Fluorocarbon resin with block copolymer and preparation method and application thereof

Abstract

The invention relates to fluorocarbon resin with a block copolymer as well as a preparation method and application thereof, and relates to the technical field of new materials. The fluorocarbon resin is prepared by adopting a cationic polymerization method or an atom transfer radical polymerization method, and reaction raw materials comprise fluorine-containing monomers; the fluorine-containing monomer comprises at least one of pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate. The fluorocarbon resin has the reactive block copolymer, and fills up the blank that in the prior art, no fluorocarbon resin with the block copolymer is synthesized by taking a fluorine-containing monomer as a raw material temporarily.

Description

Technical Field

[0001] The present invention relates to the technical field of new materials, and in particular to a fluorocarbon resin with a block copolymer, a preparation method and an application thereof. Background Art

[0002] Fluorocarbon resin refers to a synthetic polymer compound containing fluorine atoms on the carbon chain of the main chain or side chain. It has been widely used in the fields of construction, chemical industry, and electronic and electrical industry, such as coatings, plastic products, and insulating materials. The notable feature of fluorocarbon resin is that it has a strong CF bond as the skeleton, and the fluorine atoms are closely arranged around the carbon main chain. Because the electronegativity of fluorine atoms is large and the carbon-fluorine bond energy is strong, the CF bond can form a highly three-dimensional shielding effect on the CC bond. This special structure also gives fluorocarbon resin many excellent properties, such as excellent performance in heat resistance, weather resistance, electrical properties, and low-temperature flexibility. For example, fluorocarbon resin coatings are not prone to powdering and fading after long-term outdoor use, and their service life can usually reach more than 20 years. Coatings used for building exterior walls can provide long-term protection and aesthetic effects, or protective coatings used for aircraft exteriors to withstand harsh climatic conditions.

[0003] Regarding the study of fluorocarbon resins, some researchers synthesized hydrogenated rosin alcohol acrylate with hydrogenated rosin alcohol and acryloyl chloride, and then used the semi-continuous solvent addition method to copolymerize the product with acrylic acid and its derivatives to synthesize a series of bio-based modified fluorocarbon resins. The results show that with the increase of the mass fraction of hydrogenated rosin alcohol acrylate, the kinematic viscosity of the bio-based modified fluorocarbon resin decreases, and compared with the control group, the spatial effect of hydrogenated rosin alcohol acrylate is more obvious, which can reduce the intermolecular interaction force, thereby achieving a better viscosity reduction effect. In terms of film performance, the film hardness of the bio-based modified fluorocarbon resin is 3H, the adhesion is 7.57MPa, and the film drying time is 2.0h, which has good corrosion resistance. Some researchers also used tetrafluoroethylene and non-fluorine monomers as monomers to develop electron beam cured modified FEVE fluorocarbon resin. After testing the physical and chemical properties of the coating sample, it can be seen that the obtained fluorocarbon resin also exhibits the characteristics of smooth appearance, high pencil hardness, low gloss loss rate and strong boiling water adhesion at 3h and 6h. Other researchers have copolymerized nano-silica-modified fluorocarbon resins based on nano-silica and fluorinated acrylate solutions, which significantly improved the coating's water resistance, aging resistance, and pencil hardness. Moreover, this fluorocarbon resin does not require heating or oxygen isolation, and can be cured by visible light at room temperature, which greatly broadens its practical application scenarios. Other researchers have synthesized fluorocarbon resins using tetrafluoroethylene and isobutylene as reaction monomers. This fluorocarbon resin is a thermosetting tetrafluorocarbon powder coating resin with a glass transition temperature above 60°C.

[0004] However, at present, there is no fluorocarbon resin for synthesizing block copolymers based on fluorinated monomers such as fluorostyrene, pentafluorostyrene or octafluoropentyl acrylate. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a fluorocarbon resin having a block copolymer. The fluorocarbon resin is prepared from a fluorine-containing monomer such as pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate, and has a reactive block copolymer.

