Polymerization catalyst composition and method for preparing block copolymer and use thereof

Abstract

This invention relates to the field of catalysts, and discloses a polymerization catalyst composition and a method for preparing block copolymers, as well as their applications. The polymerization catalyst composition contains a main catalyst and a co-catalyst, wherein the main catalyst is a compound represented by formula (I) and / or formula (II). The catalyst composition provided by this invention has the advantages of good catalytic activity and high stability. When the polymerization catalyst composition of this invention catalyzes the copolymerization of acrylate monomers and alkyl acrylate monomers, the resulting triblock acrylate copolymer exhibits relatively high stereoregularity of the alkyl acrylates and superior adhesion properties. The copolymer preparation process is simpler and more efficient.

Description

Technical Field

[0001] This invention relates to the field of catalysts, specifically to a catalyst composition for polymerization and its application in the preparation of block copolymers, a method for preparing block copolymers, and the application of block copolymers. Background Technology

[0002] Acrylic block copolymers are a class of polymeric materials that combine the properties of plastics and elastomers. Compared with traditional copolymers containing olefin units, acrylate copolymers have advantages such as weather resistance, oil resistance, heat oxidation resistance, and toughening. Moreover, the monomer types of acrylates are easy to control, allowing for the preparation of materials with different properties. Among them, triblock copolymers of methacrylate-acrylate-methacrylate are widely used in industrial production due to their excellent optical properties, weather resistance, and mechanical properties, especially in recent years in fields such as aerospace and automotive parts.

[0003] Currently, the main anionic synthesis methods for triblock acrylate copolymers include the coupling method and the monofunctional sequential feeding method. The coupling method first uses a monofunctional initiator to sequentially initiate the formation of an active diblock copolymer in two steps, and then uses a coupling agent to form a triblock copolymer. The sequential feeding method uses a monofunctional initiator to polymerize into a triblock copolymer through sequential feeding. However, the coupling method suffers from low coupling efficiency and a tendency to form diblock polymers, while the monofunctional sequential feeding method has problems such as multiple feeding steps and a wide molecular weight distribution.

[0004] Therefore, providing a new polymerization system with high synthesis efficiency and fewer reaction steps is of great significance for the production of triblock acrylate copolymers. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a polymerization catalyst composition that can efficiently catalyze block copolymerization reactions, as well as a method and application for preparing block copolymers.

[0006] To achieve the above objectives, a first aspect of the present invention provides a catalyst composition for polymerization, the composition comprising a main catalyst and a co-catalyst, wherein the main catalyst is a compound represented by formula (I) and / or formula (II).

[0007]

[0008] Wherein, R1, R2, R3, R4, R5, R6, R7, and R8 are each independently selected from at least one alkyl group of C1-20; R I R II R III R IVEach is independently selected from at least one of hydrogen and C1-C5 alkyl groups; m, n, p, o are each independently an integer from 0 to 4.

[0009] A second aspect of the present invention provides the use of the aforementioned polymerization catalyst composition in the preparation of block copolymers.

[0010] A third aspect of the present invention provides a method for preparing a block copolymer, the method comprising: copolymerizing a first monomer and a second monomer in the presence of a polymerization catalyst composition and a solvent, wherein the polymerization catalyst composition is the aforementioned polymerization catalyst composition.

[0011] The fourth aspect of the present invention provides the use of the block copolymer obtained by the aforementioned method as an optical protective film and / or an optical film adhesive.

[0012] The polymerization catalyst composition provided by this invention has the advantages of good catalytic activity and high stability. When the polymerization catalyst composition of this invention is applied to catalyze the copolymerization of acrylate monomers and alkyl acrylate monomers, the obtained triblock acrylate copolymer has a narrow molecular weight distribution, relatively high stereoregularity of alkyl acrylates, and better adhesion properties. The preparation method provided by this invention only requires two feeding steps to obtain triblock copolymers, making the process simpler and the preparation efficiency higher.

[0013] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0014] Figure 1 This is the GPC spectrum of the PMMA-n-BA-PMMA triblock acrylate copolymer obtained in Example 1;

[0015] Figure 2 It is the PMMA-n-BA-PMMA triblock acrylate copolymer prepared in Example 1. 1 H NMR spectrum;

[0016] Figure 3 It is the PMMA-n-BA-PMMA triblock acrylate copolymer prepared in Example 1. 13 C10 NMR spectrum. Detailed Implementation

[0017] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0018] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0019] In a first aspect, the present invention provides a catalyst composition for polymerization, the composition comprising a main catalyst and a co-catalyst, wherein the main catalyst is a compound represented by formula (I) and / or formula (II).

[0020]

[0021] Wherein, R1, R2, R3, R4, R5, R6, R7, and R8 are each independently selected from at least one alkyl group of C1-20; R I R II R III R IV Each is independently selected from at least one of hydrogen and C1-C5 alkyl groups; m, n, p, o are each independently an integer from 0 to 4.

[0022] "C1-20 alkyl" refers to alkyl groups containing a total of 1-20 carbon atoms, which can be straight-chain, branched, or cyclic alkyl groups; "C1-C5 alkyl" refers to alkyl groups containing a total of 1-5 carbon atoms, which can be straight-chain, branched, or cyclic alkyl groups.

[0023] The compounds with the structural formulas shown in Formula (I) and Formula (II) above are used as bifunctional initiators for polymerization reactions. They have good catalytic performance, can effectively improve the efficiency of polymerization reactions, and have high stability during the catalytic process. In particular, their catalytic performance is even better when applied to reactions in which two or more comonomers are polymerized to form block copolymers.

