] The viscosity of the product of the embodiment is 46748 mPa·s at 25°C, 4 rotor, and 12 revolutions per minute, which is significantly higher than that of all comparative examples, indicating that the adhesive is dense, flows uniformly, and is not prone to sagging, which can ensure the formation of a stable adhesive film after coating. Comparative Example 1 has a viscosity of less than 26000 mPa·s, and the coating is prone to sliding; the viscosity of Comparative Examples 2 and 3 is increased to about 31000 mPa·s, but it is still lower than that of the embodiment, and the coating film density is insufficient; the viscosity of Comparative Example 4 fluctuates in the range of 21000-28000 mPa·s, which makes it difficult to ensure batch consistency; the viscosity of Comparative Example 5 is only 24300 mPa·s, which is obviously insufficient; and the viscosity of Comparative Example 6 is even lower, only less than 20000 mPa·s, and the adhesive layer is prone to uneven flow. The comparison results show that the gelatinization of the stone garlic starch slurry in the embodiment enables the system to form a stronger network structure, thereby significantly improving the overall viscosity level and use stability.

[0062] III. Odor and Environmental Friendliness Comparison

[0063] The odor of the adhesive of the embodiment is only weakly acetic, which causes little irritation to personnel during operation and meets the requirements of environmental protection and occupational safety. In contrast, Comparative Examples 1 and 2 have a relatively strong acetic odor, which is not conducive to the working environment; Comparative Examples 3, 4, 5, and 6 have more by-products and more residual monomers during polymerization or dispersion, and the odor is also relatively heavy. Therefore, the present invention has obvious advantages in reducing odor intensity, and the product is more suitable for use in packaging, printing, binding, and other occasions that require environmental friendliness and low odor.

[0064] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application but not to limit it. Although the present application has been described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the specific embodiments of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and any modification or equivalent replacement should be covered in the protection scope of the claims of the present application.

Claims

1. A method for preparing an environmentally friendly Lycoris radiata starch-vinyl acetate adhesive, characterized in that, Includes the following steps: (1) Add water to the reactor and start stirring at a speed of 65 rpm. Add defoamer and polyvinyl alcohol in sequence, heat to 85°C, stop heating and let the system heat up to 90°C by itself, keep warm for 30 minutes to completely dissolve polyvinyl alcohol. (2) Cool down to 83°C, add emulsifier OP-10, and add one-third volume of initiator ammonium persulfate solution. Turn on the condenser circulating water and seal the reactor. (3) Add vinyl acetate slowly under stirring, with the addition time controlled at 2.5-3 hours and the reaction temperature maintained at 77-80℃. During the addition process, add the remaining initiator solution every 30 minutes. (4) After the vinyl acetate is added, add the remaining initiator solution, raise the reaction temperature to 86°C and keep it at that temperature for 1 hour. (5) After the heat preservation is completed, the temperature is reduced to 83°C. Water is added to the dispersion tank to disperse and stir the Lycoris radiata starch to form a starch slurry. Then, it is slowly added to the reaction vessel and gelatinized at 83°C for 30 minutes. (6) Cool down to 65°C, add plasticizer dibutyl phthalate, and stir until uniform; (7) Cool down to 50°C, add preservative, continue stirring for 30 minutes, filter and package to obtain environmentally friendly Lycoris starch-vinyl acetate adhesive.

2. The preparation method of the environmentally friendly Lycoris radiata starch-vinyl acetate adhesive according to claim 1, characterized in that, The amount of defoamer added is 1.5 parts, the amount of polyvinyl alcohol added is 55 parts, the amount of vinyl acetate added is 138 parts, the amount of Lycoris radiata starch added is 40 parts, the amount of emulsifier OP-10 added is 1.3 parts, the amount of initiator ammonium persulfate added is 1.1 parts, the amount of plasticizer dibutyl phthalate added is 8 parts, and the amount of preservative added is 2.5 parts.

3. The preparation method of the environmentally friendly Lycoris radiata starch-vinyl acetate adhesive according to claim 1, characterized in that, The Lycoris starch slurry in step (5) is prepared by high-speed stirring at room temperature until the Lycoris starch is completely and evenly dispersed before being added to the reaction vessel.

4. The preparation method of the environmentally friendly Lycoris radiata starch-vinyl acetate adhesive according to claim 1, characterized in that, The Lycoris starch is prepared by the following method: Wash the Lycoris bulbs and dry them at 45-50℃ until the moisture content is ≤14%. After crushing them through an 80-mesh sieve, prepare starch slurry at a liquid-to-solid ratio of 1:

7. Adjust the pH of the starch slurry to 5.0-5.5 by adding citrate buffer. Add a strongly acidic cation exchange resin and stir for 30-60 minutes to remove alkaloids. Then, pass the slurry through an ultrafiltration membrane with a molecular weight cutoff of 10,000 for 3-5 times volume replacement until the conductivity is ≤1500 μS / cm. Deoxygenate the resulting starch slurry under nitrogen protection until the dissolved oxygen is ≤0.5 mg / L, and then add... A granule stabilizer was used at a ratio of 0.02-0.05% of the dry starch basis, and the pH was adjusted to 6.0-6.5; under these conditions, micro-fine particles were introduced. The gas forms a microbubble phase. α-Amylase is added in 2-3 pulsed increments, with each enzymatic hydrolysis session lasting 5-7 minutes, followed by a 3-5 minute interval, for a total hydrolysis time of 12-18 minutes. The temperature is then raised to 75°C and held for 5-10 minutes to inactivate the enzyme. The slurry is then subjected to a shear rate of 50-150 at 58-62°C. Restricted gelatinization for 20-30 minutes, followed by spray drying at an inlet air temperature of 150-170℃ and an outlet air temperature of 75-85℃, and then fluidized bed drying at 60-65℃ until the moisture content is ≤12%. The product is then passed through a 120-mesh sieve to obtain Lycoris radiata starch. The granules have a microporous structure of 0.5-2.5 μm on their surface, with a pore density ≥6× Pores / g, bound phosphorus content 0.02-0.05%, cold water solubility ≤3%, gelatinization temperature 3-5℃ higher than that of original Lycoris radiata starch.

5. An environmentally friendly Lycoris radiata starch-vinyl acetate adhesive, characterized in that, It is composed of the following raw materials in parts by weight: 55 parts polyvinyl alcohol, 1.5 parts defoamer, 1.3 parts emulsifier OP-10, 1.1 parts initiator ammonium persulfate, 138 parts vinyl acetate, 40 parts Lycoris starch, 8 parts plasticizer dibutyl phthalate, and 2.5 parts preservative.