[0006] In order to achieve the above object, the present invention provides a fluorocarbon resin having a block copolymer, wherein the fluorocarbon resin is prepared by cationic polymerization or atom transfer radical polymerization, and the reaction raw materials include a fluorine-containing monomer;

[0007] The fluorine-containing monomer includes at least one of pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate.

[0008] In one embodiment, the structural formula of the fluorocarbon resin is shown in any one of Formulas 1-4:

[0009]

[0010] In one embodiment, the weight average molecular weight M of the fluorocarbon resin is w It is 13000~18000, and the glass transition temperature is ≥80℃.

[0011] The present invention also provides a method for preparing the fluorocarbon resin, wherein the reaction raw materials are prepared by cationic polymerization or atom transfer radical polymerization to obtain the fluorocarbon resin, and the reaction raw materials include fluorine-containing monomers;

[0012] The fluorine-containing monomer includes at least one of pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate.

[0013] In one embodiment, the cationic polymerization method comprises the following steps: dissolving a fluorine-containing monomer to obtain a fluorine-containing monomer solution, dissolving a polymerizable monomer to obtain a polymerizable monomer solution, adding a catalyst to the fluorine-containing monomer solution, reacting at a temperature of (-1°C)-0°C for 0.8-1.2h, adding the polymerizable monomer solution, reacting at a temperature of (-1°C)-0°C for 1.5-2h, and obtaining a fluorocarbon resin;

[0014] The fluorine-containing monomer includes fluorostyrene, the polymerizable monomer includes divinylbenzene, and the catalyst includes tin tetrachloride; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, and the catalyst is (8-12): (18-22): (0.8-1.2).

[0015] In the cationic polymerization method, the reaction monomer needs to ensure moderate activity and reactivity to ensure effective block formation, and the active monomer is the growth active center of cationic polymerization. Since divinylbenzene is selected as the polymerization monomer, its activity is much higher than that of the fluorine-containing monomer. Therefore, the above preparation method first allows the fluorine-containing monomer to be preliminarily polymerized in a polar solvent, and then the polymerization monomer is added to it. Secondly, the greater the polarity and solvation capacity of the solvent, the more it can promote the looseness of ion pairs and the formation of free ions, so that the polymerization rate and molecular weight are increased, but the segment of the polymer will be deteriorated, so low-level halogenated alkane is selected as the solvent, and methylene chloride is specifically selected in the present invention. In addition, the cationic polymerization reaction is selected at low temperature because the polymerization rate will increase as the temperature decreases, and the polymerization degree and stereoregularity of the polymer are improved. Finally, a suitable catalyst is selected to provide a suitable catalytic activity to optimize the cationic polymerization rate and molecular weight.

[0016] In one embodiment, in the cationic polymerization method, after reacting at a temperature of (-1°C)-0°C for 1.5-2h, there is also an extraction step, and the extraction comprises: precipitating the reaction solution obtained after reacting at a temperature of (-1°C)-0°C for 1.5-2h in methanol to obtain a fluorocarbon resin.

[0017] In one embodiment, the atom transfer radical polymerization method comprises the following steps: mixing a fluorine-containing monomer, a free radical initiator, a catalyst, and a solvent, reacting at a temperature of 100° C.-110° C. for 10-250 minutes, adding a polymerization monomer, heating to 100° C.-140° C., reacting for 80-140 minutes, and obtaining a fluorocarbon resin;

[0018] The free radical initiator includes benzyl bromide, and the catalyst includes copper bromide and bipyridine.

[0019] In the atom transfer radical polymerization method, alkyl halides are selected as free radical initiators, and the chain is extended by transition metal catalysts or degenerate transfer. The free radicals are reversibly passivated and become dormant species, which can effectively inhibit premature chain termination reactions and achieve the purpose of controlling the molecular weight of the polymer. Secondly, in the synthesis process of block copolymers, it is necessary to control the order and proportion of monomer addition to ensure that the formation and molecular weight of each block meet the target results. At the same time, a relatively weakly polar solvent is selected to avoid affecting the activity of the catalyst and the polymerization rate constant, etc., to ensure the steady progress of the polymerization reaction and the stability of the catalyst, while also achieving the expected research results in terms of polymerization rate and molecular weight distribution.

