Preparation method for oil-proofing agent based on polymerization of acrylic acid and organosilicon

Abstract

The present invention relates to the technical field of polymer synthesis and relates to a preparation method for an oil-proofing agent based on polymerization of acrylic acid and organosilicon. In the present invention, the method comprises: adding methyl acrylate, hydroxyethyl acrylate, dithiothreitol, m-trifluoromethylcinnamaldehyde, and triethylamine to a reaction kettle, and stirring and heating the mixture for a reaction; adding an initiator, and continuing the reaction, so that the acrylic monomers undergo a polymerization reaction to form a polymer having good stability and mobility; further adding α,ω-dihydroxypolydimethylsiloxane and continuing the reaction, so that the linear organosilicon and the polymer undergo a polymerization reaction; adding an emulsifier, and stirring and mixing the mixture for a reaction to obtain an oil-proofing agent; and adding the oil-proofing agent to a pulp for food boxes and uniformly stirring the mixture, so that the polymer is uniformly distributed on the surface of the pulp for food boxes to form a dense oil-proofing film, thereby effectively preventing the adhesion of oil stains. The oil-proofing agent prepared in the present invention has good oil-proofing performance, and can effectively prevent the adhesion of oil stains, thereby maintaining the cleanliness of food packaging and catering utensils.

Description

A method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon Technical Field

[0001] This invention relates to the field of polymer synthesis technology, and in particular to a method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon. Background Technology

[0002] In modern life, the cleanliness of food packaging and tableware is a major concern. Oil stains often adhere to food packaging and tableware, which not only affect appearance but can also pose hygiene and safety issues. Therefore, the use of oil-repellent agents has become increasingly widespread. Oil-repellent agents are chemical substances that reduce surface tension, thereby preventing oil stains from adhering.

[0003] Chinese Patent CN116623461A: Provides a fluorine-free oil-resistant agent for pulp food containers and catering utensils and its production process. The process involves adding an adhesive and 2-ethylhexyl acrylate to deionized water and stirring at a low speed of 60-70 rpm to obtain mixture A. The adhesive is one or more of hydroxypropyl methylcellulose, polyvinylpyrrolidone, polyacrylamide, and chitosan. Modified starch is added to deionized water and stirred at a low speed at 70-80℃ to obtain a modified starch solution. Emulsified paraffin wax and a filler are added to the modified starch solution. The filler is one or more of calcium carbonate, quartz powder, titanium dioxide, montmorillonite, and glass powder. The solution is then subjected to ultrasonic vibration to achieve uniform dispersion, resulting in mixture B. In use, mixture A is first stirred evenly with pulp, then mixture B is added and stirred continuously until uniform. Mixtures A and B serve as the fluorine-free oil-resistant agent.

[0004] Chinese Patent CN117626705A: Provides a fluorine-free oil repellent agent, its preparation method and application, wherein the fluorine-free oil repellent agent comprises the following raw materials in parts by weight: 2-5 parts of polyvinyl alcohol, 15-25 parts of barrier kaolin, 2-5 parts of oxidized polyethylene wax, 5-15 parts of octadecyl methacrylate, and 58-60 parts of deionized water.

[0005] Chinese Patent CN118930761A: Provides a fluorinated oil repellent and its preparation method, comprising the following raw materials in parts by weight: fluorinated monomer: 60-70 parts by weight; acrylate monomer: 10-15 parts by weight; composite crosslinking monomer: 3-6 parts by weight; solvent: 100-150 parts by weight; initiator: 0.3-0.5 parts by weight; molecular weight regulator: 0.01-0.03 parts by weight; neutralizer: 1-3% (based on emulsion weight); antifreeze: 3-5 parts by weight; hydrophilic monomer: 5-15 parts by weight; retention aid: 4-6 parts by weight; antibacterial monomer: 5-10 parts by weight; coating material monomer: 15-25 parts by weight.

[0006] The oil-repellent agents prepared by the above patents and existing technologies are mainly divided into two categories: inorganic oil-repellent agents and organic oil-repellent agents. Inorganic oil-repellent agents mainly utilize nanomaterials, such as nano-silica and nano-alumina, to achieve the oil-repellent effect. Organic oil-repellent agents are mainly prepared from some polymeric materials, such as polytetrafluoroethylene and polyvinylidene fluoride. In addition, some oil-repellent agents are prepared by combining inorganic and organic materials.

