Acrylate solution polymer and preparation method thereof

Abstract

The invention provides an acrylate solution polymer and a preparation method thereof, and belongs to the technical field of polymer preparation. The invention provides a preparation method of an acrylate solution polymer, which comprises the following steps: respectively introducing an acrylate monomer solution and an initiator solution into a tubular reactor to carry out polymerization reaction, and carrying out programmed control on the temperature of the polymerization reaction according to a formula 1, and carrying out programmed control on the introduction rate of the reactant solution according to a formula 2 to obtain the acrylate solution polymer, the reactant solution comprises an acrylate monomer solution and an initiator solution. On the basis of polymerization reaction kinetics and a kinetics mechanism, programmed control is carried out by limiting the temperature of the polymerization reaction and the introduction rate of a reactant solution, so that the acrylate solution polymer with narrow molecular weight distribution is obtained.

Description

Technical Field

[0001] The invention relates to the technical field of polymer preparation, and in particular to an acrylic ester solution polymer and a preparation method thereof. Background Art

[0002] Acrylic polymers have a wide range of applications in multiple fields, mainly including the following aspects: Film formers: Acrylic polymers are often used as film formers for coatings, adhesives and inks due to their excellent transparency, chemical resistance and weather resistance, and can significantly improve the film-forming effect and chemical resistance of these products; Thickeners: Their unique molecular structure enables them to form a three-dimensional network structure, thereby increasing the viscosity of coatings, adhesives, etc., and having a thickening effect. In addition, acrylic copolymers can prevent the stratification, solidification and deterioration of coating components, thereby extending the service life of the coating; Skin care ingredients: In skin care products, acrylic polymers can form a protective film to prevent water loss, enhance moisturizing effects, improve skin texture, and resist damage from the external environment. They can also increase the viscosity and stability of skin care products, making the products easier to apply and absorb.

[0003] The acrylic polymers provided in the related art have the problem of wide molecular weight distribution (PDI), which can lead to uneven physical properties, including decreased mechanical properties and fluctuations in thermal properties; processing performance problems, including difficulty in viscosity control, reduced uniformity, resulting in poor film forming properties or uneven film thickness; inconsistent chemical properties, including difficulty in cross-linking and curing control, poor solubility, reduced chemical resistance, limited application performance, etc., making it difficult to meet high-end application requirements. Summary of the invention

[0004] In view of this, the object of the present invention is to provide an acrylate solution polymer and a preparation method thereof. The preparation method provided by the present invention obtains an acrylate solution polymer with a narrow molecular weight distribution by limiting the polymerization reaction temperature and the introduction rate of the reactant solution for program control.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing an acrylic acid ester solution polymer, comprising the following steps:

[0007] The acrylic acid ester monomer solution and the initiator solution are respectively introduced into a tubular reactor for polymerization reaction, the temperature of the polymerization reaction is programmed controlled according to Formula 1, and the introduction rate of the reactant solution is programmed controlled according to Formula 2 to obtain the acrylic acid ester solution polymer; the reactant solution includes the acrylic acid ester monomer solution and the initiator solution;

[0008] T(t)=T start+a(t - t start ) Equation 1;

[0009] In the said Equation 1, T start is the initial temperature, t start is the initial time for heating or cooling, T(t) is the temperature of the polymerization reaction. By controlling T start , t start , t and a, the change range of the said T(t) is 65 - 80 °C;

[0010] In the said Equation 1 where T end is the final temperature, t end is the termination time for heating or cooling;

[0011]

[0012] In the said Equation 1 and Equation 2, t is the reaction time, with the unit of min;

[0013] In the said Equation 2, A, B, C, k 1 , k 2 , t 0 are natural numbers, v(t) is the pumping rate of the reactant solution. By controlling A, B, C, k 1 , k 2 , t 0 the change range of the said v(t) is 0.5 - 6 cm / s.

[0014] Preferably, in the said Equation 2:

[0015]

[0016] Preferably, the concentration of the mixed solution system obtained after the acrylate monomer solution and the initiator solution are respectively introduced into the tubular reactor is 0.5 - 5 mol / L.

[0017] Preferably, the molar ratio of the acrylate monomer to the initiator in the mixed solution system is 10 - 500:1.

[0018] Preferably, the acrylate monomer solution includes one or more of methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution, methyl 2 - methylacrylate solution and ethyl 2 - methylacrylate solution.

[0019] Preferably, the pumping speed ratio of the acrylate monomer solution to the initiator solution is 0.55 - 1.00:0.60 - 0.80.

[0020] Preferably, the acrylate monomer solution includes methyl acrylate solution, ethyl acrylate solution and butyl acrylate solution, and the pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution is 0.80-1.00:0.70-0.90:0.55-0.75:0.60-0.80.

[0021] Preferably, it further includes material circulation for the system obtained from the polymerization reaction, and the circulation ratio of the material circulation is 1:5-1:30 。

[0022] Preferably, a static mixer and an ultrasonic reactor are successively connected to the front end of the tubular reactor, the output power of the ultrasonic reactor is 0.5-50 kW, and the output ultrasonic frequency is 10-100 kHz.

[0023] The present invention also provides an acrylate solution polymer prepared by the preparation method described in the above technical solution, and the molecular weight distribution of the acrylate solution polymer is 1.20-1.30.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] Based on polymerization reaction kinetics and on the basis of kinetic mechanism, the present invention performs programmed control by limiting the temperature of the polymerization reaction and the feeding rate of the reactant solution, and obtains an acrylate solution polymer with a narrow molecular weight distribution.

