Preparation method of polybutyrolactam copolymer with adjustable melting point
By loading R groups on 2-pyrrolidone, a polybutyrolactam copolymer with adjustable melting point was prepared, which solved the thermal decomposition problem caused by the high melting point of polybutyrolactam, achieved improvement in stability and melt processing performance, and promoted the Its commercial application.
Patent Information
- Application Number
- CN202310759590.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-26
- Publication Date
- 2024-12-27
AI Technical Summary
The high melting point of polybutyracam leads to thermal decomposition during melt processing, limiting its mass production and commercial application. The existing modification methods cannot effectively reduce the melting point and maintain melting processing performance.
By loading different R groups on 2-pyrrolidone and reacting with butyrolactam as comonomers with adjustable melting point polybutyrolactam copolymer was prepared, and the melting point of the product was adjusted.
The prepared polybutyracam copolymer has good stability, adjustable melting point, and a molecular weight between 10,000-60,000. The melting point is 150-190°C under the preferred technical solution, which is suitable for melting processing and promotes commercial promotion and use.
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Abstract
Description
Technical Field
[0001] The present application relates to a nylon synthesis process, and in particular to a method for preparing a polybutyrolactam copolymer with adjustable melting point. Background Art
[0002] As one of the five major engineering plastics, polyamide is widely used in various fields. With the acceleration of the process of miniaturization of equipment, high performance of electronic and electrical equipment, and lightweight of mechanical equipment, higher requirements are placed on polyamide in all aspects. Polybutyrolactam (Polyamide 4PA4) is a polyamide with only 4 carbon atoms in its structural unit. It is currently the only polyamide that can be biodegraded and chemically recycled. It is mainly used in synthetic fibers, antistatic materials, mask base fabrics, and structural materials.
[0003] Compared with conventional polyamides, polybutyrolactam is a nylon with a high melting point, but its melting point is close to its thermal decomposition temperature, and thermal decomposition occurs during the melting process, which makes its synthesis and melt processing extremely difficult. This is also an important reason for the slow mass production and commercial promotion of polybutyrolactam.
[0004] At present, the research on reducing the melting point of polybutyrolactam mainly focuses on structural modification or processing modification. The structural modification mainly involves synthesizing block copolymers or segment and modification. These modifications cannot change the continuous repeating structural units of butyrolactam in the main molecular chain of polybutyrolactam, so the effect on the crystallization and melting point of polybutyrolactam is very small, and the obtained modified polybutyrolactam still does not have melt processing performance. In patent CN 113214470 B, the author added inert metal complexes during the synthesis process to reduce the melting point of polybutyrolactam, but due to the presence of a large amount of metal complexes, its application field is limited.
[0005] As the only biodegradable polyamide, polybutyrolactam has very broad application prospects in many fields. Therefore, the preparation of a polybutyrolactam with adjustable melting point is of great significance for its large-scale production and commercial application. Summary of the invention
[0006] In view of the above-mentioned shortcomings of the prior art, in order to solve the problems of the polybutyrolactam in the prior art being too high in melting point and decomposition during melt processing, the purpose of the present application is to provide a method for preparing a polybutyrolactam copolymer with adjustable melting point.
[0007] To achieve the above-mentioned object and other related objects, the present application provides a method for preparing a polybutyrolactam copolymer in a first aspect, characterized in that it comprises the following steps:
[0008] 1) Preparation of mixed monomers: mixing the pre-treated butyrolactam and the comonomer, and then mixing them evenly to obtain a first mixed monomer and a second mixed monomer; wherein the structural formula of the comonomer is as shown in Formula I:
[0009]
[0010] R1 to R6 are each independently selected from H, halogen, C 1-10 Alkyl, amino, C 1-10 Haloalkyl, C 1-10 Alkynyl, C 1-10 Alkoxy, carbonyl, or C 1-10 Hydroxyl; and at least one of R1 to R6 is not H;
[0011] 2) Preparation of mixed monomer ionic liquid: reacting the first mixed monomer with a catalyst to obtain a mixed monomer ionic liquid;
[0012] 3) Preparation of mixed monomer activation solution: reacting the second mixed monomer with an acylating agent to obtain a mixed monomer activation solution;
[0013] 4) Preparation of mixed polymerization liquid: mixing the mixed monomer ionic liquid with the mixed monomer activation liquid to obtain a mixed polymerization liquid;
[0014] 5) Polymerization of polybutyrolactam copolymer: reacting the mixed polymerization liquid to obtain a crude polybutyrolactam copolymer; and obtaining the polybutyrolactam copolymer after post-treatment.
