Cyclic polymerization method based on free radical migration and polymer thereof

Abstract

The invention discloses a cyclization polymerization method based on free radical migration and a polymer thereof, and belongs to the technical field of polymerization of cyclization polymers. A polymeric monomer and an initiator are mixed and heated to react to obtain the polymer. Wherein the polymeric monomer is a diene compound, and the diene compound comprises an electron withdrawing group and a transferable functional group; the initiator includes a compound capable of generating free radicals under light and / or thermal conditions. By utilizing a free radical migration strategy, the initiator can generate free radicals to initiate the polymerization monomer to perform cyclization polymerization reaction to form the cyclized polymer only by providing a heating condition and / or a light condition, the whole reaction process is easy to operate, the reaction condition is mild, auxiliary aids such as a catalyst do not need to be added, the polymerization cost is relatively low, the conversion rate is high, and the method is suitable for industrial production. The obtained polymer is high in cyclization degree, relatively high in molecular weight, relatively narrow in molecular weight distribution and stable in structure.

Description

Technical Field

[0001] The invention relates to the technical field of cyclopolymer polymerization, and in particular to a cyclopolymerization method based on free radical migration and a polymer thereof. Background Art

[0002] Hydrocarbon polymers with five-membered or six-membered rings in the repeating unit are expected to have high optical transparency, thermal stability and mechanical strength. For example, the cyclic polymer COP developed and produced by Japan's Zeon Corporation for medical optical components and high-end pharmaceutical packaging materials. Common reactions for obtaining ring-containing polymers include ring-opening metathesis polymerization of bicyclic olefins (such as norbornene) and addition polymerization of cyclic olefins (including cyclopentene and norbornene) catalyzed by transition metal complexes; copolymerization of acyclic olefins and cyclic olefins to obtain polymers containing random rings along the polymer chain; cyclic polymerization of non-conjugated dienes to grow the polymer and form five-membered to eight-membered rings along the polymer, and provide polymers with these ring units; cyclic polymerization of dienes and copolymerization of olefins and dienes to obtain polymers with cyclic groups along the polymer chain, which are mainly generated using early transition metal complexes as catalysts. Among them, the polymerization reaction of linear polymers with cyclic structure repeating units formed by non-conjugated diene compounds is called cyclopolymerization. Its products have high heat resistance, so cyclopolymerization is a means of preparing heat-resistant polymers.

[0003] The cyclopolymerization of diene compounds can be divided into two categories: metal-catalyzed cyclopolymerization and free radical-involved cyclopolymerization. Many catalytic systems have been developed for metal-catalyzed cyclopolymerization, such as Ziegler-Natta catalytic system, metallocene catalytic system (including di- and mono-metallocene compounds), non-metallocene transition metal catalytic system, and rare earth catalytic system. However, due to the high reactivity of metal catalysts (Pd, Ni, etc.) with olefins, the types of rings in the repeating units of the polymer products are often not unique, and the reaction conditions are harsh, the catalysts are expensive, and recovery and purification are difficult. Free radical-mediated diene cyclopolymerization has the advantages of low cost and no metal doping compared to metal-catalyzed polymerization. The disadvantage is that the monomer structure is special, and it is often necessary to introduce electron-withdrawing groups next to the olefin to increase the ability of the olefin to capture free radicals between molecules, which leads to an increase in the synthesis steps of the monomer, reduces the universality of the reaction and increases the reaction cost. The generated electron-deficient free radicals will also be directly added to the next olefin molecule without cyclization, resulting in a decrease in the proportion of rings in the polymer and the retention of side chains. To this end, the present invention aims at solving the problem of cyclopolymerization of non-conjugated dienes from the root and develops a new synthesis method. Summary of the invention

[0004] The main purpose of the present invention is to provide a cyclopolymerization method based on free radical migration and a polymer thereof which has simple operation, mild process conditions, high conversion rate and low cost.

[0005] To achieve the above object, the present invention provides a cyclopolymerization method based on free migration, comprising the following steps: mixing a polymerization monomer and an initiator, and heating the mixture to obtain a polymer;

[0006] in,

[0007] The polymerizable monomer is a diene compound, which includes an electron-withdrawing group and a mobile functional group. The initiator includes a compound that can generate free radicals under light conditions and / or heat conditions.