[0024] In this invention, the compounds with the structural formulas shown in formulas (I) and (II) above can be commercially available or synthesized using methods known in the prior art.

[0025] According to the present invention, preferably, R1, R2, R3, R4, R5, R6, R7, and R8 are each independently selected from at least one of C1-10 alkyl groups; more preferably, R1, R2, R3, R4, R5, R6, R7, and R8 are each independently selected from at least one of C1-4 alkyl groups; exemplaryly, R1, R2, R3, R4, R5, R6, R7, and R8 are each independently selected from at least one of methyl, ethyl, n-propyl, isopropyl, tert-butyl, sec-butyl, and tert-butyl.

[0026] According to the present invention, in a preferred embodiment, R I R II R III R IV Each is independently selected from at least one of hydrogen and C1-C3 alkyl groups, for example, R I R II R III R IV Each is independently selected from at least one of hydrogen, methyl, ethyl, n-propyl, and isopropyl.

[0027] According to the present invention, in a preferred embodiment, m, n, p, o are each independently 0, 1, or 2.

[0028] In each independent invention, R1 and R3 in the compound represented by formula (I) can be the same substituent or different substituents, preferably the same substituent; R2 and R4 can be the same substituent or different substituents, preferably the same substituent; R I and R III The substituents can be the same or different, but the same substituents are preferred; the R II and R IV The substituents can be the same or different, but are preferably the same; n and p can be the same or different integers, but are preferably the same; m and o can be the same or different integers, but are preferably the same; in formula (II), R5 and R7 can be the same or different, but are preferably the same; R6 and R8 can be the same or different, but are preferably the same.

[0029] According to the present invention, by way of example, the main catalyst may be:

[0030] At least one of the following; preferably, the main catalyst is a compound of formula (1), a compound of formula (2), a compound of formula (3) or a compound of formula (4), and more preferably a compound of formula (1).

[0031] According to the present invention, preferably, the co-catalyst is selected from at least one of inorganic lithium, lithium alkoxide and organoaluminum compounds.

[0032] According to the present invention, preferably, the inorganic lithium salt is selected from at least one of lithium chloride, lithium bromide, lithium sulfate and lithium nitrate, and more preferably lithium chloride.

[0033] According to the present invention, preferably, the lithium alkoxide is selected from at least one of lithium methoxide, lithium ethanol, lithium n-propoxide, lithium isopropoxide, lithium n-butoxide, lithium sec-butoxide, lithium tert-butoxide, lithium pentanol, lithium hexanool, lithium heptanol, lithium octanol, lithium phenoxy, lithium 4-methylphenoxy, lithium phenolate, lithium 4-methylphenolate, lithium benzyl alcohol, and lithium 4-methylbenzyl alcohol; more preferably, the lithium alkoxide is lithium tert-butoxide.

[0034] According to the present invention, the organoaluminum compound may be trimethylaluminum, triethylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-sec-butylaluminum, tri-tert-butylaluminum, methyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, ethyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, isobutyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, diethyl (2,6-di-tert-butylphenoxy)aluminum, or diisobutyl (2,6-di-tert-butylphenoxy) Aluminum, di-n-octyl(2,6-di-tert-butyl-4-methylphenoxy)aluminum, di-n-octyl(2,6-di-tert-butylphenoxy)aluminum, ethylbis(2,6-di-tert-butylphenoxy)aluminum, ethylbis[2,2′-methylenebis(4-methyl-6-tert-butylphenoxy)]aluminum, isobutylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, isobutylbis(2,6-di-tert-butylphenoxy)aluminum, isobutyl[(2,2′-methylenebis(4-methyl-6-tert-butylphenoxy)]aluminum, methoxybis(2,6-di-tert-butylphenoxy)aluminum, methoxy[2,2′-methylenebis(4-methyl-6-tert-butylphenoxy)]aluminum Aluminum, ethoxybis[(2,6-di-tert-butylphenoxy)]aluminum, ethoxy[2,2′-methylenebis(4-methyl-6-tert-butylphenoxy)]aluminum, isopropoxybis(2,6-di-tert-butylphenoxy)aluminum, isopropoxy[2,2′-methylenebis(4-methyl-6-tert-butylphenoxy)]aluminum, etc. Preferably, the organoaluminum compound is selected from at least one of methylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, ethylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, and isobutylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, more preferably isobutylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum.

[0035] According to the present invention, when the co-catalyst contains two or more components, the proportion of each component can be designed or adjusted according to the actual polymerization reaction requirements.

[0036] According to the present invention, in a more preferred embodiment, the co-catalyst is an inorganic lithium salt, such as lithium chloride. The inventors have found that, under this preferred embodiment, the catalyst composition of the present invention exhibits higher catalytic activity.

[0037] According to the present invention, preferably, the molar ratio of the main catalyst to the co-catalyst is 1:1-50, more preferably 1:5-20. The inventors have found that, under this preferred embodiment, the catalyst composition of the present invention has the advantage of improving catalytic activity and polymerization reaction efficiency.

[0038] Secondly, the present invention provides the application of the aforementioned polymerization catalyst composition in the preparation of block copolymers.

[0039] The polymerization catalyst composition provided by this invention is applied to the preparation of block copolymers via living anionic polymerization, effectively improving the efficiency of the polymerization reaction and simplifying the preparation process. For example, the monomers of the block copolymer can be one or more of alkyl acrylates, acrylates, alkyl acrylamides, acrylamides, alkyl acrylonitriles, acrylonitriles, and their derivatives. The corresponding block copolymers can be obtained by polymerization catalyzed by the aforementioned polymerization catalyst composition.