[0026] Furthermore, the present invention limits that the acrylate monomer solution includes one or more of methyl acrylate solution (MAA solution), ethyl acrylate solution (EA solution), butyl acrylate solution (BA solution), methyl methacrylate solution (MMA solution) and ethyl methacrylate solution, and can use different types of acrylate monomers to prepare acrylate solution polymers.

[0027] Furthermore, the present invention limits the concentrations and pumping speed ratios of the acrylate monomer solution and the initiator solution, so that the polymerization chain growth process is effectively controlled, further reducing the molecular weight distribution of the acrylate solution polymer and achieving a lower molecular weight dispersity.

[0028] The data of the examples show that the molecular weight distribution of the acrylate solution polymer prepared by the present invention is 1.20-1.30, and the molecular weight distribution is narrow.

[0029] At the same time, the present invention limits that the polymerization reaction is carried out in a tubular reactor, and the tubular reactor has the excellent advantages of heat transfer and mass transfer, can eliminate the excess heat effect, make the polymerization reaction stable, and further reduce the molecular weight distribution.

[0030] Furthermore, the present invention also defines a material recycle for the system obtained from the polymerization reaction, which can further eliminate the excess heat effect brought by the polymerization reaction, make the polymerization reaction stable, and further reduce the molecular weight distribution.

[0031] Furthermore, the present invention also defines that a static mixer and an ultrasonic reactor are successively connected to the front end of the tubular reactor, which can make the reaction stable and further reduce the molecular weight distribution. Description of the Drawings

[0032] Figure 1 Taking the acrylate monomer solution including methyl acrylate solution, ethyl acrylate solution and butyl acrylate solution as an example, it is a flow chart of the preparation method of the acrylate solution polymer in the embodiment of the present invention;

[0033] Figure 2 It is the change curve of v(t) and t in Example 1;

[0034] Figure 3 It is the change curve of T(t) and t in Example 1;

[0035] Figure 4 It is the curve of the weight average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 1 changing with time;

[0036] Figure 5 It is the curve of the average monomer conversion rate changing with time in Example 1;

[0037] Figure 6 It is the change curve of v(t) and t in Example 2;

[0038] Figure 7 It is the curve of the weight average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 2 changing with time;

[0039] Figure 8 It is the curve of the average conversion rate of two monomers changing with time in Example 2;

[0040] Figure 9 It is the change curve of v(t) and t in Example 3;

[0041] Figure 10 It is the curve of the weight average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 3 changing with time;

[0042] Figure 11 It is the curve of the average conversion rate of three monomers changing with time in Example 3;

[0043] Figure 12Curves showing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 4 with time;

[0044] Figure 13 Curves showing the variation of the average conversion rates of the three monomers in Example 4 with time;

[0045] Figure 14 Curves showing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 5 with time;

[0046] Figure 15 Curves showing the variation of the average conversion rates of the three monomers in Example 5 with time;

[0047] Figure 16 Curves showing the variation of v(t) with t in Comparative Example 1;

[0048] Figure 17 Curves showing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 1 with time;

[0049] Figure 18 Curves showing the variation of the average conversion rates of the three monomers in Comparative Example 1 with time;

[0050] Figure 19 Curves showing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 2 with time;

[0051] Figure 20 Curves showing the variation of the average conversion rates of the three monomers in Comparative Example 2 with time;

[0052] Figure 21 Curves showing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 3 with time;

[0053] Figure 22 Curves showing the variation of the average conversion rates of the three monomers in Comparative Example 3 with time;

[0054] Figure 23 Curves showing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 4 with time;

[0055] Figure 24 Curves showing the variation of the average conversion rates of the three monomers in Comparative Example 4 with time;

[0056] Figure 25 Curves for comparing the variation of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymers prepared in Comparative Example 5 and Example 1 with time;

[0057] Figure 26The contrast curves of the average monomer conversion rate changing with time in Comparative Example 5 and Example 1;

[0058] Figure 27 The curves of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer obtained by physically increasing the temperature of the tubular reactor in Example 1 changing with time;

[0059] Figure 28 The curves of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 6 changing with time;

[0060] Figure 29 The curves of the average conversion rates of three monomers in Comparative Example 6 changing with time. Detailed implementation mode

[0061] The present invention provides a preparation method of an acrylate solution polymer, comprising the following steps:

[0062] Feeding an acrylate monomer solution and an initiator solution into a tubular reactor respectively for polymerization reaction, controlling the temperature of the polymerization reaction according to Formula 1 in a programmed manner, and controlling the feeding rate of the reactant solution according to Formula 2 in a programmed manner to obtain the acrylate solution polymer; the reactant solution includes the acrylate monomer solution and the initiator solution;

[0063] T(t) = T start +a(t - t start ) Formula 1;

[0064] In the said Formula 1, T start is the initial temperature, t start is the initial time for heating or cooling, T(t) is the temperature of the polymerization reaction, and by controlling T start , t start , t and a, the change range of the said T(t) is 65 - 80 °C;

[0065] In the said Formula 1 where T end is the final temperature, t end is the termination time for heating or cooling;

[0066]

[0067] In the said Formulas 1 and 2, t is the reaction time, with the unit of min;

[0068] In the said Formula 2, A, B, C, k 1 , k 2 , t 0 are natural numbers, v(t) is the pumping rate of the reactant solution, and by controlling A, B, C, k 1, k 2 , t 0 Make the change range of the v(t) be 0.5 - 6 cm / s.

[0069] In the present invention, the formula 2 preferably includes:

[0070]

[0071] Taking the k 1 ∈[0.01, 0.1] as an example to illustrate the value ranges of A, B, C, k 1 , k 2 , t 0 , t, the value range of k 1 ∈[0.01, 0.1] means that the value range of k 1 is 0.01 - 0.1.