[0008] In some embodiments of the present application, the polymerizable monomer comprises the following structural formula:

[0009] R 1 Including electron withdrawing groups or mobile functional groups,

[0010] and / or, R 2 Includes electron withdrawing groups or mobile functional groups.

[0011] In some embodiments of the present application, the electron withdrawing group includes -CN, -F, -Cl, -COOR 3 、-SO 2 Ph, -NO 2 , Wherein, the -COOR 3 R 3 Includes fatty chains;

[0012] And / or, the migratable functional group in the polymerizable monomer includes an unsaturated functional group or a heteroatom, the unsaturated functional group includes a cyano group, an aryl group, a heteroaryl group, an oxime group, an alkenyl group, an alkynyl group or a carbonyl group, and the heteroatom includes a halogen atom, silicon or boron.

[0013] In some embodiments of the present application, the initiator includes at least one of an organic peroxide and an azo compound.

[0014] In some embodiments of the present application, the organic peroxide includes at least one of acyl peroxide, hydrogen peroxide, dialkyl peroxide, ester peroxide, ketone peroxide, and dicarbonate peroxide;

[0015] And / or, the azo compound includes at least one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovaleronitrile, azobiscyclohexylcarbonitrile and dimethyl azobisisobutyrate.

[0016] In some embodiments of the present application, the acyl peroxide includes at least one of benzoyl peroxide and lauroyl peroxide;

[0017] And / or, the hydroperoxide includes at least one of cumene hydroperoxide and tert-butyl hydroperoxide;

[0018] And / or, the dialkyl peroxide includes at least one of di-tert-butyl peroxide and dicumyl peroxide;

[0019] And / or, the ester peroxide includes at least one of tert-butyl perbenzoate and tert-butyl peroxyvalerate;

[0020] And / or, the ketone peroxide includes at least one of methyl ethyl ketone peroxide and cyclohexanone peroxide;

[0021] And / or, the dicarbonate peroxide includes at least one of diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate.

[0022] In some embodiments of the present application, the molar ratio of the polymerization monomer to the initiator is 100:(0.5-20);

[0023] And / or, the temperature range of the heating reaction is above 60°C;

[0024] And / or, the heating reaction is carried out in a protective gas atmosphere or air, and the protective gas includes nitrogen or argon;

[0025] And / or, in the step of mixing the polymerization monomer and the initiator, the polymerization monomer and the initiator can also be dissolved and mixed in an organic solvent, and the organic solvent includes at least one of ethanol, acetonitrile, acetone, dimethyl sulfoxide, N,N-dimethylformamide, ethyl acetate, diethylene glycol, and ethylene glycol.

[0026] To achieve the above objectives, the present application also provides a polymer prepared by the cyclopolymerization method based on free radical migration as described above.

[0027] In some embodiments of the present application, the molecular weight of the polymer is above 1000;

[0028] and / or, the polymer has a distribution width PDI of 1.10-5.00;

[0029] And / or, the conversion rate of the polymerization monomer is 20%-95%;

[0030] And / or, the polymer has the following general structural formula:

[0031]

[0032] In the general structural formula, R 1 including electron withdrawing groups;

[0033] In the general structural formula, R 2 Includes mobile groups;

[0034] In the general structural formula, n is a natural number greater than or equal to 1.

[0035] In some embodiments of the present application, the polymer has the following structural formula (I):

[0036]

[0037] In the structural formula (I), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (II):

[0038]

[0039] In the structural formula (II), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (III):

[0040]

[0041] In the structural formula (III), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (IV):

[0042]

[0043] The n in the structural formula (IV) is a natural number greater than or equal to 1; or, the polymer has the structural formula (V):

[0044]

[0045] In the structural formula (V), n is a natural number greater than or equal to 1; or,

[0046] The polymer has the structural formula (VI):

[0047]

[0048] In the structural formula (VI), n is a natural number greater than or equal to 1; or,

[0049] The polymer has the structural formula (VII),

[0050]

[0051] In the structural formula (VII), n is a natural number greater than or equal to 1; or

[0052] The polymer has the structural formula (VIII),

[0053]

[0054] In the structural formula (VIII), n is a natural number greater than or equal to 1.

