Use of a lewis acid-base pair in catalysing the polymerization of functionalisable monomers

Abstract

The application belongs to the technical field of catalytic synthesis, and particularly relates to application of a Lewis acid-base pair in catalyzing polymerization of functionalizable monomers. Common polymerization methods have poor controllability for polymerization of monomers containing polyene groups, alkyne groups and conjugated diene groups, and the molecular weight of the obtained polymer is uncontrollable at low monomer conversion, and the molecular weight distribution is wide, and crosslinking occurs at high monomer conversion. The application utilizes a specific Lewis acid-base pair, and by adjusting the electronic effect and steric hindering effect of the Lewis acid and the Lewis base, active controllable polymerization of the functionalizable monomers can be catalyzed, and a polymer with a clear structure and containing functionalizable sites is obtained, the molecular weight is controllable, the molecular weight distribution is narrow, the end group structure is controllable, the position and density of the functionalizable sites are conveniently adjusted, an efficient platform is provided for post-modification preparation of functional high molecular materials, and functional high molecular materials are prepared by combining click reaction.

Description

Technical Field

[0001] This invention belongs to the field of catalytic synthesis technology, specifically relating to the application of a Lewis acid-base pair in the catalytic polymerization of functionalizable monomers. Background Technology

[0002] Functional polymer materials are widely used in various fields due to their specific physical and chemical properties, such as photosensitive polymers, conductive polymers, photoelectric conversion polymers, medical polymers, and polymer catalysts. However, the synthesis of functional polymer materials is relatively difficult, and there are two main methods. One method is to prepare functional polymer materials by polymerizing monomers with specific groups.

[0003] Another approach involves first obtaining a functionalizable polymer precursor through polymerization, and then transforming the functionalizable sites through certain chemical reactions to introduce specific groups, thereby preparing functional polymer materials. However, this method currently cannot guarantee that the polymer precursor contains the target functionalizable sites. Summary of the Invention

[0004] The purpose of this invention is to provide an application of Lewis acid-base pairs in the catalytic polymerization of functionalizable monomers. This invention uses specific Lewis acid-base pairs to catalyze the active and controllable polymerization of functionalizable monomers, resulting in polymers with well-defined structures containing functionalizable sites.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides an application of Lewis acid-base pairs in the catalytic polymerization of functionalizable monomers, wherein the Lewis acid-base pair comprises a Lewis acid and a Lewis base; and the Lewis base comprises one or more of the following: a Lewis base of formula NHO, a Lewis base of formula IAP, a Lewis base of formula DIAP, and a Lewis base of formula PyAP.

[0007] ;

[0008] In formulas NHO, IAP, DIAP, and PyAP, n = 1 to 9, R1 is hydrogen, alkyl, or phenyl; R2 is hydrogen, alkyl, phenyl, or substituted phenyl; R3 is alkyl, phenyl, or substituted phenyl; R4 is alkyl, phenyl, or substituted phenyl; R5 is hydrogen, alkyl, phenyl, or substituted phenyl; and R6 is hydrogen, alkyl, phenyl, or substituted phenyl.

[0009] Preferably, the application includes the following steps: mixing monomers, Lewis acid-base pairs, and organic solvents to carry out a polymerization reaction to obtain a polymer.

[0010] Preferably, the molar ratio of the monomer to the Lewis base in the Lewis acid-base pair is 15~50000:1.

[0011] Preferably, the concentration of the monomer in the mixed solution is not less than 0.2 M.

[0012] Preferably, the polymerization reaction temperature is -50~100 ℃, and the reaction time is 10 s~72 h.

[0013] Preferably, the monomer includes one or more of butyl methacrylate, propargyl methacrylate, and methacrylate.

[0014] Preferably, the organic solvent includes one or more of benzene homologues, furans, amides, and substituted benzenes.

[0015] Preferably, the mixing of the monomer, Lewis acid-base pair, and organic solvent is performed as follows: the monomer is mixed with a first portion of the organic solvent to obtain a monomer solution; the Lewis acid is mixed with a second portion of the organic solvent to obtain a Lewis acid solution; the Lewis base is mixed with a third portion of the organic solvent to obtain a Lewis base solution; the monomer solution, the Lewis acid solution, and the remaining portion of the organic solvent are mixed to obtain a premix; and then the premix and the Lewis base solution are mixed.

[0016] Preferably, the molar ratio of the Lewis acid to the Lewis base is not less than 2:1.

[0017] Preferably, the Lewis acid includes one or more of the following: Lewis acid of formula A-1, Lewis acid of formula A-2, Lewis acid of formula A-3, and Lewis acid of formula A-4;

[0018]

[0019] Formula A-1; Formula A-2; Formula A-3; Formula A-4;

[0020] In formulas A-1 to A-4, R1 is an alkyl or halogen; R2 is hydrogen, alkyl, substituted alkyl, or halogen; and R3 is hydrogen, alkyl, or halogen.

[0021] This invention provides an application of Lewis acid-base pairs in the catalytic polymerization of functionalizable monomers. Due to the poisoning effect of functional groups such as alkenyl, alkynyl, and conjugated dienyl groups on catalysts, or the occurrence of various side reactions by these functional groups during polymerization, commonly used catalysts have poor control over the polymerization of monomers containing polyalkenyl, alkynyl, and conjugated dienyl groups. Various side reactions may occur during the polymerization reaction (including coordination of alkenyl or alkynyl groups on the catalyst, chain transfer or cross-linking caused by free radicals generated on alkenyl or alkynyl groups, etc.). Strict control of reaction conditions or timely quenching of the polymerization reaction is required to avoid cross-linking. Furthermore, the resulting polymer has an uncontrollable molecular weight distribution and exhibits cross-linking at high monomer conversion rates. This invention utilizes specific Lewis acid-base pairs. By adjusting the electronic and steric hindrance effects of Lewis acids and bases, it can catalyze the active and controllable polymerization of functionalizable monomers, yielding polymers with well-defined structures containing functionalizable sites. These polymers have controllable molecular weights, narrow molecular weight distributions, and controllable end-group structures. The positions and densities of functionalizable sites (such as alkynyl, alkenyl, and conjugated dienyl groups) can be easily adjusted, overcoming the difficulty in synthesizing functionalizable polymers with precise structures. Furthermore, it introduces highly reactive functionalizable sites, overcoming the problem that large polymer steric hindrance makes it difficult to quickly and completely convert functionalizable sites into specific groups. This provides an efficient platform for post-modification preparation of functional polymer materials. Combined with click reactions, functional polymer materials can be prepared. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 GPC curves of polymers prepared in Examples 3 and 7-13 with different [AMA]0 / [IAP-1]0 ratios;

