Environment-friendly degradable fluoride-free oil-resistant and fat-resistant agent as well as preparation method and application thereof

Abstract

The invention belongs to the field of waterproof and oil-proof agent materials, and particularly relates to an environment-friendly degradable fluoride-free oil-resistant and fat-resistant agent as well as a preparation method and application thereof, and the environment-friendly degradable fluoride-free oil-resistant and fat-resistant agent is prepared from the following raw materials in parts by weight: 40-50 parts of biological wax, 4-6 parts of modified polyacrylate, 15-20 parts of rosin, 1-2 parts of shellac, 75-100 parts of filler and 150-190 parts of deionized water. The oil-resistant and fat-resistant agent prepared by the invention can effectively prevent grease and water from permeating, has good waterproof and oil-resistant effects, and has good degradability.

Description

Technical Field

[0001] The invention belongs to the field of water and oil proofing agent materials, and in particular relates to an environmentally friendly and degradable fluorine-free oil and grease proofing agent and a preparation method and application thereof. Background Art

[0002] Oil and grease repellent is an auxiliary agent used to prevent the surface of the substrate from being penetrated by grease. It is widely used in textiles, food packaging paper, non-woven fabrics, carpets and other fields. With the increasing awareness of health and environmental protection, the demand for oil-proof paper in daily paper is increasing, especially in food oil-proof packaging. Daily food packaging paper and pulp-molded disposable tableware are not only required to have oil and grease resistance, but also require the packaging materials to be degradable and not pollute the environment. Therefore, environmentally friendly biodegradable oil-proof products have been widely studied.

[0003] Patent CN110791957B discloses a biomass waterproof and oil-proof agent and a preparation method thereof, comprising: preparing an acrylic emulsion; preparing a biomass adhesive using an adhesive and a biomass emulsifier; adding biomass powder to the acrylic emulsion, stirring to obtain a first mixed solution; adding the first mixed solution to the biomass adhesive; adjusting the pH, stirring to obtain a biomass waterproof and oil-proof agent. The biomass waterproof and oil-proof agent has both anti-ultraviolet and waterproof and oil-proof functions, and can be widely used in various products such as textiles, resin materials, foam products, and building boards. Patent CN110777566B discloses a degradable waterproof and oil-proof coating on food packaging paper, which is composed of modified chitosan, montmorillonite, and fluorosilicone organic matter; the modified chitosan is carboxymethyl chitosan; the montmorillonite is combined with the fluorosilicone organic matter to form a hydrophobic surface layer; the weight ratio of the modified chitosan, montmorillonite, and fluorosilicone organic matter is (5-10): (5-10): 1; the food packaging paper formed by coating the base paper of the present invention has the characteristics of environmental protection. The above inventions all use fluorine-containing compounds, which have certain biological toxicity and may cause damage to the human body if used for a long time.

[0004] Therefore, there is an urgent need for an environmentally friendly, biodegradable, and fluorine-free anti-oil and anti-grease agent on the market. Summary of the invention

[0005] In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides an anti-oil and anti-grease agent, which has good water and oil proof effects and good degradability.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] The first aspect of the present invention provides an environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent, which comprises the following raw materials, by weight: 40-50 parts of biowax, 4-6 parts of modified polyacrylate, 15-20 parts of rosin, 1-2 parts of shellac, 75-100 parts of filler, and 150-190 parts of deionized water.

[0008] In some embodiments, the biowax is palm wax or beeswax.

[0009] In some embodiments, the method for preparing the modified polyacrylate comprises the following steps:

[0010] (1) adding carboxymethyl chitosan and triethylamine to dichloromethane, adding maleic anhydride while stirring at room temperature, reacting at 40-50° C. for 4-5 hours, filtering, washing, and drying to obtain amidated chitosan;

[0011] (2) Add the amidated chitosan obtained in step (1) into water, raise the temperature to 55-65° C., add potassium persulfate and stir for 25-35 min, then add acrylate while stirring, continue the reaction for 6-7 h, extract, concentrate and dry to obtain modified polyacrylate.

[0012] Preferably, the acrylic acid ester is 2-carboxyethyl acrylate, methyl methacrylate and hydroxyethyl methacrylate, and the mass ratio of the three is (0.2-0.5):1:(0.3-0.7).