[0072] In the present invention, the concentration of the mixed solution system obtained after the acrylate monomer solution and the initiator solution are respectively introduced into the tubular reactor is preferably 0.5 - 5 mol / L, and specifically can be 0.5, 1, 1.35, 1.5, 2, 2.5, 3, 3.5, 4.013, 4.5 or 5 mol / L.

[0073] In the present invention, the molar ratio of the acrylate monomer to the initiator in the mixed solution system is preferably 10 - 500:1, and specifically can be 10:1, 50:1, 100:1, 168.75:1, 200:1, 300:1, 400:1.3, 400:1 or 500:1. The concentration of the acrylate monomer solution will affect the chain growth rate and the molecular weight distribution. When the monomer concentration is high, the chain growth reaction rate is accelerated, and it is easy to form polymers with higher molecular weights. However, if the monomer concentration is too high, the viscosity of the reaction system may increase, diffusion is limited, the possibility of chain termination increases, and finally the molecular weight distribution becomes wider. At low monomer concentrations, the opportunity for chain growth decreases, the reaction is incomplete, and the molecular weight distribution may be even wider. In the present invention, at an appropriate monomer concentration, the molecular weight distribution is usually narrower.

[0074] In the present invention, the pumping speed ratio of the acrylate monomer solution to the initiator solution is preferably 0.55 - 1.00:0.60 - 0.80.

[0075] In the present invention, the acrylate monomer solution preferably comprises one or more of methyl acrylate solution (MAA solution), ethyl acrylate solution (EA solution), butyl acrylate solution (BA solution), methyl methacrylate solution (MMA solution), and ethyl methacrylate solution, and acrylate solution polymers can be prepared using different types of acrylate monomers. More preferably, it is methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution, methyl methacrylate solution, ethyl methacrylate solution, or two, three, four, or five of methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution, methyl methacrylate solution, and ethyl methacrylate solution. When preferably two, it is more preferably methyl acrylate solution and ethyl acrylate solution, or more preferably methyl acrylate solution and butyl acrylate solution, or more preferably ethyl acrylate solution and butyl acrylate solution. When preferably three, it is more preferably methyl acrylate solution, ethyl acrylate solution, and butyl acrylate solution.

[0076] In the present invention, when the acrylate monomer solution is preferably three, the concentration of the methyl acrylate solution is preferably 0.30 - 0.60 mol / L, specifically it can be 0.30, 0.40, 0.50, or 0.60 mol / L; the concentration of the ethyl acrylate solution is preferably 0.25 - 0.55 mol / L, specifically it can be 0.25, 0.35, 0.45, or 0.55 mol / L; the concentration of the butyl acrylate solution is preferably 0.20 - 0.50 mol / L, specifically it can be 0.20, 0.30, 0.40, or 0.50 mol / L.

[0077] In the present invention, the concentration of the initiator solution is 0.005 - 0.020 mol / L, specifically it can be 0.005, 0.008, 0.010, 0.015, or 0.020 mol / L; the concentration of the initiator solution directly determines the initial concentration of free radicals in the reaction system. If the concentration of the initiator solution is higher, the free radical concentration increases, the chain initiation rate increases, but at the same time it will also lead to an increase in the chain termination rate, thus generating more polymers with low molecular weight and a wider molecular weight distribution. A lower concentration of the initiator solution helps to maintain the activity balance of free radicals, thereby achieving a narrow molecular weight distribution.

[0078] In the present invention, the initiator in the initiator solution preferably comprises azobisisobutyronitrile (AIBN).

[0079] In the present invention, when the acrylate monomer solution is preferably three kinds, the pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution is preferably 0.80 to 1.00: 0.70 to 0.90: 0.55 to 0.75: 0.60 to 0.80.

[0080] In the present invention, methyl acrylate, ethyl acrylate and butyl acrylate are polar, and their polymerization reaction rates are closely related to the electronic effects of the monomers. The higher the electron density of the monomer, usually the faster its polymerization reaction rate. Among them, the influence of methyl on the polymerization reaction rate is smaller than that of ethyl and butyl, because methyl is a relatively small and non-polar group, and relative to the longer alkyl chains (such as ethyl and butyl), it has less influence on the active center of the polymerization reaction. Therefore, smaller side groups usually result in a faster reaction rate. Due to the influence of methyl, methyl acrylate has a lower polarity, resulting in a relatively high reaction activity during polymerization. While ethyl acrylate and butyl acrylate have relatively lower polarities due to the larger alkyl chains, so their reaction rates are usually slower than that of methyl acrylate. Based on polymerization reaction kinetics and on the basis of the kinetic mechanism, the present invention combines and defines the feeding according to the pumping speeds of the three monomers of methyl acrylate, ethyl acrylate and butyl acrylate, so that the polymerization chain growth process is effectively controlled, the molecular weight distribution of the acrylate solution polymer is reduced, and a lower molecular weight dispersity is achieved; and the pumping speed of the initiator solution is controlled within the above range. On the one hand, it limits the highest concentration in the tubular reactor to prevent the occurrence of large molecular weight polymer blocking the pipe and preventing the reaction from proceeding further, while ensuring that the obtained molecular weight distribution is relatively narrow.

[0081] In the present invention, the solvents of the acrylate monomer solution and the initiator solution are both preferably propylene glycol methyl ether acetate (PGMEA, PMA). Using propylene glycol methyl ether acetate as the solvent can reduce the system viscosity and pressure drop, improve the experimental safety, and avoid the possible pipe blocking phenomenon in the tubular reactor.