[0015] The second aspect of the present application provides a polybutyrolactam copolymer prepared by the preparation method of the polybutyrolactam copolymer described in the first aspect.
[0016] Compared with the prior art, the beneficial effects of this application are:
[0017] 1. The present invention prepares a polybutyrolactam copolymer by loading different R groups on 2-pyrrolidone and using 2-pyrrolidone derivatives as comonomers, thereby achieving regulation of the melting point of the product polybutyrolactam copolymer.
[0018] 2. The molecular weight of the polybutyrolactam copolymer with adjustable melting point prepared by the present invention is between 10,000 and 60,000; the stability is good and the melting point is adjustable; the preferred technical solution is that the molecular weight of the prepared polybutyrolactam copolymer is 30,000-50,000 and the melting point is 150-190°C.
[0019] 3. The structure and performance of the polybutyrolactam copolymer with adjustable melting point prepared by the present invention can be adjusted according to application requirements, and can be melt-processed, which is more conducive to commercial promotion and use. DETAILED DESCRIPTION
[0020] In order to make the invention purpose, technical scheme and beneficial effect of the present application clearer, the present application is further described below in conjunction with the examples. It should be understood that the examples are only used to explain the present application and are not used to limit the scope of the application. The test methods used in the following examples are conventional methods unless otherwise specified, and those familiar with the technology can easily understand other advantages and effects of the present application from the contents disclosed in this description.
[0021] The inventor of the present application provides a method for preparing a polybutyrolactam copolymer with adjustable melting point, and completes the present application on this basis.
[0022] The first aspect of the present application provides a method for preparing a polybutyrolactam copolymer, comprising the following steps:
[0023] 1) Preparation of mixed monomers: mixing the pre-treated butyrolactam and the comonomer, and then mixing them evenly to obtain a first mixed monomer and a second mixed monomer; wherein the structural formula of the comonomer is as shown in Formula I:
[0024]
[0025] R1 to R6 are each independently selected from H, halogen, C 1-10 Alkyl, amino, C 1-10 Haloalkyl, C 1-10 Alkynyl, C 1-10 Alkoxy, carbonyl, or C 1-10 Hydroxyl; and at least one of R1 to R6 is not H;
[0026] 2) Preparation of mixed monomer ionic liquid: reacting the first mixed monomer with a catalyst to obtain a mixed monomer ionic liquid;
[0027] 3) Preparation of mixed monomer activation solution: reacting the second mixed monomer with an acylating agent to obtain a mixed monomer activation solution;
[0028] 4) Preparation of mixed polymerization liquid: mixing the mixed monomer ionic liquid with the mixed monomer activation liquid to obtain a mixed polymerization liquid;
[0029] 5) Polymerization of polybutyrolactam copolymer: reacting the mixed polymerization liquid to obtain a crude polybutyrolactam copolymer; and obtaining the polybutyrolactam copolymer after post-treatment.
[0030] In the preparation method provided in the present application, step 1) refers to the preparation of a mixed monomer: mixing the pre-treated butyrolactam and the comonomer, and then mixing them evenly to separate them into a first mixed monomer and a second mixed monomer; wherein the structural formula of the comonomer is shown in Formula I:
[0031]
[0032] R1 to R6 are each independently selected from H, halogen, C 1-10 Alkyl, amino, C 1-10 Haloalkyl, C 1-10 Alkynyl, C 1-10 Alkoxy, carbonyl, or C 1-10 and at least one of R1 to R6 is not H.