[0040] In this application of the present invention, there are no particular limitations on the order and method of adding the components in the catalyst composition for polymerization. The main catalyst and the co-catalyst can be mixed in advance and then added to the reaction system for preparing the block copolymer, or the main catalyst and the co-catalyst can be added to the reaction system for preparing the block copolymer separately.

[0041] Thirdly, the present invention provides a method for preparing block copolymers, the method comprising: copolymerizing a first monomer and a second monomer in the presence of a polymerization catalyst composition and a solvent, wherein the polymerization catalyst composition is the aforementioned polymerization catalyst composition.

[0042] In this invention, the first monomer and the second monomer can each be independently selected from alkyl acrylates, acrylates, alkyl acrylamides, acrylamides, alkyl acrylonitriles, acrylonitriles, and their derivatives. Preferably, the first monomer is an acrylate monomer and the second monomer is an alkyl acrylate monomer, or the first monomer is an acrylamide monomer and the second monomer is an alkyl acrylamide monomer, or the first monomer is an acrylonitrile monomer and the second monomer is an alkyl acrylonitrile monomer, so as to form corresponding triblock copolymers through copolymerization reactions.

[0043] More preferably, the first monomer is an acrylate monomer and the second monomer is an alkyl acrylate monomer. The inventors have found that, under this preferred embodiment, the aforementioned polymerization catalyst composition of the present invention, when applied to the preparation of triblock acrylate copolymers, not only exhibits high catalytic activity but also results in high stereoregularity and narrow molecular weight distribution of the methacrylates in the formed copolymer.

[0044] According to the present invention, preferably, the acrylate monomer is selected from at least one of the following: acrylates of straight-chain alcohols, acrylates of branched-chain alcohols, and acrylates of alicyclic alcohols. For example, it may be methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, tert-butyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, benzyl acrylate, dodecyl acrylate, or stearyl acrylate. More preferably, the acrylate monomer is n-butyl acrylate and / or tert-butyl acrylate.

[0045] According to the present invention, preferably, the alkyl acrylate monomer is selected from at least one of the following: methacrylates of straight-chain alcohols, methacrylates of branched-chain alcohols, and methacrylates of alicyclic alcohols. For example, it may be methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate, dodecyl methacrylate, or stearyl methacrylate. More preferably, the alkyl acrylate monomer is methyl methacrylate and / or tert-butyl methacrylate.

[0046] In this invention, the molar ratio of the first monomer to the second monomer can be set according to factors such as the molecular weight and molecular weight distribution of the triblock copolymer formed. For example, when the first monomer is an acrylate monomer and the second monomer is an alkyl acrylate monomer, the molar ratio of the acrylate monomer to the alkyl acrylate monomer is 1:0.01-100, preferably 1:0.1-10, and more preferably 1:0.4-2.5.

[0047] According to the present invention, the above preparation method, when using the composition of the present invention as a catalyst, can produce triblock acrylate copolymers with higher efficiency. Preferably, in the present invention, the molecular weight of the prepared triblock acrylate copolymer is 10,000-500,000 g / mol, and the molecular weight distribution is between 1.1 and 2.0.

[0048] In this invention, the method for preparing block copolymers is carried out in the presence of a solvent. The solvent can be any organic substance capable of serving as a reaction medium and enabling the reaction to proceed under solution polymerization conditions. Preferably, the solvent is an ether solvent to improve the stability of the aforementioned polymerization catalyst composition in the copolymerization reaction system, thereby increasing the copolymerization reaction temperature and reducing the energy consumption for solvent recovery. Preferably, the solvent is selected from at least one of tetrahydrofuran, tetrahydropyran, 1,4-dioxane, 2-methyltetrahydrofuran, and 2,5-dimethyltetrahydrofuran; these solvents can be used alone or in combination of two or more. More preferably, the solvent is tetrahydrofuran and / or 1,4-dioxane, and even more preferably tetrahydrofuran.

[0049] According to the present invention, the amount of solvent used is not particularly limited and can be a conventional amount used in the art. Preferably, the ratio between the total volume of the first monomer and the second monomer and the volume of the solvent is 1:1-20, more preferably 1:5-10.

[0050] According to the present invention, preferably, the ratio of the total molar amount of the first monomer and the second monomer to the molar amount of the main catalyst is 100-5000:1, more preferably 200-5000:1, and even more preferably 500-4000:1. Particularly preferably, the ratio of the total molar amount of the first monomer and the second monomer to the molar amount of the main catalyst is 800-2400:1. The inventors have found that, under this preferred embodiment, the aforementioned catalyst composition for polymerization of the present invention exhibits superior catalytic activity, higher efficiency in preparing triblock acrylate copolymers, and superior adhesive properties of the obtained triblock acrylate copolymers.

[0051] According to the present invention, preferably, the copolymerization reaction is carried out under an inert atmosphere, such as one or more of nitrogen, helium, argon, etc.

[0052] According to the present invention, in the copolymerization reaction, a terminator can be used to terminate the copolymerization reaction after the reaction is completed. The terminator used for this step is conventional to those skilled in the art. Commonly used terminators include deionized water, alcohols, acids, etc. In the present invention, the preferred terminator is one or more selected from isopropanol, methanol, ethanol, and water.

[0053] According to the present invention, preferably, the conditions for the copolymerization reaction include: a temperature of -60°C to 20°C, more preferably -40°C to 20°C; and a time of 10 min to 24 h, more preferably 60 min to 12 h. More preferably, the copolymerization reaction time is 2 h to 4 h.

