Method for realizing'active ' / controllable free radical polymerization of hydrophilic and / or hydrophobic monomer under air condition

Abstract

The invention discloses a method for realizing'active ' / controllable free radical polymerization of hydrophilic and / or hydrophobic monomers under an air condition, relates to the field of'active' / controllable free radical polymerization, and aims to solve the problem of narrow monomer selection range in the prior art. A functional monomer comprising a hydrophobic monomer, a halide, copper bromide, a ligand and a nonionic surfactant-GOx are subjected to monomer polymerization in a solvent through an initiator azodiisobutylimidazoline hydrochloride (VA-044), and a polymer with narrow target molecular weight and molecular weight distribution is formed. According to the method, the glucose oxidase modified by the nonionic surfactant is introduced into the'active ' / controllable free radical polymerization reaction, and an effective way for quickly and efficiently synthesizing a target polymer from a hydrophobic monomer under the mild air condition is provided.

Description

Technical Field

[0001] The present invention belongs to the technical field of "living" / controlled free radical polymerization, and specifically is a method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions. Background Art

[0002] Glucose oxidase (GOx), GOx consumes O2, oxidizes glucose into D-glucono-δ-lactone, and produces hydrogen peroxide at the same time. This process can be used to achieve deoxygenation of "active" / controlled free radical polymerization. However, in GOx-assisted "active" / controlled free radical polymerization, the applicable monomer range is limited, and it is only applicable to water-soluble monomers. Therefore, it is urgent to expand the monomer range. Summary of the invention

[0003] The technical problem solved by the present invention is to overcome the existing defects and provide a "live" / controlled radical polymerization method that can realize a wide range of monomer selection including hydrophobic monomers under air conditions. The non-ionic surfactant-GOx is used to deoxygenate the "live" / controlled radical polymerization, thereby performing atom transfer radical polymerization (ATRP) of the hydrophobic monomer. In addition to realizing the polymerization of the hydrophobic monomer, the conversion rate of the hydrophobic monomer can also be improved, which greatly broadens the applicable scope of the monomer and finds a new polymerization method for the "live" / controlled radical polymerization reaction of the hydrophobic monomer.

[0004] The technical problem to be solved by the present invention is to overcome the existing defects and provide a method for realizing "active" / controllable free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions, which can effectively solve the problems in the background technology.

[0005] In order to achieve the above-mentioned object, the present invention discloses a method for realizing "living" / controllable free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions, and the technical scheme adopted is comprising the following steps:

[0006] Step 1, dissolving a functional monomer, an initiator, a metal halide, a ligand and glucose oxidase modified with a non-ionic surfactant in a solvent; the functional monomer is at least one of a water-soluble monomer and a hydrophobic monomer;

[0007] Step 2: Continue stirring for 12-24 hours under closed conditions at 45°C to carry out polymerization reaction. The reaction equation is as follows:

[0008]

[0009] As a preferred technical solution of the present invention, the functional monomers include acrylic acid, methyl acrylate (MA), ethyl acrylate (EA), tert-butyl acrylate (tBA), n-butyl acrylate (nBA), glycidyl methacrylate, methyl methacrylate (MMA), polyethylene glycol monomethyl ether methacrylate (OEOMA), 500 ). The structural formula of some monomers is as follows:

[0010] A) Hydrophobic Monomer

[0011]

[0012] B) Water-soluble monomer

[0013]

[0014] As a preferred technical solution of the present invention, the ligand is one or more of tris[2-(dimethylamino)ethyl]amine (Me6TREN), tris(2-pyridylmethyl)amine (TPMA), 2,2'-bipyridine (bpy), N,N,N'N'-tetramethylethylenediamine (PMDTEA). Among them, Me6TREN and TPMA are highly active ligands, bpy and PMDTEA are low-activity ligands, and their structural formulas are as follows:

[0015]

[0016] As a preferred technical solution of the present invention, the preparation method of the glucose oxidase modified with a nonionic surfactant is as follows:

[0017] First, a higher alcohol is reacted with L-glutamic acid to obtain an intermediate product, and then the intermediate product is reacted with glucose to obtain glucosyl-1-glutamic acid dioleate and its derivatives, and then the derivative (S) of glucosyl-1-glutamic acid dioleate is used to modify glucose oxidase (GOx) to obtain the target product glucose oxidase modified with a nonionic surfactant (S-GOx), and the reaction equation is:

[0018]

[0019] Wherein, the higher alcohol is n-decanol, tetradecanol or octadecanol. S-GOx can not only deoxygenate the hydrophobic monomer, but also control the hydrophobic monomer to react with copper bromide, ligand and initiator within a certain range, thereby realizing precise control of the polymerization reaction conditions, and can achieve fine regulation of the polymer molecular weight, molecular weight distribution, microstructure and macroscopic properties, which can not only meet the strict requirements of material performance in specific applications, but also improve the consistency and reliability of the product.