[0020] Moreover, due to the large difference in the activity of the two comonomers (fluorinated monomer and divinylbenzene) selected by the present invention, if the two are mixed together and the polymerization reaction is carried out simultaneously, the activity of divinylbenzene is much higher than that of fluorinated monomer, resulting in only the homopolymer of divinylbenzene being obtained in the end. However, the inventors try to increase the probability of fluorinated monomer participating in the polymerization by increasing the reaction temperature or extending the reaction time, and such operation will lead to the crosslinking of divinylbenzene. Therefore, the inventors propose that both cationic polymerization and atom transfer radical polymerization adopt a two-stage copolymerization reaction, that is, firstly completing the reaction in the first stage to obtain a polymer of fluorinated monomer, and then adding divinylbenzene to copolymerize with it, so as to obtain the target product that meets the requirements of the present invention.

[0021] In one embodiment, the atom transfer radical polymerization method includes the following steps: mixing a fluorine-containing monomer, a free radical initiator, a catalyst, and a solvent, reacting at a temperature of 100°C-110°C for 10-80 minutes, adding a polymerization monomer, heating to 100°C-140°C, and reacting for 85-140 minutes.

[0022] In one embodiment, the atom transfer radical polymerization method further includes an extraction step after heating to 100°C-140°C and reacting for 85-140 minutes. The extraction includes: precipitating the reaction solution obtained after reacting at a temperature of 120°C-140°C for 110-140 minutes in methanol, decanting, filtering, and drying to obtain a fluorocarbon resin; or shaking and dissolving the reaction solution with dichloromethane, filtering, taking the filtrate, extracting the dichloromethane layer, drying, and concentrating to obtain a fluorocarbon resin.

[0023] In one embodiment, the fluorine-containing monomer includes fluorostyrene, and the polymerizable monomer includes divinylbenzene; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, the free radical initiator, copper bromide, and bipyridine is (78-84): (68-72): (0.8-1.2): (0.8-1.2): (1.8-2.2).

[0024] In one embodiment, the fluorine-containing monomer includes pentafluorostyrene, and the polymerizable monomer includes divinylbenzene; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, the free radical initiator, copper bromide, and bipyridine is (68-72): (68-72): (0.8-1.2): (0.8-1.2): (1.8-2.2).

[0025] In one embodiment, the fluorine-containing monomer includes octafluoropentyl acrylate, and the polymerizable monomer includes divinylbenzene; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, the free radical initiator, copper bromide, and bipyridine is (13-17): (58-62): (0.8-1.2): (0.8-1.2): (2.8-3.2).

[0026] The present invention also provides application of the fluorocarbon resin or the fluorocarbon resin obtained by the preparation method in building materials, chemical materials and electronic materials.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention discloses a fluorocarbon resin having a block copolymer, a preparation method and an application thereof. The fluorocarbon resin is prepared from fluorine-containing monomers such as pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate, and has a reactive block copolymer, thus filling the gap in the prior art that there is no fluorocarbon resin having a block copolymer synthesized from fluorine-containing monomers as raw materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is the chemical reaction formula for synthesizing fluorocarbon resins from different fluorine-containing monomers in different embodiments, wherein: Figure 1 (a) is the chemical reaction formula for forming a copolymer by cationic polymerization of fluorostyrene and divinylbenzene in Example 1, Figure 1 (b) is the chemical reaction formula for forming a copolymer by atom transfer radical polymerization of fluorostyrene and divinylbenzene in Example 4, Figure 1 (c) is the chemical reaction formula for forming a copolymer of pentafluorostyrene and divinylbenzene by atom transfer radical polymerization in Example 5, Figure 1 (d) is the chemical reaction formula for forming a copolymer by atom transfer radical polymerization of octafluoropentyl acrylate and divinylbenzene in Example 6;