[0054] According to the present invention, in the reaction system for preparing block copolymers, there are no particular limitations on the order and method of adding the first monomer and the second monomer. To control the block structure of the formed triblock copolymer, preferably, the copolymerization process includes: in the presence of a polymerization catalyst composition and a solvent, first adding one of the first monomer and the second monomer to carry out a first-stage reaction, and then adding the other to carry out a second-stage reaction. By using a two-step feeding method, the first monomer and the second monomer are added separately to the copolymerization system to obtain copolymers with different block structures.

[0055] For example, let A represent the first monomer and B represent the second monomer. First, add the first monomer A to the copolymerization system to carry out the first stage reaction, and then add the second monomer B to carry out the second stage reaction to prepare a triblock copolymer with a BAB structure. Second, add the second monomer B to the copolymerization system to carry out the first stage reaction, and then add the first monomer A to carry out the second stage reaction to prepare a triblock copolymer with an ABA structure.

[0056] According to the present invention, the temperatures of the first stage reaction and the second stage reaction can be the same or different, preferably the temperatures of the first stage reaction and the second stage reaction are the same, that is, the copolymerization process is an isothermal reaction. The time of the first stage reaction is set according to the total reaction time of the copolymerization reaction, preferably, the time of the first stage reaction is 5 min to 3 h.

[0057] Fourthly, the present invention provides the application of the block copolymers obtained by the aforementioned method as optical protective films and / or optical film adhesives.

[0058] According to a particularly preferred embodiment of the present invention, a method for preparing a triblock acrylate copolymer is provided, comprising the following steps:

[0059] In the presence of a polymerization catalyst composition and solvent, and at a temperature ranging from -60°C to 20°C, acrylate monomer A is first added to the copolymerization system for the first stage reaction, followed by the addition of alkyl acrylate monomer B for the second stage reaction, to prepare a triblock acrylate copolymer with a BAB structure; or,

[0060] In the presence of a polymerization catalyst composition and a solvent, under conditions of -60°C to 20°C and inert gas protection, alkyl acrylate monomer B is first added to the copolymerization system for the first stage reaction, and then acrylate monomer A is added for the second stage reaction to prepare a triblock acrylate copolymer with an ABA structure.

[0061] The polymerization catalyst composition contains a main catalyst and a co-catalyst, wherein the main catalyst is selected from... One of the catalysts is selected from at least one of inorganic lithium salts, lithium alkoxides, and organoaluminum compounds; the solvent is tetrahydrofuran and / or 1,4-dioxane; the molar ratio of the main catalyst to the catalyst is 1:1-50; the molar ratio of acrylate monomers to alkyl acrylate monomers is 1:0.01-100; the ratio between the total molar amount of acrylate monomers and alkyl acrylate monomers and the molar amount of the main catalyst is 100-5000:1; and the ratio between the total volume of acrylate monomers and alkyl acrylate monomers and the volume of the solvent is 1:1-20.

[0062] The present invention will be described in detail below with reference to embodiments, but this does not limit the scope of the invention.

[0063] In the following examples and comparative examples, the number-average molecular weight M is... n The molecular weight distribution index (PDI) was determined using gel permeation chromatography (GPC) at 40°C with THF as the mobile phase.

[0064] In the following examples and comparative examples, the microstructure of the block copolymers was determined using an AVANCE-III 400 MHz NMR spectrometer from Bruker GmbH, Germany, with deuterated chloroform (CDCl3) as the solvent and tetramethylsilane (TMS) as the internal standard, at 298 K. 1 In the H-NMR spectrum, signals near 3.6 ppm and 4.0 ppm are attributed to ester groups of the methyl methacrylate unit and the n-butyl acrylate unit, respectively. The content of the copolymer component is determined by the ratio of their integral values. 13 In the C-NMR spectrum, the signals near 44.5 ppm, 44.8 ppm, and 45.5 ppm are attributed to the quaternary carbons of the polymethyl methacrylate block, corresponding to stereotypes rr, mr, and mm, respectively. Stereotype rr is obtained by the ratio of their integral values.

[0065] In the following examples and comparative examples, the energy storage modulus (23°C, 90°C) of the block copolymers was tested using the following methods:

[0066] (1) After dissolving the block copolymer prepared in the following examples or comparative examples in toluene to prepare a block copolymer solution with a solid component concentration of 30 wt%, the solution was injected into a box made of release paper (polyethylene terephthalate film substrate); then, after air drying at room temperature for 24 h, it was vacuum dried at 60 °C for 24 h to produce a sheet with a block copolymer layer thickness of about 1 mm. The sheet was punched into a circle with a diameter of 8 mm, and the substrate was peeled off to produce a test piece, thus obtaining an adhesive optical film containing release polyethylene terephthalate film / block polymer / polyethylene terephthalate film substrate;

[0067] (2) Using the test piece manufactured in (1) above, the dynamic viscoelastic temperature dispersion was determined using the following apparatus and conditions. The values ​​of the energy storage modulus (G') at 23°C and 90°C were respectively denoted as “G'(23°C)” and “G'(90°C)”.

[0068] - Device: "Advanced Rheometric Expansion System" manufactured by Rhemetric Scientific

[0069] - Parallel plate: 8mm in diameter

[0070] - Frequency: 6.28 rad / s

[0071] -Measurement temperature range: -50℃ to 250℃

[0072] - Heating rate: 3℃ / min

[0073] - Deformation: 0.05% (-50℃ to -37℃), 10% (-37℃ to -15℃), 5.0% (-15℃ to 250℃).

