Method for synthesizing hexafluoropropylene oxidation-based perfluoropolyether multifunctional end group modified material by one-step method

Abstract

The invention discloses a method for synthesizing a hexafluoropropylene oxidation-based perfluoropolyether multifunctional end group modified material by a one-step method. The method comprises the following steps: 1, firstly, generating an acyl fluoride end group perfluoropolyether intermediate from hexafluoropropylene in a photo-oxidation manner; 2, introducing an enamine co-reactant to carry out cascade reaction to form a perfluoropolyether intermediate for further functional group modification; and 3, simultaneously carrying out peroxy bond breakage and diene amine introduction, carrying out an addition reaction on amino groups and unsaturated bonds in the perfluoropolyether intermediate under light irradiation, and simultaneously carrying out peroxy removal on perfluoropolyether under the catalytic action of a photocatalyst so as to obtain a perfluoropolyether final product. And 4, terminal group multifunctional modification: introducing the anti-fingerprint coating into a perfluoropolyether end product in one-step reaction, and then carrying out purification and function test. The perfluoropolyether material with excellent performance is prepared by integrating the photooxidation reaction and the end group modification process of hexafluoropropylene and simultaneously realizing the introduction of groups in a one-step process.

Description

Technical Field

[0001] The present invention relates to a method for synthesizing a perfluoropolyether multifunctional end-group modified material, in particular to a method for synthesizing a perfluoropolyether multifunctional end-group modified material based on the oxidation of hexafluoropropene by a one-step method. Background Art

[0002] With the wide application of high-tech materials in the fields of electronics, smart home, automobiles, etc., the demand for functional materials with excellent surface properties is increasing day by day. Especially in the development of multifunctional materials such as fingerprint-proof, antibacterial, and anti-ultraviolet, how to achieve multifunctional integration through an efficient synthesis process has become one of the key research topics in materials science. At present, perfluoropolyether (PFPE) has been widely used in the preparation of special coatings and composite materials due to its excellent chemical resistance, low surface energy, and excellent lubricating properties, and has received great attention especially in the field of anti-fingerprint coatings (AF).

[0003] The preparation of traditional perfluoropolyether functional materials is generally carried out through multiple steps, including first synthesizing the polymer backbone and then introducing functional groups through further end-group modification. However, this multi-step process has problems such as complex process flow, long reaction time, and high energy consumption, and it is difficult to meet the requirements of large-scale industrial production. Especially when multiple functions (such as fingerprint-proof, antibacterial, and anti-ultraviolet) need to be combined, the complexity and cost of the process are further increased. Therefore, how to simplify the process flow and improve the synthesis efficiency has become the key to the development of multifunctional perfluoropolyether materials. Summary of the Invention

[0004] The present invention provides a method for synthesizing a perfluoropolyether multifunctional end-group modified material based on the oxidation of hexafluoropropene by a one-step method, which integrates the photooxidation reaction of hexafluoropropene and the end-group modification process, and simultaneously introduces groups in a one-step process to prepare a perfluoropolyether material with excellent performance.

[0005] The present invention adopts the following technical solutions: A method for synthesizing a perfluoropolyether multifunctional end-group modified material based on the oxidation of hexafluoropropene by a one-step method, which includes the following steps:

[0006] A method for synthesizing a perfluoropolyether multifunctional end-group modified material based on the oxidation of hexafluoropropene by a one-step method, which includes the following steps:

[0007] Step 1, first generate a perfluoropolyether intermediate with an acyl fluoride end group from hexafluoropropene through a photooxidation method, that is, intermediate I;

[0008] Step 2, introduce an enamine co-reactant for a tandem reaction: By controlling the reaction conditions, directly introduce an enamine co-reactant to carry out an imidation reaction with the acyl fluoride end group of the acyl fluoride intermediate in Step 1 to form a perfluoropolyether intermediate for further functional group modification, that is, intermediate II:

[0009]

[0010] Step 3, simultaneously perform peroxy bond cleavage and introduction of dienamine: Use a photocatalyst at an appropriate temperature to induce the cleavage of the peroxy bond in the system, generating a radical reaction. At the same time, introduce dienamine, and allow its amino group to undergo an addition reaction with the unsaturated bond in the perfluoropolyether intermediate under light irradiation. Meanwhile, under the catalysis of the photocatalyst, the perfluoropolyether is deperoxidized to obtain the perfluoropolyether end product;

[0011] Step 4, end-group multi-functional modification: Through end-group modification, introduce an anti-fingerprint coating into the perfluoropolyether end product in one-step reaction, and then carry out purification and functional testing.