[0020] As a preferred technical solution of the present invention, the initiator includes a first initiator and a second initiator, the first initiator is one or more of ethyl 2-bromoisobutyrate and its halides; the second initiator is azobisisobutylimidazoline hydrochloride (VA-044).

[0021] As a preferred technical solution of the present invention, the molar ratio of the functional monomer, the metal halide, the first initiator, the ligand, the glucose oxidase modified with a nonionic surfactant and the second initiator is x / 1 / 0.6 / 2.4 / 2.0 / 6.0, wherein the value of x is 50-600, which is determined by the degree of polymerization, that is, the ratio of the monomer and the first initiator.

[0022] As a preferred technical solution of the present invention, the metal halide is copper bromide.

[0023] As a preferred technical solution of the present invention, in step 2, the mixture is stirred steadily at 45° C. for 12-24 hours.

[0024] The present invention also discloses the application of the above method capable of realizing "living" / controllable free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions in the preparation of water-based coatings and adhesives.

[0025] Compared with the prior art, the invention has the following beneficial effects: the invention modifies glucose oxidase by using a surfactant so that it can deoxygenate the hydrophobic monomer, thereby increasing the stability and solubility in anhydrous medium and broadening the selection range of the monomer. The glucose oxidase used in the polymerization method disclosed by the invention is low-priced, environmentally friendly, and can consume oxygen in the system; the reaction conditions of the method are mild and easy to achieve, the reaction operation is simple, and no cumbersome deoxygenation operation is required. The polymerization reaction is fast and efficient, and the polymerization of the hydrophobic monomer can be achieved, and the conversion rate can reach more than 99% within 12 hours; the target molecular weight of the product is controllable, and the polydispersity is narrow. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the hydrogen nuclear magnetic resonance spectrum of the ligand TPMA of the present invention;

[0027] Figure 2 is the hydrogen nuclear magnetic resonance spectrum of glucosyl-1-glutamic acid dioleate of the present invention;

[0028] Figure 3 is the hydrogen nuclear magnetic resonance spectrum of the glucosyl-1-glutamic acid dioleate derivative of the present invention;

[0029] Figure 4 This is a comparison chart of the activities of S-GOx obtained using different higher alcohols in the present invention;

[0030] Figure 5This is the GPC spectrum of the polymethyl acrylate with the target degree of polymerization synthesized in Example 1 of the present invention;

[0031] Figure 6 This is the hydrogen nuclear magnetic resonance spectrum of the product of the ATRP reaction of the hydrophobic monomer methyl acrylate in air and the chain extension;

[0032] Figure 7 The GPC spectrum of the polymethyl acrylate with the target polymerization degree synthesized by the present invention and its self-extended chain product. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Example 1

[0035] This embodiment discloses a first implementation mode of the present invention, and the adopted technical solution is to include the following steps:

[0036] Step 1, synthesize the ligand TPMA,

[0037] 2-(Chloromethyl)pyridine hydrochloride (30.6mmol, 5.02g), anhydrous sodium carbonate (300.2mmol, 31.83g), anhydrous acetonitrile (100mL) were added to a 250mL round-bottom flask and covered with a rubber stopper. Then, 2-(aminomethyl)pyridine (15mmol, 1.63g) was dissolved in 50mL of anhydrous acetonitrile and added dropwise to the reaction flask under Ar2 atmosphere. The reaction mixture was stirred steadily for 30min under Ar2 atmosphere and refluxed at 90°C and Ar2 atmosphere for 12h. After the reaction was completed, the white precipitate was removed by suction filtration, and the acetonitrile was then removed by rotary evaporation. The obtained solid was repeatedly extracted three times with 60mL of dichloromethane to obtain an organic phase. After removing the dichloromethane, the organic phase was recrystallized in hot acetone to obtain a yellow solid, which was then used as the solvent. 1 The structure was characterized by H NMR. Figure 1 As shown (the ordinate is intensity);

[0038] Step 2, preparing the nonionic surfactant glucosyl-1-glutamic acid dioleate,