[0082] Taking the acrylate monomer solution including methyl acrylate solution, ethyl acrylate solution and butyl acrylate solution as an example, Figure 1 This is the flow chart of the preparation method of the acrylate solution polymer in the embodiment of the present invention. The methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution are respectively placed in an eggplant-shaped flask. After vacuum treatment, nitrogen is filled so that the materials are not in contact with air during the reaction process. Then, the static mixer, oil bath and ultrasonic reactor are turned on to make the tubular reactor reach the polymerization reaction temperature. The computer control program is turned on to pump the three monomer solutions and the initiator solution into the tubular reactor through a peristaltic pump for polymerization reaction. When the reaction product flows out at the outlet, the material circulation pump is turned on to realize material circulation.

[0083] In the present invention, the formula 1 is a piecewise function equation in which the reaction temperature varies with time, and the specific piecewise function equation is as shown in formula 3:

[0084]

[0085] In the formula 3, T 1 is 70 to 75 °C, T 2 is 65 to 70 °C, T 3 is 68 to 73 °C, T 4 is 70 to 75 °C, T 5 is 75 to 80 °C.

[0086] In a specific embodiment of the present invention, it is preferred that the

[0087]

[0088] The change range of the t is 0 to 160 min, and the change range of the v(t) is 0.72 to 3.00 cm / s;

[0089] The pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution is 0.90:0.80:0.65:0.70, 0.80:0.75:0.55:0.60 or 1.00:0.90:0.75:0.80.

[0090] In a specific embodiment of the present invention, it is preferred that the

[0091]

[0092]

[0093]

[0093] The change range of the t is 0 to 160 min, and the change range of the v(t) is 2.25 to 3.00 cm / s;

[0094] In a specific embodiment of the present invention, it is preferred that the

[0095]

[0096] The change range of the t is 0 to 160 min, and the change range of the v(t) is 2.25 to 3.00 cm / s;

[0097] The pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution is 0.90:0.80:0.65:0.70.

[0098] In the present invention, the acrylate monomer solution and the initiator solution are preferably added into the tubular reactor respectively through peristaltic pumps by means of programmed control.

[0099] In a specific embodiment of the present invention, the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution are respectively added into the tubular reactor through four peristaltic pumps by means of programmed control based on polymerization reaction kinetics.

[0100] In the present invention, the inner lining of the tubular reactor is preferably polytetrafluoroethylene, so that metal ions are not introduced during the polymerization reaction process; and the use of a tubular reactor can make the temperature control of the polymerization reaction more accurate.

[0101] In the present invention, the tubular reactor is preferably heated at a constant temperature by an oil bath to maintain the temperature of the polymerization reaction.

[0102] In the present invention, a static mixer and an ultrasonic reactor are preferably connected in sequence at the front end of the tubular reactor. That is, before the acrylate monomer solution and the initiator solution are introduced into the tubular reactor, they are preferably mixed in the static mixer first. The function of the static mixer is to make the raw materials mix evenly, and then introduced into the ultrasonic reactor. The introduction of the ultrasonic reactor can generate cavitation, promote the generation of free radicals, thereby accelerating the polymerization reaction, generate a high-energy region in a short time and promote the reaction to occur, which is beneficial to improving the reaction rate. At the same time, the shear force and cavitation generated by ultrasound in the liquid make the interaction between molecules more active; and the static mixer and the ultrasonic reactor make the raw materials evenly distributed in the tubular reactor for quantitative reaction.

[0103] In the present invention, the output power of the ultrasonic reactor is preferably 0.5 - 50 kW, specifically it can be 0.5, 1, 10, 20, 30, 40 or 50 kW, and the output ultrasonic frequency is preferably 10 - 100 kHz, specifically it can be 10, 20, 30, 40, 50, 60, 70, 80, 90 or 100 kHz. The higher the ultrasonic frequency, the more evenly the reactants are mixed in the reactor, the lower the molecular weight of the obtained polymer, the more uniform the product, and it can improve the mass transfer and heat transfer efficiency of the reactor.

[0104] In the present invention, it is preferred to connect a static mixer at the front end of the tubular reactor and turn on the ultrasonic reactor while feeding.

[0105] In the present invention, it is preferably further included to perform material circulation on the system obtained from the polymerization reaction. The circulation ratio of the material circulation is preferably 1:5 to 1:30, specifically it can be 1:5, 1:10, 1:15, 1:20, 1:25 or 1:30. The function of the material circulation is to cool down the reaction system and at the same time remove the excess heat brought by the ultrasonic reactor. The circulation ratio refers to the ratio of the circulation flow rate to the feed flow rate. For the case of generating a higher heat effect, the effect of removing the heat effect can be achieved by increasing the circulation ratio.

[0106] In the present invention, the flow rate of the liquid during the material circulation is preferably 0.7 to 0.95 cm / s, specifically it can be 0.7, 0.8, 0.9 or 0.95 cm / s. The circulation ratio is directly proportional to the flow rate of the liquid during the material circulation. Therefore, for the case of generating a higher heat effect, a high circulation ratio is required to achieve the removal of the heat effect, and thus a larger flow rate of the liquid during the material circulation is required to achieve this.

[0107] In a specific embodiment of the present invention, it is preferably to separately place the acrylate monomer solution and the initiator solution into an eggplant-shaped flask. After both are subjected to vacuum treatment, nitrogen is filled in to ensure that the materials are not in contact with air during the reaction process. Then, the static mixer, the oil bath and the ultrasonic reactor are turned on to make the tubular reactor reach the temperature of the polymerization reaction. The computer control program is turned on to pump the monomer solution and the initiator solution into the tubular reactor through a peristaltic pump to carry out the polymerization reaction. When the reaction product flows out at the outlet, the material circulation pump is turned on to realize the material circulation.