[0012] Furthermore, in the method of photooxidation described in Step 1, the molar ratio of hexafluoropropene to oxygen is between 1:1 and 1:10, the reaction temperature is -60 to 10 °C, hexafluoropropene and oxygen are oxidized to form an acyl fluoride intermediate under ultraviolet light irradiation, and the wavelength of the ultraviolet light is 230 to 270 nm.

[0013] Furthermore, the conditions for the tandem reaction in Step 2 are a reaction temperature of -20 to 25 °C, a reaction time of 10 to 60 min, and the mono-eneamine co-reactant is an ene-amine co-reactant, and the ene-amine co-reactant is allylamine.

[0014] Furthermore, in Step 3, the dienamine is diallylamine, the photocatalyst is a titanate or a visible photosensitizer, and the concentration of the photocatalyst is 0.1 to 3 mol%.

[0015] Furthermore, in Step 3, the light irradiation is carried out using an ultraviolet lamp.

[0016] The present invention has the following beneficial effects: After adopting the above technical solutions, the present invention aims to integrate the photooxidation reaction of hexafluoropropylene and the end-group modification process, introduce multifunctional groups simultaneously in a one-step process, synchronously perform deperoxidation and the introduction of enamine, and develop a perfluoropolyether material with excellent surface properties. The preparation method of the present invention not only significantly shortens the reaction time, improves the efficiency, simplifies the operation process, synthesizes efficiently by the continuous method, reduces the use of solvents, but also reduces environmental pollution and energy consumption through a green process, and has high industrialization potential. By introducing photocatalytic technology and controlling the co-reactants, the present invention can directly introduce multifunctional groups during the photooxidation process to achieve the multiple functionalization of perfluoropolyether. By regulating the end groups, the functionalized products are suitable for fields such as flexible electronic screens, automotive coatings, and smart homes. The dienamine of the present invention is diallylamine, which undergoes an addition reaction with the unsaturated bonds in the perfluoropolyether, thus enhancing the weather resistance of the product. The concentration, reaction temperature, and reaction time of the photocatalyst of the present invention are adjustable, which can control the selectivity of the reaction and improve the yield of the product. By modulating the intensity of the incident light, the molecular weight distribution of the final product can be controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1 It is the preparation flow chart of the embodiment of the present invention.

[0019] Figure 2 It is the relationship diagram between the contact angle and the number of friction times in Embodiment 1 of the present invention.

[0020] Figure 3 It is the relationship diagram between the contact angle and the number of friction times in Embodiment 2 of the present invention.

[0021] Figure 4 It is the relationship diagram between the contact angle and the number of friction times in Embodiment 3 of the present invention.

[0022] Figure 5 It is the relationship diagram between the contact angle and the number of friction times in Embodiment 4 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following will elaborate on the preferred embodiments of the present invention in conjunction with the drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0024] The present invention provides a method for one-step synthesis of a perfluoropolyether multifunctional end-group modified material based on hexafluoropropylene oxidation, which comprises the following steps:

[0025] Step 1: First, generate a perfluoropolyether intermediate with an acyl fluoride end group, namely Intermediate I, by photo-oxidizing hexafluoropropylene. In the photo-oxidation method described in Step 1 of the present invention, the molar ratio of hexafluoropropylene to oxygen is between 1:1 and 1:10, the reaction temperature is -60 to 10 °C, and hexafluoropropylene and oxygen are oxidized under ultraviolet light irradiation to generate an acyl fluoride intermediate. The wavelength of the ultraviolet light is 230 to 270 nm.

[0026] Step 2: Introduce an enamine co-reactant for a tandem reaction: By controlling the reaction conditions, directly introduce an enamine co-reactant to carry out an imidization reaction with the acyl fluoride end group of the acyl fluoride intermediate in Step 1 to form a perfluoropolyether intermediate for further functional group modification, namely Intermediate II.

[0027]

[0028] In the present invention, the conditions for the tandem reaction in Step 2 are: the reaction temperature is -20 to 25 °C, the reaction time is 10 to 60 min, the enamine co-reactant is an enamine-based co-reactant, and the enamine-based co-reactant is allylamine.