[0033] In some embodiments of the present application, when R1, R2, R3, R4, R5, and R6 are each independently selected from halogen, the halogen may be, for example, fluorine (F), chlorine (Cl), bromine (Br), iodine (I), astatine (At), and the like.
[0034] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from C 1-10 Alkyl, C 1-10 The alkyl group may be, for example, C 1-10 Methyl, C 1-10 Ethyl, C 1-10 Propyl, C 1-10 Butyl et al. Further, C 1-10 The alkyl group may be, for example, C 1-2 Alkyl, C 2-5 Alkyl, C 5-7 Alkyl or C 7-10 Alkyl, etc.
[0035] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from an amino group.
[0036] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from C 1-10 When alkyl halide, C 1-10 The haloalkyl group may be, for example, C 1-10 Fluorinated alkyl, C 1-10 Chloroalkyl, C 1-10 Bromoalkyl, C 1-10 Iodoalkyl, C 1-10 Astatine, etc. Further, C 1-10 The haloalkyl group may be, for example, C 1-10 Halogenated methyl, C 1-10 Halogenated ethyl, C 1-10 Halogenated propyl, C 1-10 Furthermore, C 1-10 The haloalkyl group may be, for example, C 1-2 Haloalkyl, C 2-5 Haloalkyl, C 5-7 Haloalkyl or C 7-10 Haloalkyl, etc.
[0037] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from C 1-10 When alkynyl, C 1-10 Alkynyl groups can be, for example, C 1-2 Alkynyl, C 2-5 Alkynyl, C 5-7 Alkynyl or C 7-10 Alkynyl, etc.
[0038] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from C 1-10 When alkoxy, C 1-10 The alkoxy group can be, for example, C 1-10 Methoxy, C 1-10 Ethoxy, C 1-10 Propoxy, or C 1-10 Butoxy, etc. Further, C 1-10 The alkoxy group can be, for example, C 1-2 Alkoxy, C 2-5 Alkoxy, C 5-7 Alkoxy or C 7-10 Alkoxy, etc.
[0039] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from a carbonyl group.
[0040] In some embodiments of the present application, R1, R2, R3, R4, R5, and R6 are each independently selected from C 1-10 When hydroxyl group, C 1-10 The hydroxyl group can be, for example, C 1-2 Hydroxyl, C 2-5 Hydroxyl, C 5-7 Hydroxyl or C 7-10 Hydroxyl, etc.
[0041] In a specific embodiment of the present application, the comonomer is selected from (S)-5-bromomethyl-2-pyrrolidone, 5-methyl-2-pyrrolidone, (R)-5-bromomethyl-2-pyrrolidone, (S)-(+)-5-hydroxymethyl-2-pyrrolidone, 5,5-dimethyl-2-pyrrolidone, 4,4-dimethyl-2-pyrrolidone, 2,5-pyrrolidinedione or α,α-dimethyl-β-methylsuccinimide.
[0042] In a specific embodiment of the present application, by loading different R groups on 2-pyrrolidone, the melting point of the product polybutyrolactam copolymer is regulated. Specifically, when R5 or R6 of 2-pyrrolidone is methyl and the remaining R groups are H, the comonomer is 5-methyl-2-pyrrolidone, and the comonomer is reacted with butyrolactam to prepare a polybutyrolactam copolymer with a melting point of 185°C. When R5 and R6 of 2-pyrrolidone are methyl and the remaining R groups are H, the comonomer is 5,5-dimethyl-2-pyrrolidone, and the comonomer is reacted with butyrolactam to prepare a polybutyrolactam copolymer with a melting point of 165°C. When R3 and R4 of 2-pyrrolidone are methyl and the remaining R groups are H, the comonomer is 4,4-dimethyl-2-pyrrolidone, and the comonomer is reacted with butyrolactam to prepare a polybutyrolactam copolymer with a melting point of 175°C.
[0043] In some embodiments of the present application, in step 1), the pretreatment refers to purifying and drying the butyrolactam and the comonomer, and the purity of the butyrolactam and the comonomer after purification is above 99.9%. The drying and purification steps in the pretreatment can be conventionally performed in a manner well known to those skilled in the art. In step 1), the mixing is performed under dry inert atmosphere conditions.