[0030] Figure 2 The fluorocarbon resin prepared in different embodiments 1 H NMR spectrum, where Figure 2 (a) The fluorocarbon resin prepared in Example 1 1 H NMR spectrum, Figure 2 (b) The fluorocarbon resin prepared in Example 4 1 HNMR spectra;

[0031] Figure 3 The fluorocarbon resin prepared in different embodiments 1 H NMR spectrum, where Figure 3 (c) The fluorocarbon resin prepared in Example 5 1 H NMR spectrum, Figure 3 (d) The fluorocarbon resin prepared in Example 6 1 H NMR spectra;

[0032] Figure 4 The GPC diagrams of fluorocarbon resins prepared in different embodiments are shown below: Figure 4(a) is the GPC chart of the fluorocarbon resin prepared in Example 1, Figure 4 (b) is the GPC chart of the fluorocarbon resin prepared in Example 5, Figure 4 (c) is the GPC chart of the fluorocarbon resin prepared in Example 7;

[0033] Figure 5 The DSC diagrams of fluorocarbon resins prepared in different embodiments are shown below: Figure 5 (a) is the DSC graph of the fluorocarbon resin prepared in Example 1, Figure 5 (b) is the DSC graph of the fluorocarbon resin prepared in Example 5. DETAILED DESCRIPTION

[0034] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0036] source:

[0037] Unless otherwise specified, the reagents, materials, and equipment used in this example are all commercially available; the experimental methods are all conventional experimental methods in the art unless otherwise specified.

[0038] Example 1

[0039] A fluorocarbon resin having a block copolymer.

[0040] In the cationic polymerization method, tin tetrachloride (SnCl4) was used as a catalyst, fluorostyrene (FS) and divinylbenzene (DVB) were used as reaction monomers to synthesize the block copolymer FS-co-DVB.

[0041] In this embodiment, the specific preparation method is as follows:

[0042] Weigh 0.733g (6mmol) of fluorostyrene (fluorinated monomer) and 7ml of dichloromethane (solvent) into a three-necked flask, inject 0.07ml (0.6mmol) of SnCl4 (catalyst), and react at 0℃ for 1h. Then, take a small amount of the reaction solution and drop it into methanol to observe whether there is precipitation. After confirming that polyfluorostyrene is produced, add 3ml of toluene (dry, solvent) and 1.56g (12mmol) of divinylbenzene (polymerization monomer), and continue to react at 0℃ for 2h.

[0043] Then, sampling and analysis confirmed that divinylbenzene was copolymerized. Next, the reaction solution was precipitated in 10 times the amount of methanol to obtain a white powder. The product was vacuum dried and weighed to measure the yield, which was about 66%.

[0044] Divinylbenzene can be used as a reagent with a mass concentration of 55% to 80%. In this embodiment, the mass concentration of the divinylbenzene reagent used is 55wt%; the molar ratio of the fluorine-containing monomer, the polymerization monomer, and the catalyst is 10:20:1.

[0045] The chemical reaction formula of this embodiment is as follows Figure 1 (a) shows that fluorocarbon resin 1 H NMR images Figure 2 (a) shows the GPC diagram of fluorocarbon resin. Figure 4 (a) shows the DSC diagram of fluorocarbon resin. Figure 5 (a) shown.

[0046] Example 2

[0047] A fluorocarbon resin.

[0048] In this embodiment, the specific preparation method is as follows:

[0049] Weigh 2 ml (14.5 mmol) of pentafluorostyrene (fluorinated monomer), 0.028 ml (0.205 mmol) of benzyl bromide (free radical initiator), 0.0294 g (0.205 mmol) of copper (I) bromide (catalyst) and 0.064 g (0.41 mmol) of 2,2'-bipyridine (catalyst) in a three-necked flask and react at 110°C for 100 min.

