A fluorine-containing rheological agent and its preparation method and application

Abstract

The present invention provides a fluorinated rheological agent, its preparation method, and application. The agent has the structure shown in Formula I below. The preparation method comprises reacting 1.0g of a PAMAM dendrimer with perfluoroalkylsulfonyl fluoride to produce the fluorinated rheological agent. The fluorinated rheological agent has four perfluorohexylsulfonyl fluoride groups and a high molecular weight. During material extrusion, it is less susceptible to migration loss, effectively eliminates periodic melt fracture, lowers the melt temperature during the processing of high-viscosity, high-molecular-weight resins, reduces die pressure, reduces screw torque, increases output, and improves extrusion efficiency. #imgabs0#

Description

Technical Field

[0001] The present invention relates to the technical field of polymer additives, and in particular to a fluorine-containing rheological agent and a preparation method and application thereof. Background Art

[0002] High-density polyethylene (HDPE) is a highly crystalline, non-polar thermoplastic resin polymerized from ethylene monomer. Due to its excellent heat resistance, durability, chemical stability, plasticity, and odorlessness, it is widely used in packaging, pipes, cables, and other applications. However, polyethylene typically has relatively low melt strength—a rapid drop in melt strength above its melting point—and extremely high melt viscosity, limiting its processing and application. Rheological agents, as additives in modern coatings processing, can improve and enhance the coating's rheological properties, coating stability, and application performance. Adding an appropriate amount of rheological agent during coating production can prevent filler and pigment precipitation during storage and splashing and dripping during application. The technological development of rheological agents primarily focuses on improving the product's inherent performance while ensuring safety and convenience, thereby enhancing the coating's performance during use. Secondly, the development of new types of rheological agents is crucial to meeting the evolving demands for high-performance coatings in modern processing. Rheological agents have an important influence on the processing of coatings, and more and more research and attention are being paid to them.

[0003] Fluorinated rheological agents play a crucial role in the processing of certain high-viscosity, high-molecular-weight materials. Whether acting as modifiers or surfactants, they play a crucial role in the processing of macromolecules. In resin processing, fluorinated rheological agents act both as internal modifiers and external lubricants, significantly impacting both internal and external aspects of the process. Internally, they can effectively reduce extrusion torque during melt extrusion, improving extrusion efficiency and melt pressure, and reducing production resistance. Externally, they effectively address melt fracture, improving the appearance of the melt and the mechanical and optical properties of the film. As a surface lubricant, they form a lubricating film at the interface between the die and the melt, thereby exerting their lubricating properties. Furthermore, fluorinated rheological agents can serve as alternatives to many processing aids and are used in the processing of high-viscosity and high-molecular-weight polyolefin resins, such as poly-α-methylstyrene and siloxane polymers.

[0004] CN107586389A synthesizes a binary fluoropolymer, then irradiates the binary fluoropolymer and a grafting monomer in a solution for surface grafting modification by high-energy radiation. The resulting mixture is washed, filtered, dried, and then pelletized to produce surface-modified fluorinated rheological agent microparticles specifically for polyethylene pipe resin processing. The composition comprises 65-85% by weight of vinylidene fluoride and 15-35% by weight of hexafluoropropylene in a vinylidene fluoride / hexafluoropropylene copolymer; 60-80% by weight of vinylidene fluoride and 20-40% by weight of tetrafluoroethylene in a vinylidene fluoride / tetrafluoroethylene copolymer; and 50-80% by weight of tetrafluoroethylene and 20-50% by weight of hexafluoropropylene in a tetrafluoroethylene / hexafluoropropylene copolymer. The amount of grafting modification monomer is 1-6% by weight. New functional groups are introduced onto the surface of the fluorinated rheological agent to improve surface compatibility, lubricity, and metal adhesion. However, the reaction conditions are not mild enough, requiring the reaction to occur under high-energy radiation.

[0005] CN106543371A discloses a modified fluorinated rheological agent for pipe materials and its application. The modified fluorinated rheological agent is a product of a terpolymer of vinylidene fluoride, hexafluoropropylene and tetrafluoroethylene grafted with a polar monomer. Its structural formula is as follows:

[0006]

[0007] Graft is a polar monomer, and M is the molecular weight of the polar monomer. Taking 100n + 150p + 64m + Mq = 100, the values ​​of 100n range from 35-75, 150p range from 15-35, 64m range from 10-30, and Mq range from 1-5. The modified fluorinated rheological agent and PE100+ pipe resin are uniformly mixed in a mixer and melt-extruded in an extruder. This reduces extrusion torque, improves extrusion efficiency, and improves the rheological behavior of the PE100+ pipe resin during processing. This modified fluorinated rheological agent is a terpolymer of vinylidene fluoride, hexafluoropropylene, and tetrafluoroethylene grafted onto a polar monomer using an emulsion polymerization method, resulting in a relatively complex reaction process.

[0008] Therefore, further research on rheological agents for polyolefin resins is still needed in this field. Summary of the Invention

[0009] The present invention provides a fluorine-containing rheological agent and a preparation method and application thereof, so as to overcome the defects of the prior art such as poor improvement effect of rheological agents on the processing performance of polyolefin resins, harsh preparation conditions of the rheological agents, and complicated processes.

[0010] In order to achieve the above object, the present invention provides a fluorinated rheological agent having the following structure:

[0011]

[0012] Here, n is a positive integer from 1 to 6.

[0013] In order to achieve the above object, the present invention also provides a method for preparing a fluorinated rheological agent, comprising the following steps:

[0014] 1.0 g of PAMAM dendrimer was reacted with perfluoroalkylsulfonyl fluoride to obtain a fluorinated rheological agent;

[0015]

[0016] Here, n is a positive integer from 1 to 6.

[0017] The preparation method of the fluorinated rheological agent of the present invention comprises the following steps: the molar ratio of 1.0G PAMAM dendrimer to perfluoroalkylsulfonyl fluoride is 1:1-10, and the reaction temperature is 0-70°C.