[0029] Step 3: Simultaneously break the peroxy bond and introduce a dieneamine: Use a photocatalyst at an appropriate temperature to induce the breakage of the peroxy bond in the system to generate a radical reaction, and at the same time introduce a dieneamine, so that the amino group thereof undergoes an addition reaction with the unsaturated bond in the perfluoropolyether intermediate under light irradiation. At the same time, the perfluoropolyether is de-peroxidized under the catalysis of the photocatalyst to obtain a perfluoropolyether end product. In Step 3, the dieneamine is diallylamine, the photocatalyst is a titanate or a visible photosensitizer, the concentration of the photocatalyst is 0.1 to 3 mol%, and the light irradiation is carried out using an ultraviolet lamp.

[0030] Step 4: Multifunctional end-group modification: Through end-group modification, introduce an anti-fingerprint coating into the perfluoropolyether end product in a one-step reaction, and then carry out purification and functional testing.

[0031] The following further illustrates the preparation process of the present invention through examples.

[0032] Example 1, Step 1, Photooxidation of hexafluoropropene to form acyl fluoride intermediate: Prepare a sealed 2L vacuum tube reactor I with continuous feeding and discharging functions. The pressure resistance of the vacuum tube reactor I is 1.5 MPa, and it is equipped with an on-line temperature and pressure control system. The on-line temperature and pressure control system is an integrated automatic control system that can monitor and adjust the temperature and pressure inside the reactor in real time to ensure the stability and safety of the reaction conditions. This system usually includes a temperature sensor and a pressure sensor. The temperature sensor is a thermocouple or an RTD sensor, and the pressure sensor is a pressure transmitter. The temperature sensor and the pressure sensor feedback the temperature and pressure data inside the reactor in real time, and through a temperature control instrument, that is, a PID controller, automatically adjust the heating or cooling equipment to maintain the set temperature range. The pressure control system automatically adjusts the gas flow rate and the composition of the reaction gas through a pressure regulating valve and a gas delivery system to ensure that the internal pressure of the reactor is stable within a predetermined range. The entire system is integrated by a PLC controller to automatically adjust each link to ensure the ideal conditions of the reaction process. At the same time, in case of an abnormality, a warning is given through an alarm system and safety measures are taken. An ultraviolet light source with adjustable wavelength and a gas delivery system store hexafluoropropene in a gas storage tank and connect it to the feeding port of the vacuum tube reactor I. Set the flow rate of hexafluoropropene to 12 g / min. The oxygen storage tank is also connected to the feeding port of the vacuum tube reactor I. In the photooxidation method, the molar ratio of hexafluoropropene to oxygen is between 1:5, and the reaction temperature is -60 to 10 °C. The reaction temperature in this example is 10 °C. Set the flow rate to 0.32 g / min, keep the internal temperature of the vacuum tube reactor I within the range of 0-10 °C, turn on the ultraviolet lamp, set the wavelength of the incident ultraviolet light to 254 nm, and monitor the pressure and temperature inside the reactor in real time through an on-line sensor to ensure the stable operation of the system. Discharge once every 15 minutes from the discharge port, and the discharge is directly transported to storage tank I through a PTFE hose. The volume of storage tank I is 20 L. Regularly sample from the reactor discharge port through an on-line sampling system by a precisely controlled pump or valve. The collected samples are analyzed by a molecular weight distribution analyzer through gel permeation chromatography, gas chromatography, and high performance liquid chromatography to determine the molecular weight distribution and the ratio of single-end and double-end acyl fluoride compounds. The analysis results are fed back to the data acquisition system in real time to provide a basis for the control system to automatically adjust the reaction conditions, such as temperature, pressure, gas flow rate, etc., to ensure that the molecular weight range and composition of the intermediate meet the expectations and guarantee the stability of the reaction and the product quality. Detect the perfluoropolyether intermediate in the discharge, that is, the molecular weight distribution of intermediate I is 3200-3500 g / mol, of which the single-end acyl fluoride perfluoropolyether compound accounts for 92%, and the double-end acyl fluoride compound accounts for about 8%. The chemical equation of the reaction is:

[0033]

[0034] Step 2, introducing allylamine for addition reaction: Based on the molecular weight of the perfluoropolyether acyl fluoride prepared in Step 1 being 3350 g / mol, 335 g (0.1 mol) of Intermediate I is directly transported from Storage Tank I to Reactor II. 6.85 g of allylamine is dissolved in 20 g of 7200 electronic fluorination liquid, and then it is added dropwise to Reactor II by a metering pump within 10 minutes for imidization reaction. The reaction temperature is controlled at about 0 °C, and the reaction is stirred for 30 min. After the reaction, Intermediate II is obtained. The chemical equation of the reaction is:

[0035]

[0036] Step 3, synchronously removing peroxide and introducing diallylamine: Intermediate II in Reactor II is further transported to Reactor III by a PTFE hose. Reactor III is also a vacuum tube reactor. The temperature inside Reactor III is continuously maintained at 0 - 10 °C. The wavelength of the ultraviolet lamp is set to 185 nm. 1 mol‰ of the photocatalyst titanate based on the amount of Intermediate II and 0.12 mol of diallylamine are dispersed in 20 g of 7200 solution. The amount of titanate is 1 mol‰ of Intermediate II and is added dropwise to Reactor III by a metering pump within 10 min. Under the irradiation of ultraviolet light, the double bond of Intermediate II is activated and can undergo a high-efficiency addition reaction with diallylamine; at the same time, under the catalytic action of titanate, the perfluoropolyether chain segment completes peroxide removal. The perfluoropolyether end product can be obtained in this step. The chemical equation of the reaction is:

[0037]

[0038] Step 4, reacting with trimethoxysilane

[0039] After the addition reaction of diallylamine in Step 3 is completed, the ultraviolet lamp is turned off, and the temperature of the system is raised to room temperature. 0.24 mol of trimethoxysilane and the catalyst RuCl2(NHC)(PPh3) (the amount used is 2 mol‰ of Intermediate II) are added dropwise to the reactor by a metering pump to modify the end groups of the perfluoropolyether end product. The reaction is continuously stirred for 30 min to obtain the perfluoropolyether anti-fingerprint agent SY1-6 containing 6 methoxy groups and a small amount of DY1-6, thereby introducing the anti-fingerprint coating into the perfluoropolyether end product. The chemical equation of the reaction is:

[0040]

[0041] Step 5, purification: After filtration, the low-boiling reactants and solvents are removed by rotary evaporation, and then SY1-6 and DY1-6 are separated by molecular distillation;

[0042] Step 6, Testing: Spray the 7200 solutions of 4‰ SY1-6 and DY1-6 onto the surface of a glass plate, and conduct hydrophobic and wear-resistant tests on the formed coating. The contact angle data are shown in Figure 1 .

[0043] Example 2, Step 1, Photooxidation of hexafluoropropylene to generate an acyl fluoride intermediate: Prepare a closed 2L vacuum tube reactor I with continuous feeding and discharging functions. The pressure resistance of the vacuum tube reactor I is 1.5 MPa, and it is equipped with an on-line temperature and pressure control system. The on-line temperature and pressure control system is an integrated automatic control system that can monitor and adjust the temperature and pressure inside the reactor in real time to ensure the stability and safety of the reaction conditions. This system usually includes a temperature sensor and a pressure sensor. The temperature sensor is a thermocouple or an RTD sensor, and the pressure sensor is a pressure transmitter. The temperature sensor and the pressure sensor real-time feedback the temperature and pressure data inside the reactor, and through a temperature control instrument, that is, a PID controller, automatically adjust the heating or cooling equipment to maintain the set temperature range. The pressure control system automatically adjusts the gas flow rate and the composition of the reaction gas through a pressure regulating valve and a gas delivery system to ensure that the pressure inside the reactor is stably within a predetermined range. The entire system is integrated by a PLC controller, automatically adjusting each link to ensure the ideal conditions of the reaction process. At the same time, in case of an abnormality, it gives an early warning through an alarm system and takes safety measures. An ultraviolet light source with adjustable wavelength and a gas delivery system are used. Store hexafluoropropylene in a gas storage tank and connect it to the feed port of the vacuum tube reactor I. Set the flow rate of hexafluoropropylene to 12 g / min. The oxygen storage tank is also connected to the feed port of the vacuum tube reactor I, and the flow rate is set to 0.32 g / min. Keep the internal temperature of the vacuum tube reactor I within the range of 0-10 °C, turn on the ultraviolet lamp, and set the light wavelength of the incident ultraviolet light to 254 nm. Real-time monitor the pressure and temperature inside the reactor through on-line sensors to ensure the stable operation of the system. Discharge from the discharge port once every 8 minutes, and the discharge is directly transported to storage tank I through a PTFE hose. The volume of storage tank I is 20 L. Regularly sample from the reactor discharge port through an on-line sampling system with a precisely controlled pump or valve. The collected samples are analyzed by a molecular weight distribution analyzer through gel permeation chromatography, gas chromatography, and high performance liquid chromatography to determine the molecular weight distribution and the ratio of single-end and double-end acyl fluoride compounds. The analysis results are real-time fed back to the data acquisition system to provide a basis for the control system, and automatically adjust the reaction conditions, such as temperature, pressure, gas flow rate, etc., to ensure that the molecular weight range and composition of the intermediate meet the expectations, guarantee the stability of the reaction and the product quality. Detect the perfluoropolyether intermediate in the discharge, that is, the molecular weight distribution of intermediate I is 1500-2000 g / mol, among which the single-end acyl fluoride perfluoropolyether compound accounts for 95%, and the double-end acyl fluoride compound accounts for about 5%. The chemical equation of the reaction is:

[0044]

[0045] Step 2: Introduce allylamine for addition reaction: Based on the molecular weight of 1850 g / mol of the perfluoropolyether acyl fluoride prepared in Step 1, 335 g (0.1 mol) of Intermediate I is directly transported from Storage Tank I to Reactor II. Dissolve 6.85 g of allylamine in 20 g of 7200 solution, and then add it dropwise to Reactor II through a metering pump within 10 minutes for imidization reaction. Control the reaction temperature at about 0 °C and stir the reaction for 30 min. After the reaction, Intermediate II is obtained. The chemical equation of the reaction is as follows:

[0046]

[0047] Step 3: Synchronously remove peroxide and introduce diallylamine: Transport Intermediate II in Reactor II to Reactor III through a PTFE hose. Reactor III is also a vacuum tube reactor. Keep the temperature in Reactor III at 0 - 10 °C. Set the wavelength of the ultraviolet lamp to 185 nm. Disperse 1 mol‰ of the photocatalyst titanate based on the amount of Intermediate II and 0.12 mol of diallylamine in 20 g of 7200 solution. The amount of titanate is 1 mol‰ of Intermediate II. Add it dropwise to Reactor III through a metering pump within 10 min. Under the irradiation of ultraviolet light, the double bond of Intermediate II is activated and can undergo a highly efficient addition reaction with diallylamine; at the same time, under the catalysis of titanate, the perfluoropolyether chain segment completes peroxide removal. The perfluoropolyether end product can be obtained in this step. The chemical equation of the reaction is as follows:

[0048]

[0049] Step 4: React with trimethoxysilane

[0050] After the addition reaction of diallylamine in Step 3 is completed, turn off the ultraviolet lamp, raise the system temperature to room temperature, and add 0.24 mol of trimethoxysilane and 2 mol‰ of the catalyst RuCl2(NHC)(PPh3) based on the amount of Intermediate II dropwise to the reactor through a metering pump to perform end-group modification on the perfluoropolyether end product. Continue to stir the reaction for 30 min to obtain the perfluoropolyether anti-fingerprint agent SY1-6 containing 6 methoxy groups and a small amount of DY1-6, thereby introducing the anti-fingerprint coating into the perfluoropolyether end product. The chemical equation of the reaction is as follows:

[0051]

[0052] Step 5: Filter, rotary evaporate to remove low-boiling reactants and solvents, and then separate SY2-6 and DY2-6 by molecular distillation.

[0053] Step 6, Testing: Spray a 7200 solution of 4‰ SY1-6 and DY1-6 onto the surface of a glass plate, and conduct hydrophobic and wear-resistant tests on the formed coating. The contact angle data are shown in Figure 2 .