[0055] The beneficial effects that can be achieved by the present invention are:

[0056] The present invention applies the free migration strategy to the synthesis of ring-containing polymers. Only by providing heating conditions or light conditions, the initiator can generate free radicals to initiate the polymerization monomer non-conjugated diene compounds to undergo cyclopolymerization to form cyclopolymers. The entire reaction process is easy to operate, the reaction conditions are mild, no auxiliary additives such as catalysts need to be added, the polymerization cost is low, and the conversion rate of the polymerization monomers is high. The obtained polymer has a high degree of cyclization, a low impurity content, a high purity, and a stable structure.

[0057] The molecular weight of the polymer synthesized by the cyclopolymerization method based on free radical migration of the present invention can be as high as 60,000, the molecular weight distribution is narrow, it has certain hardness and temperature tolerance, and has excellent optical properties.

[0058] The present invention can obtain polymers containing different side groups by designing the mobile functional groups and electron-withdrawing groups of the polymerization monomers, so that the polymers exhibit different states and different properties to adapt to different application fields and application requirements. The present invention has potential application value and is expected to be used as glass-transparent and extremely pure plastics in the fields of medical, optical, packaging and electronic applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0060] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of the polymer obtained in Example 1 of the present invention.

[0061] Figure 2 This is a physical picture of the polymer obtained in Example 1 of the present invention.

[0062] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0063] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0064] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0065] In the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0066] The present invention provides a cyclopolymerization method based on free radical migration, comprising the following steps:

[0067] Mixing the polymerization monomer and the initiator, heating and reacting to obtain a polymer;

[0068] in,

[0069] The polymerizable monomer is a diene compound, which includes an electron-withdrawing group and a mobile functional group. The initiator includes a compound that can generate free radicals under light conditions and / or heat conditions.

[0070] The present invention applies the free migration strategy to the synthesis of ring-containing polymers. Only by providing heating conditions or light conditions, the initiator can generate free radicals to initiate the polymerization monomer non-conjugated diene compounds to undergo cyclopolymerization to form polymers, and the obtained polymers are cyclopolymers. The entire reaction process is easy to operate, the reaction conditions are mild, no auxiliary additives such as catalysts need to be added, the polymerization cost is low, and the conversion rate of the polymerization monomers is high, the degree of cyclization is high, and the obtained polymers have high ring content, high purity, and stable structure.

[0071] The reaction mechanism of the present invention for obtaining a polymer by a cyclopolymerization method based on free radical migration is as follows: under heating conditions and / or light conditions, an initiator generates free radicals, and performs addition reaction with a non-conjugated diene compound of a polymerization monomer to form an alkyl free radical, and then the free radical reacts with a mobile functional group in the polymerization monomer to promote the functional group to migrate to a carbon atom at the far end and obtain another new free radical, and the free radical continues to repeat the above reaction process with another molecule of polymerization monomer, and performs polymerization reaction by utilizing a free migration strategy to finally obtain a polymer, which is a cyclopolymer.

[0072] The present invention provides an embodiment here to explain the reaction mechanism of the above-mentioned cyclopolymerization method based on free radical migration. However, it should be noted that the following embodiment is only one of the embodiments of the technical solution of the present invention and does not constitute a limitation to the technical solution of the present invention.

[0073] In this embodiment, the polymerizable monomer is monomer a, the mobile group in monomer a is -CN, and the electron withdrawing group is R 1 , and R is used as an initiator. The cyclopolymerization reaction process based on free radical migration is as follows:

[0074]

[0075] First, under the action of initiator R, it reacts with monomer a to form an active secondary alkyl radical b. Radical b undergoes tandem cyclization with another olefin unit in the molecule to generate radical c. Due to the presence of an unsaturated bond in the mobile functional group -CN, a bridged cyclic imine radical d is formed, which then triggers the breakage of the CC bond and the migration of the cyanide group, and finally forms an alkyl radical e. Radical e reacts with another molecule of monomer to form a monomer radical, which repeats the above reaction process again to finally form a polymer, which is a cyclized polymer.