[0050] Then, 8 times the amount of dichloromethane was added to shake and dissolve the green viscous solid. Then, it was precipitated dropwise in 10 times the amount of methanol, and after decantation and gravity filtration, the solvent was drained with a vacuum pump to obtain a white solid, which was weighed and measured to obtain a homopolymer of pentafluorostyrene with a yield of about 83%.

[0051] In this example, the inventors explored the polymerization conditions that can obtain a homopolymer of pentafluorostyrene, and subsequent experiments further conducted copolymerization with divinylbenzene.

[0052] Example 3

[0053] A fluorocarbon resin.

[0054] In this embodiment, the specific preparation method is as follows:

[0055] 0.068 g (0.4 mmol) of benzyl bromide (free radical initiator), 0.057 g (0.4 mmol) of copper (I) bromide (catalyst), 0.1874 g (1.2 mmol) of 2,2'-bipyridine (catalyst) and 1.716 g (6 mmol) of octafluoropentyl acrylate (fluorinated monomer) were weighed into a three-necked flask and reacted at 110°C for 4 hours.

[0056] The reaction liquid changes from brown to green and becomes more viscous. After the reaction is completed, 5 ml of acetone is added, and the solid is filtered out and the reaction liquid is precipitated in 40 ml of hexane. The product is viscous and brown. After the solvent is drained with a vacuum pump, it is weighed and measured to obtain a homopolymer of octafluoropentyl acrylate with a yield of about 55.3%.

[0057] In this embodiment, the inventors explored the polymerization conditions that can obtain the homopolymer of octafluoropentyl acrylate, and further copolymerized it with divinylbenzene in subsequent experiments.

[0058] Example 4

[0059] A fluorocarbon resin having a block copolymer.

[0060] In the atom transfer radical polymerization method, copper bromide / bipyridine (CuBr / Bipy) is used as a catalyst, benzyl bromide is used as a radical initiator, and fluorostyrene, pentafluorostyrene (PFS) or octafluoropentyl acrylate (OFE) and divinylbenzene are used as reaction monomers to synthesize block copolymers FS-co-DVB, PFS-co-DVB and OFE-co-DVB, respectively.

[0061] In this embodiment, the specific preparation method is as follows:

[0062] Weigh 0.014 ml (0.103 mmol) of benzyl bromide (free radical initiator), 0.0147 g (0.103 mmol) of copper (I) bromide (catalyst), 0.032 g (0.205 mmol) of 2,2'-bipyridine (catalyst) and 0.2 ml of xylene (solvent) in a three-necked flask, react at 50°C for 30 min, then add 1 ml (8.38 mmol) of fluorostyrene (fluorinated monomer), raise the reaction temperature to 100°C, and continue the reaction for 70 min.

[0063] At this time, a small amount of the reaction solution was dropped into methanol to observe whether there was precipitation. After confirming the generation of polyfluorostyrene, 0.945g (7.25mmol) of divinylbenzene (polymerization monomer) and 0.5ml of xylene (solvent) were added, the reaction temperature was raised to 120°C, and the reaction was continued for 130min. After the reaction was completed, sampling and analysis were performed to confirm that divinylbenzene was copolymerized. The reaction solution was precipitated in 10 times the amount of methanol, and after decantation and gravity filtration, the solvent was drained with a vacuum pump to obtain a white powder, which was weighed and measured to obtain the target product with a poor yield.

[0064] Divinylbenzene can be used as a reagent with a mass concentration of 55% to 80%. In this embodiment, the mass concentration of the divinylbenzene reagent used is 55wt%; the molar ratio of the fluorinated monomer, the polymerization monomer, the free radical initiator, copper bromide, and bipyridine is 81.36:70.39:1:1:2.

[0065] The chemical reaction formula of this embodiment is as follows Figure 1 (b) shows that fluorocarbon resin 1 HNMR Figure 2 As shown in (b), the results show that the characteristic absorption peaks of 6.75 and 6.4 ppm (a, b) of the polymer side chain of p(FS-co-DVB) after polymerization belong to the hydrogen atoms on fluorostyrene, while the characteristic absorption peaks of 5.71 and 5.21 ppm belong to the hydrogen atoms on the double bond of divinylbenzene. It can be determined that p(FS-co-DVB) was successfully synthesized.