[0074] The solution viscosity of the block copolymer was tested using the following method:

[0075] The block copolymers prepared in the following examples or comparative examples were dissolved in toluene to prepare a block copolymer solution with a solid content concentration of 45 wt%. The viscosity of the block copolymer solution at 25°C was measured using a Brookfield viscometer.

[0076] The adhesive strength and residual properties of block copolymers:

[0077] (1) After dissolving the block copolymer prepared in the following examples or comparative examples in toluene to prepare a block copolymer solution with a solid component concentration of 30 wt%, the solution was injected into a box made of release paper (polyethylene terephthalate film substrate); then, after air drying at room temperature for 24 h, it was vacuum dried at 60 °C for 24 h to produce a sheet with a block copolymer layer thickness of about 1 mm. The sheet was punched into a circle with a diameter of 8 mm, and the substrate was peeled off to make an adhesive optical film. The film was then cut into dimensions of width × length = 25 mm × 200 mm as a test piece.

[0078] (2) Adhesive strength and block copolymer residue in the initial bonding stage (without heat treatment):

[0079] (a) Peel off the release PET film from one surface of the test piece manufactured in (1) above, and stick it to a glass plate or polycarbonate plate as the substrate. Use a 2kg roller to reciprocate twice on the adhesive optical film at a speed of 10mm / s to perform the bonding. After being placed at a temperature of 23°C, a humidity of 50%RH and an atmospheric pressure for 24 hours, the 180° peel adhesion force is then measured according to JIS Z0237 at a peel speed of 300mm / min.

[0080] (b) Visually observe whether there are any block copolymer residues on the glass plate or polycarbonate plate after the 180° peel adhesion test in (a) above. If there are any block copolymer residues, the condition is evaluated as "block copolymer residues exist". If there are no block copolymer residues and the peeling is smooth, the condition is evaluated as "no block copolymer residues exist".

[0081] (3) Adhesion strength and block copolymer residue after heat treatment:

[0082] (a) Peel off the release PET film from one surface of the test piece manufactured in (1) above, and stick it to a glass plate or polycarbonate plate as the substrate. Use a 2kg roller to reciprocate twice on the adhesive optical film at a speed of 10mm / s to perform the bonding. After heat treatment in a hot air oven at 70°C for 15h, place it in an atmospheric pressure at 23°C and 50%RH for 1h to adjust the humidity. According to JIS Z0237, the 180° peel adhesion force is measured at a peel speed of 300mm / min.

[0083] (b) Visually observe whether there are any block copolymer residues on the glass plate or polycarbonate plate after the 180° peel adhesion test in (a) above. If there are any block copolymer residues, the condition is evaluated as "block copolymer residues exist". If there are no block copolymer residues and the peeling is smooth, the condition is evaluated as "no block copolymer residues exist".

[0084] (4) Adhesion strength and block copolymer residue after autoclave treatment:

[0085] (a) Peel off the release PET film from one surface of the test piece manufactured in (1) above and stick it to a glass plate or polycarbonate plate as the substrate. Use a 2 kg roller to reciprocate twice on the adhesive optical film at a speed of 10 mm / s. After autoclaving at 50°C and 5 atmospheres (0.5 MPa) for 15 min, further humidify by placing it at 23°C and 50% RH for 1 hour. According to JIS Z0237, the 180° peel adhesion is measured at a peeling speed of 300 mm / min.

[0086] (b) Visually observe whether there are any block copolymer residues on the glass plate or polycarbonate plate after the 180° peel adhesion test in (a) above. If there are any block copolymer residues, the condition is evaluated as "block copolymer residues exist". If there are no block copolymer residues and the peeling is smooth, the condition is evaluated as "no block copolymer residues exist".

[0087] (5) Adhesion and block copolymer residue after autoclave treatment and heat treatment:

[0088] (a) Peel off the release PET film from one surface of the test piece manufactured in (1) above and stick it to a glass plate or polycarbonate plate as the substrate. Use a 2kg roller to reciprocate twice on the adhesive optical film at a speed of 10mm / s. After autoclaving at 50°C and 5 atmospheres (0.5MPa) for 15 minutes, heat treat it in a hot air oven at 70°C for 15 hours. Then, humidify it by placing it at 23°C and 50%RH for 1 hour. According to JIS Z0237, the 180° peel adhesion force is measured at a peeling speed of 300mm / min.

[0089] (b) Visually observe whether there are any block copolymer residues on the glass plate or polycarbonate plate after the 180° peel adhesion test in (a) above. If there are any block copolymer residues, the condition is evaluated as "block copolymer residues exist". If there are no block copolymer residues and the peel is successful, the condition is evaluated as "no block copolymer residues exist".

[0090] Block copolymer retention force test (creep test):

[0091] After dissolving the block copolymers prepared in the following examples or comparative examples in toluene to prepare a block copolymer solution with a solid content concentration of 30 wt%, the solution was injected into a box made of release paper (polyethylene terephthalate film substrate); then, after air drying at room temperature for 24 h, it was vacuum dried at 60 °C for 24 h to produce a sheet with a block copolymer layer thickness of about 1 mm. The sheet was punched into a circle with a diameter of 8 mm, and the substrate was peeled off to make an adhesive optical film. The film was then cut into dimensions of width × length = 25 mm × 40 mm as a test piece.

[0092] For the portion of the test piece still bearing the weight, peel off the release PET film from one surface and attach it to a glass plate or polycarbonate plate as the substrate, with a width of 25 mm (perpendicular to the load orientation) and a length of 10 mm (same as the load orientation). Install a 1 kg weight on the test piece. At 90°C, according to JIS Z0237, measure the positional deviation of the test piece after 30 min, 60 min, or 1000 min, while simultaneously peeling the test piece from the glass plate or polycarbonate plate and measuring the time it takes for the weight to fall. Then, score the durability (adhesion holding power) of the block copolymer according to the evaluation criteria shown in Table 1 below.