[0108] The present invention also provides an acrylate solution polymer prepared by the preparation method of the above technical solution. The molecular weight distribution of the acrylate solution polymer is 1.20 to 1.30, specifically it can be 1.21, 1.22, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29 or 1.30.

[0109] The acrylate solution polymer of the present invention has the following advantages due to its narrow molecular weight distribution:

[0110] 1. Improvement in physical property stability: Uniform mechanical properties. A narrow molecular weight distribution means that the lengths of all polymer chains are similar, and mechanical properties such as tensile strength and elastic modulus are uniform, reducing property fluctuations caused by long or short chains; Higher mechanical strength and toughness. High molecular weight chains have higher tensile strength and wear resistance. When the molecular weight distribution is narrow, the mechanical properties of the polymer are more easily predicted and controlled, which is suitable for applications requiring higher strength and toughness.

[0111] 2. Controllability of thermal properties: Uniform thermal behavior, with a narrow PDI resulting in relatively consistent melting points or glass transition temperatures (Tg) of polymers, helps achieve more stable thermal properties during processing and use, reducing local thermal instability caused by molecular weight differences;

[0112] 3. Improvement of processing properties: Predictable processing behavior, a narrow PDI makes the melt rheological properties of polymers more stable, with small viscosity changes during processing, easy to control, which can improve processing efficiency and ensure more consistent processing results; Improve processing stability. During processes such as extrusion, injection molding, and spinning, polymers with a narrow PDI are easier to control fluidity, reducing flow instability and defects caused by a wide molecular weight distribution;

[0113] 4. Consistency of surface properties: Uniform surface properties. For applications that require specific surface energy or surface modification (such as coatings, adhesives, etc.), a narrow PDI makes the surface properties more consistent, showing better adhesion, wettability, etc.;

[0114] 5. Consistency of chemical reactivity: Consistent reactivity. For polymers that require further chemical modification or crosslinking (such as curing of polymer solutions, UV curing, etc.), a narrow PDI can ensure the consistency of reactions, avoiding non-uniform material properties caused by differences in reactivity between long chains and short chains.

[0115] The present invention also provides the application of the acrylate solution polymer in a photoresist, which is achieved through the photosensitivity of the acrylate solution polymer under ultraviolet radiation and its compatibility with other components (including sensitizers, crosslinking agents, etc.). Its advantages include: 1. Excellent optical properties: The acrylate solution polymer has good transparency, especially in the ultraviolet region, which enables it to effectively transmit light energy during the lithography process and ensure the uniformity of the exposure process. 2. Adjustable molecular weight and viscosity: By adjusting the molecular weight of the acrylate solution polymer, properties such as the solubility, viscosity, and film thickness of the photoresist can be controlled, thereby optimizing the coating and development characteristics of the photoresist. 3. Photosensitivity and crosslinking characteristics: The acrylate solution polymer can react with a photoinitiator and crosslink under ultraviolet light irradiation to form a part that is insoluble in the developer, enabling the pattern to be stably retained during the development process. By controlling the ratio of acrylate monomers and crosslinking agents, the exposure and development behavior of the photoresist can be adjusted. 4. Strong adaptability: The acrylate solution polymer can be well compatible with other photoresist components (such as sensitizers, plasticizers, etc.) to adjust its properties to meet different process requirements. 5. Improved pattern resolution: The acrylate solution polymer has a narrow molecular weight distribution, which means that most molecular chains have similar lengths, and the fluidity and viscosity of the photoresist are more uniform. This uniformity helps to precisely control the edges of the pattern during the exposure and development processes, improving the resolution. During the lithography process, a narrow molecular weight distribution ensures that the microstructures formed by the photoresist after exposure are more stable and clear, reducing pattern blur and distortion caused by different molecular chain lengths. 6. Improved thickness uniformity of the photoresist: During the photoresist coating process, the acrylate solution polymer with a smaller PDI, due to its more uniform molecular weight distribution, results in a more uniform film thickness, avoiding exposure inconsistencies caused by uneven film thickness and ensuring the stability of the lithography process and high-quality pattern transfer. 7. Optimization of development performance: The acrylate solution polymer with a smaller PDI has more uniform solubility and swelling properties during the development process, enabling the photoresist to quickly and uniformly remove the uncrosslinked part in the developer, avoiding phenomena such as incomplete development or local overdevelopment, thereby enhancing the edge sharpness and quality of the pattern. 8. Improved processing stability: The acrylate solution polymer with a smaller PDI has more stable rheological properties, that is, during processes such as coating, exposure, and development, the viscosity, fluidity, etc. of the photoresist are more consistent, which can reduce uncertainties during processing and make process control more precise. 9. Improved photosensitivity and crosslinking: Polymer chains with a narrow molecular weight distribution have similar lengths, which means that each molecule can uniformly participate in the crosslinking reaction after exposure, enhancing the photosensitivity and crosslinking degree of the photoresist and improving the pattern retention rate and quality.10. Higher anti-pollution and durability: Due to the consistent molecular chain length, acrylate solution polymers with a smaller PDI usually have better chemical corrosion resistance and anti-pollution ability, and can maintain good performance during long-term process treatment.

[0116] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0117] In the embodiments and comparative examples of the present invention, the average conversion rates of the three monomers over time were measured by gas chromatography (GC), and the molecular weights and molecular dispersities of the acrylate solution polymers were measured by Waters 1525 / 2414 gel permeation chromatography (GPC).