[0007] While existing oil-repellent agents can address the oil-proofing issues of food packaging and tableware to some extent, several problems remain. First, inorganic oil-repellent agents suffer from migration and stability issues, potentially migrating from material surfaces after prolonged use and causing food contamination. Second, the preparation processes for inorganic oil-repellent agents are complex and costly. While organic oil-repellent agents offer better stability, their preparation may involve the use of harmful chemicals such as Freon, posing threats to the environment and human health. Summary of the Invention

[0008] To address the above problems, this invention provides a method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon, the operation steps of which are as follows:

[0009] S1: According to the weight parts, add 12-18 parts of methyl acrylate, 10-16 parts of hydroxyethyl acrylate, 3-6 parts of dithiothreitol (CAS No. 27565-41-9), 0.2-0.5 parts of m-trifluoromethylcinnamaldehyde (CAS No. 871543-59-8), and 2-4 parts of triethylamine to the reaction vessel, stir and heat to react;

[0010] S2: Add 0.05-0.2 parts of initiator and continue the reaction for 90-120 minutes; allow the acrylic monomer to polymerize and form a polymer.

[0011] S3: Continue to add 28-36 parts of α,ω-dihydroxypolydimethylsiloxane and continue the reaction to allow the linear organosilicon to polymerize with the polymer;

[0012] S4: Add 60-80 parts of emulsifier, stir and mix to react, and obtain the oil-resistant agent.

[0013] The reaction temperature of S1 is 60-70℃, and the reaction time is 90-120 min.

[0014] The initiator is one of azobisisobutyronitrile, dimethyl azobisisobutyrate, azoisobutylcyanoformamide, and azobisisobutylamidine.

[0015] The reaction temperature of S3 is 70-80℃, and the reaction time is 150-180 min.

[0016] The emulsifier is one of alkylphenyl ether polyoxyethylene ether, fatty alcohol polyoxyethylene ether, PEG-7 glyceryl cocoate, sodium stearate, and sodium dodecyl sulfate.

[0017] The reaction temperature of S4 is 50-60℃, and the reaction time is 40-60 min.

[0018] The present invention also provides the above-mentioned oil repellent prepared based on the polymerization of acrylic acid and organosilicon.

[0019] The present invention also provides the use of an oil-resistant agent in the preparation of pulp, wherein the amount of oil-resistant agent added is 0.5-1% of the pulp mass.

[0020] Reaction mechanism

[0021] The reaction mechanism between the propenyl groups of methyl acrylate and hydroxyethyl acrylate and the thiol groups of dithiothreitol is mainly through a thiol-propenyl addition reaction. Specifically, the thiol group (-SH) can attack the propenyl group (-CH=CH2) under appropriate conditions to form a new carbon-sulfur bond.

[0022] The alkene of m-trifluoromethylcinnamaldehyde also follows a similar thiol-propenyl addition reaction mechanism with the thiol group of dithiothreitol. In this reaction, the alkene double bond of m-trifluoromethylcinnamaldehyde acts as a nucleophile, undergoing an addition reaction with the thiol group of dithiothreitol to form a new carbon-sulfur bond.

[0023] Next, through click chemistry polymerization, these monomer and polymer segments can be further linked together to form polymers with good stability and mobility. Click chemistry is a highly efficient chemical reaction that can rapidly and accurately link two molecular fragments under mild conditions with very few byproducts.

[0024] Finally, the linear organosilicon reacts with the polymer, further enhancing the polymer's oil repellency. Organosilicon possesses excellent hydrophobic and oleophobic properties; therefore, its introduction into polymers can significantly improve their resistance to oily substances.

[0025] Technical effect

[0026] The mechanisms by which compounds such as m-trifluoromethylcinnamaldehyde and dithiothreitol improve the oil resistance of polymers can be analyzed from the following aspects:

[0027] 1. The fluorine atom in m-trifluoromethylcinnamaldehyde has high electronegativity, which enables it to form stronger interactions with other molecules in the polymer, thereby improving the polymer's stability and oil resistance. It also helps reduce the adsorption and penetration of oils onto the polymer surface.

[0028] 2. Introducing monomers such as m-trifluoromethylcinnamaldehyde and dithiothreitol into the polymer allows for the formation of a more compact cross-linked network structure through click polymerization. This compact cross-linked network structure helps improve the polymer's oil resistance.

[0029] 3. The introduction of compounds such as m-trifluoromethylcinnamaldehyde and dithiothreitol reduces the surface energy of the polymer. Materials with low surface energy are less susceptible to wetting and penetration by oils, thus improving the polymer's oil resistance. Detailed Implementation

[0030] To further illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description is provided in conjunction with embodiments and comparative examples:

[0031] Waterproof and oil-proof test: The lunch box was filled with 100℃ hot water and 150℃ cooking oil respectively, and the temperature was kept constant for 24 hours. The test results are shown in Table 1.

[0032] Hot water permeability test: The sample is tested according to the requirements of GB / T 36787—2018. The sample is bent into a bowl shape and placed on a plate lined with filter paper. Hot water at (95±5)℃ is poured into the sample and left to stand for 30 minutes. Observe whether the sample is deformed and whether there is any seepage or leakage on the back of the sample. Water vapor condensation at the bottom caused by the temperature difference between the inside and outside of the sample is not considered seepage or leakage.