[0076] In some embodiments, the polymerizable monomer comprises the following general structure: R 1 including electron withdrawing groups or mobile functional groups, and / or, R 2 Including electron-withdrawing groups or mobile functional groups. It should be noted that when R 1 is an electron-withdrawing group, R 2 is a mobile functional group. 1 is a mobile functional group, R 2 It is an electron-withdrawing group, so that the polymerized monomer contains both a mobile functional group and an electron-withdrawing group.

[0077] In some embodiments, the electron withdrawing groups in the polymerized monomers include -CN, -F, -Cl, -COOR 3 、-SO 2 Ph, -NO 2 , Etc. Among them, -COOR 3 R 3 Including fatty chains. Under the action of initiators, the above types of electron-withdrawing groups can promote the migration of mobile functional groups, causing them to migrate to the carbon atom at the far end, providing a polymerization reaction site for the next polymerization monomer.

[0078] In some embodiments, the mobile functional group in the polymerizable monomer includes an unsaturated functional group or a heteroatom. The unsaturated functional group includes a cyano group, an aryl group, a heteroaryl group, an oxime group, an alkenyl group, an alkynyl group or a carbonyl group, and the heteroatom includes a halogen atom, silicon or boron, etc. The mobile functional groups of the above types can undergo a migration reaction under the induction of free radicals and migrate to the carbon atom at the far end, so that the initiator can continuously introduce new polymerizable monomers, and finally complete the polymerization reaction to obtain a polymer.

[0079] The present invention does not limit the type of initiator. In some embodiments, the initiator includes at least one of an organic peroxide and an azo compound. The above types of initiators can generate free radicals under light conditions and / or heat conditions, react with polymerizable monomers to obtain alkyl free radicals, and generate a new free radical center to promote the migration of mobile functional groups in polymerizable monomers. New polymerizable monomers are continuously introduced using the strategy of free radical rearrangement reaction to finally obtain a polymer.

[0080] In some embodiments, the organic peroxide includes at least one of acyl peroxide, hydrogen peroxide, dialkyl peroxide, ester peroxide, ketone peroxide, and dicarbonate peroxide.

[0081] In some embodiments, the azo compound includes at least one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovaleronitrile, azobiscyclohexylcarbonitrile, and dimethyl azobisisobutyrate.

[0082] In some embodiments, the acyl peroxide includes at least one of benzoyl peroxide and lauroyl peroxide.

[0083] In some embodiments, the hydroperoxide includes at least one of cumene hydroperoxide and tert-butyl hydroperoxide.

[0084] In some embodiments, the dialkyl peroxide includes at least one of di-tert-butyl peroxide and dicumyl peroxide.

[0085] In some embodiments, the ester peroxide includes at least one of tert-butyl perbenzoate and tert-butyl pervalerate.

[0086] In some embodiments, the ketone peroxide includes at least one of methyl ethyl ketone peroxide and cyclohexanone peroxide.

[0087] In some embodiments, the dicarbonate peroxide includes at least one of diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate.

[0088] The above types of initiators can generate free radicals at relatively low temperatures, which in turn promote the migration of the mobile functional groups of the polymerization monomers, and continuously introduce new polymerization monomers to ultimately obtain polymers.

[0089] It should be noted that the initiator of the present invention is not limited to the types listed above, and the initiator of the present invention includes all compounds that can generate free radicals under light conditions and / or heat conditions. For example, when the initiator is a dithioester compound, the initiator can generate free radicals under light conditions, which in turn promotes the rearrangement reaction of the mobile functional groups of the polymerizable monomers, continuously introduces new polymerizable monomers, and finally obtains a polymer.