[0066] Example 5

[0067] A fluorocarbon resin having a block copolymer.

[0068] In the atom transfer radical polymerization method, copper bromide / bipyridine (CuBr / Bipy) is used as a catalyst, benzyl bromide is used as a radical initiator, and fluorostyrene, pentafluorostyrene (PFS) or octafluoropentyl acrylate (OFE) and divinylbenzene are used as reaction monomers to synthesize block copolymers FS-co-DVB, PFS-co-DVB and OFE-co-DVB, respectively.

[0069] In this embodiment, the specific preparation method is as follows:

[0070] Weigh 2 ml (14.5 mmol) of pentafluorostyrene (fluorinated monomer), 0.028 ml (0.205 mmol) of benzyl bromide (free radical initiator), 0.0294 g (0.205 mmol) of copper bromide (Ⅰ) (catalyst) and 0.064 g (0.41 mmol) of 2,2'-bipyridine (catalyst) in a three-necked flask, react at 110°C for 60 min, add 1.89 g (14.5 mmol) of divinylbenzene (polymerizable monomer) and 1 ml of xylene (solvent), heat to 130-140°C, and continue to react for 140 min.

[0071] When the reaction liquid is observed to be viscous and without transparent layers, the reaction temperature is cooled to room temperature, and the reaction liquid is shaken and dissolved with 70 ml of dichloromethane, and filtered into a conical flask. Then, the dichloromethane layer is extracted with 1 ml of HCl (0.37%) and 100 ml of water, and extracted twice with 100 ml of deionized water until neutral, and the dichloromethane layer is taken and dried with anhydrous magnesium sulfate, and then filtered into a flask, and the dichloromethane is drained with a rotary concentrator and a high-pressure pump, and then weighed and measured.

[0072] Divinylbenzene can be used as a reagent with a mass concentration of 55% to 80%. In this embodiment, the mass concentration of the divinylbenzene reagent used is 80wt%; the molar ratio of the fluorinated monomer, the polymerization monomer, the free radical initiator, copper bromide, and bipyridine is 70.73:70.73:1:1:2.

[0073] The chemical reaction formula of this embodiment is as follows Figure 1 (c) shows that fluorocarbon resin 1 H NMR images Figure 3 (c) shows the GPC diagram of fluorocarbon resin. Figure 4 (b) shows the DSC diagram of fluorocarbon resin. Figure 5 (b) as shown.

[0074] Example 6

[0075] A fluorocarbon resin having a block copolymer.

[0076] In the atom transfer radical polymerization method, copper bromide / bipyridine (CuBr / Bipy) is used as a catalyst, benzyl bromide is used as a radical initiator, and fluorostyrene, pentafluorostyrene (PFS) or octafluoropentyl acrylate (OFE) and divinylbenzene are used as reaction monomers to synthesize block copolymers FS-co-DVB, PFS-co-DVB and OFE-co-DVB, respectively.

[0077] In this embodiment, the specific preparation method is as follows:

[0078] 0.034 g (0.2 mmol) of benzyl bromide (free radical initiator), 0.0285 g (0.2 mmol) of copper (I) bromide (catalyst), 0.0937 g (0.6 mmol) of 2,2'-bipyridine (catalyst), 0.858 g (3 mmol) of octafluoropentyl acrylate (fluorinated monomer) and 1.56 g (12 mmol) of divinylbenzene (polymerized monomer) were weighed and placed in a three-necked flask. After reacting at 100°C for 17 min, 1.56 g (12 mmol) of divinylbenzene (polymerized monomer) was added and the reaction was continued for 1.5 h.

[0079] The product was precipitated in 10 times the amount of methanol, filtered, the solvent was drained, weighed and measured to obtain the target product with a poor yield.