[0013] Polyacrylate has certain degradability, low surface energy, and certain oil resistance, and can be used as a component of an anti-oil and anti-fat agent. When used in products that need to be folded, such as food packaging paper, polyacrylate is prone to wrinkling and may crack during the folding process, which affects the oil resistance. The present invention introduces double bonds by reacting the amino group of carboxymethyl chitosan with maleic anhydride, and introduces carboxymethyl chitosan into polyacrylate, thereby increasing the oil resistance and degradability of the anti-oil and anti-fat agent. The possible reason is that carboxymethyl chitosan increases the degradability of polyacrylate, and the double bonds introduced by the reaction of the evenly distributed amino groups on the carboxymethyl chitosan structure with maleic anhydride react with acrylate to increase the crosslinking degree of polyacrylate, increase the compactness of polyacrylate, and improve the oil resistance effect. In addition, the introduction of a certain number of amide groups further reduces the surface energy, and can prevent oil droplets from adhering to the surface and prevent grease penetration.

[0014] In some embodiments, the mass ratio of the carboxymethyl chitosan to maleic anhydride is 1:(0.4-0.7).

[0015] In some embodiments, the mass ratio of the amidated chitosan to the acrylate in step (2) is (0.2-0.6):1.

[0016] The invention limits the mass ratio of carboxymethyl chitosan to maleic anhydride so that amino groups on the surface of carboxymethyl chitosan react with maleic anhydride to introduce amide groups and double bonds, while not reducing the film-forming property and adhesion to the substrate of the carboxymethyl chitosan. The mass ratio of amidated chitosan to acrylamide is further limited so that the cross-linking degree of polyacrylamide is increased, while being less prone to cracking and having increased oil resistance and applicability.

[0017] In some embodiments, the filler is nanocellulose and modified starch, and the mass ratio of the two is 1:(11-15).

[0018] In some embodiments, the method for preparing the modified starch comprises the following steps: adding starch and a silane coupling agent to ethanol, stirring at 50-60° C. for 5-6 hours, then adding azobisisobutyronitrile and allyl epoxy-terminated polyether, reacting at 70-80° C. for 1-2 hours, filtering, washing, and drying to obtain the modified starch.

[0019] Preferably, the silane coupling agents are KH570 and KH550, and the mass ratio of the two is 1:(0.2-0.6).

[0020] Although starch has carboxyl, ester, amide and other functional groups, which have strong interaction with the substrate and can fill the gaps between the substrates to prevent oil and fat penetration, it also has strong affinity with water molecules, which reduces the water resistance of the oil and grease resistant agent. The present invention introduces amino groups and double bonds on the starch surface by selecting a specific ratio and type of silane coupling agent, and then reacts with allyl epoxy-terminated polyether to obtain modified starch, which increases the water resistance and oil resistance of the oil and grease resistant agent and has good degradability. The possible reason is that the amino groups and double bonds of the silane coupling agent are cross-linked with the double bonds and epoxy groups of the allyl epoxy-terminated polyether, which increases the water resistance of the starch. In addition, the addition of the polyether improves the dispersibility of the starch in the system, and the polyether has good affinity with the substrate, which increases the adhesion of the oil and grease resistant agent and improves the oil and grease resistance.

[0021] In some embodiments, the mass ratio of the starch to the silane coupling agent is 1:(0.5-0.8).

[0022] In some embodiments, the mass ratio of the silane coupling agent to the allyl epoxy-terminated polyether is 1:(1-1.5).

[0023] The present invention grafts amino groups and double bonds on the surface of starch by limiting the mass ratio of starch and silane coupling agent, while not affecting the adhesion of starch to a substrate. By limiting the mass ratio of silane coupling agent and allyl epoxy group-terminated polyether, the starch reacted with the silane coupling agent can fully react with the allyl epoxy group-terminated polyether, thereby increasing the crosslinking degree and improving the oil and stain resistance.

[0024] The second aspect of the present invention provides a method for preparing an environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent, comprising the following steps: heating biowax, rosin and shellac to 60-70°C, adding part of deionized water, and then adding modified polyacrylate, stirring at 70-80°C and 40-60rpm for 5-6h, and then adding filler and the remaining deionized water at room temperature and stirring at 800-1000rpm for 2-4min to obtain the product.

[0025] The third aspect of the present invention provides an environmentally friendly and degradable fluorine-free anti-oil and anti-grease agent for use in food packaging and pulp molded tableware.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The present invention obtains a green and environmentally friendly anti-oil and anti-grease agent by modifying polyacrylate and combining it with other bio-based materials. The agent has good barrier properties and degradability, and has good oil and water repellency effects.