[0024] Figure 2 The graph shows the relationship between monomer conversion rate and the molecular weight and molecular weight distribution of the prepared polymer.

[0025] Figure 3 For IAP-1 / i MALDI TOF spectrum of low molecular weight PAMA produced by Bu2Al(BHT) catalytic polymerization of AMA;

[0026] Figure 4 For IAP-1 / i Superimposed GPC curves of Bu2Al(BHT) catalyzed AMA chain extension (a) and IAP-1 / iSuperimposed GPC curves of Bu2Al(BHT) catalyzed MMA and AMA block copolymerization (b);

[0027] Figure 5 The 1H NMR spectrum of the alkenyl polymer after the click reaction of the thiol-olefin addition reaction with mercaptoethanol;

[0028] Figure 6 GPC curves of polymers prepared in Examples 15-19 with different [ByMA]0 / [IAP-1]0 ratios;

[0029] Figure 7 The graph shows the relationship between monomer conversion rate and the molecular weight and molecular weight distribution of the prepared polymer.

[0030] Figure 8 For IAP-1 / i MALDI TOF spectrum of low molecular weight PByMA produced by Bu2Al(BHT) catalytic ByMA polymerization;

[0031] Figure 9 For IAP-1 / i Superimposed GPC curves of Bu2Al(BHT) catalyzed ByMA chain extension (a) and IAP-1 / i Superimposed GPC curves of Bu2Al(BHT) catalyzed ByMA, MMA and AMA block copolymerization (b);

[0032] Figure 10 The 1H NMR spectrum of the in-situ CuAAC reaction of small molecules containing alkenyl, alkynyl and azide groups;

[0033] Figure 11 The superimposed 1H NMR spectra of the in-situ CuAAC reaction of small molecules containing alkenyl, alkynyl and azido groups (top) and the in-situ thiol-olefin reaction with added thiol (bottom);

[0034] Figure 12 The superimposed 1H NMR spectrum of the reaction between alkenyl and alkynyl polymers (bottom) and ethyl azide with CuAAC (top);

[0035] Figure 13 Superimposed tensile curves of self-healing materials prepared from alkenyl and alkynyl polymers before and after repair at 50 °C for 5 h.

[0036] Figure 14 GPC curves of polymers prepared with different [HDEMA]0 / [IAP-1]0 ratios and different Lewis acids in Examples 30-32 are shown.

[0037] Figure 15The superimposed 1H NMR spectra of the conjugated diene polymer (top), triazolinide (bottom), and the addition reaction of the conjugated diene polymer and triazolinide (middle);

[0038] Figure 16 The image shows a superimposed 1H NMR spectrum of the reaction of conjugated dienyl polymers with triazolinediones (top), the reaction of alkynyl polymers with azide compounds (middle), and the reaction of conjugated dienyl and alkynyl polymers through a series of click reactions (bottom).

[0039] Figure 17 This is a schematic diagram illustrating the mechanism of polymer preparation by Lewis acid-base pair catalytic monomer polymerization according to the present invention. Detailed Implementation

[0040] This invention provides an application of Lewis acid-base pairs in the catalytic polymerization of functionalizable monomers, wherein the Lewis acid-base pair comprises a Lewis acid and a Lewis base; and the Lewis base comprises one or more of the following: a Lewis base of formula NHO, a Lewis base of formula IAP, a Lewis base of formula DIAP, and a Lewis base of formula PyAP.

[0041] ;

[0042] In formulas NHO, IAP, DIAP, and PyAP, n = 1 to 9, R1 is hydrogen, alkyl, or phenyl; R2 is hydrogen, alkyl, phenyl, or substituted phenyl; R3 is alkyl, phenyl, or substituted phenyl; R4 is alkyl, phenyl, or substituted phenyl; R5 is hydrogen, alkyl, phenyl, or substituted phenyl; and R6 is hydrogen, alkyl, phenyl, or substituted phenyl.

[0043] In this invention, the application preferably includes the following steps: mixing monomers, Lewis acid-base pairs and organic solvents to carry out a polymerization reaction to obtain a polymer.

[0044] This invention involves mixing a monomer, a Lewis acid-base pair, and an organic solvent to obtain a mixed solution. In this invention, the monomer preferably includes one or more of the following: polyene-containing acrylate monomers, polyene-containing acrylamide monomers, alkynyl-containing acrylate monomers, alkynyl-containing acrylamide monomers, conjugated diene-containing acrylate monomers, and conjugated diene-containing acrylamide monomers.

[0045] In this invention, the polyolefin-containing acrylate monomer preferably includes one or more of the following monomers: monomer of formula 1, monomer of formula 2, monomer of formula 3, monomer of formula 4, monomer of formula 5, monomer of formula 6, monomer of formula 7, monomer of formula 8, monomer of formula 9, monomer of formula 10, monomer of formula 11, monomer of formula 12, monomer of formula 13, monomer of formula 14, monomer of formula 15, monomer of formula 16, monomer of formula 17, monomer of formula 18, monomer of formula 19, monomer of formula 20, monomer of formula 21, monomer of formula 22, monomer of formula 23, monomer of formula 24, monomer of formula 25, monomer of formula 26, monomer of formula 27, monomer of formula 28, monomer of formula 29, monomer of formula 30, monomer of formula 31, monomer of formula 32, monomer of formula 33, monomer of formula 34, monomer of formula 35, and monomer of formula 36.