[0039] A mixture of L-glutamic acid, n-decanol and p-toluenesulfonic acid (molar ratio is 1:2:1) is refluxed in a toluene solution at 120°C for 4 hours. Then, it is cooled to room temperature, toluene is removed under reduced pressure, and the reaction mixture is neutralized with a 10% sodium bicarbonate solution. The aqueous phase is then extracted with ethyl acetate. If emulsification is severe during the reaction, the organic phase is extracted with a 10% sodium bicarbonate and saturated sodium chloride solution. After the extraction is completed, a large amount of anhydrous magnesium sulfate is added for drying, and the white solid is removed by filtration with a Buchner funnel, and the mixture is concentrated under reduced pressure. Then, silica gel column chromatography is performed for purification. First, the raw material n-decanol is filtered out with DCM, and then the column is flushed twice with DCM:MeOH=60:1, and finally the product is filtered out with DCM:MeOH=30:1, and vacuum concentrated to obtain a light yellow liquid, and then the mixture is purified by filtration with a Buchner funnel. 1 The structure was characterized by H NMR. Figure 2 As shown (the vertical axis is signal strength);

[0040] Step 3, preparing a derivative (S) of nonionic surfactant glucosyl-1-glutamic acid dioleate,

[0041] Hydrochloric acid was added to the light yellow liquid obtained in step 2 to form a salt (white viscous solid), which was recrystallized in acetone to obtain a white solid; then, a mixture of the solid salt, gluconolactone and triethylamine (molar ratio of 1:1:1) was refluxed in ethanol for 2 h, the solvent was removed under reduced pressure, and the crude product was recrystallized in acetone to obtain the target compound S. 1 The structure was characterized by H NMR. Figure 3 As shown (the vertical axis is signal strength);

[0042] Step 4, preparing nonionic surfactant glucosyl-1-glutamic acid dioleate derivative-glucose oxidase (S-GOx),

[0043] The white solid (0.15 mmol) obtained in step 3 was dissolved in 30 mL of toluene, and the mixed solution and glucose oxidase (0.5 mmol) were dissolved in 10 mL of PBS buffer solution, and the mixture was shaken in an oscillator at a speed of 1500 rpm for 12 h, and then dialyzed and freeze-dried to obtain a white powder, which is the target S-GOx;

[0044] Step 5, using hydrophobic monomer methyl acrylate to carry out ATRP reaction under air,

[0045] Methyl acrylate (MA, 0.86 g, 10 mmol), ethyl 2-bromoisobutyrate (0.0058 g, 0.03 mmol), copper bromide (0.0046 g, 0.02 mmol), VA-044 (0.064 g, 0.2 mmol), ligand (TPMA, 0.0232 g, 0.08 mmol) and S-GOx (0.084 g, 0.08 mmol) obtained in step 4 were placed in a 5 mL round-bottom flask, PBS buffer solution (0.08 mmol, 2.5 g) was used as solvent, the flask was sealed with a glass stopper, and a sealing film was wrapped to make the whole system in a closed state. The reaction mixture was stirred steadily at 45 ° C for 24 h. After the reaction was completed, a small amount of sample was taken to calculate the monomer conversion rate of 99.2%, and the polymer was used 1 The structure was characterized by HNMR. Figure 6 The first segment is shown in the GPC spectrum of the polymer. Figure 5 As shown (the vertical axis is signal strength).

[0046] Example 2

[0047] The difference between this embodiment and embodiment 1 is that, during the ATRP reaction, the reaction mixture was stirred steadily at 45° C. for 12 h. After the reaction was completed, a small amount of sample was taken to calculate the monomer conversion rate of 80%; then additional PBS buffer solution (0.08 mmol, 2.5 g) and methyl acrylate (0.8609 g, 10 mmol), VA-044 (0.064 g, 0.2 mmol) were added to the reaction mixture for chain extension, and then S-GOx (0.084 g, 0.08 mmol) was added for polymerization reaction. After 12 h, a small amount of sample was taken to calculate the monomer conversion rate of 99.7%. 1 The structure was characterized by H NMR. Figure 6 The second segment is shown in the GPC spectrum of the polymer. Figure 7 As shown (the vertical axis is signal strength).

[0048] Example 3

[0049] The difference between this embodiment and embodiment 1 is that the hydrophobic monomer used in step 5 is EA.

[0050] Example 4

[0051] The difference between this embodiment and embodiment 1 is that the hydrophobic monomer used in step 5 is nBA.

[0052] The ATRP polymerization products of Examples 1, 3, and 4 were compared, and the results were as follows:

[0053]

[0054] From the above comparison, it can be seen that with the growth of the carbon chain of the group, the final conversion rate of ATRP polymerization gradually decreases, but the polydispersity coefficient first increases and then decreases. When nBA is used, although the conversion rate is low, the polydispersity coefficient is close to 1, and the performance is relatively stable. When EA is used, the conversion rate is lower than that of MA monomer, and the polydispersity coefficient is higher. The performance of the polymer is more affected by the difference between molecules.