[0093] This test is used to investigate the durability of block copolymers. There is no deviation in the position of the test piece. In addition, the longer the time before the test piece falls off, the better the durability of the block copolymer.

[0094] Table 1 Evaluation Criteria for Creep Test

[0095]

[0096] The shear-bonded failure temperature (SAFT) of block copolymers is determined according to ASTM D4498. This test is used to investigate the durability and heat resistance of block copolymers. The higher the temperature at which the weight falls off, the better the durability and heat resistance of the block copolymer, indicating that it is suitable for use under high temperature conditions.

[0097] In the following examples and comparative examples, the transmittance of the block copolymers was tested in accordance with GB / T 2410-2008 Determination of transmittance and haze of transparent plastics.

[0098] In the following examples and comparative examples, the compounds shown in formula (1), formula (2), formula (3), formula (4), formula (5), and formula (9) were all custom-made by Qingdao Prier Biotechnology Co., Ltd.; other raw materials and reagents were all commercially available products.

[0099] Example 1

[0100] In a 250 mL reaction flask, under an argon atmosphere, 60 mL of anhydrous and oxygen-free tetrahydrofuran, 0.10 mmol of the compound shown in formula (1), and 0.50 mmol of co-catalyst LiCl were added sequentially. The reaction system was then cooled to -40 °C. At a temperature of -40 °C, 60.0 mmol of n-butyl acrylate (n-BA) was slowly added dropwise to the reaction system to control the system temperature to not exceed -38 °C. The reaction was kept at a constant temperature for 1 h. Then, 30.0 mmol of methyl methacrylate (MMA) was slowly added dropwise to the reaction system, and the reaction was continued for 1 h. After the reaction was completed, the mixture was quenched with a large amount of cold methanol, and the solid was precipitated and dried under vacuum at 40 °C for 24 h to obtain PMMA-PnBA-PMMA triblock acrylate copolymer. The calculated yield was >99%.

[0101]

[0102] The gel permeation chromatography (GPC) chromatogram of the PMMA-PnBA-PMMA triblock acrylate copolymer prepared in Example 1 is shown below. Figure 1 As shown, nuclear magnetic resonance (NMR) analysis yielded... 1 H NMR spectrum as shown Figure 2 As shown, the contents of methacrylate blocks and acrylate blocks in the block copolymer were obtained. 13 The C NMR spectrum is as follows Figure 3 As shown, the stereoregularity of methacrylate in the copolymer was obtained. The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0103] Example 2

[0104] The method of Example 1 was followed, except that the main catalyst was replaced by the compound shown in Formula (1) with the compound shown in Formula (2) to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%;

[0105]

[0106] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0107] Example 3

[0108] The method of Example 1 was followed, except that the main catalyst was replaced by the compound shown in Formula (1) with the compound shown in Formula (3) to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%;

[0109]

[0110] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0111] Example 4

[0112] Prepared according to the method of Example 1, except that the main catalyst was replaced by the compound shown in Formula (1) with the compound shown in Formula (4) to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%;

[0113]

[0114] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0115] Example 5

[0116] In a 250 mL reaction flask, under an argon atmosphere, 60 mL of anhydrous and oxygen-free tetrahydrofuran, 0.10 mmol of the compound shown in formula (1), and 2 mmol of co-catalyst LiCl were added sequentially. The reaction system was then cooled to 0 °C. At 0 °C, 60.0 mmol of n-butyl acrylate (n-BA) was slowly added dropwise to the reaction system to control the system temperature to not exceed 1 °C. The reaction was carried out at a constant temperature for 1 h. Then, 30.0 mmol of methyl methacrylate (MMA) was slowly added dropwise to the reaction system, and the reaction was continued for another 1 h. After the reaction was completed, the mixture was quenched with a large amount of cold methanol, and the solid was precipitated and dried under vacuum at 40 °C for 24 h to obtain PMMA-PnBA-PMMA triblock acrylate copolymer. The calculated yield was >99%.

[0117] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0118] Example 6

[0119] Prepared according to the method of Example 1, except that 60.0 mmol of n-butyl acrylate was replaced with 60.0 mmol of 2-ethylhexyl acrylate (2-EHAA) to obtain PMMA-P2-EHAA-PMMA triblock acrylate copolymer, with a calculated yield of >99%.

[0120] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0121] Example 7

[0122] In a 250 mL reaction flask, under an argon atmosphere, 60 mL of anhydrous and oxygen-free tetrahydrofuran, 0.10 mmol of the compound shown in formula (1), and 1 mmol of co-catalyst isobutyl di(2,6-di-tert-butyl-4-methylphenoxy)aluminum were added sequentially. The reaction system was then cooled to -40 °C. At a temperature of -40 °C, 60.0 mmol of n-butyl acrylate (n-BA) was slowly added dropwise to the reaction system to control the system temperature to not exceed -39 °C. The reaction was carried out at a constant temperature for 1 h. Then, 40.0 mmol of methyl methacrylate (MMA) was slowly added dropwise to the reaction system, and the reaction was continued for another 1 h. After the reaction was completed, the mixture was quenched with a large amount of cold methanol, and the solid was precipitated and dried under vacuum at 40 °C for 24 h to obtain PMMA-PnBA-PMMA triblock acrylate copolymer. The calculated yield was >99%.