[0046] ;

[0047] In equations 1 to 36, R 1 For -H or -CH3, R 2 For -CH3 or -CH2CH3, R 3 It is -H or C1~C10 alkyl.

[0048] In this invention, the C1 to C10 alkyl groups in Formulas 1 to 36 preferably include -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -CH(CH3)CH2CH3 or -C(CH3)3.

[0049] In this invention, the polyene-containing acrylamide monomer preferably includes one or more of the following: monomer of formula 37, monomer of formula 38, monomer of formula 39, or monomer of formula 40:

[0050] ;

[0051] In equations 37 to 40, R 1 For -H or -CH3, R 3 It is -H or C1~C10 alkyl.

[0052] In this invention, in Formulas 37 to 40, the C1 to C10 alkyl groups preferably include -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -CH(CH3)CH2CH3 or -C(CH3)3.

[0053] In this invention, the alkynyl acrylate monomer preferably includes one or more of the following: monomers of formula 41, formula 42, formula 43, formula 44, formula 45, formula 46, formula 47, formula 48, formula 49, formula 50, formula 51, formula 52, formula 53, formula 54, formula 55, formula 56, formula 57, formula 58, formula 59, formula 60, formula 61, and formula 62.

[0054] ;

[0055] In equations 41 to 62, R 1 For -H or -CH3, R 2 For -CH3 or -CH2CH3, R 3 It is -H or C1~C10 alkyl.

[0056] In this invention, in formulas 41 to 62, the C1 to C10 alkyl groups preferably include -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -CH(CH3)CH2CH3 or -C(CH3)3.

[0057] In this invention, the alkynyl-containing acrylamide monomer preferably includes one or more of the monomers of formula 63 and formula 64:

[0058] ;

[0059] In equations 63 and 64, R 1 For -H or -CH3, R 3 It is -H or C1~C10 alkyl.

[0060] In this invention, in Formulas 63 to 64, the C1 to C10 alkyl groups preferably include -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -CH(CH3)CH2CH3 or -C(CH3)3.

[0061] In this invention, the conjugated diene acrylate monomer preferably includes one or more of the following: monomers of formula 65, formula 66, formula 67, formula 68, formula 69, formula 70, formula 71, formula 72, formula 73, formula 74, formula 75, formula 76, formula 77, formula 78, formula 79, formula 80, formula 81, formula 82, formula 83, and formula 84.

[0062] ;

[0063] In equations 65 to 84, R 1 For -H or -CH3, R 2 For -CH3 or -CH2CH3, R 3 It is -H or C1~C10 alkyl.

[0064] In this invention, in formulas 65 to 84, the C1 to C10 alkyl groups preferably include -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -CH(CH3)CH2CH3 or -C(CH3)3.

[0065] In this invention, the conjugated diene acrylamide monomer preferably includes one or more of the monomers of formula 85 and formula 86:

[0066] ;

[0067] In equations 85 and 86, R 1 For -H or -CH3, R 3 It is -H or C1~C10 alkyl.

[0068] In this invention, in Formulas 85 to 86, the C1 to C10 alkyl groups preferably include -CH3, -CH2CH3, -CH2CH2CH3, -CH(CH3)2, -CH2CH2CH2CH3, -CH2CH(CH3)CH3, -CH(CH3)CH2CH3 or -C(CH3)3.

[0069] In specific embodiments of the present invention, the monomer preferably includes one or more of butyl methacrylate, propargyl methacrylate, and methacrylate;

[0070] .

[0071] In this invention, the molar ratio of the monomer to the Lewis base in the Lewis acid-base pair is preferably 15 to 50,000:1, specifically 15:1, 50:1, 100:1, 200:1, 500:1, 1000:1, 2000:1, 10000:3, 10000:1, 15000:1, 20000:1, 30000:1, 40000:1, or 50000:1.

[0072] In this invention, the Lewis acid-base pair is preferably added in the form of Lewis acid solution and Lewis base solution, respectively.

[0073] In this invention, the organic solvent preferably includes one or more of benzene homologues, furan compounds, amide compounds, and substituted benzenes, more preferably benzene homologues; the benzene homologues are preferably toluene; the furan compounds are preferably tetrahydrofuran; the amide compounds are preferably N,N-dimethylformamide; and the substituted benzenes preferably include one or two of fluorobenzene and chlorobenzene.

[0074] In this invention, the concentration of the monomer in the mixed solution is preferably not less than 0.2 M, specifically 0.2 M, 0.5 M, 0.94 M, 1 M, 2 M or 4 M.

[0075] In this invention, the mixing of the monomer, Lewis acid-base pair, and organic solvent is preferably carried out as follows: the monomer and a first portion of the organic solvent are mixed to obtain a monomer solution; the Lewis acid and a second portion of the organic solvent are mixed to obtain a Lewis acid solution; the Lewis base and a third portion of the organic solvent are mixed to obtain a Lewis base solution; the monomer solution, the Lewis acid solution, and the remaining portion of the organic solvent are mixed to obtain a premix; and then the premix and the Lewis base solution are mixed. This invention, by controlling the order and steps of feeding, requires less catalyst, achieves faster polymerization, does not require stringent conditions, exhibits no crosslinking during polymerization, and precisely synthesizes polymers with controllable sequences and structural compositions containing functionalizable sites, such as random or block copolymers, especially non-crosslinked acetylene-containing polymers.