[0080] Divinylbenzene can be used as a reagent with a mass concentration of 55% to 80%. In this embodiment, the mass concentration of the divinylbenzene reagent used is 55wt%; the molar ratio of the fluorinated monomer, the polymerization monomer, the free radical initiator, copper bromide, and bipyridine is 15:60:1:1:3.

[0081] The chemical reaction formula of this embodiment is as follows Figure 1 As shown in (d), fluorocarbon resin 1 H NMR images Figure 3 (d) as shown.

[0082] Example 7

[0083] A fluorocarbon resin having a block copolymer.

[0084] In this embodiment, the fluorocarbon resin is prepared by cationic polymerization.

[0085] Weigh 0.733g (6mmol) of fluorostyrene (fluorinated monomer) and 7ml of dichloromethane (solvent) into a three-necked flask, inject 0.07ml (0.6mmol) of SnCl4 (catalyst), and react at 0℃ for 1h. Then, take a small amount of the reaction solution and drop it into methanol to observe whether there is precipitation. After confirming that polyfluorostyrene is produced, add 3ml of toluene (dry, solvent) and 1.56g (12mmol) of divinylbenzene (polymerization monomer), and continue to react at 0℃ for 1.5h.

[0086] Then, sampling and analysis confirmed that divinylbenzene was copolymerized. Next, the reaction solution was precipitated in 10 times the amount of methanol to obtain a white powder. The product was vacuum dried and weighed to measure the yield of about 54%.

[0087] Divinylbenzene can be used as a reagent with a mass concentration of 55% to 80%. In this embodiment, the mass concentration of the divinylbenzene reagent used is 55wt%; the molar ratio of the fluorine-containing monomer, the polymerization monomer, and the catalyst is 10:20:1.

[0088] Compared with Example 1, the reaction time after adding the polymerization monomer in Example 7 is shortened, and the yield of the fluorocarbon resin finally obtained is slightly reduced. In the cationic polymerization method, the extension of the reaction time may lead to an increase in molecular weight, but it may also introduce side reactions (such as chain transfer and chain termination reactions), which will limit the increase in molecular weight, and chain transfer reactions are the main factors controlling molecular weight. Therefore, compared with Example 7, Example 1 obtains a higher yield, and compared with the PDI of 2.8055 in Example 7, Example 1 also obtains a polymer with a narrower molecular weight distribution (PDI of 2.2301), so that the product molecular chain length tends to be consistent, forming a more uniform physical structure.

[0089] The GPC chart of the fluorocarbon resin prepared in this example is as follows: Figure 4 (c) as shown.

[0090] Example 8

[0091] A fluorocarbon resin having a block copolymer.

[0092] In this embodiment, the atom transfer radical polymerization method is specifically adopted for preparation.

[0093] Weigh 1 ml (7.25 mmol) of pentafluorostyrene (fluorinated monomer), 0.014 ml (0.103 mmol) of benzyl bromide (radical initiator), 0.0147 g (0.103 mmol) of copper bromide (I) (catalyst) and 0.064 g (0.205 mmol) of 2,2'-bipyridine (catalyst) in a three-necked flask. After reacting at 110°C for 70 min, add 0.945 g (7.25 mmol) of divinylbenzene (polymerizable monomer) and 0.5 ml of xylene (solvent), and continue to react at 110°C for 110 min.

[0094] The reaction solution obtained by the above reaction was shaken and dissolved in 3.5 ml of dichloromethane, and the filtrate after filtering through filter paper was dropwise precipitated in 10 times the amount of methanol, and after decantation and gravity filtration, the solvent was drained with a vacuum pump to obtain a white powder. The product was weighed, and the yield was about 52%.

[0095] Divinylbenzene can be used as a reagent with a mass concentration of 55% to 80%. In this embodiment, the mass concentration of the divinylbenzene reagent used is 55wt%; the molar ratio of the fluorinated monomer, the polymerization monomer, the free radical initiator, copper bromide, and bipyridine is 70.39:70.39:1:1:2.

