Method for realizing anti-caking of acrylic resin powder
By uniformly mixing and drying the undried solid acrylic resin with an amine compound aqueous solution or dispersion, the problem of easy acrylic resin powder is solved, and the efficient anti-caking effect is achieved, and it is easy to operate and suitable for industrial applications.
Patent Information
- Application Number
- CN202411945378.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-03-04
AI Technical Summary
Acrylic resin powder is prone to agglomeration, resulting in reduced production efficiency, decreased product quality, increased safety hazards, difficulty in storage and transportation, and environmental pollution. Existing anti-caking agents affect product performance at high doses.
The solid acrylic resin that has completed the polymerization reaction and is not dried is uniformly mixed with an amine compound solution or dispersion, and then dried to a constant weight at 30 to 50°C. The amine compound solution or dispersion used is prepared by dissolving or dispersing it in water, and the amount is 0.005% to 1% relative to the total mass of the polymerization monomer of the solid acrylic resin.
It achieves excellent anti-caking performance of acrylic resin powder, the amount of amine compounds is small and does not affect the resin performance, and there is no need to change the existing production equipment and processes. It is easy to operate, universal and repeatable, and is easy to industrially apply.
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Abstract
Description
Technical Field
[0001] The invention relates to a method for achieving anti-caking of acrylic resin powder, and belongs to the technical field of acrylic resin. Background Art
[0002] Powder agglomeration refers to the phenomenon that powder particles aggregate together to form larger lumps due to factors such as temperature, moisture, static electricity, pressure, and time. For polymers, agglomeration is also directly related to the glass transition temperature (Tg) of the polymer itself and the amount of residual monomers. For example, acrylic resin powders with a Tg between 10 and 60°C are more likely to agglomerate under normal conditions, especially when left for a long time, squeezed, or at high temperatures.
[0003] Powder agglomeration can cause a series of hazards, including but not limited to:
[0004] 1) Reduced production efficiency: Powder agglomeration will cause blockage of conveying equipment, increase equipment maintenance and downtime, and thus reduce production efficiency; in addition, additional steps are required to break up the agglomerates during the production process, which increases the complexity and time cost of the production process;
[0005] 2) Product quality deterioration: Powder agglomeration will lead to uneven product formulation, affecting the quality and consistency of the final product; in addition, agglomerates may also cause changes in the physical properties of the product (such as fluidity and solubility), thereby affecting product performance;
[0006] 3) Safety hazards: Powder agglomeration may cause equipment failure or damage, increase maintenance costs and safety risks. In addition, some powder materials may produce mechanical stress or chemical reactions after agglomeration, posing a potential risk of explosion or fire.
[0007] 4) Storage and transportation issues: Agglomerated powders are prone to deterioration or failure during storage, affecting shelf life and usage effects; and agglomerated powders during transportation may increase handling difficulty and transportation costs;
[0008] 5) Environmental pollution: Dust may be generated during the powder agglomeration process, causing air pollution and deterioration of the working environment, endangering the health of employees.
[0009] In order to prevent powder agglomeration, the following measures are usually taken:
[0010] 1) Control humidity: keep the powder environment dry to avoid moisture intrusion;
[0011] 2) Adding anti-caking agent: Add a certain amount of anti-caking agent to the powder to reduce the adhesion between particles. The common method is to mechanically mix a small amount of anti-caking agent with the powder product;
[0012] 3) Improve packaging and storage conditions: Use moisture-proof packaging and optimize the storage environment to reduce the risk of powder agglomeration.
[0013] Since adding anti-caking agents can fundamentally improve the anti-caking performance of powders relative to controlling humidity and improving packaging and storage conditions, currently the main way to prevent powders from agglomerating is to add anti-caking agents.
