Three-step process method for completely dissolving LAP in fluorosilicone acrylate monomer by using PEG-DA phase transfer bridge and application of three-step process method

Abstract

The invention belongs to the technical field of photo-curing materials and photo-initiation systems, and particularly relates to a three-step process method for completely dissolving LAP in a fluorosilicone acrylate monomer by using a PEG-DA phase transfer bridge and application of the three-step process method. On the premise of not changing the main body formula of the target fluorosilicone monomer, the LAP enters the system in a homogeneous and stable form; residues of polar cosolvents such as DMSO (dimethylsulfoxide) are reduced or eliminated, and the optical and toxicological properties of the material are ensured; and a reproducible standardized operation window suitable for amplification is provided. The method is simple in step, mild and capable of being amplified, the obtained resin is clear, stable and good in curing response, and the method is suitable for application scenes with strict requirements for low yellowing and low residue in an optical / medical photocuring material system.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photocuring materials and photoinitiating systems, and particularly relates to a three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers by using a PEG-DA phase transfer bridge and application thereof. BACKGROUND

[0002] LAP is a blue light curing photoinitiator, which can rapidly initiate the curing of photosensitive hydrogel materials under the action of blue light. The application field of LAP is quite wide, especially in biological 3D printing containing cells, since the damage of blue light to cells is smaller, LAP becomes a more ideal choice.

[0003] LAP (Lithium phenyl-2, 4, 6-trimethylbenzoylphosphinate) is easily soluble in hydrogel systems (PBS, HAMA / GelMA, etc.), but it is seriously incompatible with hydrophobic monomers (especially fluorine-containing and silicon-containing acrylates), resulting in turbidity and phase separation when directly added, and it is difficult to obtain a clear homogeneous resin; the oil-soluble azo / phosphine oxide photoinitiator is commonly used in fluorosilicone systems in the existing literature, but the hydrophilicity of LAP determines that it is difficult to be directly replaced; if a mild and low-residue process can be used to realize the homogeneous dispersion of LAP in fluorosilicone monomers, the advantages of LAP in the 405 nm waveband activity, low yellowing and good toxicological properties will be combined, which will provide a new choice for the medical / optical field.

[0004] Based on this, a three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers by using a PEG-DA phase transfer bridge and application thereof are proposed, hoping to solve the problems in the prior art. SUMMARY

[0005] The purpose of the present application is to provide a three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers by using a PEG-DA phase transfer bridge and application thereof, which solves the problems in the prior art.

[0006] The present application is realized by the following technical solutions: A three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers by using a PEG-DA phase transfer bridge, comprising the following steps: S1, adding a LAP-PEG-DA pre-complex into anhydrous DMSO (dimethyl sulfoxide), and after ultrasonic assisted dissolution, filtering with a 0.22 µm PTFE to obtain a LAP mother liquor; S2, mixing the above-mentioned LAP mother liquor and PEG-DA 400 polyethylene glycol (400) diacrylate according to a mass ratio of (0.8~1.5):1, and magnetically stirring at 25°C for 30 min to obtain a "polar bridge" pre-solvent; S3, preheat the fluorosilicone acrylate monomer to 30-40℃, then add the pre-solution prepared in step S2 dropwise into the preheated fluorosilicone acrylate monomer, and stir at 600 rpm to obtain a clear homogeneous phase system; S4, add modified mesoporous SiO2 to the clear homogeneous phase system of S3, stir to disperse uniformly, then transfer to a rotary evaporator for rotary evaporation, after rotary evaporation, filter with a 0.22 μm PTEE filter membrane to remove the modified mesoporous SiO2, perform 405 nm wavelength curing, and finally place on a 180℃ hot table for baking for 1 h.

[0007] Further, the preparation method of the LAP-PEG-DA pre-complex in step S1 is as follows: add LAP and low molecular weight PEG-DA (Mn=200) in a mass ratio of 1:(0.3-0.5) into a reaction bottle, and perform ultrasonic treatment at 30-35℃ and 300 W power until the system is clear and particle-free to form a LAP-PEG-DA pre-complex.

[0008] Further, the ultrasonic dissolution in step S1 is performed at a power of 500 W, a temperature of 50-55℃, and for a time of 10-15 min. The concentration of the LAP mother liquor is 10-40 wt%.

[0009] Further, the fluorosilicone acrylate monomer in step S3 is composed of TFMA 2,2,2-trifluoroethyl methacrylate and TMSPMA 3-(trimethoxysilyl)propyl methacrylate in a mass ratio of (60-80):(20-40). The pre-solution is added at a speed of 1.0 μl to 1500 μl / s.