[0096] Compared with Example 5, the mass concentration of divinylbenzene used in Example 8 is 55wt%, while the mass concentration of divinylbenzene used in Example 5 is 80wt%, which is equivalent to a 1-fold increase in the amount of reaction monomers, catalysts, and solvents. The purpose is to increase the yield of p(PFS-co-DVB), but the results of Example 5 show that compared with Example 8, the yield is not significantly improved, and a lot of DVB monomer remains, which indicates that the reactivity of DVB is not high in this stage of copolymerization.

[0097] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A fluorocarbon resin having a block copolymer, characterized in that: The fluorocarbon resin is prepared by cationic polymerization or atom transfer free radical polymerization, and the reaction raw materials include fluorine-containing monomers; The fluorine-containing monomer includes at least one of pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate.

2. The fluorocarbon resin according to claim 1, characterized in that The structural formula of the fluorocarbon resin is shown in any one of Formulas 1-4: Formula 1: Formula 2: Formula 3: Formula 4:

3. The fluorocarbon resin according to any one of claims 1 to 2, characterized in that The weight average molecular weight M of the fluorocarbon resin w It is 13000~18000, and the glass transition temperature is ≥80℃.

4. The method for preparing the fluorocarbon resin according to any one of claims 1 to 3, characterized in that: The reaction raw materials are prepared into fluorocarbon resin by cationic polymerization or atom transfer radical polymerization, and the reaction raw materials include fluorine-containing monomers; The fluorine-containing monomer includes at least one of pentafluorostyrene, fluorostyrene or octafluoropentyl acrylate.

5. The preparation method according to claim 4, characterized in that: The cationic polymerization method comprises the following steps: dissolving a fluorine-containing monomer to obtain a fluorine-containing monomer solution, dissolving a polymerizable monomer to obtain a polymerizable monomer solution, adding a catalyst to the fluorine-containing monomer solution, reacting at a temperature of (-1°C) to 0°C for 0.8 to 1.2 hours, adding the polymerizable monomer solution, reacting at a temperature of (-1°C) to 0°C for 1.5 to 2 hours, and obtaining a fluorocarbon resin; The fluorine-containing monomer includes fluorostyrene, the polymerizable monomer includes divinylbenzene, and the catalyst includes tin tetrachloride; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, and the catalyst is (8-12): (18-22): (0.8-1.2).

6. The preparation method according to claim 4, characterized in that: The atom transfer radical polymerization method comprises the following steps: mixing a fluorine-containing monomer, a free radical initiator, a catalyst, and a solvent, reacting at a temperature of 100° C. to 110° C. for 10 to 250 minutes, adding a polymerization monomer, heating to 100° C. to 140° C., and reacting for 80 to 140 minutes to obtain a fluorocarbon resin; The free radical initiator includes benzyl bromide, and the catalyst includes copper bromide and bipyridine.

7. The preparation method according to claim 6, characterized in that: The fluorine-containing monomer includes fluorostyrene, and the polymerizable monomer includes divinylbenzene; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, the free radical initiator, copper bromide, and bipyridine is (78-84): (68-72): (0.8-1.2): (0.8-1.2): (1.8-2.2).

8. The preparation method according to claim 6, characterized in that: The fluorine-containing monomer includes pentafluorostyrene, and the polymerizable monomer includes divinylbenzene; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, the free radical initiator, copper bromide, and bipyridine is (68-72): (68-72): (0.8-1.2): (0.8-1.2): (1.8-2.2).

9. The preparation method according to claim 6, characterized in that: The fluorine-containing monomer includes octafluoropentyl acrylate, and the polymerizable monomer includes divinylbenzene; the molar ratio of the fluorine-containing monomer, the polymerizable monomer, the free radical initiator, copper bromide, and bipyridine is (13-17): (58-62): (0.8-1.2): (0.8-1.2): (2.8-3.2).

10. Use of the fluorocarbon resin according to any one of claims 1 to 3 or the fluorocarbon resin obtained by the preparation method according to any one of claims 4 to 9 in building materials, chemical materials and electronic materials.

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