[0018] In the preparation method of the fluorinated rheological agent of the present invention, the mixing temperature of 1.0G PAMAM dendrimer and perfluoroalkylsulfonyl fluoride is 0-5°C, and the reaction temperature is 0-70°C.

[0019] The preparation method of the fluorinated rheological agent of the present invention, wherein the preparation method of the 1.0G PAMAM dendrimer comprises:

[0020] Step a, reacting an alkyl diamine compound with methyl acrylate to obtain 0.5G PAMAM dendrimer;

[0021]

[0022] Step b, 0.5 g of PAMAM dendrimer reacts with ethylenediamine to obtain 1.0 g of PAMAM dendrimer;

[0023]

[0024] The preparation method of the fluorinated rheological agent of the present invention comprises the following steps: in step a, the molar ratio of the alkyl diamine compound to methyl acrylate is 1:4-1:10, and the reaction temperature is 20-30°C; and in step b, the molar ratio of 0.5G PAMAM dendrimer to ethylenediamine is 1:20-1:30, and the reaction temperature is 20-30°C.

[0025] In the preparation method of the fluorinated rheological agent of the present invention, the solvent for the reaction of 1.0G PAMAM dendrimer and perfluoroalkylsulfonyl fluoride is N,N-dimethylformamide, and the reaction solvent is 3-4 times the total mass of the 1.0G PAMAM dendrimer and perfluoroalkylsulfonyl fluoride.

[0026] The preparation method of the fluorinated rheological agent of the present invention comprises the following steps: dropping the perfluoroalkylsulfonyl fluoride into a solution of 1.0G PAMAM dendrimers at a rate of 1-3 drops / min for mixing; and the reaction is carried out under an inert atmosphere.

[0027] In the preparation method of the fluorinated rheological agent of the present invention, the solvents for the reaction of the alkyldiamine compound with methyl acrylate and the reaction of 0.5G PAMAM dendrimer with ethylenediamine are alcohols.

[0028] In order to achieve the above object, the present invention further provides the use of the above fluorinated rheological agent in polyolefin materials.

[0029] Beneficial effects of the present invention:

[0030] (1) The fluorinated rheological agent of the present invention is prepared from an alkyl diamine compound, methyl acrylate and perfluorohexylsulfonyl fluoride through condensation reaction and amidation reaction. The reaction conditions are mild, the process is simple and the raw materials are easily available.

[0031] (2) The fluorinated rheological agent of the present invention has four perfluorohexylsulfonyl fluoride groups and a relatively high molecular weight. During material extrusion molding, migration loss is less likely to occur, effectively eliminating periodic melt fracture, lowering the melt temperature during the processing of high-viscosity, high-molecular-weight resins, reducing die pressure and screw torque, increasing output, and improving extrusion efficiency. The fluorinated rheological agent of the present invention is applied to polyethylene materials, significantly improving processing performance during extrusion and granulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 IR spectra of compounds b1, e1, and h1 of the present invention;

[0033] Figure 2 IR spectra of compounds c1, f1, and I1 of the present invention;

[0034] Figure 3 is the H NMR spectrum of compound c1 of the present invention;

[0035] Figure 4 This is a torque variation diagram of polyethylene with different contents of compound c1 of the present invention;

[0036] Figure 5 angular frequency-modulus-shear viscosity curve of polyethylene containing compound c1 (0%) of the present invention;

[0037] Figure 6 angular frequency-modulus-shear viscosity curve of polyethylene containing compound c1 (0.05%) of the present invention;

[0038] Figure 7angular frequency-modulus-shear viscosity curve of polyethylene containing compound c1 (0.1%) of the present invention;

[0039] Figure 8 Graph showing shear viscosity changes of polyethylene with different contents of compound c1 of the present invention;

[0040] Figure 9 This is a graph showing the change in loss factor tanδ of polyethylene with different contents of compound c1 of the present invention. DETAILED DESCRIPTION

[0041] The technical solution of the present invention is described in detail below. The following implementation methods are implemented based on the technical solution of the present invention and provide a detailed implementation process. However, the protection scope of the present invention is not limited to the following implementation methods. In the following implementation methods, structures or experimental methods without specifying specific conditions are generally based on conventional conditions.

[0042] The present invention provides a fluorinated rheological agent having the following structure:

[0043]

[0044] Wherein, n is a positive integer from 1 to 6, i.e., 1, 2, 3, 4, 5, 6. In one embodiment, n is 1, 2, 3 or 4.

[0045] The fluorinated rheological agent of the present invention has a large molecular weight and is not prone to migration loss during processing. In addition, the fluorinated rheological agent of the present invention contains four perfluorohexylsulfonyl fluoride groups in its molecular structure. When added to a polyolefin resin, it can effectively reduce the extrusion torque during the material processing process, eliminate melt fracture and surface wrinkling during the processing process, improve the appearance quality of the product, and increase the melt fluidity of the polyolefin resin material.

[0046] The present invention also provides a method for preparing the above-mentioned fluorinated rheological agent, namely, using an alkyl diamine compound and methyl acrylate as raw materials to synthesize a dendritic macromolecule; in a DMF system, perfluorohexylsulfonyl fluoride is added dropwise to the dendritic macromolecule solution to carry out an amidation reaction, thereby obtaining a fluorinated rheological agent. The method of the present invention is simple to operate, has mild process conditions, and readily available raw materials. A fluorinated rheological agent with improved processing performance can be synthesized only through condensation reaction and amidation reaction. Specifically, the fluorinated rheological agent obtained by the method of the present invention can solve some processing defects that often occur in the melt extrusion process of some high molecular weight, high viscosity polyolefin resins, such as the loss of gloss on the surface of the extrudate in a milder degree, and the melt fracture and surface wrinkling in a more serious degree, thereby affecting the appearance of the product and the extrusion efficiency of the processing equipment.