[0010] Further, the amount of modified mesoporous SiO2 added in step S4 accounts for 0.5-1% of the total mass of the system. The preparation of the modified mesoporous SiO2 includes the following steps: (1) Add deionized water to an electrolytic cell, and sequentially add a biosurfactant and a sodium silicate solution, stir to form a transparent micellar solution, adjust the pH of the system to neutral, and then add KH-550 and stir for 10-20 min; (2) Insert a titanium-based reticular anode and a stainless steel cathode, pass direct current, react in a constant temperature water bath at 60-65℃ for 2-3 h, then transfer to a sealed container, and form a stable gel by static aging at 40℃ for 12-14 h, separate the solid product by vacuum filtration, and wash with deionized water until the filtrate is neutral; (3) The above washed wet gel is mixed with anhydrous ethanol according to a mass ratio of 1: (5-6), and is placed in a high-pressure reaction kettle, and is treated at 120 DEG C and 8 MPa for 2-3 h, and is vacuum dried at 60-65 DEG C for 6-7 h.

[0011] Further, the biosurfactant in step (1) is Tween 80, the concentration is 0.05 mol / L, the concentration of sodium silicate solution is 0.5 mol / L, and the molar ratio of KH-550 to sodium silicate is 1:20.

[0012] Further, the distance between the titanium-based reticular anode and the stainless steel cathode in step (2) is 5-6 cm, and the current density of the direct current is 5 mA / cm 2 .

[0013] Further, the rotary evaporation condition in step S4 is that the temperature is 35-40 DEG C, the vacuum degree is less than or equal to 50 mbar, and the rotary evaporation time is 10-20 min.

[0014] Further, the DMSO is removed by rotary evaporation in step S4, and the DMSO residue in the system after desolvation is less than 0.1 wt%, which is confirmed by 1 H-NMR.

[0015] Further, the 405 nm wavelength curing condition in step S4 is that the 20 mW / cm 2 is irradiated for 10 s to be tacky.

[0016] A three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers by PEG-DA phase transfer bridge is applied in ultraviolet / visible light curing materials.

[0017] Compared with the prior art, the present application has the following advantages: 1. The present application realizes long-term homogeneous stability of LAP in a fluorosilicone system without changing the main formula of the target fluorosilicone monomer, solves the problems of short-term clarification and long-term failure in a traditional incompatible system, provides a stable raw material basis for subsequent material processing, avoids product yield fluctuation caused by unstable system, and provides a reproducible, scalable standardized operation window.

[0018] 2. The method of the present application obtains a clear and stable homogeneous system (no turbidity / crystallization after placing at 25 DEG C for more than 7 days); the DMSO residue is less than 0.1 wt% after 1 H-NMR confirmation, and the optical transmittance and curing performance are not adversely affected.

[0019] 3、The method of the application has simple and mild steps and can be scaled up. The obtained resin is clear, stable and has good curing response, and is suitable for low-yellowing and low-residual applications in optical / medical light-curing material systems. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 H-NMR spectra of the system after DMSO removal 1 H-NMR spectra of the system after DMSO removal Figure 2 H-NMR spectra of the system before (containing DMSO) and after DMSO removal 1 H-NMR spectra of the system before (containing DMSO) and after DMSO removal Figure 3 Process flow chart of Example 1 in the specific embodiment of the application. DETAILED DESCRIPTION

[0021] In order to further explain the application, the following specific examples are described.

[0022] Example 1

[0023] A three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers by PEG-DA phase transfer bridge, comprising the following steps: S1, 2 g of LAP was added to 8 g of DMSO, and ultrasonic treatment was performed at 50°C for 10 min until it was clear. A 20 wt% LAP mother liquor was obtained by filtration with a 0.22 µm PTFE filter; S2, the above-mentioned LAP mother liquor was mixed with PEG-DA at a mass ratio of 1:1, and magnetic stirring was performed at 25°C for 30 min to obtain a "polar bridge" pre-solvent; S3, the fluorosilicone acrylate monomer was preheated to 35°C, then 2 g of the pre-solvent prepared in step S2 was added dropwise into 18 g of the preheated fluorosilicone acrylate monomer (TFMA 75 wt% / TMSPMA 25 wt%), and stirring was performed at 35°C and 600 rpm for 10 min to obtain a clear homogeneous system; S4, 35°C, ≤ 50 mbar, rotary evaporation for 15 min to remove DMSO, nitrogen for 5 min, 405 nm, 20 mW / cm 2 photocuring for 10 s.