[0090] The present invention does not limit the molar ratio of the polymerization monomer to the initiator in the polymerization reaction. In some embodiments, the molar ratio of the polymerization monomer to the initiator is 100:(0.5-20). For example, the molar ratio can be any ratio in the range of 100:(1-20) such as 100:0.5, 100:1, 100:2, 100:4, 100:5, 100:6, 100:7, 100:8, 100:9, 100:10, 100:11, 100:12, 100:13, 100:14, 100:15, 100:16, 100:17, 100:18, 100:19, 100:20, etc. However, it is not limited to the above-listed ratio ranges.

[0091] In some embodiments, the temperature of the heating reaction is above 60°C, for example, the heating temperature can be 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 180°C, 200°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C, etc., which are reaction temperatures above 60°C. The present invention can induce the initiator to generate free radicals under relatively mild conditions, initiate polymerization of polymerization monomers, and obtain polymers.

[0092] It should be noted that the temperature conditions listed above are only some embodiments of the present invention. The present invention does not limit the temperature of the heating reaction, and the temperature of the heating reaction can be adjusted according to the temperature at which the initiator generates free radicals.

[0093] In some embodiments, the heating reaction time is any reaction time of more than 1 hour, for example, the reaction time can be any time value of more than 1 hour such as 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 20 hours, 30 hours, 40 hours, 50 hours, etc. Under the above heating reaction time limit, it is beneficial to obtain a polymer with a higher conversion rate.

[0094] The present invention does not limit the reaction atmosphere of the cyclopolymerization reaction, and the conditions of the cyclopolymerization reaction are mild and simple. In some embodiments, the cyclopolymerization reaction can be carried out under air conditions, and in other embodiments, the cyclopolymerization reaction can also be carried out in a protective gas atmosphere, and the protective gas includes nitrogen or argon.

[0095] The present invention applies the strategy of free radical migration to the cyclopolymerization reaction. Only under heating conditions or light conditions, the initiator can generate free radicals to initiate the polymerization monomer to complete the cyclopolymerization reaction to form a polymer, and the obtained polymer is a cyclopolymer. The entire reaction is easy to operate, the reaction conditions are mild, and there is no need to add auxiliary additives such as catalysts. The cyclopolymerization cost is low, the polymerization monomer conversion rate is also high, and the obtained polymer has less impurity content, high purity, high molecular weight, relatively narrow molecular weight distribution, relatively stable structure, and certain hardness and temperature tolerance. In addition, in some embodiments, the polymer prepared by the present invention can also obtain a glass appearance.

[0096] It should be noted that the cyclopolymerization method based on free migration of the present invention does not require the addition of auxiliary additives such as catalysts. It can be understood that the cyclopolymerization method based on free migration of the present invention can complete the cyclopolymerization reaction to obtain a polymer even without the assistance of auxiliary additives such as catalysts, but it does not mean that auxiliary additives such as catalysts cannot be added to the cyclopolymerization method of the present invention.

[0097] For example, in some embodiments, in the step of mixing the polymerizable monomer and the initiator, the polymerizable monomer and the initiator may be dissolved and mixed with an organic solvent. The organic solvent may promote the dissolution of the polymerizable monomer and the initiator, so that they are mixed more evenly.

[0098] The present invention does not limit the reaction concentration of the polymerized monomer in the organic solvent. The greater the reaction concentration, the more conducive to the polymerization reaction. In some embodiments, the amount of the polymerized monomer added is (0.5-20) mmol / mL based on the volume mL of the organic solvent. The above content ratios of the organic solvent and the polymerized monomer are only some embodiments listed in the present invention and do not constitute a limitation on the technical solution of the present invention.

[0099] The present invention does not limit the type of organic solvent. In some embodiments, the organic solvent includes at least one of ethanol, acetonitrile, acetone, dimethyl sulfoxide, N,N-dimethylformamide, ethyl acetate, diethylene glycol, and ethylene glycol. The above organic solvents have good solubility for polymerization monomers and initiators, can promote more uniform mixing of polymerization monomers and initiators, and promote the cyclopolymerization reaction.

[0100] The present invention also provides a polymer prepared by the cyclopolymerization method based on free radical migration as described above.