[0118] Gas chromatography (GC) determination conditions

[0119] Carrier gas: High-purity hydrogen (99.999% purity), using a SH-RTX-1 type capillary chromatographic column (30m×0.25mm×0.25μm), and the flow rate of the chromatographic column is 1.0 mL / min. The inlet temperature is 250°C; the detection port temperature is 300°C; the split ratio is 10:1; the column temperature is 80°C, held for 2 min, then increased to 150°C at a rate of 5°C / min and held for 3 min, and then increased to 250°C at a rate of 20°C / min and held for 5 min.

[0120] Waters 1525 / 2414 gel permeation chromatography (GPC) method determination conditions

[0121] A tetrahydrofuran (THF) solution of the polymer with a concentration of 3 mg / mL was passed through three series-connected GPC columns of 500, 1000, and at a flow rate of 1 mL / min at 35°C to obtain a standard curve using 10 narrow-distribution PS standards with molecular weights ranging from 0.5 to 46.0 kg / mol.

[0122] Example 1

[0123] Prepare an acrylate solution polymer, including the following steps:

[0124] Ethyl acrylate and azobisisobutyronitrile were respectively dissolved in PMA and placed in an eggplant-shaped flask. The concentration of the ethyl acrylate solution was 1.35 mol / L, and the concentration of the azobisisobutyronitrile solution was 0.008 mol / L. After vacuum treatment of both the ethyl acrylate solution and the initiator solution, nitrogen was filled in to ensure that the materials were never in contact with air during the reaction. Then, the static mixer, the oil bath (which can achieve programmed temperature control), and the ultrasonic reactor (output power: 10 kW, ultrasonic frequency: 30 kHz) were turned on to bring the tubular reactor to the initial polymerization reaction temperature (75 °C). The computer control program was turned on to make the tubular reactor perform segmented programmed heating (or cooling) according to the reaction temperature vs. time equation (Equation 1), and the ethyl acrylate solution and the initiator solution were pumped into the tubular reactor for polymerization reaction through two peristaltic pumps according to the total pump-in rate vs. time equation (Equation 4). The initial total pump-in rate was 2.32 cm / s. When the reaction proceeded for 10 min (when the reaction temperature dropped to Figure 3 the first temperature plateau in

[0125] In Equation 4, at the beginning of the polymerization reaction, the rate is relatively fast, and the total pump-in rate should be reduced as much as possible to reduce local heat release. In the later stage of the polymerization reaction, the total pump-in rate is increased to increase the monomer conversion rate. Figure 2 is the change curve of v(t) and t in Example 1.

[0126] The piecewise function change equation of the reaction temperature vs. time in Example 1 is as shown in Equation 7. Figure 3 is the change curve of T(t) and t in Example 1.

[0127]

[0128] It can be seen that the initial polymerization reaction temperature is relatively high, which causes the initiator to decompose, enabling chain initiation to proceed. A large amount of heat is released during chain growth, and the reaction temperature needs to be reduced to remove the polymerization reaction heat in a timely manner. Then, the temperature is increased to increase the reaction rate and the monomer conversion rate.

[0129] Figure 4 is the curve of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 1 vs. time. Figure 5 is the curve of the average monomer conversion rate vs. time in Example 1. It can be seen that the monomer conversion rate is 99.17%, the weight-average molecular weight (Mw) of the obtained acrylate solution polymer is 38577 g / mol, and the molecular weight distribution is 1.20.

[0130] Example 2

[0131] Prepare an acrylate solution polymer, including the following steps:

[0132] Dissolve methyl acrylate, ethyl acrylate and azobisisobutyronitrile in PMA respectively, and put them into an eggplant-shaped flask. The concentration of the methyl acrylate solution is 2.10 mol / L, the concentration of the ethyl acrylate solution is 1.90 mol / L, and the concentration of the azobisisobutyronitrile solution is 0.013 mol / L. After vacuum treatment of the methyl acrylate solution, ethyl acrylate solution and initiator solution, fill them with nitrogen so that the materials are always not in contact with air during the reaction. Then turn on the static mixer, oil bath (programmable temperature control) and ultrasonic reactor (output power is 10 kW, ultrasonic frequency is 30 kHz) to make the tubular reactor reach the temperature of the initial polymerization reaction (75 °C). Turn on the computer control program to make the tubular reactor perform segmented programmed heating (or cooling) according to the reaction temperature change equation with time (Equation 1), so that the methyl acrylate solution, ethyl acrylate solution and initiator solution are pumped into the tubular reactor through three peristaltic pumps according to the equation of the total pumping rate with time (Equation 5) for polymerization reaction. The initial total pumping rate is 2.32 cm / s. When the reaction proceeds to 10 min (when the reaction temperature drops to the first temperature plateau), turn on the material circulation pump to realize material circulation (flow rate is 0.7 cm / s, circulation ratio is 1:30) to obtain an acrylate solution polymer, where the pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution and azobisisobutyronitrile solution is 0.90:0.80:0.70, and the change range of v(t) is 0.72 - 3.00 cm / s.

[0133] Figure 6 It is the change curve of v(t) and t in Example 2.

[0134] Figure 7 It is the curve of the change of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 2 with time, Figure 8 It is the curve of the change of the average conversion rate of the two monomers with time in Example 2. It can be seen that the average conversion rate of the two monomers is 99.23%, the weight-average molecular weight of the obtained acrylate solution polymer is 38479 g / mol, and the molecular weight distribution is 1.23.