[0055] Example 5

[0056] The difference between this embodiment and embodiment 1 is that the higher alcohol used in preparing the nonionic surfactant glucosyl-1-glutamic acid dioleate in step 2 is tetradecanol.

[0057] Example 6

[0058] The difference between this embodiment and embodiment 5 is that the hydrophobic monomer used in step 5 is EA.

[0059] Example 7

[0060] The difference between this embodiment and embodiment 5 is that the hydrophobic monomer used in step 5 is nBA.

[0061] The ATRP polymerization products of Examples 5, 6, and 7 were compared, and the results were as follows:

[0062]

[0063] From the above comparison, it can be seen that with the growth of the carbon chain of the group, the final conversion rate of ATRP polymerization decreases, but the polydispersity coefficient first increases and then decreases. When nBA is used, although the conversion rate is low, the polydispersity coefficient approaches 1 and the performance is relatively stable. When EA is used, the polydispersity coefficient is higher and the performance of the polymer is more affected by the difference between molecules.

[0064] Example 8

[0065] The difference between this embodiment and embodiment 1 is that the higher alcohol used in preparing the nonionic surfactant glucosyl-1-glutamic acid dioleate in step 2 is octadecyl alcohol.

[0066] Example 9

[0067] The difference between this embodiment and embodiment 8 is that the hydrophobic monomer used in step 5 is EA.

[0068] Example 10

[0069] The difference between this embodiment and embodiment 8 is that the hydrophobic monomer used in step 5 is nBA.

[0070] The ATRP polymerization products of Examples 8, 9, and 10 were compared, and the results were as follows:

[0071]

[0072] From the above comparison, it can be seen that with the growth of the carbon chain of the group, the final conversion rate of ATRP polymerization decreases, but the polydispersity coefficient first increases and then decreases. When nBA is used, although the conversion rate is low, it is improved compared with n-decanol and tetradecanol. The polydispersity coefficient approaches 1 and the performance is relatively stable. When EA is used, the polydispersity coefficient is higher, and the performance of the polymer is more affected by the difference between molecules.

[0073] The enzyme activity of S-GOx prepared using tetradecanol and octadecanol was Figure 4 shown.

[0074] The VA-044 used in this article is a commercially available product and belongs to the prior art.

[0075] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for achieving "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions, characterized in that: The following steps are involved: Step 1, dissolving a functional monomer, an initiator, a metal halide, a ligand and glucose oxidase modified with a non-ionic surfactant in a solvent; the functional monomer is at least one of a water-soluble monomer and a hydrophobic monomer; Step 2: The polymerization reaction can be carried out by continuous stirring under closed and heated conditions. The reaction equation is as follows:

2. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 1, characterized in that: The functional monomers include acrylic acid, methyl acrylate, ethyl acrylate, tert-butyl acrylate, n-butyl acrylate, glycidyl methacrylate, methyl methacrylate, and polyethylene glycol monomethyl ether methacrylate.

3. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 1, characterized in that: The ligand is one or more of tris[2-(dimethylamino)ethyl]amine, tris(2-pyridylmethyl)amine, 2,2'-bipyridine, and N,N,N'N'-tetramethylethylenediamine.

4. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 1, characterized in that: The preparation method of the glucose oxidase modified with a nonionic surfactant is as follows: First, a higher alcohol is reacted with L-glutamic acid to obtain an intermediate product, and then the intermediate product is reacted with glucose to obtain glucosyl-1-glutamic acid dioleate and its derivatives, and then the derivatives of glucosyl-1-glutamic acid dioleate are used to modify glucose oxidase, and the reaction equation is: Wherein, the higher alcohol is n-decanol, tetradecanol or octadecyl alcohol.

5. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 1, characterized in that: The initiator comprises a first initiator and a second initiator, wherein the first initiator is one or more of ethyl 2-bromoisobutyrate and its halides; The second initiator is azobisisobutylimidazoline hydrochloride.

6. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 5, characterized in that: The molar ratio of the functional monomer, the first initiator, the metal halide, the ligand, the glucose oxidase modified with a nonionic surfactant and the second initiator is x / 1 / 0.6 / 2.4 / 2.0 / 6.0; wherein the value of x is 50-600, which is determined by the degree of polymerization.

7. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 1, characterized in that: The metal halide is copper bromide.

8. The method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions according to claim 1, characterized in that: In the step 2, the mixture is stirred steadily at 45° C. for 12-24 hours.

9. Use of the method for realizing "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions as described in claims 1-8 in the preparation of water-based coatings.

10. Use of the method for achieving "living" / controlled free radical polymerization of hydrophilic and / or hydrophobic monomers under air conditions as described in claims 1-8 in the preparation of an adhesive.

Images