[0047] In one embodiment, the preparation method of the fluorinated rheological agent of the present invention comprises the following steps:

[0048] Step a, reacting an alkyl diamine compound with methyl acrylate to obtain 0.5G PAMAM dendrimer;

[0049]

[0050] Step b, 0.5 g of PAMAM dendrimer reacts with ethylenediamine to obtain 1.0 g of PAMAM dendrimer;

[0051]

[0052] Step c, reacting 1.0 g of PAMAM dendrimer with perfluoroalkylsulfonyl fluoride to obtain a fluorinated rheological agent;

[0053]

[0054] Here, n is a positive integer from 1 to 6.

[0055] In step a, methyl acrylate and an alkyl diamine compound undergo a condensation reaction to prepare 0.5G PAMAM dendrimers, and the reaction solvent is an alcohol, such as methanol. In one embodiment, the alkyl diamine compound is first dissolved in an alcohol solvent, and then methyl acrylate is added dropwise. The reaction is then carried out at a certain temperature for a certain time. After the reaction is completed, the solvent is removed to obtain 0.5G PAMAM dendrimers. The present invention does not particularly limit the method of removing the solvent, and for example, vacuum distillation is used, and the vacuum distillation temperature is, for example, 50-70°C. In another embodiment, the molar ratio of the alkyl diamine compound to methyl acrylate is 1:4-1:10, for example, 1:8, the reaction temperature is 20-30°C, for example, 25°C, the reaction time is 12-36 hours, for example, 24 hours, and the amount of reaction solvent used is 3-4 times the total mass of the reaction raw materials, that is, the amount of reaction solvent used is 3-4 times the total mass of methyl acrylate and ethylenediamine.

[0056] In one embodiment, the alkyl diamine compound of the present invention has 1-12 carbon atoms, such as ethylenediamine, butanediamine, hexanediamine, octanediamine, dodecanediamine, etc. In another embodiment, the alkyl diamine compound of the present invention is ethylenediamine, butanediamine, hexanediamine, or octanediamine.

[0057] Step b involves condensing 0.5g of PAMAM dendrimer with ethylenediamine to produce 1.0g of PAMAM dendrimer. The reaction solvent is an alcohol, such as methanol. In one embodiment, 0.5g of PAMAM dendrimer is dissolved in an alcohol solvent, and then ethylenediamine is added dropwise. The reaction is carried out at a predetermined temperature for a period of time. After the reaction is complete, the solvent is removed to produce 1.0g of PAMAM dendrimer. The method for removing the solvent is not particularly limited in the present invention, and may be, for example, vacuum distillation at a temperature of, for example, 50-70°C. In another embodiment, the molar ratio of 0.5G PAMAM dendrimer to ethylenediamine is 1:20-1:30, for example, 1:24; the reaction temperature is 20-30°C, for example, 25°C; the reaction time is 12-36 hours, for example, 24 hours; and the amount of the reaction solvent is 3-4 times the total mass of the reaction raw materials, i.e., the amount of the reaction solvent is 3-4 times the total mass of the 0.5G PAMAM dendrimer and ethylenediamine.

[0058] Step c is to modify the terminal amino groups of 1.0G PAMAM dendrimer with perfluoroalkylsulfonyl fluoride to obtain the fluorinated rheological agent of the present invention. In one embodiment, the perfluoroalkylsulfonyl fluoride is a linear perfluoroalkylsulfonyl fluoride, and in another embodiment, the perfluoroalkylsulfonyl fluoride is perfluorohexylsulfonyl fluoride.

[0059] In one embodiment, the molar ratio of 1.0g PAMAM dendrimer to perfluoroalkylsulfonyl fluoride is 1:4-6, for example, 1:5, and the modification reaction temperature is 0-70°C. In another embodiment, 1.0g PAMAM dendrimer is first dissolved in an organic solvent, and then perfluoroalkylsulfonyl fluoride is added dropwise to the 1.0g PAMAM dendrimer solution. The two are mixed and then heated to react. The mixing temperature is 0-5°C, the reaction temperature is 40-70°C, and the reaction time is 2-8 hours. In yet another embodiment, the organic solvent is N,N-dimethylformamide, and the amount of organic solvent is 3-4 times the amount of the starting materials, that is, 3-4 times the amount of organic solvent compared to the total amount of 1.0g PAMAM dendrimer and perfluoroalkylsulfonyl fluoride. In yet another embodiment, the perfluoroalkylsulfonyl fluoride is added dropwise to the 1.0g PAMAM dendrimer solution at a rate of 1-3 drops / min, for example, 2 drops / min.

[0060] The reaction of the 1.0G PAMAM dendrimer with perfluoroalkylsulfonyl fluoride is carried out under an inert atmosphere. The type of the inert gas is not particularly limited in the present invention, and can be, for example, nitrogen, argon, or the like.

[0061] In one embodiment, the reaction process of the 1.0G PAMAM dendrimer of the present invention and perfluoroalkylsulfonyl fluoride is as follows:

[0062] A certain amount of 1.0g of PAMAM dendrimer was added to a three-necked round-bottom flask equipped with a magnetic stir bar, a reflux condenser, and a gas pipe tee. DMF was used as the solvent. After fully dissolving, the system was stirred in a constant-temperature water bath. Air was first evacuated from the system using a circulating water multi-purpose vacuum pump. A certain amount of nitrogen was then introduced into the system using a nitrogen balloon to maintain a nitrogen atmosphere throughout the reaction. This prevented oxygen from oxidizing the system and affecting product synthesis and yield. After nitrogen was introduced, ice cubes or ice packs were placed in the water bath to maintain a temperature of 0-5°C. After stirring for 15 minutes, perfluorohexylsulfonyl fluoride was added to a constant-pressure dropping funnel. The funnel was adjusted to control the addition of perfluorohexylsulfonyl fluoride dropwise into the three-necked flask at a rate of 30s / drop to fully react with the 1.0g PAMAM dendrimer. After a 2-hour ice-water bath reaction, the constant-temperature water bath was raised to 45°C, the condenser was turned on, and the reaction was continued for 6 hours. After the reaction, if the solvent used is N,N-dimethylformamide (DMF), the product is added dropwise to a chloroform solution for precipitation. The resulting precipitate is yellow and filtered through a funnel. After removing the solvent, the resulting precipitate is placed in a vacuum drying oven set to 90°C for 24 hours to remove any remaining solvent and water. This results in a yellow solid powder, which is 1.0 g of PAMAM dendrimer-perfluorohexylsulfonyl fluoride.