[0024] DMSO residue: the obtained system is transparent; 1H-NMR (400 MHz, CDCl3) no DMSO residual peak at 2.50 ppm (noise), methyl methacrylate at 1.95 ppm, olefin H at 5.60 / 6.10 ppm, PEGDA-CH2-O at 3.65 ppm, TMSPMA-OCH3 at 3.60 ppm, weak aromatic region (LAP) at 6.9-7.2 ppm; Stability: no turbidity at 25℃ for 7 days; Curing: 405 nm, 20 mW / cm 2 Cured with 10 s light exposure, no softening at 180℃ baking; Viscosity: 250 mPa·s at 25℃; Transmittance: 91% in 400-800 nm wavelength.

[0025] Example 2

[0026] A three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers with PEG-DA phase transfer bridge, including the following steps: S1, add LAP and low molecular weight PEG-DA (Mn=200) according to a mass ratio of 1:0.4 into a reaction bottle, 30-35℃, 300 W power ultrasonic treatment until the system is clear and no particles, forming LAP-PEG-DA pre-complex; S2, add the LAP-PEG-DA pre-complex into anhydrous DMSO (dimethyl sulfoxide), after 10 min ultrasonic treatment at 50℃, filter with 0.22 µm PTFE to obtain 20 wt% LAP mother liquor; S3, mix the above LAP mother liquor with PEG-DA according to a mass ratio of 1:1, magnetically stir at 25℃ for 30 min to obtain “polar bridge” pre-solvent; S4, preheat the fluorosilicone acrylate monomers to 35℃, then add 2 g of the pre-solvent prepared in step S2 into 18 g of the preheated fluorosilicone acrylate monomers (TFMA 75 wt% / TMSPMA 25 wt%), stir at 600 rpm for 10 min at 35℃ to obtain a clear homogeneous system; S5, 35℃, ≤ 50 mbar rotary evaporation for 15 min to remove DMSO, after 5 min nitrogen purging, 405 nm, 20 mW / cm 2 Cured with 10 s light exposure.

[0027] Stability: no turbidity at 25℃ for 10 days; DMSO residual, curing performance, viscosity, and transmittance are consistent with Example 1.

[0028] Example 3

[0029] A three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers with PEG-DA phase transfer bridge, comprising the following steps: S1, 2 g LAP was added to 8 g DMSO, ultrasonic at 50℃ for 10 min to clear, 0.22 µm PTFE filtration to get 20 wt% LAP stock solution; S2, the above LAP stock solution was mixed with PEG-DA according to the mass ratio of 1:1, magnetic stirring at 25℃ for 30 min to get "polar bridge" pre-solvent; S3, the fluorosilicone acrylate monomer was preheated to 35℃, then 2 g of the pre-solvent prepared in step S2 was added dropwise into 18 g of preheated fluorosilicone acrylate monomer (TFMA 75 wt% / TMSPMA 25 wt%), stirred at 35℃ for 10 min at 600 rpm to get a clear homogeneous system; S4, modified mesoporous SiO2 was added to the clear homogeneous system of S3, stirred to disperse uniformly, then transferred to a rotary evaporator for rotary evaporation, after rotary evaporation, filtered with a 0.22 μm PTEE filter membrane to remove the modified mesoporous SiO2, cured at 405 nm wavelength, and finally placed on a 180℃ hot table for baking for 1 h; The amount of modified mesoporous SiO2 added accounts for 0.7% of the total mass of the system; The preparation of the modified mesoporous SiO2 comprises the following steps: (1) Deionized water was added to the electrolytic cell, followed by the addition of biobased surfactant Tween 80 (concentration of 0.05 mol / L) and sodium silicate solution (concentration of 0.5 mol / L), stirred to form a transparent micellar solution, adjusted the pH of the system to neutral, then added KH-550, the molar ratio of KH-550 to sodium silicate was 1:20, stirred for 15 min; (2) Insert the titanium-based mesh anode and stainless steel cathode, the distance between the titanium-based mesh anode and the stainless steel cathode is 5.5 cm, pass direct current, the current density of the direct current is 5 mA / cm 2 , react in a 62℃ constant temperature water bath for 2.5 h, then transfer to a sealed container, static aging at 40℃ for 13 h to form a stable gel, separate the solid phase product by vacuum filtration, wash with deionized water until the filtrate is neutral; (3) Mix the above washed wet gel with anhydrous ethanol according to the mass ratio of 1:5.5, place it in a high-pressure reaction kettle, treat it at 120℃ and 8 MPa for 2.5 h, then vacuum dry at 62℃ for 6.5 h.

[0030] DMSO residue: the GC-MS detection signal intensity is lower than that of Example 1, the DMSO residue is further reduced; Stability, curing performance, and light transmittance are consistent with Example 1.