[0028] 2. The present invention introduces double bonds by reacting amino groups of carboxymethyl chitosan with maleic anhydride to introduce carboxymethyl chitosan into polyacrylate. Carboxymethyl chitosan increases the degradability of polyacrylate. The double bonds introduced by the reaction of amino groups uniformly distributed on the carboxymethyl chitosan structure with maleic anhydride react with acrylate to increase the crosslinking degree of polyacrylate, increase the compactness of polyacrylate, and enhance the oil-proof effect. In addition, the introduction of a certain number of amide groups further reduces the surface energy, and can prevent oil droplets from adhering to the surface and prevent grease penetration.

[0029] 3. The present invention introduces amino groups and double bonds on the surface of starch by selecting a silane coupling agent of a specific ratio and type, and then reacts with the allyl epoxy-terminated polyether. The amino groups and double bonds of the silane coupling agent are cross-linked with the double bonds and epoxy groups of the allyl epoxy-terminated polyether, thereby increasing the water resistance of the starch. In addition, the addition of the polyether improves the dispersibility of the starch in the system, and the polyether has good affinity with the substrate, thereby increasing the adhesion of the oil and grease resistance agent and improving the oil and grease resistance. DETAILED DESCRIPTION

[0030] The present invention will be described below in conjunction with specific embodiments. It should be noted that the following examples and comparative examples are only used to illustrate the present invention and are not intended to limit the present invention. Other combinations and various modifications within the concept of the present invention may be performed without departing from the spirit or scope of the present invention.

[0031] In order to facilitate those skilled in the art to implement the present invention, some raw materials and manufacturers of the embodiments and comparative examples are described as follows:

[0032] The compounds and related reagents used in the following examples and comparative examples can all be purchased from the market, among which beeswax of food grade was purchased from Cangzhou Fengzhiyi Wax Co., Ltd.; allyl epoxy-terminated polyether model KL-11B was purchased from Liaoning Kelong Fine Chemical Co., Ltd.; starch was food-grade corn starch purchased from Shanghai Dongzhen Trading Co., Ltd.; rosin was food-grade purchased from Henan Wanshan New Materials Technology Co., Ltd.; shellac was food-grade shellac purchased from Hubei Yihang Biotechnology Co., Ltd.; nanocellulose was plant-based with a particle size of 20 nm purchased from Wuhan Kemik Biomedical Technology Co., Ltd.; base paper for cups was purchased from Shenzhen Hansong Paper Co., Ltd., trade name: FAB350, basis weight: 350g / m 2 .

[0033] Preparation Example 1

[0034] The preparation method of modified polyacrylate-1 comprises the following steps:

[0035] (1) 10 g of carboxymethyl chitosan and 6 g of triethylamine were added to 200 ml of dichloromethane, and 6 g of maleic anhydride was added while stirring at room temperature, and the mixture was reacted at 45° C. for 4.5 h, and the mixture was filtered, washed, and dried to obtain amidated chitosan;

[0036] (2) adding 4 g of the amidated chitosan obtained in step (1) to 100 ml of deionized water, heating to 60° C., adding 0.1 g of potassium persulfate and stirring for 30 min, then adding 10 g of acrylate while stirring, continuing the reaction for 6.5 h, extracting, concentrating, and drying to obtain modified polyacrylate-1;

[0037] The acrylate is 2-carboxyethyl acrylate, methyl methacrylate and hydroxyethyl methacrylate, and the mass ratio of the three is 0.3:1:0.5.

[0038] Preparation Example 2

[0039] The preparation method of modified polyacrylate-2 is the same as that of Preparation Example 1, except that the amount of maleic anhydride added is 10 g.

[0040] Preparation Example 3

[0041] The preparation method of modified polyacrylate-3 is the same as that of Preparation Example 1, except that the amount of amidated chitosan added is 9 g.

[0042] Preparation Example 4

[0043] The preparation method of polyacrylate comprises the following steps: heating 10g of acrylate to 60°C, adding 0.1g of potassium persulfate, stirring for 30min, and drying to obtain polyacrylate;

[0044] The acrylate is 2-carboxyethyl acrylate, methyl methacrylate and hydroxyethyl methacrylate, and the mass ratio of the three is 0.3:1:0.5.