[0063] The 1.0G PAMAM dendrimer-perfluorohexylsulfonyl fluoride (wherein n is an integer of 1-6) obtained by the method of the present invention has the following structure:

[0064]

[0065] Because the fluorinated rheological agent of the present invention has four perfluorohexylsulfonyl fluoride groups and a high molecular weight, it is less susceptible to migration losses during the extrusion molding process of polyolefin materials, effectively eliminating periodic melt fracture, lowering the melt temperature during the processing of high-viscosity, high-molecular-weight resins, reducing die pressure and screw torque, increasing output, and improving extrusion efficiency. The fluorinated rheological agent of the present invention is added in an amount of, for example, 0.05%-0.1% by mass of the polyolefin material, and the extrusion temperature is, for example, 190°C. Furthermore, the fluorinated rheological agent of the present invention can be added to polyethylene materials, extruded and pelletized using a twin-screw extruder, and the rheological properties tested.

[0066] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0067] Example 1 Preparation of Compound a1

[0068]

[0069] First, a certain amount of ethylenediamine (9.3g) was added to a 50ml single-necked round-bottom flask with a rotor. The total mass of the single-necked flask and rotor was weighed using an electronic balance and recorded (243.5g). An appropriate amount of methanol (33.2g) was added to the round-bottom flask. The round-bottom flask was placed in an electric constant-temperature water bath and stirred for 15 minutes to allow the raw material ethylenediamine and the solvent methanol to be fully mixed. The water bath temperature was set to 25°C. After stirring for 15 minutes, a certain proportion of methyl acrylate (104.9g) (the molar ratio of ethylenediamine to methyl acrylate was 1:8) was added to a constant-pressure dropping funnel. The methyl acrylate was added dropwise to the round-bottom flask at a rate of 30s / drop to allow the methyl acrylate and ethylenediamine to fully react. The reaction time was 24h. After the reaction was completed, the round-bottom flask was removed and placed in a rotary evaporator for vacuum rotary evaporation for 6h. The initial rotary evaporation temperature was set to 50°C. When no more liquid dripped, a small amount of methanol was added and the rotary evaporation was repeated until no more liquid dripped. During the final hour, the rotary evaporation temperature was increased by 5°C at intervals until it reached 75°C. The resulting pale yellow, transparent liquid was compound a1. The product was removed and weighed on an electronic balance to yield 56.7 g, for a yield of 90.55%.

[0070] Example 2 Preparation of Compound b1

[0071]

[0072] Compound a1 (28.3 g) was added to a 50 ml single-necked round-bottom flask and a rotor was placed. The mass of the single-necked round-bottom flask and rotor was first weighed on an electronic balance and recorded (175.2 g). An appropriate amount of methanol (92.2 g) was added to fully dissolve the solution. The solution was stirred in a thermostatic water bath set to 25°C for 15 minutes. A certain ratio of ethylenediamine (a molar ratio of compound a1 to ethylenediamine of 1:24) was weighed on an electronic balance (100.8 g) and poured into a constant pressure dropping funnel. The piston of the funnel was adjusted to control the droplet addition rate to control the droplet addition to the round-bottom flask at a rate of 30 seconds per drop. The reaction was fully reacted with compound a1 for 24 hours. After the reaction was completed, the solution was evaporated under reduced pressure for 6 hours. The initial rotary evaporation temperature was set to 50°C. When no more liquid dripped, a small amount of methanol was added and the rotary evaporation was repeated. During the final hour, the rotary evaporation temperature was increased by 5°C at intervals until it reached 75°C. The resulting pale yellow, viscous liquid was Compound b1. The mass was measured on an electronic balance to be 36.1 g, for a yield of 99.88%.

[0073] Example 3 Preparation of Compound c1

[0074]

[0075] Compound b1 (0.9 g) was added to a three-necked round-bottom flask equipped with a magnetic stirrer, a reflux condenser, and a three-way gas pipe. The total mass of the three-necked round-bottom flask and rotor was weighed using an electronic balance and recorded (162.7 g). An appropriate amount of N,N-dimethylformamide (DMF) (15.5 g) was added as a solvent. The system was stirred with a glass rod until compound b1 was fully dissolved in DMF. The system was then placed in a constant temperature water bath and stirred for 15 minutes. The entire system was maintained under nitrogen during the reaction. After nitrogen was introduced, the system was kept in an ice-water bath at 0-5°C. After stirring for 15 minutes, 3.5 g of perfluorohexylsulfonyl fluoride was weighed and added to a constant pressure dropping funnel. The funnel was adjusted to control the rate of 30 drops per drop to fully react with compound b1. The reaction time was 2 hours. After a 2-hour ice-water bath reaction, the constant-temperature water bath was raised to 45°C, the condenser water was turned on, and the reaction was continued for another 6 hours. After the reaction, the product was added dropwise to a chloroform solution for precipitation. The resulting precipitate was yellow. The precipitated solution was filtered through a funnel to remove the solvent. The resulting precipitate was then vacuum-dried in a vacuum drying oven set to 90°C for 24 hours. A yellow solid powder was obtained, which was weighed to yield 2.3 g of compound C1, for a yield of 64.52%.

[0076] Example 4 Solvent Optimization for Synthesis of Compound C1

[0077] This example compares the solvent types used in the synthesis of Compound C1. Three experiments were conducted using N,N-dimethylformamide as the solvent and the same reaction conditions as in Example 3. Three experiments were conducted using chloroform as the solvent and the same reaction conditions as in Example 3. After the reaction, the product solvent was mostly evaporated, filtered, and dried under vacuum at 90°C for 24 hours. The yields of Product C1 obtained using different solvents are shown in Table 1 below.