[0076] After obtaining the mixed solution, the present invention performs a polymerization reaction on the obtained mixed solution to obtain a polymer. In the present invention, the temperature of the polymerization reaction is preferably -50~100 ℃, specifically -50 ℃, -30 ℃, -10 ℃, 0 ℃, 15 ℃, 25 ℃, 45 ℃, 65 ℃, 85 ℃ or 100 ℃, and the holding time is preferably 10 s~72 h, specifically 10 s, 30 s, 1 min, 10 min, 30 min, 1 h, 10 h, 30 h, 50 h or 72 h.

[0077] The mechanism of Lewis acid-base pair catalyzing monomer polymerization in this invention is as follows: Figure 17 As shown: First, chain initiation occurs: Lewis base nucleophilically attacks the monomer activated by Lewis acid, forming a zwitterionic active species; then, chain growth occurs: the end of the active chain nucleophilically attacks the monomer activated by Lewis acid, and the attacked site is a double bond conjugated with the carbonyl group.

[0078] In the specific Lewis acid-base pairs used in this invention, the Lewis acid preferably includes one or more of the following: Lewis acid of formula A-1, Lewis acid of formula A-2, Lewis acid of formula A-3, and Lewis acid of formula A-4.

[0079]

[0080] Formula A-1; Formula A-2; Formula A-3; Formula A-4;

[0081] In formulas A-1 to A-4, R1 is an alkyl or halogen; R2 is hydrogen, alkyl, substituted alkyl, or halogen; and R3 is hydrogen, alkyl, or halogen.

[0082] In this invention, R1 in formulas A-1 to A-4, the alkyl group is preferably a C1 to C10 alkyl group; the C1 to C10 alkyl group is preferably a C1 to C10 straight-chain alkyl group or a C1 to C10 branched-chain alkyl group; the C1 to C10 straight-chain alkyl group preferably includes methyl or ethyl; the C1 to C10 branched-chain alkyl group preferably includes isopropyl or isobutyl; the halogen preferably includes fluorine, chlorine or bromine.

[0083] In this invention, R2 in formulas A-1 to A-4, the alkyl group is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl or ethyl; the C1-C10 branched alkyl group preferably includes isopropyl, isobutyl or tert-butyl; the substituted alkyl group is preferably a polysubstituted C1-C10 alkyl group; the polysubstituted C1-C10 alkyl group is preferably trifluoromethyl; the halogen preferably includes fluorine, chlorine or bromine.

[0084] In this invention, R3 in formulas A-1 to A-4, the alkyl group is preferably a C1 to C10 alkyl group; the C1 to C10 alkyl group is preferably a C1 to C10 straight-chain alkyl group; the C1 to C10 straight-chain alkyl group preferably includes methyl or ethyl; the halogen preferably includes fluorine, chlorine or bromine.

[0085] In this invention, the Lewis acid preferably includes bis(2,6-di-tert-butyl-4-methylphenoxy)methylaluminum (MeAl(BHT)2), tris(pentafluorophenyl)aluminum (Al(C6F5)3), and (2,6-di-tert-butyl-4-methylphenoxy)diisobutylaluminum (MeAl(BHT)2). i Bu2Al(BHT)), bis(2,6-di-tert-butyl-4-methylphenoxy)isobutylaluminum ( i One or more of BuAl(BHT)2 and trimethylaluminum (AlMe3).

[0086] In this invention, R1 in formula NHO, formula IAP, formula DIAP and formula PyAP is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched-chain alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl, ethyl, n-propyl or n-butyl; the C1-C10 branched-chain alkyl group preferably includes isopropyl, isobutyl or tert-butyl.

[0087] In this invention, R2 in formulas NHO, IAP, DIAP, and PyAP is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched-chain alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl, ethyl, n-propyl, or n-butyl; the C1-C10 branched-chain alkyl group preferably includes isopropyl, isobutyl, or tert-butyl; the substituted phenyl group preferably includes alkylphenyl or halophenyl; the alkylphenyl group is preferably a polyalkylphenyl group; the polyalkylphenyl group preferably includes 2,6-diisopropylphenyl or 1,3,5-trimethylphenyl; the halophenyl group is preferably a fluorophenyl group; the fluorophenyl group is preferably a pentafluorophenyl group.

[0088] In this invention, R3 in formulas NHO, IAP, DIAP, and PyAP is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched-chain alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl, ethyl, n-propyl, or n-butyl; the C1-C10 branched-chain alkyl group preferably includes isopropyl, isobutyl, or tert-butyl; the substituted phenyl group preferably includes alkylphenyl or halophenyl; the alkylphenyl group is preferably a polyalkylphenyl group; the polyalkylphenyl group preferably includes 2,6-diisopropylphenyl or 1,3,5-trimethylphenyl; the halophenyl group is preferably a fluorophenyl group; the fluorophenyl group is preferably a pentafluorophenyl group.

[0089] In this invention, R4 in formulas NHO, IAP, DIAP, and PyAP is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched-chain alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl, ethyl, n-propyl, or n-butyl; the C1-C10 branched-chain alkyl group preferably includes isopropyl, isobutyl, or tert-butyl; the substituted phenyl group preferably includes alkylphenyl or halophenyl; the alkylphenyl group is preferably a polyalkylphenyl group; the polyalkylphenyl group preferably includes 2,6-diisopropylphenyl or 1,3,5-trimethylphenyl; the halophenyl group is preferably a fluorophenyl group; the fluorophenyl group is preferably a pentafluorophenyl group.

[0090] In this invention, R5 in formulas NHO, IAP, DIAP, and PyAP, the alkyl group is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl, ethyl, n-propyl, or n-butyl; the C1-C10 branched alkyl group preferably includes isopropyl, isobutyl, or tert-butyl; the substituted phenyl group preferably includes alkylphenyl or halophenyl; the alkylphenyl group is preferably a polyalkylphenyl group; the polyalkylphenyl group preferably includes 2,6-diisopropylphenyl or 1,3,5-trimethylphenyl; the halophenyl group is preferably a fluorophenyl group; the fluorophenyl group is preferably a pentafluorophenyl group.