[0101] The present invention does not limit the molecular weight of the prepared polymer. In some embodiments, the molecular weight of the polymer of the present invention is above 1000, and can even reach 60,000. For example, the molecular weight of the polymer is any molecular weight above 1000 such as 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 20000, 30000, 40000, 50000, 60000, etc. The present invention can control the molecular weight of the polymer by controlling the amount of polymerization monomer and initiator added and the temperature and time of the heating reaction to obtain a polymer with a large molecular weight span to meet different production needs. Moreover, because the entire polymerization process is easy to operate and the conditions are mild, the reaction conditions can be easily adjusted to obtain polymers of different molecular weights to meet production needs.

[0102] In some embodiments, the distribution width PDI of the polymer of the present invention is 1.10-5.00, the distribution width is narrow, and the physical properties of the polymer are relatively stable.

[0103] The conversion rate of the polymerized monomer is related to factors such as reaction temperature, reaction time, and the amount of initiator, and the conversion rate can be controlled by controlling the above conditions. In some embodiments, the conversion rate of the polymerized monomer of the present invention is 20%-95%, for example, it can be any conversion rate in the range of 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, etc.

[0104] In some embodiments, the polymers of the present invention have the following general structure:

[0105]

[0106] R in the general structural formula 1 is an electron-withdrawing group, R 2 is a mobile functional group; n is a natural number greater than or equal to 1, R 1 and R 2 Depends on the structure of the polymerized monomers.

[0107] In some embodiments, the polymer has structure (I):

[0108]

[0109] n in the structural formula (I) is a natural number greater than or equal to 1. The polymer of this embodiment is polymerized by a monomer in which both the mobile functional group and the electron withdrawing group are -CN, and the obtained polymer contains acrylonitrile structural units and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has high mechanical strength, while the presence of the cyclic structure makes the polymer have high hardness, and has an appearance and performance similar to that of organic glass, and has important application prospects in the application of organic glass.

[0110] In some embodiments, the polymer has the structural formula (II):

[0111]

[0112] n in the structural formula (II) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has high mechanical strength, and the presence of the cyclic structure makes the polymer have high hardness.

[0113] In some embodiments, the polymer has the structural formula (III):

[0114]

[0115] n in the structural formula (III) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has high mechanical strength, and the presence of the cyclic structure makes the polymer have high hardness.

[0116] In some embodiments, the polymer has the structural formula (IV):

[0117]

[0118] n in the structural formula (IV) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has high mechanical strength, and the presence of the cyclic structure makes the polymer have high hardness.

[0119] In some embodiments, the polymer has structural formula (V):

[0120]

[0121] n in the structural formula (V) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer have oil resistance, wear resistance and high mechanical strength, and the presence of the cyclic structure makes the polymer have high hardness.

[0122] In some embodiments, the polymer has structural formula (VI):

[0123]

[0124] n in the structural formula (VI) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has high mechanical strength, and the presence of the cyclic structure makes the polymer have high hardness.

[0125] In some embodiments, the polymer has structural formula (VII):

[0126]

[0127] n in the structural formula (VII) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has a high mechanical strength, and the presence of the cyclic structure makes the polymer have a high hardness.

[0128] In some embodiments, the polymer has structural formula (VIII):

[0129]

[0130] n in the structural formula (VIII) is a natural number greater than or equal to 1. The polymer of this embodiment has a structural unit of acrylonitrile and a cyclic structure. The presence of the acrylonitrile structure makes the polymer oil-resistant, wear-resistant and has a high mechanical strength, and the presence of the cyclic structure makes the polymer have a high hardness.

[0131] It should be noted that the polymers listed above are only some embodiments of the technical solution of the present invention and do not constitute a limitation to the technical solution of the present invention.

[0132] It should be noted that the present invention is not limited to the preparation methods of all types of polymerizable monomers mentioned above, and the monomers can be prepared by any preparation method known to those skilled in the art.

[0133] Here, the present invention provides a method for preparing a polymerizable monomer, but the preparation method cannot be regarded as a limitation to the technical solution of the present invention.