[0135] Example 3

[0136] Prepare an acrylate solution polymer, including the following steps:

[0137] Methyl acrylate, ethyl acrylate, butyl acrylate and azobisisobutyronitrile were respectively dissolved in PMA and placed in an eggplant-shaped flask. The concentrations of the methyl acrylate solution, ethyl acrylate solution and butyl acrylate solution were 0.50 mol / L, 0.45 mol / L and 0.40 mol / L respectively, and the concentration of the azobisisobutyronitrile solution was 0.008 mol / L. After vacuum treatment of the three monomer solutions and the initiator solution, nitrogen was filled to ensure that the materials were not in contact with air during the reaction. Then, the static mixer, oil bath (programmable temperature control) and ultrasonic reactor (output power: 10 kW, ultrasonic frequency: 30 kHz) were turned on to make the tubular reactor reach the initial polymerization reaction temperature (75 °C). The computer control program was turned on to make the tubular reactor perform segmented programmed temperature increase (or decrease) according to the reaction temperature change equation with time (Equation 1). The three monomer solutions and the initiator solution were pumped into the tubular reactor through four peristaltic pumps according to the equation of the total pumping rate with time (Equation 6) for polymerization reaction. The initial total pumping rate was 2.32 cm / s. When the reaction proceeded to 10 min (when the reaction temperature dropped to the first temperature plateau), the material circulation pump was turned on to achieve material circulation (flow rate: 0.7 cm / s, circulation ratio: 1:15), and an acrylate solution polymer was obtained. The pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and azobisisobutyronitrile solution was 0.90:0.80:0.65:0.70, and the variation range of v(t) was 0.72 - 3.00 cm / s.

[0138] Figure 9 It is the change curve of v(t) and t in Example 3.

[0139] Figure 10 It is the curve of the change of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 3 with time. Figure 11 It is the curve of the change of the average conversion rate of the three monomers with time in Example 3. It can be seen that the average conversion rate of the three monomers is 99.19%, the weight-average molecular weight of the obtained acrylate solution polymer is 38421 g / mol, and the molecular weight distribution is 1.29.

[0140] Example 4

[0141] It is the same as Example 3, with the only difference being that the pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and azobisisobutyronitrile solution is 0.80:0.75:0.55:0.60.

[0142] Figure 12 It is the curve of the change of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 4 with time. Figure 13It is the curve of the average conversion rate of the three monomers varying with time in Example 4. It can be seen that the average conversion rate of the three monomers is 99.42%, the weight-average molecular weight of the obtained acrylate solution polymer is 38434 g / mol, and the molecular weight distribution is 1.30.

[0143] Example 5

[0144] Same as Example 3, the only difference is that: the pumping rates of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution, and azobisisobutyronitrile solution are in the ratio of 1.00:0.90:0.75:0.80.

[0145] Figure 14 It is the curve of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Example 5 varying with time. Figure 15 It is the curve of the average conversion rate of the three monomers varying with time in Example 5. It can be seen that the average conversion rate of the three monomers is 99.57%, the weight-average molecular weight of the obtained acrylate solution polymer is 38437 g / mol, and the molecular weight distribution is 1.28.

[0146] Comparative Example 1

[0147] Same as Example 3, the only difference is that: the equation of the total pumping rate varying with time is Equation 8. Figure 16 It is the curve of v(t) varying with t in Comparative Example 1, and the variation range of v(t) is 2.50 - 7.00 cm / s.

[0148]

[0149] Figure 17 It is the curve of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 1 varying with time. Figure 18 It is the curve of the average conversion rate of the three monomers varying with time in Comparative Example 1. It can be seen that the average conversion rate of the three monomers is 98.23%, the weight-average molecular weight of the obtained acrylate solution polymer is 38453 g / mol, and the molecular weight distribution is 2.34.

[0150] Comparative Example 2

[0151] Same as Example 3, the only difference is that: the pumping rate is stabilized at 6 cm / s, and a computer control program is not used to regulate the rate of the peristaltic pump.

[0152] Figure 19 It is the curve of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 2 varying with time. Figure 20It is the curve of the average conversion rate of the three monomers changing with time in Comparative Example 2. It can be seen that the average conversion rate of the three monomers is 97.16%, the weight-average molecular weight of the obtained acrylate solution polymer is 38331 g / mol, and the molecular weight distribution is 2.71.

[0153] Comparative Example 3

[0154] It is the same as Example 3, except that: the pumping speed is stabilized at 4 cm / s, and the computer control program is not used to regulate the rate of the peristaltic pump.

[0155] Figure 21 It is the curve of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 3 changing with time. Figure 22 It is the curve of the average conversion rate of the three monomers changing with time in Comparative Example 3. It can be seen that the average conversion rate of the three monomers is 99.06%, the weight-average molecular weight of the obtained acrylate solution polymer is 38422 g / mol, and the molecular weight distribution is 2.52.

[0156] Comparative Example 4

[0157] It is the same as Example 3, except that: the three monomers methyl acrylate, ethyl acrylate and butyl acrylate and the initiator are dissolved in the same eggplant-shaped flask, and only one peristaltic pump is used to pump the three monomers and the initiator into the tubular reaction system. The pumping speed is stabilized at 4.0 cm / s, and the computer control program is not used to regulate the rate of the peristaltic pump.

[0158] Figure 23 It is the curve of the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 4 changing with time. Figure 24 It is the curve of the average conversion rate of the three monomers changing with time in Comparative Example 4. It can be seen that the average conversion rate of the three monomers is 98.74%, the weight-average molecular weight of the obtained acrylate solution polymer is 38582 g / mol, and the molecular weight distribution is 2.70.

[0159] Comparative Example 5

[0160] It is the same as Example 1, except that: the tubular reactor is replaced with a kettle reactor.