[0044] In some embodiments of the present application, in step 1), the molar ratio of butyrolactam to the comonomer is 100:5 to 2000; specifically, it can be 10:1 to 5; more specifically, it can be 10:1 to 2, 10:2 to 3, 10:3 to 4, or 10:4 to 5, etc. The inert atmosphere is selected from a combination of one or more of nitrogen, helium, neon, and argon. The first mixed monomer and the second mixed monomer have the same composition, both including butyrolactam and a comonomer, and the weight parts of the two can be adjusted according to experimental requirements. The weight parts of the two can be equal or unequal. For example, the weight ratio of the first mixed monomer to the second mixed monomer can be 1:1, or it can be 5:3, 2:1, 3:2, and other unequal situations.
[0045] In the preparation method provided in the present application, step 2) refers to the preparation of a mixed monomer ionic liquid: reacting a first mixed monomer with a catalyst to obtain a mixed monomer ionic liquid.
[0046] In some embodiments of the present application, in step 2), the molar ratio of the first mixed monomer to the catalyst is 100:1-15, specifically, 100:1-4, 100:4-5, 100:5-10, or 100:10-15, etc.
[0047] In some embodiments of the present application, in step 2), the reaction temperature is 30-100°C; specifically, it can be 30-60°C, 60-80°C, or 80-100°C, etc.; the reaction temperature is 0.5-1h, specifically, it can be 0.5-0.7h, 0.7-0.8h, or 0.8-1h, etc.
[0048] In some embodiments of the present application, in step 2), the catalyst includes a combination of one or more of an alkali metal, an inorganic base, and an organic base. In a preferred embodiment of the present application, the alkali metal includes a combination of one or more of sodium, potassium, calcium, and lithium; the inorganic base includes conventional inorganic bases such as sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, and lithium hydroxide; the organic base includes conventional organic bases such as potassium tert-butoxide, sodium tert-butoxide, sodium ethoxide, potassium ethoxide, tert-butyl lithium, urea, and thiourea.
[0049] In the preparation method provided in the present application, step 3) refers to the preparation of a mixed monomer activation solution: reacting the second mixed monomer with an acylating agent to obtain a mixed monomer activation solution.
[0050] In some embodiments of the present application, in step 3), the molar ratio of the second mixed monomer to the acylating agent is 100:1-20, specifically, 100:1-10, 100:1-10, 100:10-15, or 100:15-20, etc.
[0051] In some embodiments of the present application, step 3) is carried out under the protection of an inert gas, and the inert gas is selected from a combination of one or more of nitrogen, helium, neon, and argon.
[0052] In some embodiments of the present application, in step 3), the reaction temperature is 25-80°C, specifically, it can be 25-60°C, 60-70°C, 70-75°C, or 75-80°C, etc.; the reaction temperature is 0.5-3h, specifically, it can be 0.5-1h, 1-1.5h, 1.5-2h, or 2-3h, etc.
[0053] In some embodiments of the present application, in step 3), the acylating agent includes an acyl chloride and / or a diisocyanate. In a preferred embodiment of the present application, the acyl chloride includes a combination of one or more of benzoyl chloride, terephthaloyl chloride, valeryl chloride, oxalyl chloride, acetyl chloride, stearyl chloride, tetradecanoyl chloride and octyl chloride; the diisocyanate includes a combination of one or more of p-phenylene diisocyanate, m-phenylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and L-lysine diisocyanate.
[0054] In the preparation method provided in the present application, step 2) and step 3) separately prepare the mixed monomer ionic liquid and the mixed monomer activation liquid instead of directly mixing the mixed monomer, catalyst and acylating agent. This is because separate preparation is more controllable, while direct mixing will lead to faster polymerization and it is difficult to control the reaction process.
[0055] In the preparation method provided in the present application, step 4) refers to the preparation of a mixed polymerization liquid: a mixed monomer ionic liquid is mixed with a mixed monomer activation liquid to obtain a mixed polymerization liquid.