[0014] At present, the commonly used anti-caking additives are mainly divided into two categories. One is inorganic materials, such as silicon dioxide, calcium carbonate, calcium phosphate, magnesium oxide, etc.; the other is low surface energy, low polarity organic materials, such as paraffin, stearic acid, stearyl alcohol, etc. However, inorganic anti-caking additives are not suitable for acrylic resins in many cases. This is because acrylic resins often need to be dissolved in organic solvents or polymerized monomers, and these inorganic anti-caking additives cannot be dissolved in organic solvents or polymerized monomers. Although organic anti-caking additives can be used for acrylic resins compared to inorganic anti-caking additives, they must be added in larger amounts (>5wt%) when used. If the addition amount is less than 1%, the anti-caking effect is very limited and almost negligible, and high addition amounts often lead to significant changes in the performance of acrylic resin products. Summary of the invention
[0015] In view of the above problems existing in the prior art, the object of the present invention is to provide a method for achieving anti-caking of acrylic resin powder.
[0016] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:
[0017] A method for achieving anti-caking of acrylic resin powder comprises the following steps: uniformly mixing a solid acrylic resin that has completed polymerization reaction and post-treatment but has not been dried with a solution or dispersion of an anti-caking aid, and then drying the resulting mixture at 30-50°C to a constant weight; the solution or dispersion of the anti-caking aid is prepared by dissolving or dispersing an amine compound in water; and the amount of the solution or dispersion of the anti-caking aid is such that the mass of the amine compound is 0.005%-1% of the total mass of the monomers in the solid acrylic resin polymerization reaction.
[0018] In one embodiment, the amount of the amine compound used is 0.01% to 1% of the total mass of the solid acrylic resin polymerization reaction monomers, preferably 0.05% to 0.5%.
[0019] In one embodiment, the content of the amine compound in the solution or dispersion of the anti-caking aid is 0.05 wt % to 5 wt %.
[0020] In one embodiment, the boiling point of the amine compound is >130°C, preferably >150°C.
[0021] In one embodiment, the amine compound is selected from at least one of aliphatic amine compounds, aromatic amine compounds, and amine ether compounds.
[0022] In a preferred embodiment, the aliphatic amine compound is at least one selected from aliphatic primary amine compounds, aliphatic secondary amine compounds, and aliphatic tertiary amine compounds.
[0023] In a preferred embodiment, the aliphatic primary amine compound is selected from at least one of C4-C22 alkylamines (for example, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, nonadecylamine, eicosylamine, didecylamine, and diundecylamine), ethanolamine, and propanolamine, and is most preferably selected from at least one of C8-C22 alkylamines, ethanolamine, and propanolamine.
[0024] In a preferred embodiment, the aliphatic secondary amine compound is selected from at least one of diisopropylamine, dibutylamine, N-methylethanolamine and diethanolamine, and at least one of N-methylethanolamine and diethanolamine is the most preferred.
[0025] The aliphatic tertiary amine compound is at least one selected from N,N-dimethylethanolamine, N,N-dimethylaminoethyl methacrylate, N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)-ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine, and at least one selected from N,N-dimethylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, and triethanolamine is the best.
[0026] In a preferred embodiment, the aromatic amine compound is selected from N,N-bis-(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis-(2-hydroxyethyl)-p-toluidine, N,N-bis-(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis-(2-hydroxyethyl)-4-ethylaniline, N,N-bis-(2-hydroxyethyl)-4-isopropylaniline, N,N-bis-(2-hydroxyethyl)-4-tert-butylaniline, N,N-bis-(2-hydroxyethyl)-3,5-diisopropylaniline, N,N-bis-(2-hydroxyethyl)-3,5-di-tert-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, N,N-diethyl-p-toluidine At least one of 4-(N,N-dimethylamino)-1-(methacryloyloxy)-1-(4-(N,N-dimethylamino)-benzoic acid ethyl ester, 4-(N,N-dimethylamino)-1-(methacryloyloxy)-1-( ...