[0091] In this invention, R6 in formulas NHO, IAP, DIAP, and PyAP is preferably a C1-C10 alkyl group; the C1-C10 alkyl group is preferably a C1-C10 straight-chain alkyl group or a C1-C10 branched alkyl group; the C1-C10 straight-chain alkyl group preferably includes methyl, ethyl, n-propyl, or n-butyl; the C1-C10 branched alkyl group preferably includes isopropyl, isobutyl, or tert-butyl; the substituted phenyl group preferably includes alkylphenyl or halophenyl; the alkylphenyl group is preferably a polyalkylphenyl group; the polyalkylphenyl group preferably includes 2,6-diisopropylphenyl or 1,3,5-trimethylphenyl; the halophenyl group is preferably a fluorophenyl group; the fluorophenyl group is preferably a pentafluorophenyl group.

[0092] In this invention, the Lewis base preferably includes one or more of nitrogen heterocyclic olefin-1 (NHO-1, structure as NHO-1) and guanidinophosphine base-1 (IAP-1, structure as IAP-1).

[0093] .

[0094] In this invention, the molar ratio of the Lewis acid to the Lewis base is preferably not less than 2:1, specifically 20:1, 16:1, 8:1, 4:1, 3:1, or 2:1. This invention utilizes the above-mentioned amounts of Lewis acid and Lewis base: one equivalent of the Lewis base attacks the activated monomer to form a zwitterionic reactive species; one equivalent of the Lewis acid stabilizes the polymer chain ends; and the remaining (at least one equivalent) Lewis acid activates the monomer. The greater the amount of Lewis acid used, the faster the polymerization reaction rate.

[0095] In this invention, the method for preparing the Lewis acid-base pair preferably includes the following steps: mixing a Lewis acid and a Lewis base to obtain the Lewis acid-base pair.

[0096] In this invention, the Lewis acid and Lewis base are preferably mixed by stirring.

[0097] To further illustrate the present invention, the following detailed description of the invention's solutions, in conjunction with the accompanying drawings and embodiments, is provided, but should not be construed as limiting the scope of protection of the present invention.

[0098] Examples 1-13

[0099] The Lewis acid-base pairs used in Examples 1-13 were Lewis bases of different formulas (denoted as LB) combined with different Lewis acids (denoted as LA); Examples 1-13 catalyzed the polymerization of allyl methacrylate (AMA, denoted as M), including the following steps:

[0100] ;

[0101] 296 mg (2.35 mmol) of AMA was dissolved in 500 µL of toluene to obtain a monomer solution. Then, a toluene solution of LA was added to the monomer solution, and after stirring for 1 minute, more toluene was added to maintain a monomer concentration of 0.94 M in the reaction system, resulting in a premix. A toluene solution of LB was then added to the premix to obtain a mixed solution with a total volume of 2.5 mL. Polymerization was then carried out at room temperature to obtain the polymer. The molar ratios of M, LA, and LB, and the polymerization time are shown in Table 1.

[0102] Monomer conversion was determined using 1H NMR spectroscopy and measured using gel permeation chromatography-light scattering. M w and Ð The results are shown in Table 1, where the initiation efficiency ( I The calculation method for () is as follows:

[0103] I = M n (theory) / M n (actual);

[0104] M n (Theoretical) = [MW(AMA)]×([AMA]0 / [IAP]0)×monomer conversion rate+MW(terminal group).

[0105] Table 1 Test results of Examples 1-13

[0106]

[0107] As can be seen from Table 1, the three Lewis acids (Al(C6F5)...) 3、 MeAl(BHT) 2、 iBu2Al(BHT) combined with four Lewis bases (IAP-1, IAP-2, IAP-3, IAP-4) exhibits high polymerization activity. All polymerization reactions can achieve nearly 100% monomer conversion in a short time without cross-linking. As the monomer ratio increases, the molecular weight of the resulting polymer increases linearly and maintains a narrow distribution, with an initiation efficiency of nearly 100%.

[0108] Examples 14-19

[0109] The Lewis acid-base pairs used in Examples 14-19 were IAP-1 compounds (denoted as LB) i Bu2Al(BHT) (denoted as LA); Examples 14-19 catalyze the polymerization of butyl methacrylate (ByMA, denoted as M), including the following steps:

[0110] 324 mg (2.35 mmol) of ByMA was dissolved in 500 µL of toluene to obtain a monomer solution; then, the monomer solution was added... i A toluene solution of Bu2Al(BHT) was stirred for 1 minute, and then toluene was added to ensure that the monomer concentration in the reaction system was 0.94 M, resulting in a premix. A toluene solution of compound IAP-1 was then added to the premix to obtain a mixed solution with a total volume of 2.5 mL. The polymerization reaction was then carried out at room temperature to obtain the polymer. The molar ratios of M, LA, and LB, and the polymerization time are shown in Table 2.

[0111] Monomer conversion was determined using 1H NMR spectroscopy and measured using gel permeation chromatography-light scattering. M w and Ð The results are shown in Table 2, where the initiation efficiency ( I The calculation method for () is as follows:

[0112] I = M n (theory) / M n (actual);

[0113] M n (Theoretical) = [MW(ByMA)]×([ByMA]0 / [IAP-1]0)×monomer conversion rate + MW(terminal group).

[0114] Table 2 Test results of Examples 14-19

[0115]

[0116] As shown in Table 2, all polymerization reactions can achieve 100% monomer conversion in a short time, and polymerization is completed. With the increase of monomer ratio, the molecular weight of the resulting polymer increases linearly and maintains a narrow distribution, with an initiation efficiency close to 100%.