[0123] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0124] Example 8

[0125] In a 250 mL reaction flask, under an argon atmosphere, 60 mL of anhydrous and oxygen-free tetrahydrofuran, 0.10 mmol of the compound shown in formula (1), and 0.50 mmol of co-catalyst LiCl were added sequentially. The reaction system was then cooled to -40 °C. At a temperature of -40 °C, 60.0 mmol of methyl methacrylate (MMA) was slowly added dropwise to the reaction system to control the system temperature to not exceed -39 °C. The reaction was carried out at a constant temperature for 1 h. Then, 40.0 mmol of n-butyl acrylate (n-BA) was slowly added dropwise to the reaction system, and the reaction was continued for another 1 h. After the reaction was completed, the mixture was quenched with a large amount of cold methanol, and the solid was precipitated and dried under vacuum at 40 °C for 24 h to obtain PnBA-PMMA-PnBA triblock acrylate copolymer. The calculated yield was >99%.

[0126] The molecular weight and microstructure data of the product are shown in Table 2.

[0127] Example 9

[0128] In a 500 mL reaction flask, under an argon atmosphere, 120 mL of anhydrous and oxygen-free tetrahydrofuran, 0.10 mmol of the compound shown in formula (1), and 0.50 mmol of co-catalyst LiCl were added sequentially. The reaction system was then cooled to -40 °C. At a temperature of -40 °C, 120.0 mmol of n-butyl acrylate (n-BA) was slowly added dropwise to the reaction system to control the system temperature to not exceed -39 °C. The reaction was carried out at a constant temperature for 1 h. Then, 80.0 mmol of methyl methacrylate (MMA) was slowly added dropwise to the reaction system, and the reaction was continued for 1 h. After the reaction was completed, the mixture was quenched with a large amount of cold methanol, and the solid was precipitated and dried under vacuum at 40 °C for 24 h to obtain PMMA-PnBA-PMMA triblock acrylate copolymer. The calculated yield was >99%.

[0129] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0130] Example 10

[0131] The method of Example 1 was followed, except that 60 mL of anhydrous and oxygen-free tetrahydrofuran was replaced with 60 mL of anhydrous and oxygen-free 1,4-dioxane to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%.

[0132] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0133] Example 11

[0134] The method of Example 1 was followed, except that the main catalyst was replaced by the compound shown in Formula (1) with the compound shown in Formula (5) to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%;

[0135]

[0136] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0137] Example 12

[0138] Prepared according to the method of Example 1, except that the main catalyst was replaced by 0.10 mmol of the compound shown in formula (1) with 0.05 mmol of the compound shown in formula (1) and 0.05 mmol of the compound shown in formula (2), to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%.

[0139] The molecular weight and microstructure data of the product are shown in Table 2.

[0140] Example 13

[0141] The method of Example 1 was followed, except that 0.10 mmol of the compound shown in Formula (1) was replaced with 0.20 mmol of the compound shown in Formula (1), and 0.50 mmol of cocatalyst LiCl was replaced with 0.20 mmol of cocatalyst LiCl, to obtain PMMA-PnBA-PMMA triblock acrylate copolymer with a calculated yield of >99%.

[0142] The molecular weight and microstructure data of the product are shown in Table 2.

[0143] Example 14

[0144] The method of Example 1 was followed, except that 60.0 mmol n-butyl acrylate (n-BA) was replaced with 20.0 mmol n-butyl acrylate (n-BA), and 30.0 mmol methyl methacrylate (MMA) was replaced with 10.0 mmol methyl methacrylate (MMA) to obtain PMMA-PnBA-PMMA triblock acrylate copolymer with a calculated yield of >99%.

[0145] The molecular weight and microstructure data of the product are shown in Table 2.

[0146] Example 15

[0147] The PMMA-Pn-BA-PMMA triblock acrylate copolymer was prepared according to the method in Example 1, except that 60.0 mmol of n-butyl acrylate (n-BA) and 30.0 mmol of methyl methacrylate (MMA) were simultaneously and slowly added dropwise to the reaction system, and the reaction was carried out at a constant temperature for 2 h to obtain the PMMA-Pn-BA-PMMA triblock acrylate copolymer with a calculated yield of >99%.

[0148] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0149] Comparative Example 1

[0150] Prepared according to the method of Example 1, except that the main catalyst was replaced by the compound shown in formula (1) with naphthalene lithium; PMMA-PnBA-PMMA triblock acrylate copolymer could not be obtained after the reaction.

[0151] Comparative Example 2

[0152] The method of Example 1 was followed, except that the main catalyst was replaced by the compound shown in Formula (1) with the compound shown in Formula (9) to obtain PMMA-PnBA-PMMA triblock acrylate copolymer, with a calculated yield of >99%;

[0153]

[0154] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0155] Comparative Example 3

[0156] The method of Example 1 was followed, except that the main catalyst was replaced by 1,4-dimethyl-1,4-diphenylbutanedilithium to obtain PMMA-PnBA-PMMA triblock acrylate copolymer with a calculated yield of 81%.

[0157] The molecular weight and microstructure data of the product are shown in Table 2, and the mucosal properties and light transmittance data are shown in Table 3.

[0158] Comparative Example 4

[0159] Prepared according to the method of Example 1, except that the main catalyst was replaced by n-butyllithium instead of the compound shown in Formula (1); PMMA-PnBA-PMMA triblock acrylate copolymer could not be obtained after the reaction.

[0160] Comparative Example 5

[0161] The method of Example 1 was followed, except that 0.50 mmol of co-catalyst LiCl was not added; PMMA-PnBA-PMMA triblock acrylate copolymer could not be obtained after the reaction.