[0078] Table 1 Solvent-yield comparison

[0079]

[0080] Example 5 Optimization of the reactant molar ratio in the synthesis of compound c1

[0081] This example investigates the optimal molar ratio of reactant b1 to perfluorohexanesulfonyl fluoride in the synthesis of compound c1. Experiments were conducted using five different molar ratios of compound b1 to perfluorohexanesulfonyl fluoride. The variables were controlled, and the remaining experimental conditions were the same as in Example 3. The reaction results are shown in Table 2.

[0082] Table 2 Comparison of reactant molar ratio and yield

[0083] reactant molar ratio 1∶4 1∶4.5 1∶5 1∶5.5 1∶6 Product yield % 39.6 41.6 63..3 56.7 50.6

[0084] If the ratio of PAMAM to perfluorinated compound as the raw material is too low, the reaction will be incomplete, while if the ratio is too high, the loss will increase during the subsequent processing, thereby resulting in a lower yield.

[0085] Infrared spectral characteristics of compounds b1 and c1 in Example 6

[0086] Compounds b1 and c1 were analyzed using a Tensor 27 Fourier transform infrared spectrometer using the smear method. Compound b1 was analyzed by first pressing a KBr blank smear, then evenly smearing the compound b1 dendrimer onto the blank KBr pressed tablet, and then analyzing the smear using the Fourier transform infrared spectrometer. Compound c1, prepared experimentally, was analyzed by first grinding and mixing KBr powder and rheological agent powder, then pressing the powder into a tablet, and then analyzing the smear using the Fourier transform infrared spectrometer.

[0087] Depend on Figure 1 As shown, at a wave number of 1655 cm -1 The strong absorption peak at 2360 cm-1 is the characteristic absorption peak of carbonyl stretching vibration; -1 and 2166cm -1 The absorption peaks at the wave number of 1609cm-1 are the asymmetric and symmetric stretching vibrations of the two methylene groups -CH2-. There is a certain offset in the absorption peaks of these two groups. -1 It is the characteristic absorption peak of δNH+υCN; at the wave number of 3437cm -1 3334cm -1 The strong absorption characteristic stretching vibration peak of -NH2 is at 1452cm -1 The bending and stretching vibration of methylene -CH2- is at the wave number of 1183cm -1 and 1109cm -1 The above are the characteristic absorption peaks of primary amine and tertiary amine respectively, which are the infrared characteristic absorption peaks of compound b1. Figure 1 From the infrared spectrum, it can be seen that the tested compound contains characteristic groups such as -CONH-, -NH2, and -CH2-. The compound synthesized in Example 2 has the structure of the above-mentioned compound b1.

[0088] Depend on Figure 2 As shown, at a wave number of 1661 cm -1 The strong absorption peak at 2348 cm is the characteristic absorption peak of carbonyl stretching vibration; -1 and 2169cm -1 The absorption peaks at the wave number of 3439cm- -1 The wave number is 3334cm-1 The absorption peak at wave number 1184cm is the strong absorption characteristic stretching vibration peak of -NH; -1 and 1145cm -1 The peaks of symmetric and antisymmetric stretching vibrations of CF are at 1145 cm -1 The peak of S=O=S stretching vibration is at the wave number of 1367cm -1 The characteristic absorption peak of -SO2-NH- appears at Figure 2 Analysis of the infrared spectrum shows that the synthesized compound c1 contains characteristic groups such as -NH, -CH2-, -CONH-, -SO2-NH-, and CF, and has the above-mentioned expected structure.

[0089] Example 7 H-NMR analysis of compound c1

[0090] Compound C1, prepared experimentally, was tested for its H NMR performance using a JNM-ECZ500R NMR spectrometer. The test method involved dissolving 20 mg of compound C1 in 1.0 mL of deuterated chloroform in a 5 mm NMR tube. The solution was filtered and then added to the tube using a dropper, ensuring the sample solution was no more than 3 cm high. After the solution was added, the tube was capped to prevent sample evaporation and labeled on the side to prevent sample mix-up.

[0091] Depend on Figure 3 As shown, the peak of δ at around 1.95-2.05 (3) is the characteristic absorption peak of the proton on the methylene group connected to the carbonyl group; the peak of δ at around 2.16-2.26 (1) is the characteristic absorption peak corresponding to the proton on the methylene group connected to the tertiary amine in the initial core; the peak of δ at around 3.38-3.47 (2) is the absorption peak corresponding to the proton on the methylene group on the side chain connected to the tertiary amine; the peak of δ at around 3.0-3.12 (5, 6) is the absorption peak corresponding to the proton on the methylene group connected to the secondary amine connected to the carbonyl group; the peak of δ at 7.45 (4) is the absorption peak corresponding to the proton on the secondary amine N connected to the carbonyl group; the peak of δ at 7.03 (7) is the characteristic absorption peak of the proton on the secondary amine N connected to the sulfonyl group; the peak of δ at 7.18-7.26 (8) is the characteristic absorption peak of the solvent. Therefore, according to Figure 3 It can be confirmed that the compound synthesized in Example 3 has the above-mentioned c1 structure.

[0092] Example 8 Melting Point Determination of Compound C1

[0093] A WRS-1B digital melting point instrument was used to test the melting point of compound C1 synthesized in the experiment. Compound C1 was dried and ground to an extremely fine and uniform state. The sample was placed in a capillary tube and allowed to fall to the bottom of the capillary tube by gravity, minimizing the gap between the sample and the sample on the capillary wall. The instrument's preset initial temperature was set to 35°C, and the heating rate was set to 1.5°C / min. After the instrument reached the preset temperature and stabilized, the capillary tube with the sample was inserted into the instrument's test port and the measurement began. The measurement was repeated three times in parallel. The measurement results are shown in Table 3.