[0117] Examples 20-24

[0118] Examples 20-24 utilize compound NHO-1 (denoted as LB) in combination with different Lewis acids (denoted as LA) to catalyze the polymerization of butyl methacrylate (ByMA) (denoted as M), including the following steps:

[0119] 324 mg (2.35 mmol) of ByMA was dissolved in 500 µL of toluene to obtain a monomer solution. Then, a toluene solution of Lewis acid was added to the monomer solution, and after stirring for 1 minute, toluene was added again to ensure that the concentration of monomer in the reaction system was 0.94 M, thus obtaining a premix. A toluene solution of compound NHO-1 was then added to the premix to obtain a mixed solution with a total volume of 2.5 mL. The polymerization reaction was then carried out at room temperature to obtain the polymer. The molar ratios of M, LA, and LB, and the polymerization time are shown in Table 3. The test methods were the same as above, and the results are shown in Table 3.

[0120] Table 3 Test results of Examples 20-24

[0121]

[0122] Table 3 shows that by using NHO-1 as the LB and combining it with different LAs, ByMA polymerization can be achieved; among them, high acidity (Al(C6F5)3) or moderate acidity and moderate steric hindrance (MeAl(BHT)2) can be achieved. i The LA of Bu2Al(BHT) can achieve complete monomer conversion, yielding polymers with molecular weights close to the expected and narrow molecular weight distributions, moderate acidity but significant steric hindrance. i BuAl(BHT)2) or less acidic LA (AlMe3) exhibit slow polymerization rates.

[0123] Examples 25-29

[0124] Examples 25-29 utilize compounds of formula IAP-1 combined with different Lewis acids to catalyze the polymerization of butyl methacrylate (ByMA), including the following steps:

[0125] 324 mg (2.35 mmol) of ByMA was dissolved in 500 µL of toluene to obtain a monomer solution. Then, a toluene solution of Lewis acid was added to the monomer solution, and after stirring for 1 minute, toluene was added again to ensure that the concentration of monomer in the reaction system was 0.94 M, thus obtaining a premix. A toluene solution of compound IAP-1 was added to the premix to obtain a mixed solution with a total volume of 2.5 mL. The polymerization reaction was then carried out at room temperature to obtain the polymer. The molar ratios of M, LA, and LB, and the polymerization reaction time are shown in Table 4. The test methods were the same as above, and the results are shown in Table 4.

[0126] Table 4 Test results of Examples 25-29

[0127]

[0128] As shown in Table 4, by using IAP-1 as the LB and combining it with different LAs, ByMA polymerization can be achieved; among them, the acidity and steric hindrance are moderate ( i LA with Bu2Al(BHT) can achieve complete monomer conversion, yielding polymers with the expected molecular weight and narrow molecular weight distribution. LA with higher acidity (Al(C6F5)3) or moderate acidity and moderate steric hindrance (MeAl(BHT)2) can achieve complete monomer conversion, but the resulting molecular weight is lower than the theoretical molecular weight. LA with moderate acidity but greater steric hindrance... i BuAl(BHT)2) or less acidic LA (AlMe3) exhibit slow polymerization rates.

[0129] Examples 30-32

[0130] Examples 30-32 utilize compounds of formula IAP-1 combined with different Lewis acids to catalyze the polymerization of (2,4-hexadiene) methacrylate (HDEMA), including the following steps:

[0131] ;

[0132] 390 mg (2.35 mmol) of HDEMA was dissolved in 500 µL of toluene to obtain a monomer solution. Then, a toluene solution of Lewis acid was added to the monomer solution, and after stirring for 1 minute, toluene was added again to ensure that the concentration of monomer in the reaction system was 0.94 M, thus obtaining a premix. A toluene solution of compound IAP-1 was added to the premix to obtain a mixed solution with a total volume of 2.5 mL. The polymerization reaction was then carried out at room temperature to obtain the polymer. The molar ratios of M, LA, and LB, and the polymerization reaction time are shown in Table 5. The test methods were the same as above, and the results are shown in Table 5.

[0133] Monomer conversion was tested using 1H NMR spectroscopy and gel permeation chromatography was used for further analysis. Mn and Ð The results are shown in Table 5, where the initiation efficiency ( I The calculation method for () is as follows:

[0134] I = M n (theory) / M n (actual);

[0135] M n (Theoretical) = [MW(HDEMA)]×([HDEMA]0 / [IAP-1]0)×monomer conversion rate + MW(terminal group).

[0136] Table 5 Test results of Examples 30-32

[0137]

[0138] As shown in Table 5, using IAP-1 as the LB, combined with different LAs ( i Bu2Al(BHT) and MeAl(BHT)2) have high polymerization activity and can achieve complete conversion of HDEMA in a short time.

[0139] Test Example 1

[0140] GPC analysis was performed on the polymers prepared in Examples 3, 7-13 with different [AMA]0 / [IAP-1]0 ratios, and the results are as follows: Figure 1 As shown. According to Figure 1 It can be seen that as the ratio of [AMA]0 / [IAP-1]0 increases, the molecular weight of the prepared polymer gradually increases, proving that the present invention can obtain a polymer with the expected molecular weight by controlling the amount of [AMA]0 / [IAP-1]0.

[0141] Test Example 2

[0142] The relationship between monomer conversion rate and the molecular weight and molecular weight distribution of the prepared polymer was tested, referring to Example 9, with the raw material ratio being [AMA]0 / [IAP-1]0 = 1600:1. The results are as follows. Figure 2 As shown, the low molecular weight PAMA produced by AMA polymerization was subjected to MALDI TOF testing, and the results are as follows. Figure 3 As shown.

[0143] according to Figures 2-3 It can be seen that the polymer molecular weight increases linearly with the polymerization reaction and maintains a narrow distribution. No back-biting occurs at the polymer chain ends, indicating that IAP-1 / i Bu2Al(BHT)-catalyzed AMA polymerization exhibits the characteristics of living polymerization.