[0033] To ensure quality, this invention uses 100℃ hot water to maintain a constant temperature for 24 hours for testing.

[0034] Hot oil permeability test: The sample was tested according to the requirements of GB / T 36787—2018. The sample was bent into a bowl shape and placed on a plate lined with filter paper. Hot oil at (95±5)℃ was poured into the sample and left to stand for 30 minutes. The sample was observed to see if it was deformed and whether oil marks appeared on the back of the sample.

[0035] To ensure quality, this invention uses edible oil at 150℃ and maintains the temperature for 24 hours for testing.

[0036] These experimental food containers measure 22 x 19 x 3.5 cm and are divided into 3 compartments.

[0037] Example 1

[0038] A method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon, comprising the following steps:

[0039] S1: Add 12g of methyl acrylate, 10g of hydroxyethyl acrylate, 3g of dithiothreitol (CAS No. 27565-41-9), 0.2g of m-trifluoromethylcinnamaldehyde (CAS No. 871543-59-8), and 2g of triethylamine to a reaction vessel, stir and heat to react.

[0040] S2: Add 0.05g of initiator and continue the reaction for 90min; to allow the acrylic monomer to undergo a polymerization reaction;

[0041] S3: Continue to add 28g of α,ω-dihydroxypolydimethylsiloxane and continue the reaction to allow the linear organosilicon to polymerize with the polymer.

[0042] S4: Add 60g of emulsifier, stir and mix to react, and obtain an oil-resistant agent;

[0043] S5: Add 0.5 kg of the oil-repellent agent prepared in S4 to 100 kg of lunch box pulp and stir evenly so that the polymer is evenly distributed on the surface of the lunch box pulp, forming a dense oil-repellent film that effectively prevents oil stains from adhering.

[0044] The reaction temperature of S1 is 60℃ and the reaction time is 90 min.

[0045] The initiator is azobisisobutyronitrile.

[0046] The reaction temperature of S3 is 70℃ and the reaction time is 150 min.

[0047] The emulsifier is an alkylphenyl ether polyoxyethylene ether.

[0048] The reaction temperature of S4 is 50℃ and the reaction time is 40 min.

[0049] Example 2

[0050] A method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon, comprising the following steps:

[0051] S1: Add 14g of methyl acrylate, 12g of hydroxyethyl acrylate, 4g of dithiothreitol (CAS No. 27565-41-9), 0.3g of m-trifluoromethylcinnamaldehyde (CAS No. 871543-59-8), and 3g of triethylamine to a reaction vessel, stir and heat to react.

[0052] S2: Add 0.1g of initiator and continue the reaction for 100min; to allow the acrylic monomer to undergo a polymerization reaction;

[0053] S3: Continue to add 32g of α,ω-dihydroxypolydimethylsiloxane and continue the reaction to allow the linear organosilicon to polymerize with the polymer.

[0054] S4: Add 65g of emulsifier, stir and mix to react, and obtain an oil-resistant agent;

[0055] S5: Add 0.6 kg of the oil-repellent agent prepared in S4 to 100 kg of lunch box pulp and stir evenly so that the polymer is evenly distributed on the surface of the lunch box pulp, forming a dense oil-repellent film that effectively prevents oil stains from adhering.

[0056] The reaction temperature of S1 is 65℃ and the reaction time is 100 min.

[0057] The initiator is dimethyl azobisisobutyrate.

[0058] The reaction temperature of S3 is 75℃ and the reaction time is 160 min.

[0059] The emulsifier is fatty alcohol polyoxyethylene ether.

[0060] The reaction temperature of S4 is 55℃ and the reaction time is 45 min.

[0061] Example 3

[0062] A method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon, comprising the following steps:

[0063] S1: Add 16g of methyl acrylate, 14g of hydroxyethyl acrylate, 5g of dithiothreitol (CAS No. 27565-41-9), 0.4g of m-trifluoromethylcinnamaldehyde (CAS No. 871543-59-8), and 3g of triethylamine to a reaction vessel, stir and heat to react.

[0064] S2: Add 0.15g of initiator and continue the reaction for 110min; to allow the acrylic monomer to undergo a polymerization reaction;

[0065] S3: Continue to add 34g of α,ω-dihydroxypolydimethylsiloxane and continue the reaction to allow the linear organosilicon to polymerize with the polymer.

[0066] S4: Add 75g of emulsifier, stir and mix to react, and obtain an oil-resistant agent;

[0067] S5: Add 0.8 kg of the oil-repellent agent prepared in S4 to 100 kg of lunch box pulp and stir evenly so that the polymer is evenly distributed on the surface of the lunch box pulp, forming a dense oil-repellent film that effectively prevents oil stains from adhering.