[0094] Table 3 Melting point test results

[0095] frequency Initial melting point / ℃ Final melting point / ℃ Melting point difference / ℃ 1 104.3 107.3 3.0 2 101.9 103.8 1.9 3 104.3 106.9 2.6 average value 103.5 106.0 2.5

[0096] As shown in Table 3, the melting point range of the synthesized compound C1 was between 100°C and 110°C. The smallest temperature difference between the initial and final melting points of the three tests was 1.9°C in the second run, while the largest temperature difference was 3.0°C in the first run. Both values ​​were less than 5°C. The average initial melting point of the three tests was 103.5°C, and the average final melting point was 106.0°C, with an average melting point difference of 2.5°C, less than 5°C. This indicates that the synthesized compound C1 is relatively pure.

[0097] Example 9 Extrusion performance test of compound c1

[0098] The extrusion performance of compound C1 prepared in the experiment was measured using a Thermo Haake Polylab Rheomex multifunctional testing machine. The equipment speed was set at 100 r / min. -1 The torque value was recorded every 5 minutes. High-density polyethylene with compound c1 content of 0%, 0.1% and 0.05% (mass fraction, the same below) was mixed and shaken, and the powder was poured into the inlet of the multi-functional testing machine. The twin-screw compounding and granulating machine was used for compounding and granulating at 170-190°C. The pellets were prepared for the subsequent determination of rheological properties. The extrusion torque of the product was analyzed to obtain the relationship between extrusion time and extrusion torque.

[0099] Depend on Figure 4As shown, regardless of whether Compound C1 was added, the extrusion torque of polyethylene decreased with increasing extrusion time, reaching a plateau after 50 minutes. Before reaching plateau, the rate of decrease in extrusion torque varied with the addition of different Compound C1 contents. The minimum torque was reached at 35 minutes for polyethylene with a 0.1% Compound C1 content, 45 minutes for polyethylene with a 0.05% Compound C1 content, and 50 minutes for polyethylene with a 0% Compound C1 content. For the same extrusion time, high-density polyethylene with a 0.1% Compound C1 content had the lowest extrusion torque, while polyethylene without Compound C1 had the highest extrusion torque. For the same extrusion torque, polyethylene with a 0.1% Compound C1 content required the shortest extrusion time, while polyethylene without Compound C1 required the longest extrusion time.

[0100] Example 10 Determination of rheological properties of compound c1

[0101] (1) Melt mass flow rate

[0102] The melt flow rate of polyethylene with compound c1 contents of 0.1%, 0.05% and 0% (mass fraction) was measured using a melt flow rate meter model MI-4 manufactured by Shanghai Yarong Biochemical Instrument Factory. The measurement results are shown in Table 4 below.

[0103] Table 4 Melt mass flow rate of three polyethylene samples

[0104]

[0105] As shown in Table 4, the melt flow rates of the three polyethylenes are ranked from highest to lowest in the order of WJ-0.1% > WJ-0.05% > WJ-0%. This indicates that the polyethylene containing 0.1% by mass of compound C1 exhibits superior melt flowability, making it more suitable for applications such as injection molding. The melt flow rate can also qualitatively reflect the molar masses of the three samples. Generally speaking, when comparing similar grades, samples with higher melt flow rates correspond to lower molar masses.

[0106] (2) Angular frequency, modulus, and shear viscosity

[0107] The relationship between angular frequency and storage modulus, loss modulus and shear viscosity of polyethylene with different contents of compound C1 was measured at a temperature of 190°C using a MCR302 rotational rheometer produced by Anton Paar GmbH, Austria. The angular frequency-modulus-shear viscosity curve of polyethylene was obtained as shown in the figure below. Figure 5 、 Figure 6 、 Figure 7、 Figure 8 、 Figure 9 shown.

[0108] Depend on Figure 5 、 Figure 6 、 Figure 7 It can be seen that as the angular frequency increases, the storage modulus G′ and loss modulus G″ of polyethylene both increase accordingly. The polyethylene of the three groups with different contents of compound c1 has G′>G″ at high frequencies, that is, the sample does not flow within a very short stress time and exhibits a solid state; at low frequencies, the polyethylene has G′<G″, that is, the sample flows within a longer stress time and exhibits a fluid state.

[0109] Depend on Figure 8 It can be seen that at the same temperature, the shear viscosity of the three groups of polyethylene decreases with increasing angular frequency, with the overall trend being consistent but with slight differences. This is because when the angular frequency increases to a certain value, the entanglements between the molecular chains are disentangled. This reduction in fluid viscosity is attributed to the "shear thinning effect," which is a pseudoplastic rheological behavior. At the initial shear rate, the addition of a small amount of fluorinated rheological agent forms physical entanglement points in the mixed system. The presence of these entanglement points slightly increases the apparent viscosity of the polyethylene with WJ-0.1% and WJ-0.05%, but the difference is not significant. As the shear rate increases, the molecular entanglement points of the polyethylene with the fluorinated rheological agent disentangle, the apparent viscosity of the system decreases more significantly, and the fluidity of the polyethylene is improved.

[0110] The loss factor tan δ is the ratio of the loss modulus G″ to the storage modulus G′, reflecting the relationship between the viscosity and elasticity of the material. The lower the loss factor, the better the material's ability to recover after deformation, and vice versa. For material processing and molding, the loss factor describes the ability of the composite material melt to recover after deformation under shear stress. Figure 9 As can be seen, the loss factor of the polyethylene systems with varying fluorinated rheological agent contents all show a decreasing trend with increasing angular frequency. However, the polyethylene systems with WJ-0.05% and WJ-0.1% exhibit internal friction peaks at certain frequencies. This is primarily due to the significant change in the response of the relative motion of the intermolecular segments to external forces as the scanning frequency increases. The peak intensity decreases with increasing fluorinated rheological agent content, indicating that fluorinated rheological agents can enhance the resilience of polyethylene.