[0161] Figure 25The comparative curves of the changes in the weight-average molecular weight and molecular weight distribution of the acrylate solution polymers prepared in Comparative Example 5 and Example 1 over time show that the weight-average molecular weight obtained in the batch reactor is smaller, at 23,392 g / mol, and the molecular weight distribution is wider, at 2.45. The final weight-average molecular weight of the tubular reactor in Example 1 is 38,577 g / mol, and the molecular weight distribution is narrower, at 1.20. The main reason for the higher weight-average molecular weight of the product obtained in the batch reactor is that the polymerization reaction process releases a large amount of heat, and the higher the temperature, the lower the weight-average molecular weight of the polymer obtained. Figure 26 The comparative curves of the average monomer conversion rate over time in Comparative Example 5 and Example 1 show that after 6 hours of reaction in the batch reactor, the average monomer conversion rate is 93%, while in the tubular reactor, it reaches nearly 100% in 3 hours, doubling the production efficiency.

[0162] It was measured that the reaction temperature inside the batch reactor was higher than the actual experimental temperature. Therefore, the operation was repeated in the tubular reactor of Example 1, and physical heating was increased to raise the temperature of the polymerization reaction to the actual experimental temperature. The curves of the changes in the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer over time are as follows Figure 27 It can be seen that after physical heating is applied to the tubular reactor, the weight-average molecular weight is 23,297 g / mol, which is very close to the weight-average molecular weight obtained in the batch reactor, and the PDI is narrow, at 1.25. From this, it can be seen that the tubular reactor effectively solves the problem of poor temperature control in the batch reactor. The batch reactor cannot remove heat in time, while the tubular reactor has good mass and heat transfer effects, can carry out polymerization reactions at a specified temperature, and has no heating effect; moreover, the PDI obtained from repeated experiments is maintained between 1.20 and 1.30, which is much smaller than the result of the wide molecular weight in the batch reactor.

[0163] Comparative Example 6

[0164] It is the same as Example 3, except that: an ultrasonic reactor is not used.

[0165] Figure 28 The curves of the changes in the weight-average molecular weight and molecular weight distribution of the acrylate solution polymer prepared in Comparative Example 6 over time Figure 29 The curves of the average conversion rate of the three monomers over time in Comparative Example 6 show that the average conversion rate of the three monomers is 88.23%, and the weight-average molecular weight of the obtained acrylate solution polymer is 40,453 / mol, and the molecular weight distribution is 2.41.

[0166] Comparing Example 3 and Comparative Example 6 shows that the ultrasonic reactor makes the reactants mix evenly in the reactor, and the product is more homogeneous; without the ultrasonic reactor, the average conversion rate of the three monomers decreases significantly, and the ultrasonic reactor improves the mass and heat transfer efficiency of the reactor.

[0167] The above are only the preferred embodiments of the present invention and do not impose any formal limitations on the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing an acrylic acid ester solution polymer, characterized in that: The following steps are involved: The acrylic acid ester monomer solution and the initiator solution are respectively introduced into a tubular reactor for polymerization reaction, the temperature of the polymerization reaction is programmed controlled according to Formula 1, and the introduction rate of the reactant solution is programmed controlled according to Formula 2 to obtain the acrylic acid ester solution polymer; the reactant solution includes the acrylic acid ester monomer solution and the initiator solution; T(t)=T start +a(tt start ) Formula 1; In the formula 1, T start is the initial temperature, t start is the initial time of heating or cooling, T(t) is the temperature of the polymerization reaction, and by controlling T start ,t start , t and a make the range of T(t) be 65-80°C; In the formula 1 Where T end is the final temperature, t end The end time of heating or cooling; In formulas 1 and 2, t is the reaction time, in min; In the formula 2, A, B, C, k1, k2, and t0 are natural numbers, and v(t) is the pumping rate of the reactant solution. By controlling A, B, C, k1, k2, and t0, the variation range of v(t) is 0.5 to 6 cm / s.

2. The preparation method according to claim 1, characterized in that: In the formula 2: C∈[0.5，6] k1∈[0.01,0.1],k2∈[0.0001,0.005],t0∈[10,50],t∈[0,160].

3. The preparation method according to claim 1, characterized in that: The concentration of the mixed solution system obtained after the acrylic acid ester monomer solution and the initiator solution are respectively introduced into the tubular reactor is 0.5-5 mol / L.

4. The preparation method according to claim 3, characterized in that: The molar ratio of the acrylic acid ester monomer to the initiator in the mixed solution system is 10 to 500:

1.

5. The preparation method according to claim 1 or 3, characterized in that: The acrylic acid ester monomer solution includes one or more of a methyl acrylate solution, an ethyl acrylate solution, a butyl acrylate solution, a methyl 2-methacrylate solution, and an ethyl 2-methacrylate solution.

6. The preparation method according to claim 1, characterized in that: The pumping speed ratio of the acrylic ester monomer solution to the initiator solution is 0.55-1.00:0.60-0.

80.

7. The preparation method according to claim 6, characterized in that: The acrylic acid ester monomer solution comprises methyl acrylate solution, ethyl acrylate solution and butyl acrylate solution, and the pumping speed ratio of the methyl acrylate solution, ethyl acrylate solution, butyl acrylate solution and initiator solution is 0.80-1.00: 0.70-0.90: 0.55-0.75: 0.60-0.

80.

8. The preparation method according to claim 1, characterized in that: The method further comprises circulating materials on the system obtained by the polymerization reaction, wherein the circulation ratio of the materials is 1:5 to 1:

30. 。 9. The preparation method according to claim 1, characterized in that: The front end of the tubular reactor is connected with a static mixer and an ultrasonic reactor in sequence. The output power of the ultrasonic reactor is 0.5-50 kW, and the output ultrasonic frequency is 10-100 kHz.

10. The acrylic acid ester solution polymer obtained by the preparation method according to any one of claims 1 to 9, characterized in that: The molecular weight distribution of the acrylic ester solution polymer is 1.20-1.30.

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