[0134] In some embodiments, the method for preparing the polymerized monomer comprises the following steps:

[0135] Step 1, weigh NaH (3.0 equiv.) in a two-necked bottle, seal and replace nitrogen three times, add tetrahydrofuran at 0°C, and stir for 30 min to obtain a reaction solution.

[0136] Step 2: slowly add the reaction mixture of step 1 (1.0equiv.), continue stirring at 0℃ for 0.5h~2h, then add (3.0equiv.). Among them, R 1 The group is an electron-withdrawing group, which can be -CN, -F, -Cl, -COOR 3 (R 3 is a fatty chain), -SO 2 Ph or -NO 2 wait; The X groups include -Cl, -Br and the like.

[0137] Step 3: Use thin layer chromatography to detect the reaction results. After the reaction is complete, use saturated NH 4 The reaction was quenched with Cl solution, then extracted with ethyl acetate to obtain the reaction product, and then purified by column chromatography.

[0138] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention, and are not used to limit the present invention.

[0139] Preparation of polymer monomer a

[0140] The preparation method of polymerizable monomer a in this embodiment comprises the following steps:

[0141] Step 1, weigh NaH (3.0 equiv.) in a two-necked bottle, seal and replace nitrogen three times, dissolve in tetrahydrofuran at 0°C, and stir for 30 min to obtain a reaction solution.

[0142] Step 2: slowly add the reaction mixture in step 1 (1.0equiv.), continue stirring at 0℃ for 0.5h~2h, then add (3.0equiv.).

[0143] Step 3: Use thin layer chromatography to detect the reaction results. After confirming that the reaction is complete, use saturated NH 4 The reaction was quenched with Cl solution, and then the reaction product was extracted with ethyl acetate, and then purified by column chromatography.

[0144] The polymerized monomer a prepared in this embodiment has the following structural formula: That is, the electron-withdrawing group in the polymerized monomer a is -CN, and the migratable functional group is -CN.

[0145] Examples 1 to 19

[0146] The cyclopolymerization method based on free radical migration of embodiments 1 to 19 comprises the following steps:

[0147] According to Table 1, 5 mmol of polymerization monomer a was placed in a pressure tube, and then an initiator was added. The nitrogen was replaced three times, and then heating reaction was carried out under a nitrogen atmosphere according to the reaction conditions in Table 1 to obtain a polymer.

[0148] Table 1

[0149]

[0150] Examples 20 to 26

[0151] Examples 20 to 26 refer to the preparation method of Example 1, except that the polymerization monomer structures used in Examples 20 to 26 are different, and the obtained polymer structures are different.

[0152] The structural formulas of the polymerization monomers used in Examples 1 to 26 and the structural formulas of the obtained polymers are specifically shown in Table 2.

[0153] Table 2 Monomer structure and polymer structure

[0154]

[0155] Performance Testing

[0156] 1. The monomer conversion rate (%) of polymer a in Examples 1 to 26, i.e., the yield of the obtained polymer, as well as the molecular weight and distribution width PDI of the obtained polymer were measured. The results are shown in Table 3.

[0157] 2. Taking the polymer prepared in Example 1 as an example, the polymer was characterized by hydrogen nuclear magnetic resonance spectrum to obtain the following Figure 1 The hydrogen spectrum shown in FIG. 1 shows the structure of the polymer of this embodiment.

[0158] 3. Taking the polymer prepared in Example 1 as an example, observing its appearance, the polymer of this example is amber, has a certain hardness, and has a glass appearance, and has application prospects in the field of organic glass.

[0159] Table 3 Properties of the polymers obtained in Examples 1 to 26

[0160]

[0161] It can be seen from Tables 2 and 3 that the polymers obtained by the cyclopolymerization method based on free radical migration of the present invention are of various types, have rich structures, and have diverse properties, can meet different production needs, have potential application value, and have a high polymerization monomer conversion rate. The molecular weight range of the obtained polymer is wide, the distribution width is narrow, and the structure of the polymer is relatively stable.

[0162] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A cyclopolymerization method based on free radical migration, characterized in that: The following steps are involved: Mixing the polymerization monomer and the initiator, heating and reacting to obtain a polymer; in, The polymerizable monomer is a diene compound, and the diene compound includes an electron-withdrawing group and a mobile functional group. The initiator includes a compound that can generate free radicals under light conditions and / or heat conditions.