[0054] Example 3, Step 1, Photooxidation of hexafluoropropylene to form an acyl fluoride intermediate: Prepare a closed 2L vacuum tube reactor I with continuous feeding and discharging functions. The pressure resistance of the vacuum tube reactor I is 1.5 MPa, and it is equipped with an on-line temperature and pressure control system. The on-line temperature and pressure control system is an integrated automated control system that can monitor and adjust the temperature and pressure inside the reactor in real time to ensure the stability and safety of the reaction conditions. This system usually includes a temperature sensor and a pressure sensor. The temperature sensor is a thermocouple or an RTD sensor, and the pressure sensor is a pressure transmitter. The temperature sensor and the pressure sensor real-time feedback the temperature and pressure data inside the reactor, and through a temperature control instrument, that is, a PID controller, automatically adjust the heating or cooling equipment to maintain the set temperature range. The pressure control system automatically adjusts the gas flow rate and the composition of the reaction gas through a pressure regulating valve and a gas delivery system to ensure that the internal pressure of the reactor is stable within a predetermined range. The entire system is integrated by a PLC controller, automatically adjusting each link to ensure the ideal conditions of the reaction process. At the same time, in case of an abnormality, it issues a warning through an alarm system and takes safety measures. An ultraviolet light source with adjustable wavelength and a gas delivery system are used. Store hexafluoropropylene in a gas storage tank and connect it to the feed port of the vacuum tube reactor I. Set the flow rate of hexafluoropropylene to 12 g / min. The oxygen storage tank is also connected to the feed port of the vacuum tube reactor I, and the flow rate is set to 0.32 g / min. Keep the internal temperature of the vacuum tube reactor I within the range of 0-10 °C, turn on the ultraviolet lamp, and set the wavelength of the incident ultraviolet light to 290 nm. Real-time monitor the pressure and temperature inside the reactor through on-line sensors to ensure the stable operation of the system. Discharge from the discharge port once every 8 minutes, and the discharge is directly transported to storage tank I through a PTFE hose. The volume of storage tank I is 20 L. Regularly sample from the reactor discharge port through an on-line sampling system with a precisely controlled pump or valve. The collected samples are analyzed by a molecular weight distribution analyzer through gel permeation chromatography, gas chromatography, and high performance liquid chromatography to determine the molecular weight distribution and the ratio of mono-terminal and di-terminal acyl fluoride compounds. The analysis results are real-time fed back to the data acquisition system to provide a basis for the control system to automatically adjust the reaction conditions, such as temperature, pressure, gas flow rate, etc., to ensure that the molecular weight range and composition of the intermediate meet the expectations, and ensure the stability of the reaction and the product quality. Detect the perfluoropolyether intermediate in the discharge, that is, the molecular weight distribution of intermediate I is 1100-1400 g / mol, where the mono-terminal acyl fluoride perfluoropolyether compound accounts for 95%, and the di-terminal acyl fluoride compound accounts for about 5%. The chemical equation of the reaction is:

[0055]

[0056] Step 2: Introduce allylamine for addition reaction: Based on the molecular weight of the perfluoropolyether acyl fluoride prepared in Step 1 being 1350 g / mol, 335 g (0.1 mol) of Intermediate I is directly transported from Storage Tank I to Reactor II. Dissolve 6.85 g of allylamine in 20 g of 7200 solution, and then add it dropwise to Reactor II within 10 minutes by a metering pump for imidization reaction. Control the reaction temperature at about 0 °C and stir the reaction for 30 min. After the reaction, Intermediate II is obtained. The chemical equation of the reaction is:

[0057]

[0058] Step 3: Synchronously remove peroxide and introduce diallylamine: Transport Intermediate II in Reactor II to Reactor III through a PTFE hose. Reactor III is also a vacuum tube reactor. Keep the temperature in Reactor III at 0 - 10 °C. Set the wavelength of the ultraviolet lamp to 185 nm. Disperse 1 mol‰ of the photocatalyst titanate based on the amount of Intermediate II and 0.12 mol of diallylamine in 20 g of 7200 solution. The amount of titanate is 1 mol‰ of Intermediate II. Add it dropwise to Reactor III within 10 min by a metering pump. Under the irradiation of ultraviolet light, the double bond of Intermediate II is activated and can undergo a highly efficient addition reaction with diallylamine; meanwhile, under the catalytic action of titanate, the perfluoropolyether chain segment completes peroxide removal. The perfluoropolyether end product can be obtained in this step. The chemical equation of the reaction is:

[0059]

[0060] Step 4: React with trimethoxysilane

[0061] After the addition reaction of diallylamine in Step 3 is completed, turn off the ultraviolet lamp, raise the system temperature to room temperature, and add 0.24 mol of trimethoxysilane and the catalyst RuCl2(NHC)(PPh3) (the amount is 2 mol‰ of Intermediate II) dropwise to the reactor by a metering pump to modify the end groups of the perfluoropolyether end product. Continue to stir the reaction for 30 min to obtain the perfluoropolyether anti-fingerprint agent SY1-6 containing 6 methoxy groups and a small amount of DY1-6, thereby introducing the anti-fingerprint coating into the perfluoropolyether end product. The chemical equation of the reaction is:

[0062]

[0063] Step 5: Filter, rotary evaporate to remove low-boiling reactants and solvents, and then separate SY1-6 and DY1-6 by molecular distillation.