[0027] In a preferred embodiment, the amine ether compound is selected from at least one of bis(2-dimethylaminoethyl) ether and 2,2-dimorpholinyl diethyl ether, with 2,2-dimorpholinyl diethyl ether being the best.
[0028] Since most of the alcoholamine compounds are substances with low toxicity, low odor and high boiling point, the amine compounds described in the present invention are preferably alcoholamine compounds, such as ethanolamine, propanolamine, N-methylethanolamine, diethanolamine, N,N-dimethylethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, etc.
[0029] Compared with the prior art, the present invention has the following significant beneficial effects:
[0030] The present invention uses an aqueous solution or dispersion containing an amine compound to perform anti-caking modification treatment on solid acrylic resin that has completed polymerization reaction and post-treatment but has not been dried, so that not only can the obtained solid acrylic resin powder have excellent anti-caking performance, but also the amount of the amine compound used as an anti-caking auxiliary agent is very small, and there is no need to change the existing production equipment and polymerization process of the solid acrylic resin. The operation is simple and universal and repeatable, and it is easy to realize industrial application. Therefore, compared with the prior art, the present invention not only produces unexpected technical effects, but also has significant progress. DETAILED DESCRIPTION
[0031] The technical scheme of the present invention is further described in detail and completely below in conjunction with the examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually carried out under conventional conditions or according to the conditions recommended by the manufacturer.
[0032] The performance parameters of the anti-caking aids used in the following examples and comparative examples are shown in Table 1:
[0033] Table 1 Performance parameters of the anti-caking aids used in the examples and comparative examples
[0034]
[0035] Note: Paraffin wax* in Table 1 is a general term, usually referring to a mixture of hydrocarbons with different carbon atoms. The paraffin wax used in this application was purchased from the reagent store MERCK, which is a mixture of hydrocarbons with 18-30 carbon atoms.
[0036] Examples 1 to 7
[0037] a) 180 parts by mass of methyl methacrylate, 820 parts by mass of n-butyl methacrylate, 13 parts by mass of benzoyl peroxide, and 2 parts by mass of dodecyl mercaptan are pre-mixed to obtain an oil phase;
[0038] b) adding a certain volume (3 L for example) of deionized water and 1 part by mass of hydroxyethyl cellulose 250HBR into a batch reaction vessel, stirring and heating to 50° C. to obtain an aqueous phase;
[0039] c) adding the oil phase prepared in step a) to the water phase prepared in step b) (control the volume ratio of oil phase:water phase≈1:3, i.e., the volume of the added oil phase is 1 L, ignoring the effect of the dispersant in the water phase on the volume of the water phase, and directly taking the volume of the added deionized water as the volume of the water phase), and then stirring at 50° C. for 30 minutes;
[0040] d) Raise the temperature to 80°C, keep stirring and react for 4 hours; then raise the temperature to 95°C, keep stirring and react for another 2 hours;
[0041] e) ending the polymerization reaction, collecting the solid acrylic resin by standing and settling and filtering, and then washing the obtained solid acrylic resin;
[0042] f) Put the washed solid acrylic resin into a polymerization bag or a ziplock bag, add the pre-prepared anti-caking agent solution or dispersion into the bag, seal and knead to mix evenly, take out the obtained mixture and put it into a 30°C oven to dry to constant weight (usually takes 2 to 3 days), thus obtaining the anti-caking modified solid acrylic resin.
[0043] The solution or dispersion of the anti-caking aid is prepared by dissolving or dispersing the amine compound in the proportion shown in Table 2 in 80 g of water.
[0044] The weight average molecular weight of the solid acrylic resin prepared in the examples was measured by gel permeation chromatography (GPC) to be about 160,000. The Tg of the solid acrylic resin prepared in the examples was measured by differential scanning calorimetry (DSC) to be 42°C.