2. The cyclopolymerization method based on free radical migration according to claim 1, characterized in that: The polymerizable monomer comprises the following general structural formula: R1 includes an electron withdrawing group or a mobile functional group, And / or, R2 includes an electron withdrawing group or a mobile functional group.

3. The cyclopolymerization method based on free radical migration according to claim 2, characterized in that: The electron withdrawing groups include -CN, -F, -Cl, -COOR3, -SO2Ph, -NO2, Wherein, R3 in the -COOR3 comprises a fatty chain; And / or, the migratable functional group in the polymerizable monomer includes an unsaturated functional group or a heteroatom, the unsaturated functional group includes a cyano group, an aryl group, a heteroaryl group, an oxime group, an alkenyl group, an alkynyl group or a carbonyl group, and the heteroatom includes a halogen atom, silicon or boron.

4. The cyclopolymerization method based on free radical migration according to claim 1, characterized in that: The initiator includes at least one of an organic peroxide and an azo compound.

5. The cyclopolymerization method based on free radical migration according to claim 4, characterized in that: The organic peroxide includes at least one of acyl peroxide, hydrogen peroxide, dialkyl peroxide, ester peroxide, ketone peroxide, and dicarbonate peroxide; And / or, the azo compound includes at least one of azobisisobutyronitrile, azobisisoheptanenitrile, azobisisovaleronitrile, azobiscyclohexylcarbonitrile and dimethyl azobisisobutyrate.

6. The cyclopolymerization method based on free radical migration according to claim 5, characterized in that: The acyl peroxide includes at least one of benzoyl peroxide and lauroyl peroxide; And / or, the hydroperoxide includes at least one of cumene hydroperoxide and tert-butyl hydroperoxide; And / or, the dialkyl peroxide includes at least one of di-tert-butyl peroxide and dicumyl peroxide; And / or, the ester peroxide includes at least one of tert-butyl perbenzoate and tert-butyl peroxyvalerate; And / or, the ketone peroxide includes at least one of methyl ethyl ketone peroxide and cyclohexanone peroxide; And / or, the dicarbonate peroxide includes at least one of diisopropyl peroxydicarbonate and dicyclohexyl peroxydicarbonate.

7. The cyclopolymerization method based on free radical migration according to claim 1, characterized in that: The molar ratio of the polymerization monomer to the initiator is 100:(0.5-20); And / or, the temperature range of the heating reaction is above 60°C; And / or, the heating reaction is carried out in a protective gas atmosphere or air, and the protective gas includes nitrogen or argon; And / or, in the step of mixing the polymerization monomer and the initiator, the polymerization monomer and the initiator can also be dissolved and mixed in an organic solvent, and the organic solvent includes at least one of ethanol, acetonitrile, acetone, dimethyl sulfoxide, N,N-dimethylformamide, ethyl acetate, diethylene glycol, and ethylene glycol.

8. A polymer prepared by the cyclopolymerization method based on free radical migration according to any one of claims 1 to 7.

9. The polymer according to claim 8, characterized in that The polymer has a molecular weight of more than 1000; and / or, the polymer has a distribution width PDI of 1.10-5.00; And / or, the conversion rate of the polymerization monomer is 20%-95%; And / or, the polymer has the following general structural formula: R1 in the general structural formula includes an electron-withdrawing functional group; R2 in the general structural formula includes a migratable group; In the general structural formula, n is a natural number greater than or equal to 1.

10. The polymer according to claim 9, characterized in that The polymer has the following structural formula (I): In the structural formula (I), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (II): In the structural formula (II), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (III): In the structural formula (III), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (IV): The n in the structural formula (IV) is a natural number greater than or equal to 1; or, the polymer has the structural formula (V): In the structural formula (V), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (VI): In the structural formula (VI), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (VII), In the structural formula (VII), n is a natural number greater than or equal to 1; or, the polymer has the structural formula (VIII), In the structural formula (VIII), n is a natural number greater than or equal to 1.

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