[0031] Example 4

[0032] A three-step process method for completely dissolving LAP in fluorosilicone acrylate monomers with PEG-DA phase transfer bridge, including the following steps: S1, add LAP and low molecular weight PEG-DA (Mn=200) according to a mass ratio of 1:0.4 into a reaction bottle, ultrasonic treatment at 32℃ and 300W power until the system is clear and free of particles, forming a LAP-PEG-DA pre-complex; S2, add the LAP-PEG-DA pre-complex into anhydrous DMSO (dimethyl sulfoxide), ultrasonic treatment at 50℃ for 10 min, then filter with a 0.22 µm PTFE filter to obtain a 20 wt% LAP mother liquor; S3, mix the above LAP mother liquor with PEG-DA according to a mass ratio of 1:1, magnetic stirring at 25℃ for 30 min to obtain a "polar bridge" pre-solvent; S4, preheat the fluorosilicone acrylate monomer to 35℃, then add 2 g of the pre-solvent prepared in step S2 into 18 g of the preheated fluorosilicone acrylate monomer (TFMA 75 wt% / TMSPMA 25 wt%), stir at 600 rpm for 10 min at 35℃ to obtain a clear homogeneous system; S5, add modified mesoporous SiO2 to the clear homogeneous system of S3, stir to disperse uniformly, then transfer to a rotary evaporator for rotary evaporation, after rotary evaporation, filter with a 0.22 μm PTEE filter to remove the modified mesoporous SiO2, perform 405 nm wavelength curing, and finally place on a 180℃ hot table for baking for 1 h; The amount of the modified mesoporous SiO2 added is 0.7% of the total mass of the system; The preparation of the modified mesoporous SiO2 includes the following steps: (1) Add deionized water to the electrolytic cell, then add biobased surfactant Tween 80 (concentration of 0.05 mol / L) and sodium silicate solution (concentration of 0.5 mol / L) in sequence, stir until a transparent micellar solution is formed, adjust the pH of the system to neutral, then add KH-550, the molar ratio of KH-550 to sodium silicate is 1:20, stir for 15 min; (2) Insert a titanium-based reticular anode and a stainless steel cathode, the distance between the titanium-based reticular anode and the stainless steel cathode is 5.5 cm, pass direct current, the current density of the direct current is 5 mA / cm 2 , react in a 62℃ constant temperature water bath for 2.5 h, then transfer to a sealed container, static aging at 40℃ for 13 h to form a stable gel, separate the solid phase product by vacuum filtration, and wash with deionized water until the filtrate is neutral; (3) The washed wet gel was mixed with anhydrous ethanol at a mass ratio of 1:5.5, and placed in a high-pressure reactor. After being treated at 120°C and 8 MPa for 2.5 h, it was vacuum dried at 62°C for 6.5 h.

[0033] Stability: No turbidity after standing at 25°C for 10 days; DMSO residue: The signal intensity detected by GC-MS was lower than that of Example 1, and the DMSO residue was further reduced; Viscosity: 230 mPa·s (slightly lower than Example 1); Curing performance, viscosity, and light transmittance were consistent with Example 1.

[0034] Example 5 (Increase the proportion of "polar bridge") Pre-sol preparation: LAP mother liquor: PEGDA400 = 1:1.5 (mass ratio), the rest is the same as Example 1.

[0035] Viscosity: 320 mPa·s at 25°C (Example 1 is 250 mPa·s); Stability, DMSO residue, curing performance, and light transmittance were consistent with Example 1.

[0036] Example 6 (Increase the effective concentration of LAP) Pre-sol target LAP effective concentration 15 wt%: Prepare LAP mother liquor (30 wt%), then prepare pre-sol with PEGDA400 = 1:1.

[0037] A clear system can still be obtained after dropping into the monomer; it is recommended to extend the rotary evaporation time from 15 min to 20 min to ensure sufficient desolventization.

[0038] Tensile strength after curing: 12% higher than Example 1; Stability, DMSO residue, and light transmittance were consistent with Example 1.

[0039] Example 7 (Adjust the composition of fluorosilicon monomer) Monomer combination: TFMA: TMSPMA = 60:40 (mass ratio), the rest is the same as Example 1; The characteristic peak position of methacrylic acid in NMR spectrum did not change, and the integral ratio changed slightly with the difference in formula; Stability, DMSO residue, and light transmittance were consistent with Example 1.

[0040] Example 8 (Change of PEGDA molecular weight) Replace PEGDA400 with PEGDA700 (Mn≈700), the rest is the same as Example 1; Viscosity: 380 mPa·s at 25°C; The stability, DMSO residue, curing performance, and light transmittance were the same as those of Example 1.