[0111] Example 11 Preparation of Compound d1

[0112]

[0113] n-Butanediamine (12g) was added to a 250ml single-necked round-bottom flask containing a rotor. 35g of methanol was added and stirred in an electric constant-temperature water bath at 25°C for 15 minutes to fully dissolve the mixture. After stirring for 15 minutes, methyl acrylate (93.7g) in a certain ratio (a molar ratio of n-butanediamine to methyl acrylate of 1:8) was added dropwise to a constant-pressure dropping funnel at a rate of 30s / drop. After the addition was complete, the methyl acrylate and n-butanediamine were allowed to react in a 30°C water bath for 24 hours. After the reaction, the round-bottom flask was removed and subjected to rotary evaporation, initially at 50°C. When no more liquid dripped, a small amount of methanol was added and the evaporation was repeated until no more liquid dripped. During the final hour, the evaporation temperature was increased by 5°C at intervals until it reached 75°C. The resulting pale yellow, transparent liquid was compound d1. The mass of the compound was 57.0g using an electronic balance, with a yield of 96.94%.

[0114] Example 12 Preparation of Compound e1

[0115]

[0116] Compound d1 (20 g) was added to a 250 ml single-necked round-bottom flask. An appropriate amount of methanol (90 g) was added to fully dissolve the mixture. The mixture was then placed in a constant-temperature water bath at 25°C and stirred for 15 minutes. A constant-pressure dropping funnel was added with ethylenediamine (66.7 g) in a certain ratio (a molar ratio of compound e1 to ethylenediamine of 1:24) and added dropwise to the round-bottom flask at a rate of 30 seconds per drop. The temperature was raised to 30°C and allowed to react for 24 hours. After the reaction, the solvent was removed by rotary evaporation under reduced pressure. The initial rotary evaporation temperature was set at 50°C. When no liquid dripped, small amounts of methanol were added repeatedly. The rotary evaporation temperature was increased by 5°C over the final hour until it reached 75°C. Compound e1 was obtained as a pale yellow, viscous liquid. Its mass was 23.5 g, and the yield was 93.33%.

[0117] Example 13 Preparation of Compound f1

[0118]

[0119] 2.0g of compound e1 was placed in a dry 100ml three-necked flask, dissolved in 16g of DMF, and 0.9g of triethylamine, an acid binder, was added. The mixture was stirred in a 15°C constant-temperature magnetic stirring water bath for 15 minutes. The reflux water was turned on, and 7.39g of perfluorohexanesulfonyl fluoride was added to a constant-pressure dropping funnel. Nitrogen was introduced and the mixture was added dropwise in an ice-water bath at 0-5°C at a rate of one drop every 30 seconds. The reaction was continued for 2 hours after the addition was complete. After 2 hours of ice-water reaction, the reaction was continued at 45°C for 6 hours. After the reaction was completed, the product was slowly added dropwise to a large amount of chloroform to obtain a light yellow precipitate. The solvent was removed by suction and the mixture was dried under vacuum for 24 hours to obtain a light yellow solid powder, compound fl, weighing 4.64g and a yield of 60.9%.

[0120] Example 14 Preparation of Compound g1

[0121]

[0122] Weigh n-hexanediamine (15 g) and add it to a 250 ml single-necked round-bottom flask. Then measure methanol (35 g) to dissolve it. After placing a rotor, place the flask in a water bath at 35 ° C and stir for 15 minutes to fully mix it. Add a certain proportion of methyl acrylate (89 g) (the molar ratio of n-octanediamine to methyl acrylate is 1:8) to a constant pressure dropping funnel and add it dropwise at a rate of 30 seconds per drop. Allow methyl acrylate and n-octanediamine to fully react for 24 hours. After the reaction is completed, the solvent is removed by rotary evaporation. The rotary evaporation temperature is set to 50 ° C. When no liquid drips, methanol is added again and rotary evaporation is performed multiple times. The temperature of the last rotary evaporation is increased by 5 ° C every time until it reaches 75 ° C. Finally, 52.2 g of a light yellow transparent liquid, compound g1, is obtained, with a calculated yield of 87.76%.

[0123] Example 15 Preparation of Compound h1

[0124]

[0125] Compound g1 (20 g) was weighed and added to a 250 ml round-bottom flask. An appropriate amount of methanol (90 g) was added to dissolve the mixture. A rotor was placed in the flask and stirred in a constant temperature water bath for 15 minutes. A certain proportion of ethylenediamine (compound f1:ethylenediamine molar ratio of 1:20) was weighed (52.2 g) and poured into a constant pressure dropping funnel. The mixture was added dropwise to the round-bottom flask at a rate of 30 seconds per drop to allow for full reaction. After the addition was complete, the temperature was set to 35°C and the reaction was allowed to proceed for 24 hours. After the reaction was completed, the methanol was removed by rotary evaporation at 65°C. When no liquid dripped, methanol was added again and the rotary evaporation was continued several times, with the final rotary evaporation temperature raised to 75°C and continued for half an hour. The resulting pale yellow viscous liquid was compound h1. 21.6 g of the mixture was removed and weighed, with a yield of 86.88%.

[0126] Example 16 Preparation of Compound I1

[0127]

[0128] Take compound h1 (2.0g) and add it to a three-necked round-bottom flask. Add N,N-dimethylformamide (20g) to dissolve it. Put a rotor and stir the flask in a constant temperature water bath for 15 minutes. Weigh 7.0g of perfluorohexanesulfonyl fluoride and add it to a constant pressure dropping funnel. After passing nitrogen, add perfluorohexanesulfonyl fluoride dropwise at a rate of 30s / drop in an ice-water bath at 0-5°C. After the addition is complete, continue the reaction for 2h. After 2h, open the condensation water and heat it to 40°C and continue the reaction for 4h. After the reaction is completed, the product is added dropwise to chloroform to obtain a light yellow precipitate. The solvent is removed by suction, and the precipitate is washed and dried in a vacuum oven for 24 hours. A light yellow solid powder is obtained and weighed to obtain 4.32g of compound I1 with a yield of 58.85%.