[0045] Preparation Example 5

[0046] The preparation method of modified starch-1 comprises the following steps: adding 10g corn starch and 7.5g silane coupling agent into 200ml anhydrous ethanol, stirring at 55°C for 5.5h, then adding 0.1g azobisisobutyronitrile and 9g allyl epoxy-terminated polyether, reacting at 75°C for 1.5h, filtering, washing, and drying to obtain modified starch-1;

[0047] The silane coupling agents are KH570 and KH550, and the mass ratio of the two is 1:4.

[0048] Preparation Example 6

[0049] The preparation method of modified starch-2 is the same as that of Preparation Example 4, except that the amount of silane coupling agent added is 10 g.

[0050] Preparation Example 7

[0051] The preparation method of modified starch-3 is the same as that of Preparation Example 4, except that the amount of allyl epoxy-terminated polyether added is 13.5 g.

[0052] Example 1

[0053] An environmentally friendly, biodegradable, fluorine-free, oil- and grease-resistant agent, comprising the following raw materials, by weight: 45 parts of beeswax, 15 parts of modified polyacrylate, 18 parts of rosin, 1.5 parts of shellac, 90 parts of filler, and 170 parts of deionized water;

[0054] Among them, the filler is nanocellulose and modified starch-1, and the mass ratio of the two is 1:13.

[0055] The preparation method of the environmentally friendly and biodegradable fluorine-free anti-oil and anti-grease agent in this embodiment comprises the following steps: heating beeswax, rosin and shellac to 65°C, adding half amount of deionized water, and then adding modified polyacrylate-1, stirring at 75°C and 50rpm for 5.5h, and then adding filler and the remaining deionized water at room temperature and stirring at 900rpm for 3min to obtain the product.

[0056] Example 2

[0057] An environmentally friendly, biodegradable, fluorine-free, oil- and grease-resistant agent, comprising the following raw materials, by weight: 40 parts of beeswax, 14 parts of modified polyacrylate, 15 parts of rosin, 1 part of shellac, 75 parts of filler, and 150 parts of deionized water;

[0058] Among them, the filler is nanocellulose and modified starch-1, and the mass ratio of the two is 1:11.

[0059] The preparation method of the environmentally friendly and biodegradable fluorine-free anti-oil and anti-grease agent in this embodiment comprises the following steps: heating beeswax, rosin and shellac to 60°C, adding half amount of deionized water, and then adding modified polyacrylate-1, stirring at 70°C and 40rpm for 6h, and then adding filler and the remaining deionized water at room temperature and stirring at 800rpm for 4min to obtain the product.

[0060] Example 3

[0061] An environmentally friendly, biodegradable, fluorine-free, oil- and grease-resistant agent, comprising the following raw materials, by weight: 50 parts of beeswax, 16 parts of modified polyacrylate, 20 parts of rosin, 2 parts of shellac, 100 parts of filler, and 190 parts of deionized water;

[0062] Among them, the filler is nanocellulose and modified starch-1, and the mass ratio of the two is 1:15.

[0063] The preparation method of the environmentally friendly and biodegradable fluorine-free anti-oil and anti-grease agent in this embodiment comprises the following steps: heating beeswax, rosin and shellac to 70°C, adding half amount of deionized water, then adding modified polyacrylate-1, stirring at 80°C and 60rpm for 5h, then adding filler and the remaining deionized water at room temperature and stirring at 1000rpm for 2min.

[0064] Example 4

[0065] An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that an equal amount of modified polyacrylate-1 is replaced by modified polyacrylate-2.

[0066] Example 5

[0067] An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that an equal amount of modified polyacrylate-1 is replaced by modified polyacrylate-3.

[0068] Example 6

[0069] An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that an equal amount of modified starch-1 is replaced by modified starch-2.

[0070] Example 7

[0071] An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that an equal amount of modified starch-1 is replaced by modified starch-3.

[0072] Example 8

[0073] An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that an equal amount of modified starch-1 is replaced by corn starch.

[0074] Comparative Example 1

[0075] An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that an equal amount of modified polyacrylate-1 is replaced by polyacrylate.

[0076] Performance Testing

[0077] The oil and grease resistant agent obtained in the above examples and comparative examples was applied to one side of the base paper for cups, with a coating amount of 9 g / m 2 .

[0078] 1. Oil resistance

[0079] Reference TAPPI T559cm-02.

[0080] 2. Waterproof

[0081] Refer to standard Cobb Size TAPPI T441.