[0041] The above detailed description of the specific embodiments of the present application has further explained the purposes, technical solutions, and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A three-step process method for complete dissolution of LAP in fluorosilicone acrylate monomers with PEG-DA phase transfer bridge characterized by, Comprising the following steps: S1, adding LAP-PEG-DA pre-complex into anhydrous DMSO, dissolving under ultrasonic assistance, and then filtering with PTFE to obtain a LAP mother liquor; S2, mixing the LAP mother liquor with PEG-DA 400 under magnetic stirring to obtain a "polar bridge" pre-solvent; S3, adding the pre-solvent prepared in step S2 into preheated fluorosilicon acrylate monomers under stirring at 600 rpm to obtain a clear homogeneous phase system; S4, adding modified mesoporous SiO2 into the clear homogeneous phase system of S3 under stirring to uniformly disperse the modified mesoporous SiO2, then transferring the system to a rotary evaporator for rotary evaporation, filtering with PTFE after rotary evaporation, and finally curing at a wavelength of 405 nm and baking on a hot table.

2. The three-step process method of complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge according to claim 1, wherein, The preparation method of the LAP-PEG-DA pre-complex in step S1 is as follows: adding LAP and low molecular weight PEG-DA into a reaction bottle according to a mass ratio of 1:(0.3-0.5), and treating the system under ultrasonic assistance at 30-35℃ and a power of 300 W until the system is clear and free of particles to form a LAP-PEG-DA pre-complex.

3. The three-step process method of complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge according to claim 1, wherein, The power for ultrasonic assistance in step S1 is 500 W, the temperature is 50-55℃, and the time is 10-15 min. The concentration of the LAP mother liquor is 10-40 wt%.

4. The three-step process method of complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge according to claim 1, wherein, The mass ratio of the LAP mother liquor to PEG-DA 400 in step S2 is (0.8-1.5):

1. The magnetic stirring conditions are as follows: magnetic stirring at 25℃ for 30 min.

5. The three-step process of claim 1 for complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge, wherein, The fluorosilicon acrylate monomers in step S3 are composed of TFMA and TMSPMA, and the mass ratio is (60-80):(20-40). The pre-solvent is added at a speed of 1.0 µml-1500 µml / s. The temperature during preheating is controlled at 30-40℃.

6. The three-step process of claim 1 for complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge, wherein, The amount of the modified mesoporous SiO2 added in step S4 accounts for 0.5-1% of the total mass of the system. The preparation of the modified mesoporous SiO2 comprises the following steps: (1) adding deionized water into an electrolytic cell, sequentially adding a biosurfactant and a sodium silicate solution, stirring until a transparent micellar solution is formed, adjusting the pH of the system to neutral, and then adding KH-550 and stirring for 10-20 min; (2) inserting a titanium-based reticular anode and a stainless steel cathode, passing direct current, and reacting in a constant-temperature water bath at 60-65℃ for 2-3 h, then transferring to a sealed container for static aging at 40℃ for 12-14 h to form a stable gel, and separating the solid product by vacuum filtration and washing with deionized water until the filtrate is neutral; (3) mixing the washed wet gel with anhydrous ethanol according to a mass ratio of 1:(5-6), placing in a high-pressure reaction kettle, treating at 120℃ and 8 MPa for 2-3 h, and then vacuum drying at 60-65℃ for 6-7 h.

7. The three-step process method of complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge according to claim 6, wherein, The biosurfactant in step (1) is Tween 80 with a concentration of 0.05 mol / L, the concentration of the sodium silicate solution is 0.5 mol / L, and the molar ratio of KH-550 to sodium silicate is 1:

20.

8. The three-step process of claim 6 for complete dissolution of LAP in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge, characterized in that, The distance between the titanium-based reticular anode and the stainless steel cathode in step (2) is 5-6 cm, and the current density of the direct current is 5 mA / cm 2 .

9. The three-step process of dissolving LAP completely in fluorosilicone acrylate monomers using PEG-DA phase transfer bridge according to claim 1, characterized in that, The rotary evaporation in step S4 is carried out at a temperature of 35-40℃, a vacuum degree of ≤50 mbar, and a rotary evaporation time of 10-20 min. The 405 nm wavelength curing conditions were: 20 mW / cm 2 Dry to touch in 10 s; The hot plate baking temperature is 180℃, and the time is 1 h.

10. Use of the process according to any one of claims 1 to 9 for the UV / vis light curing of materials.

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