[0144] Test Example 3

[0145] For IAP-1 / i GPC curve overlay analysis was performed on Bu2Al(BHT) catalyzed AMA chain elongation and catalyzed MMA / AMA block copolymerization, IAP-1 / i Bu2Al(BHT) can catalyze multiple chain extensions of AMA monomers or multiple block copolymerizations with other methacrylate monomers. The specific test method is as follows: 296 mg (2.35 mmol) of AMA is dissolved in 500 µL of toluene, and then... i A toluene solution of Bu2Al(BHT) was stirred for 1 minute, followed by the addition of toluene. A toluene solution of compound IAP-1 was then added to obtain a mixed solution with a total volume of 2.5 mL. After complete monomer conversion, the same amount of AMA or methyl methacrylate (MMA) (2.35 mmol) was added. This process was repeated several times until all monomers were completely converted. The reaction flask was then removed from the glove box, and the polymerization reaction was terminated by adding 5% HCl / methanol solution. The polymer was filtered out, washed thoroughly with methanol, and dried under vacuum at 50 °C to constant weight. The molecular weight and molecular weight distribution of the obtained polymer were determined by gel permeation chromatography, and the results are shown below. Figure 4 As shown.

[0146] according to Figure 4 It can be seen that, without quenching, the polymerization reaction can achieve further polymer chain growth through continuous feeding, which further verifies the IAP-1 / i Bu2Al(BHT)-catalyzed AMA polymerization exhibits the characteristics of living polymerization.

[0147] Test Example 4

[0148] Combining thiol-olefin addition click reactions, alkenyl-containing polymers can serve as an efficient platform for post-modification preparation of functional polymer materials. 1H NMR analysis of the thiol-olefin addition reaction of poly(allyl methacrylate) (PAMA) with mercaptoethanol showed that all alkenyl groups in the polymer were converted to hydroxyl groups, as shown in the results. Figure 5 As shown.

[0149] according to Figure 5 It can be seen that the alkenyl groups contained in the polymer can be quantitatively converted into specific functional groups. Therefore, alkenyl-containing polymers can be regarded as conversion platforms. Through efficient post-modification reactions, different structural groups can be introduced, thereby endowing polymer materials with a variety of properties.

[0150] Test Example 5

[0151] GPC analysis was performed on the polymers prepared in Examples 15-19 with different [ByMA]0 / [IAP-1]0 ratios, and the results are as follows: Figure 6 As shown. According to Figure 6 It can be seen that as the ratio of [ByMA]0 / [IAP-1]0 increases, the molecular weight of the prepared polymer gradually increases, proving that the present invention can obtain a polymer with the expected molecular weight by controlling the amount of [ByMA]0 / [IAP-1]0.

[0152] Test Example 6

[0153] The relationship between monomer conversion rate and the molecular weight and molecular weight distribution of the prepared polymer was tested, referring to Example 17, with the raw material ratio being [ByMA]0 / [IAP-1]0 = 800:1. The results are as follows. Figure 7 As shown, the low molecular weight PByMA produced by ByMA polymerization was tested by MALDI TOF, and the results are as follows. Figure 8 As shown.

[0154] according to Figures 7-8 It can be seen that the polymer molecular weight increases linearly with the polymerization reaction and maintains a narrow distribution. No back-biting occurs at the polymer chain ends, indicating that IAP-1 / i Bu2Al(BHT)-catalyzed ByMA polymerization exhibits the characteristics of living polymerization.

[0155] Test Example 7

[0156] For IAP-1 / i GPC curve overlay analysis was performed on Bu2Al(BHT) catalyzed ByMA chain extension and catalyzed block copolymerization of ByMA, MMA, and AMA. (IAP-1 / ) i Bu2Al(BHT) can catalyze multiple chain extensions of ByMA monomers or multiple block copolymerizations with other methacrylate monomers. The specific testing method is as follows: 324 mg (2.35 mmol) of ByMA is dissolved in 500 µL of toluene, and then... i A toluene solution of Bu2Al(BHT) was stirred for 1 minute, followed by the addition of toluene. A toluene solution of compound IAP-1 was then added to obtain a mixed solution with a total volume of 2.5 mL. After complete monomer conversion, the same amount of ByMA, allyl methacrylate (AMA), or methyl methacrylate (MMA) (2.35 mmol) was added. This process was repeated several times until all monomers were completely converted. The reaction flask was then removed from the glove box, and the polymerization reaction was terminated by adding 5% HCl / methanol solution. The polymer was filtered out, washed thoroughly with methanol, and dried under vacuum at 50 °C to constant weight. The molecular weight and molecular weight distribution of the obtained polymer were determined by gel permeation chromatography, and the results are shown below. Figure 9 As shown.

[0157] according to Figure 9 It can be seen that, without quenching, the polymerization reaction can achieve further polymer chain growth through continuous feeding, which further verifies the IAP-1 / i Bu2Al(BHT)-catalyzed ByMA polymerization exhibits the characteristics of living polymerization.

[0158] Test Example 8

[0159] Polymers containing both alkyne and alkenyl groups can serve as an efficient platform for post-modification preparation of functional polymer materials, when combined with click reactions or other highly efficient organic reactions. In-situ Cu(I)-catalyzed azido-alkyne cycloaddition reactions (CuAAC reactions) of small molecules containing alkenyl, alkyne, and azido groups were analyzed by 1H NMR spectroscopy, and the results are as follows: Figure 10 As shown. The in-situ CuAAC reaction of small molecules containing alkenyl, alkynyl, and azido groups (top) and the in-situ thiol-olefin reaction with added thiol (bottom) were analyzed by superposition of 1H NMR spectra. The results are as follows. Figure 11 As shown.

[0160] according to Figures 10-11 It can be seen that the alkynyl and alkenyl groups that coexist in the system can be converted separately in one pot through sequential reactions; extended to polymers, two functionalizable sites can be introduced into different structural groups through continuous post-modification reactions, thereby endowing polymer materials with a variety of properties.