[0082] 3. Degradability

[0083] Biodegradability at six months was recorded according to standard EN 13432.

[0084] The test results are shown in Table 1.

[0085] Table 1

[0086]

[0087] By comparing the experimental data of Examples 1-3 in Table 1, it can be seen that the anti-oil and anti-fat agent has good water-proof and oil-proof properties and degradability; by comparing Example 4 with Example 1, it can be seen that the change in the ratio of carboxymethyl chitosan and maleic anhydride may lead to a decrease in film-forming property and adhesion to the substrate, and a decrease in oil and water resistance; by comparing Example 5 with Example 1, it can be seen that the change in the ratio of amidated chitosan and acrylate may lead to an increase in the degree of crosslinking and a decrease in degradability; by comparing Example 6 with Example 1, it can be seen that the change in the ratio of starch and silane coupling agent may lead to a decrease in the adhesion of starch to the substrate and water-proof and oil-proof properties; by comparing Example 7 with Example 1, it can be seen that the change in the ratio of silane coupling agent and allyl epoxy-terminated polyether may lead to excessive polymerization and a decrease in degradability; by comparing Example 8 with Example 1, it can be seen that the water resistance of the anti-oil and anti-fat agent is reduced by directly using starch; by comparing Comparative Example 1 with Example 1, it can be seen that the use of unmodified polyacrylate reduces the oil resistance and water resistance of the anti-oil and anti-fat agent.

[0088] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. An environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent, characterized in that: The invention comprises the following raw materials in parts by weight: 40-50 parts of bio-wax, 4-6 parts of modified polyacrylate, 15-20 parts of rosin, 1-2 parts of shellac, 75-100 parts of filler and 150-190 parts of deionized water.

2. The environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent according to claim 1, characterized in that: The preparation method of the modified polyacrylate comprises the following steps: (1) adding carboxymethyl chitosan and triethylamine to dichloromethane, adding maleic anhydride while stirring at room temperature, reacting at 40-50° C. for 4-5 hours, filtering, washing, and drying to obtain amidated chitosan; (2) Add the amidated chitosan obtained in step (1) into water, raise the temperature to 55-65° C., add potassium persulfate and stir for 25-35 min, then add acrylate while stirring, continue the reaction for 6-7 h, extract, concentrate and dry to obtain modified polyacrylate.

3. The environmentally friendly, degradable, fluorine-free anti-oil and anti-grease agent according to claim 2, characterized in that: The mass ratio of the carboxymethyl chitosan to maleic anhydride is 1:(0.4-0.7).

4. The environmentally friendly, degradable, fluorine-free anti-oil and anti-grease agent according to claim 2, characterized in that: The mass ratio of the amidated chitosan to the acrylate in step (2) is (0.2-0.6):

1.

5. The environmentally friendly, degradable, fluorine-free anti-oil and anti-grease agent according to claim 1, characterized in that: The filler is nano cellulose and modified starch, and the mass ratio of the two is 1:(11-15).

6. The environmentally friendly, degradable, fluorine-free anti-oil and anti-grease agent according to claim 5, characterized in that: The preparation method of the modified starch comprises the following steps: adding starch and a silane coupling agent into ethanol, stirring at 50-60° C. for 5-6 hours, then adding azobisisobutyronitrile and allyl epoxy-terminated polyether, reacting at 70-80° C. for 1-2 hours, filtering, washing, and drying to obtain the modified starch.

7. The environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent according to claim 6, characterized in that: The mass ratio of the starch to the silane coupling agent is 1:(0.5-0.8).

8. The environmentally friendly, biodegradable, fluorine-free anti-oil and anti-grease agent according to claim 6, characterized in that: The mass ratio of the silane coupling agent to the allyl epoxy-terminated polyether is 1:(1-1.5).

9. A method for preparing the environmentally friendly and degradable fluorine-free oil and grease resistant agent according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: heating biowax, rosin and shellac to 60-70°C, adding part of deionized water, and then adding modified polyacrylate, stirring at 70-80°C and 40-60rpm for 5-6h, and then adding filler and the remaining deionized water at room temperature and stirring at 800-1000rpm for 2-4min to obtain the product.

10. Use of the environmentally friendly, degradable, fluorine-free oil and grease resistant agent according to any one of claims 1 to 8 or the environmentally friendly, degradable, fluorine-free oil and grease resistant agent obtained by the preparation method according to claim 9 in food packaging and pulp molded tableware.

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