[0045] According to common knowledge, polymers will stick together when the temperature is significantly higher than their glass transition temperature, and powders that are prone to agglomeration will stick together after being treated at a higher temperature, thereby reducing the proportion of small particles and increasing the proportion of large particles. Therefore, the present invention bakes the resin sample in an oven at 65°C for 15 hours, and then sieves it through a 60-mesh sieve to test the change in particle size before and after treatment above the glass transition temperature, thereby judging the anti-caking performance of the resin sample based on the change in particle size. The specific test results are shown in Table 2.
[0046] It should be noted that Examples 1 to 7 all use existing polymerization processes to prepare solid acrylic resins, but the present invention is not limited to the polymerization processes described in the examples, and other existing polymerization processes for preparing solid acrylic resins may also be used; the purpose of the examples is only to examine the effect of anti-caking modification treatment of a solid acrylic resin that has completed polymerization reaction and post-treatment and has not been dried, using a solution or dispersion of the anti-caking aid described in the present invention; therefore, the present invention is not limited to a specific polymerization process for solid acrylic resin, as long as the obtained solid acrylic resin and the solution or dispersion of the anti-caking aid described in the present invention are first mixed evenly after the polymerization reaction and post-treatment and before drying, and then dried to constant weight.
[0047] In addition, the mixing operation of the solid acrylic resin and the solution or dispersion of the anti-caking aid is not limited to "putting into a polymerization bag or a ziplock bag and kneading" as described in the embodiments, and can also be put into other containers and industrial mixing machinery is used to achieve uniform mixing of the two.
[0048] Table 2 Type and amount of anti-caking aids in Examples 1 to 7 (percentage relative to the total mass of polymerization monomers) and test results of anti-caking properties of the obtained solid acrylic resin samples
[0049]
[0050] As can be seen from Table 2, after the solid acrylic resin samples obtained in the embodiments of the present invention were baked at a temperature higher than their glass transition temperature (Tg), the particle size did not change significantly, indicating that the method of the present invention can make the obtained acrylic resin powder have excellent anti-caking performance; and, in Table 2, the amount of the amine compound used as the anti-caking aid is only 0.01% to 0.39% of the total mass of the solid acrylic resin polymerization reaction monomer, which is less than 1%, indicating that the present invention can achieve the obtained acrylic resin powder having excellent anti-caking performance by using the solution or dispersion of the anti-caking aid to treat the solid acrylic resin that has completed the polymerization reaction and post-treatment and has not been dried, and a small amount of the anti-caking aid will not have a negative impact on the performance of the acrylic resin, and there is no need to change the existing production equipment and polymerization process of the solid acrylic resin, and there is basically no impact on the production cost; therefore, it can be shown that the present invention has produced significant progress and has significant industrial application value.
[0051] Comparative Examples 1 to 4
[0052] The difference between Comparative Examples 1 to 4 and Examples 1 to 7 is that:
[0053] In Comparative Example 1, no anti-caking agent was used for treatment. In Comparative Examples 2 to 4, the anti-caking agents used were not the amine compounds described in the present invention. The rest of the contents were the same as those described in Examples 1 to 7.
[0054] The anti-caking performance of the solid acrylic resin samples obtained in Comparative Examples 1 to 4 was tested by the same testing method as in the embodiment. The test results are shown in Table 3.
[0055] Table 3 Type and amount of anti-caking aids in Comparative Examples 1 to 4 (percentage relative to the total mass of polymerization monomers) and test results of anti-caking properties of the obtained solid acrylic resin samples
[0056]
[0057] It can be seen from Table 3 that when other conditions are the same, if no anti-caking agent is used, the anti-caking performance of the obtained solid acrylic resin will be poor. If traditional organic anti-caking agents (paraffin, stearic acid, stearyl alcohol) are used, the anti-caking effect is not obvious when the dosage is less than 1%. Only when the dosage is greater than 5% can a relatively obvious anti-caking effect be achieved.