[0064] Step 6, Testing: Spray the 7200 solutions of SY3-6 and DY3-6 at 4‰ onto the surface of a glass plate, and conduct hydrophobic and wear-resistant tests on the formed coating. The contact angle data are shown in Figure 3 .

[0065] Example 4, Step 1, Photooxidation of hexafluoropropylene to form an acyl fluoride intermediate: Prepare a closed 2L vacuum tube reactor I with continuous feeding and discharging functions. The pressure resistance of the vacuum tube reactor I is 1.5 MPa, and it is equipped with an on-line temperature and pressure control system. The on-line temperature and pressure control system is an integrated automated control system that can monitor and adjust the temperature and pressure inside the reactor in real time to ensure the stability and safety of the reaction conditions. This system usually includes a temperature sensor and a pressure sensor. The temperature sensor is a thermocouple or an RTD sensor, and the pressure sensor is a pressure transmitter. The temperature sensor and the pressure sensor real-time feedback the temperature and pressure data inside the reactor, and through a temperature control instrument, that is, a PID controller, automatically adjust the heating or cooling equipment to maintain the set temperature range. The pressure control system automatically adjusts the gas flow rate and the composition of the reaction gas through a pressure regulating valve and a gas delivery system to ensure that the internal pressure of the reactor is stably within a predetermined range. The entire system is integrated by a PLC controller, automatically adjusting each link to ensure the ideal conditions of the reaction process. At the same time, in case of an abnormality, a warning is given through an alarm system and safety measures are taken. An ultraviolet light source with adjustable wavelength and a gas delivery system are used. Store hexafluoropropylene in a gas storage tank and connect it to the feed port of the vacuum tube reactor I. Set the flow rate of hexafluoropropylene to 12 g / min. The oxygen storage tank is also connected to the feed port of the vacuum tube reactor I, and the flow rate is set to 0.32 g / min. Keep the internal temperature of the vacuum tube reactor I within the range of -30 to -20 °C. Turn on the ultraviolet lamp, and set the wavelength of the incident ultraviolet light to 290 nm. Real-time monitor the pressure and temperature inside the reactor through on-line sensors to ensure the stable operation of the system. Discharge from the discharge port once every 8 minutes, and the discharge is directly transported to storage tank I through a PTFE hose. The volume of storage tank I is 20 L. Regularly sample from the reactor discharge port through an on-line sampling system by a precisely controlled pump or valve. The collected samples are analyzed by a molecular weight distribution analyzer through gel permeation chromatography, gas chromatography, and high performance liquid chromatography to determine the molecular weight distribution and the ratio of mono-terminal and di-terminal acyl fluoride compounds. The analysis results are real-time fed back to the data acquisition system to provide a basis for the control system to automatically adjust the reaction conditions, such as temperature, pressure, gas flow rate, etc., to ensure that the molecular weight range and composition of the intermediate meet the expectations and guarantee the stability of the reaction and the product quality. Detect the perfluoropolyether intermediate in the discharge, that is, the molecular weight distribution of intermediate I is 2200 - 2500 g / mol, among which the mono-terminal acyl fluoride perfluoropolyether compound accounts for 95%, and the di-terminal acyl fluoride compound accounts for about 5%. The chemical equation of the reaction is:

[0066]

[0067] Step 2: Introduce allylamine for addition reaction: Based on the molecular weight of 1350 g / mol of the perfluoropolyether acyl fluoride prepared in Step 1, 335 g (0.1 mol) of Intermediate I is directly transported from Storage Tank I to Reactor II. Dissolve 6.85 g of allylamine in 20 g of 7200 solution, and then add it dropwise to Reactor II by a metering pump within 10 minutes for imidization reaction. Control the reaction temperature at about 0 °C and stir the reaction for 30 min. After the reaction, Intermediate II is obtained. The chemical equation of the reaction is:

[0068]

[0069] Step 3: Synchronously remove peroxide and introduce diallylamine: Transport Intermediate II in Reactor II to Reactor III through a PTFE hose. Reactor III is also a vacuum tube reactor. Keep the temperature in Reactor III at 0 - 10 °C. Set the wavelength of the ultraviolet lamp to 185 nm. Disperse the photocatalyst titanate (the dosage is 1 mol‰ of Intermediate II) and 0.12 mol of diallylamine in 20 g of 7200 solution. The dosage of titanate is 1 mol‰ of Intermediate II. Add it dropwise to Reactor III by a metering pump within 10 min. Under the irradiation of ultraviolet light, the double bond of Intermediate II is activated and can undergo a high-efficiency addition reaction with diallylamine; at the same time, under the catalytic action of titanate, the perfluoropolyether chain segment completes peroxide removal. The perfluoropolyether end product can be obtained in this step. The chemical equation of the reaction is:

[0070]

[0071] Step 4: React with trimethoxyhydroxysilane

[0072] After the addition reaction of diallylamine in Step 3 is completed, turn off the ultraviolet lamp, raise the system temperature to room temperature, and add 0.24 mol of trimethoxyhydroxysilane and the catalyst RuCl2(NHC)(PPh3) (the dosage is 2 mol‰ of Intermediate II) to the reactor by a metering pump to modify the end groups of the perfluoropolyether end product. Continue to stir the reaction for 30 min to obtain the perfluoropolyether anti-fingerprint agent SY1-6 containing 6 methoxy groups and a small amount of DY1-6, thereby introducing the anti-fingerprint coating into the perfluoropolyether end product. The chemical equation of the reaction is:

[0073]

[0074] Step 5: Filter, remove low-boiling reactants and solvents by rotary evaporation, and then separate SY1-6 and DY1-6 by molecular distillation.

[0075] Step 6: Test: spray 4‰ of SY4-6 and DY4-6 7200 solution onto the glass surface, and perform hydrophobic and wear resistance tests on the formed coating. The contact angle data is shown in Figure 4 .

[0076] Without limitation to this, any changes or substitutions that are not conceived through creative work should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope defined in the claims.

Claims

1. A method for synthesizing a perfluoropolyether multifunctional end-group modified material based on the oxidation of hexafluoropropylene by a one-step method, characterized in that It includes the following steps: Step 1: First, hexafluoropropene is converted into a perfluoropolyether intermediate with an acyl fluoride end group, namely intermediate I, through photooxidation; Step 2: Introduce an enamine co-reactant for a tandem reaction: By controlling the reaction conditions, directly introduce an enamine co-reactant to carry out an imidization reaction with the acyl fluoride end group of the acyl fluoride intermediate in Step 1 to form a perfluoropolyether intermediate for further functional group modification, namely intermediate II; Step 3: Simultaneously break the peroxy bond and introduce a dieneamine: Use a photocatalyst at an appropriate temperature to induce the breakage of the peroxy bond in the system to generate a free radical reaction, and at the same time introduce a dieneamine, so that the amino group of the dieneamine undergoes an addition reaction with the unsaturated bond in the perfluoropolyether intermediate under light irradiation, and at the same time complete the deperoxidation of the perfluoropolyether under the catalysis of the photocatalyst to obtain the perfluoropolyether end product; Step 4: Multifunctional modification of the end group: Through end group modification, introduce an anti-fingerprint coating into the perfluoropolyether end product in one step, and then carry out purification and functional testing.

2. The method for synthesizing a perfluoropolyether multifunctional end-group modified material based on hexafluoropropylene oxidation by a one-step method according to claim 1, characterized in that In the photooxidation method described in Step 1, the molar ratio of hexafluoropropene to oxygen is between 1:1 and 1:10, the reaction temperature is -60 to 10 °C, hexafluoropropene and oxygen are oxidized under ultraviolet light irradiation to generate an acyl fluoride intermediate, and the wavelength of the ultraviolet light is 230 to 270 nm.

3. The method for synthesizing a perfluoropolyether multifunctional end-group modified material based on hexafluoropropylene oxidation by a one-step method according to claim 1, characterized in that The conditions for the tandem reaction in Step 2 are a reaction temperature of -20 to 25 °C, a reaction time of 10 to 60 min, the enamine co-reactant is an enamine-based co-reactant, and the enamine-based co-reactant is allylamine.

4. The method for synthesizing a perfluoropolyether multifunctional end-group modified material based on hexafluoropropylene oxidation by a one-step method according to claim 1, characterized in that In Step 3, the dieneamine is diallylamine, the photocatalyst is a titanate or a visible photosensitizer, and the concentration of the photocatalyst is 0.1 to 3 mol%.

5. The method for synthesizing a perfluoropolyether multifunctional end-group modified material based on hexafluoropropylene oxidation by a one-step method according to claim 1, characterized in that In Step 3, ultraviolet light irradiation is carried out using an ultraviolet lamp.

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