[0068] The reaction temperature of S1 is 65℃ and the reaction time is 110 min.

[0069] The initiator is azoisobutyl cyanoformamide.

[0070] The reaction temperature of S3 is 75℃ and the reaction time is 170 min.

[0071] The emulsifier is PEG-7 glyceryl cocoate.

[0072] The reaction temperature of S4 is 55℃ and the reaction time is 55min.

[0073] Example 4

[0074] A method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon, comprising the following steps:

[0075] S1: Add 18g of methyl acrylate, 16g of hydroxyethyl acrylate, 6g of dithiothreitol (CAS No. 27565-41-9), 0.5g of m-trifluoromethylcinnamaldehyde (CAS No. 871543-59-8), and 4g of triethylamine to a reaction vessel, stir and heat to react.

[0076] S2: Add 0.2g of initiator and continue the reaction for 120min; this allows the acrylic monomers to polymerize, forming a polymer with good stability and migration.

[0077] S3: Continue to add 36g of α,ω-dihydroxypolydimethylsiloxane and continue the reaction to allow the linear organosilicon to polymerize with the polymer;

[0078] S4: Add 80g of emulsifier, stir and mix to react, and obtain an oil-resistant agent;

[0079] S5: Add 1 kg of the oil-repellent agent prepared in S4 to 100 kg of lunch box pulp and stir evenly so that the polymer is evenly distributed on the surface of the lunch box pulp, forming a dense oil-repellent film that effectively prevents oil stains from adhering.

[0080] The reaction temperature of S1 is 70℃ and the reaction time is 120 min.

[0081] The initiator is azobisisobutylamidine.

[0082] The reaction temperature of S3 is 80℃ and the reaction time is 180 min.

[0083] The emulsifier is sodium dodecyl sulfate.

[0084] The reaction temperature of S4 is 60℃ and the reaction time is 60min.

[0085] Comparative Example 1

[0086] Dithiothreitol and m-trifluoromethylcinnamaldehyde were not added; otherwise, the same as in Example 1 was used.

[0087] Comparative Example 2

[0088] Dithiothreitol was not added; otherwise, it was the same as in Example 1.

[0089] Comparative Example 3

[0090] Without adding m-trifluoromethylcinnamaldehyde, otherwise the same as in Example 1.

[0091] Table 1

[0092] Through the analysis and comparison of the above embodiments and comparative examples, the oil repellent prepared by the present invention has good oil repellent properties, can effectively prevent oil stains from adhering, keep food packaging and tableware clean, and improve the user experience.

[0093] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon, comprising the following steps: S1: According to the weight parts, add 12-18 parts of methyl acrylate, 10-16 parts of hydroxyethyl acrylate, 3-6 parts of dithiothreitol, 0.2-0.5 parts of m-trifluoromethylcinnamaldehyde, and 2-4 parts of triethylamine into the reaction vessel, stir and heat to react; S2: Add 0.05-0.2 parts of initiator and continue the reaction for 90-120 minutes; allow the acrylic monomer to polymerize and form a polymer. S3: Continue to add 28-36 parts of α,ω-dihydroxypolydimethylsiloxane and continue the reaction to allow the linear organosilicon to polymerize with the polymer; S4: Add 60-80 parts of emulsifier, stir and mix to react, and obtain the oil-resistant agent.

2. The method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon according to claim 1, characterized in that: The reaction temperature of S1 is 60-70℃, and the reaction time is 90-120 min.

3. The method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon according to claim 1, characterized in that: The initiator is one of azobisisobutyronitrile, dimethyl azobisisobutyrate, azoisobutylcyanoformamide, and azobisisobutylamidine.

4. The method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon according to claim 1, characterized in that: The reaction temperature of S3 is 70-80℃, and the reaction time is 150-180 min.

5. The method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon according to claim 1, characterized in that: The emulsifier is one of alkylphenyl ether polyoxyethylene ether, fatty alcohol polyoxyethylene ether, fatty acid glyceride polyoxyethylene ether, sodium stearate, and sodium dodecyl sulfate.

6. The method for preparing an oil repellent based on the polymerization of acrylic acid and organosilicon according to claim 1, characterized in that: The reaction temperature of S4 is 50-60℃, and the reaction time is 40-60 min.

7. An oil repellent, characterized in that: The oil repellent is prepared by any one of the preparation methods of the oil repellent based on the polymerization of acrylic acid and organosilicon as described in claims 1 to 6.

8. The use of the oil-resistant agent according to claim 7 in the preparation of pulp, characterized in that, The amount of the oil-resistant agent added is 0.5-1% of the pulp mass.

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