[0162] Table 2

[0163]

[0164]

[0165] Table 3

[0166]

[0167]

[0168] As can be seen from the results in Tables 2 and 3, the catalyst provided by this invention exhibits high catalytic activity in the copolymerization reaction of acrylates and alkyl acrylates, and the triblock acrylate copolymer obtained has relatively high stereoregularity of methacrylate. When used as an adhesive, it has superior adhesive properties such as energy storage modulus, adhesive force, and SAFT test temperature. The triblock acrylate copolymer obtained by this invention has a light transmittance of >99%, making it suitable for use as an optical protective film.

[0169] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A catalyst composition for polymerization, characterized in that, The composition contains a main catalyst and a co-catalyst, wherein the main catalyst is a compound represented by formula (II). Equation (II), R5, R6, R7, and R8 are each independently selected from C1-20 alkyl groups; The molar ratio of the main catalyst to the co-catalyst is 1:1-50.

2. The composition according to claim 1, characterized in that, In formula (II), R5 and R7 are the same substituents, and R6 and R8 are the same substituents; and / or, The molar ratio of the main catalyst to the co-catalyst is 1:5-20.

3. The composition according to claim 1, characterized in that, The main catalyst is or .

4. The composition according to any one of claims 1-3, characterized in that, The co-catalyst is selected from at least one of inorganic lithium salts, lithium alkoxides, and organoaluminum compounds.

5. The composition according to claim 4, characterized in that, The inorganic lithium salt is selected from at least one of lithium chloride, lithium bromide, lithium sulfate, and lithium nitrate; and / or, The lithium alkoxide is selected from at least one of lithium methoxide, lithium ethanol, lithium n-propoxide, lithium isopropoxide, lithium n-butoxide, lithium sec-butoxide, lithium tert-butoxide, lithium pentanol, lithium hexanool, lithium heptanol, lithium octanol, lithium phenoxy, lithium 4-methylphenoxy, lithium phenolate, lithium 4-methylphenolate, lithium benzyl alcohol, and lithium 4-methylbenzyl alcohol; and / or, The organoaluminum compound is selected from at least one of methyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, ethyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum, and isobutyl bis(2,6-di-tert-butyl-4-methylphenoxy)aluminum.

6. The composition according to claim 5, characterized in that, The inorganic lithium salt is lithium chloride; and / or, The lithium alkoxide is lithium tert-butoxide; and / or... The organoaluminum compound is isobutylbis(2,6-di-tert-butyl-4-methylphenoxy)aluminum.

7. The use of the polymerization catalyst composition according to any one of claims 1 to 6 in the preparation of block copolymers.

8. A method for preparing block copolymers, characterized in that, The method includes: copolymerizing a first monomer and a second monomer in the presence of a polymerization catalyst composition and a solvent, wherein the polymerization catalyst composition is the polymerization catalyst composition according to any one of claims 1 to 6.

9. The method according to claim 8, characterized in that, The first monomer is an acrylate monomer, and the second monomer is an alkyl acrylate monomer.

10. The method according to claim 9, characterized in that, The acrylate monomer is selected from at least one of the following: acrylates of straight-chain alcohols, acrylates of branched-chain alcohols, and acrylates of alicyclic alcohols; and / or, The alkyl acrylate monomer is selected from at least one of the following: methacrylates of straight-chain alcohols, methacrylates of branched-chain alcohols, and methacrylates of alicyclic alcohols.

11. The method according to claim 10, characterized in that, The acrylate monomer is n-butyl acrylate and / or tert-butyl acrylate; and / or... The alkyl acrylate monomer is methyl methacrylate and / or tert-butyl methacrylate.

12. The method according to claim 8 or 9, characterized in that, The solvent is selected from at least one of tetrahydrofuran, tetrahydropyran, 1,4-dioxane, 2-methyltetrahydrofuran, and 2,5-dimethyltetrahydrofuran.

13. The method according to claim 12, characterized in that, The solvent is tetrahydrofuran and / or 1,4-dioxane.

14. The method according to claim 8 or 9, characterized in that, The ratio between the total molar amount of the first monomer and the second monomer and the molar amount of the main catalyst is 100-5000:1; and / or, The ratio between the total volume of the first monomer and the second monomer and the volume of the solvent is 1:1-20.

15. The method according to claim 14, characterized in that, The ratio between the total molar amount of the first monomer and the second monomer and the molar amount of the main catalyst is 200-5000:1; and / or, The ratio between the total volume of the first monomer and the second monomer and the volume of the solvent is 1:5-10.

16. The method according to claim 15, characterized in that, The ratio between the total molar amount of the first monomer and the second monomer and the molar amount of the main catalyst is 500-4000:

1.

17. The method according to claim 8 or 9, characterized in that, The conditions for the copolymerization reaction include: a temperature of -60°C to 20°C, and a time of 10 min to 24 h; and / or, The copolymerization process includes: in the presence of a polymerization catalyst composition and a solvent, first adding one of the first monomer and the second monomer to carry out a first-stage reaction, and then adding the other monomer to carry out a second-stage reaction.

18. The method according to claim 17, characterized in that, The conditions for the copolymerization reaction include: a temperature of -40°C to 20°C; a time of 60 min to 12 h; and / or, The reaction time for the first stage is 5 min to 3 h.

19. The method according to claim 18, characterized in that, The copolymerization reaction takes 2-4 hours.

20. The use of the block copolymer prepared by the method according to any one of claims 8 to 19 as an optical protective film and / or optical film adhesive.

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