[0058] Comparing the experimental results of Examples 1 to 7 shown in Table 2 with the experimental results of Comparative Examples 1 to 4 shown in Table 3, it can be seen that when other conditions are the same, the present invention adopts amine compounds as anti-caking aids. Compared with traditional organic anti-caking aids, a significant anti-caking effect can be obtained with a very small amount. Therefore, the present invention has unexpected technical effects and significant progress compared to the prior art.
[0059] Finally, it should be pointed out that the above are only some preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above contents of the present invention all fall within the scope of protection of the present invention.
Claims
1. A method for achieving anti-caking of acrylic resin powder, characterized in that: The method comprises the following steps: uniformly mixing a solid acrylic resin that has completed polymerization reaction and post-treatment but has not been dried with a solution or dispersion of an anti-caking aid, and then drying the obtained mixture at 30-50° C. to a constant weight; the solution or dispersion of the anti-caking aid is prepared by dissolving or dispersing an amine compound in water; and the amount of the solution or dispersion of the anti-caking aid is such that the mass of the amine compound therein is 0.005%-1% of the total mass of the monomers in the solid acrylic resin polymerization reaction.
2. The method for achieving anti-caking of acrylic resin powder according to claim 1, characterized in that: The amount of the amine compound used is 0.01% to 1% of the total mass of the solid acrylic resin polymerization reaction monomer.
3. The method for achieving anti-caking of acrylic resin powder according to claim 1, characterized in that: The amine compound is selected from at least one of aliphatic amine compounds, aromatic amine compounds and amine ether compounds.
4. The method for achieving anti-caking of acrylic resin powder according to claim 3, characterized in that: The aliphatic amine compound is selected from at least one of aliphatic primary amine compounds, aliphatic secondary amine compounds and aliphatic tertiary amine compounds.
5. The method for achieving anti-caking of acrylic resin powder according to claim 4, characterized in that: The aliphatic primary amine compound is selected from at least one of C4-C22 alkylamines, ethanolamine and propanolamine.
6. The method for achieving anti-caking of acrylic resin powder according to claim 4, characterized in that: The aliphatic secondary amine compound is at least one selected from diisopropylamine, dibutylamine, N-methylethanolamine and diethanolamine.
7. The method for achieving anti-caking of acrylic resin powder according to claim 4, characterized in that: The aliphatic tertiary amine compound is selected from at least one of N,N-dimethylethanolamine, N,N-dimethylaminoethyl methacrylate, N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)-ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine.
8. The method for achieving anti-caking of acrylic resin powder according to claim 3, characterized in that: The aromatic amine compound is selected from N,N-bis-(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis-(2-hydroxyethyl)-p-toluidine, N,N-bis-(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis-(2-hydroxyethyl)-4-ethylaniline, N,N-bis-(2-hydroxyethyl)-4-isopropylaniline, N,N-bis-(2-hydroxyethyl)-4-tert-butylaniline, N,N-bis-(2-hydroxyethyl)-3,5-diisopropylaniline, N,N-bis-(2-hydroxyethyl)-3,5-di-tert-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, N,N-diethyl-p-toluidine, N, At least one of N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-tert-butylaniline, N,N-dimethyl-3,5-di-tert-butylaniline, 4-(N,N-dimethylamino)-ethyl benzoate, 4-(N,N-dimethylamino)-methyl benzoate, 4-(N,N-dimethylamino)-n-butoxyethyl benzoate, 4-(N,N-dimethylamino)-benzoic acid-2-(methacryloyloxy)-ethyl benzoate, 4-(N,N-dimethylamino)-benzophenone, and 4-(N,N-dimethylamino)-butyl benzoate.
9. The method for achieving anti-caking of acrylic resin powder according to claim 3, characterized in that: The amine ether compound is selected from at least one of bis(2-dimethylaminoethyl) ether and 2,2-dimorpholinyl diethyl ether.
10. The method for achieving anti-caking of acrylic resin powder according to claim 1, characterized in that: The amine compound is an alcoholamine compound.