[0161] Test Example 9

[0162] Polymers containing alkynyl and alkenyl groups can be transformed through CuAAC reaction and radical addition reaction of double bonds to introduce different functional groups. For example, a triazole group is introduced by reacting the alkynyl group with ethyl azide, and then a flexible alkyl chain and disulfide bond are introduced by reacting the double bond with diallyl disulfide. Utilizing various dynamic forces such as π-π stacking, dynamic disulfide bonds, and microphase separation, self-healing materials can be constructed. The CuAAC reaction of alkenyl and alkynyl polymers (bottom) with ethyl azide (top) was analyzed by superimposed 1H NMR spectroscopy, and the results are as follows: Figure 12 As shown. According to Figure 12 It can be seen that after the CuAAC reaction, the alkynyl signal in the original polymer disappears and the triazole signal appears, while the alkenyl signal remains unchanged. This proves that the modification reaction can efficiently and specifically convert the alkynyl group in the polymer without affecting other structures.

[0163] Tensile superposition analysis was performed on self-healing materials prepared from alkenyl and alkynyl polymers before and after repair at 50 °C for 5 h. The results are as follows: Figure 13 As shown. According to Figure 13It can be seen that the polymer (black) modified with both alkynyl and alkenyl components (two-component modification) exhibits a better repair efficiency of 96.9%; the unmodified polymer (red) has a repair efficiency of 51.6%; the single-component modified alkynyl polymer (blue) has a repair efficiency of 59.1%; and the single-component modified alkenyl polymer (green) has a repair efficiency of 49.2%. This proves that only by simultaneously modifying both alkynyl and alkenyl components can good self-healing properties be achieved.

[0164] Test Case 10

[0165] GPC analysis was performed on polymers prepared using different [HDEMA]O / [IAP-1]O ratios and different Lewis acids in Examples 30-32. The results are as follows: Figure 14 As shown. According to Figure 14 It can be seen that the obtained polymer GPC curves all show a single peak, and the polymers have a narrow molecular weight distribution.

[0166] Test Example 11

[0167] Combined with click reactions, polymers containing both conjugated diene and alkynyl groups can serve as an efficient platform for post-modification preparation of functional polymer materials. The addition click reaction of poly(2,4-hexadiene) methacrylate (PHDEMA) with triazolinone (TAD) was analyzed by superposition of 1H NMR spectroscopy, and the results are as follows: Figure 15 As shown. Comparing the NMR spectrum of poly(2,4-hexadiene) ester (top), the NMR spectrum of triazolinone (bottom), and the complete reaction of the conjugated dienyl group with triazolinone (middle).

[0168] A sequential post-modification reaction was performed on polymers containing conjugated diene and alkynyl groups with triazolinone and azide compounds. The conjugated diene group introduced a specific functional group through an addition click reaction with the triazolinone, while the alkynyl group introduced another specific functional group through an azide-alkynyl cycloaddition (CuAAC) reaction with the azide compound. The sequential click reaction was analyzed by 1H NMR superposition, and the results are as follows: Figure 16 As shown. Comparing the NMR spectra of poly(2,4-hexadiene) methacrylate modified with NMR (top) and poly(butyl methacrylate) modified with NMR (middle), it can be seen that after the copolymer of poly(2,4-hexadiene) methacrylate and poly(butyl methacrylate) undergoes a sequential click reaction, the conjugated diene and alkynyl groups are completely converted into specific groups (bottom).

[0169] according to Figures 15-16 It can be seen that the conjugated diene and alkynyl groups that coexist in the system can be converted separately in one pot through sequential reactions. That is, through continuous post-modification reactions, two functionalizable sites can be introduced into different structural groups, thereby endowing the polymer material with a variety of properties.

[0170] As can be seen from the above embodiments, the present invention can catalyze the active and controllable polymerization of functionalizable monomers through specific Lewis acid-base pairs, and obtain polymers with well-defined structures containing functionalizable sites. The position and density of functionalizable sites can be easily adjusted, overcoming the problem that functionalizable sites are difficult to quickly and completely convert into specific groups due to the large steric hindrance of polymers.

[0171] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. Other embodiments can be obtained based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. The application of a Lewis acid-base pair in the catalytic living polymerization of functionalizable monomers, wherein the Lewis acid-base pair comprises a Lewis acid and a Lewis base; The Lewis base is a Lewis base of formula IAP-1; ； The monomer is butyl methacrylate; The Lewis acid includes bis(2,6-di-tert-butyl-4-methylphenoxy)methylaluminum or (2,6-di-tert-butyl-4-methylphenoxy)diisobutylaluminum; The application includes the following steps: A polymer is obtained by mixing monomers, Lewis acid-base pairs, and organic solvents. The polymerization reaction is carried out at a temperature of 15~25 ℃ and the reaction time is 30 s~10 min. The molar ratio of the monomer and the Lewis base in the Lewis acid-base pair is 100~1000:1; The molar ratio of the Lewis acid to the Lewis base is 2:

1.

2. The application according to claim 1, characterized in that, The concentration of the monomer in the mixed solution is not less than 0.2 M.

3. The application according to claim 1, characterized in that, The organic solvent includes one or more of furans, amides, and substituted benzenes.

4. The application according to claim 1, characterized in that, The mixing of the monomer, Lewis acid-base pair, and organic solvent is as follows: the monomer is mixed with a first portion of the organic solvent to obtain a monomer solution; the Lewis acid is mixed with a second portion of the organic solvent to obtain a Lewis acid solution; the Lewis base is mixed with a third portion of the organic solvent to obtain a Lewis base solution; the monomer solution, the Lewis acid solution, and the remaining portion of the organic solvent are mixed to obtain a premix; and then the premix and the Lewis base solution are mixed.

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