[0129] Example 17 Melting Point Determination of Compound f1

[0130] A digital melting point instrument was used to measure the melting point of compound F1. After drying, compound F1 was ground into a very fine and uniform state. The sample was placed in a capillary tube and allowed to fall by gravity to the bottom of the capillary tube, minimizing any gaps between the sample and the capillary wall. The instrument was set to an initial temperature of 80°C and a heating rate of 1.5°C / min. After the instrument reached the preset temperature and stabilized, the capillary tube containing the sample was inserted into the instrument's test port and the measurement was initiated. Three replicate measurements were performed. The results are shown in Table 5.

[0131] Table 5 Melting point test results

[0132] frequency Initial melting point / ℃ Final melting point / ℃ Melting point difference / ℃ 1 146.8 148.7 1.9 2 145.9 148.0 2.1 3 146.0 147.8 1.8 average value 146.2 148.2 2.0

[0133] As shown in Table 5, the melting point of the synthesized compound f1 ranged from 145°C to 150°C. The smallest difference between the initial and final melting points of the three tests was 1.8°C in the third run, while the largest difference was 2.10°C in the second run, both less than 5°C. The average initial melting point of the three tests was 146.2°C, and the average final melting point was 148.2°C, with an average melting point difference of 2.0°C, less than 5°C. This indicates that the synthesized compound f1 is relatively pure.

[0134] Example 18 Melting Point Determination of Compound 11

[0135] A digital melting point instrument was used to test the melting point of compound I1. After drying, compound I1 was ground to an extremely fine and uniform state. The sample was then placed into the bottom of a capillary tube by gravity, compacting it until there were virtually no gaps. The instrument's initial temperature was set to 100°C, with a heating rate of 1.5°C / min. After the instrument reached the preset temperature and stabilized, the capillary tube was inserted into the instrument's test port and the measurement began. Three replicates were performed. The results are shown in Table 6.

[0136] Table 6 Melting point test results

[0137] frequency Initial melting point / ℃ Final melting point / ℃ Melting point difference / ℃ 1 161.5 166.1 4.6 2 160.9 166.4 5.5 3 161.4 166.0 4.6 average value 161.3 166.2 4.9

[0138] As shown in Table 6, the melting point of compound f1 ranges from 160°C to 170°C. The largest difference between the initial melting point and the melting range was observed in the second run, at 5.5°C. The average initial melting point of the three runs was 161.3°C, and the average final melting point was 166.2°C. The average melting point difference was 4.9°C, less than 5°C, indicating that compound I1 synthesized in this experiment was relatively pure.

[0139] Thus, the present invention provides a fluorine-containing rheological agent, which is synthesized by condensation reaction and amidation reaction using diamine, methyl acrylate and perfluorohexylsulfonyl fluoride as raw materials. The molecular weight of the rheological agent is relatively large, and migration loss is not easy to occur during processing and use. At the same time, the molecular structure of the rheological agent contains four perfluorohexylsulfonyl fluoride groups, so the surface energy of the processing aid is low, and an incompatible dispersed phase existing in the matrix resin is formed in the form of extremely small particles. During the material processing process, the low-surface-energy particles migrate to the surface of the melt and contact the metal surfaces of the barrel, screw and die head, gradually forming a coating between the polymer melt and the metal surface of the equipment that allows the processed polymer to slide smoothly. It is this migration effect and coating that reduce the adhesion between the melt and the metal, and the shear stress is also significantly reduced. At the same time, the raw materials of the synthesis process of the present invention are easily available, the operation is simple, and it is easy to implement. The synthetic product is applied to polyethylene, which can effectively improve the processing performance of the material and has important guiding significance for the development and use of polyolefin processing aids.

[0140] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims of the present invention.

Claims

1. A fluorinated rheological agent, characterized in that: It has the following structure: Here, n is a positive integer from 1 to 6.

2. A method for preparing a fluorinated rheological agent, characterized in that: The steps include: 1.0 g of PAMAM dendrimer was reacted with perfluoroalkylsulfonyl fluoride to obtain a fluorinated rheological agent; Here, n is a positive integer from 1 to 6.

3. The method for preparing a fluorinated rheological agent according to claim 2, wherein: The molar ratio of 1.0GPAMAM dendrimer to perfluoroalkylsulfonyl fluoride is 1:1-1:10, and the reaction temperature is 0-70°C.

4. The method for preparing a fluorinated rheological agent according to claim 2, wherein: The mixing temperature of 1.0GPAMAM dendrimer and perfluoroalkylsulfonyl fluoride is 0-5°C, and the reaction temperature is 0-70°C.

5. The method for preparing a fluorinated rheological agent according to claim 2, wherein: The preparation method of the 1.0G PAMAM dendrimer comprises: Step a, reacting an alkyl diamine compound with methyl acrylate to obtain 0.5G PAMAM dendrimer; Step b, 0.5 g of PAMAM dendrimer reacts with ethylenediamine to obtain 1.0 g of PAMAM dendrimer; 6. The method for preparing a fluorinated rheological agent according to claim 5, characterized in that: In step a, the molar ratio of the alkyl diamine compound to methyl acrylate is 1:4-1:10, and the reaction temperature is 20-30°C; in step b, the molar ratio of 0.5G PAMAM dendrimer to ethylenediamine is 1:20-1:30, and the reaction temperature is 20-30°C.

7. The method for preparing a fluorinated rheological agent according to claim 2, wherein: The solvent for the reaction of 1.0G PAMAM dendrimer and perfluoroalkylsulfonyl fluoride is N,N-dimethylformamide, and the solvent for the reaction is 3-4 times the total mass of the 1.0G PAMAM dendrimer and perfluoroalkylsulfonyl fluoride.

8. The method for preparing a fluorinated rheological agent according to claim 2, wherein: The perfluoroalkylsulfonyl fluoride is dropped into the solution formed by 1.0G PAMAM dendrimer at a rate of 1-3 drops / min and mixed; the reaction is carried out under an inert atmosphere.

9. The method for preparing a fluorinated rheological agent according to claim 5, wherein: The solvents for the reaction of the alkyldiamine compound with methyl acrylate and the reaction of 0.5G PAMAM dendrimer with ethylenediamine were alcohols.

10. Use of the fluorinated rheological agent according to claim 1 in polyolefin materials.

Images