[0056] In some embodiments of the present application, in step 4), the mixing is performed under the protection of an inert gas, and the inert gas is selected from a combination of one or more of nitrogen, helium, neon, and argon.
[0057] In some embodiments of the present application, in step 4), the mass ratio of the mixed monomer ionic liquid to the mixed monomer activation liquid is 10:1-100; specifically, it can be 10:1-10, 10:10-20, 10:20-50 or 10:50-100, etc. In a preferred embodiment of the present application, the mass ratio of the mixed monomer ionic liquid to the mixed monomer activation liquid is 1:1.
[0058] In the preparation method provided in the present application, step 5) refers to the polymerization of the polybutyrolactam copolymer: reacting the mixed polymerization liquid to obtain a crude polybutyrolactam copolymer, and then obtaining the polybutyrolactam copolymer after post-treatment.
[0059] In some embodiments of the present application, in step 5), the reaction temperature is 40-150°C, specifically, it can be 40-60°C, 60-80°C, 80-90°C, or 90-150°C, etc.; the reaction time is 4-24h, specifically, it can be 4-6h, 6-8h, 8-10h, or 10-24h, etc.
[0060] In the preparation method provided by the present application, in step 5), post-treatment refers to soaking, stirring, filtering and drying the crude polybutyrolactam copolymer in water. In the post-treatment, the temperature of the water is 60-90°C; specifically, it can be 60-70°C, 70-80°C, 80-85°C or 85-90°C, etc. The stirring time is 8-12h, specifically, it can be 8-10h, 10-11h, or 11-12h, etc. Filtration refers to removing the aqueous solution of unreacted mixed monomers in the crude polybutyrolactam copolymer, and the filter pore size can be, for example, 5-10 microns. The drying temperature is 80-110°C, specifically, it can be 80-90°C, 90-100°C, or 100-110°C, etc.
[0061] The second aspect of the present application provides a polybutyrolactam copolymer, which is prepared by the preparation method of the polybutyrolactam copolymer described in the first aspect. The molecular weight of the polybutyrolactam copolymer provided by the present application is between 10,000 and 60,000; the stability is good, and the melting point is adjustable; the preferred technical solution is that the molecular weight of the prepared polybutyrolactam copolymer is 30,000-50,000, and the melting point is 150-190°C. Compared with the melting point of polybutyrolactam of 265°C, the melting point of the polybutyrolactam copolymer of the present application is lower, and its structure and performance can be adjusted according to application requirements, and melt processing can be performed, which is more conducive to commercial promotion and use.
[0062] Compared with the prior art, the beneficial effects of this application are:
[0063] 1. The present invention prepares a polybutyrolactam copolymer by loading different R groups on 2-pyrrolidone and using 2-pyrrolidone derivatives as comonomers, thereby achieving regulation of the melting point of the product polybutyrolactam copolymer and lowering the melting point of polybutyrolactam in the prior art.
[0064] 2. The molecular weight of the polybutyrolactam copolymer with adjustable melting point prepared by the present invention is between 10,000 and 60,000; the stability is good and the melting point is adjustable; the preferred technical solution is that the molecular weight of the prepared polybutyrolactam copolymer is 30,000-50,000 and the melting point is 150-190°C.
[0065] 3. The structure and performance of the polybutyrolactam copolymer with adjustable melting point prepared by the present invention can be adjusted according to application requirements, and can be melt-processed, which is more conducive to commercial promotion and use.
[0066] The present application is further described below by way of examples, but the scope of the present application is not limited thereby.
[0067] Example 1
[0068] (1) Pretreatment of butyrolactam and comonomer
[0069] The butyrolactam and 5-methyl-2-pyrrolidone (comonomer) are dried and purified to obtain butyrolactam and the comonomer with a purity of more than 99.9%.
[0070] (2) Preparation of mixed monomers
[0071] The butyrolactam purified in step (1) is mixed with 5-methyl-2-pyrrolidone (comonomer) at a molar ratio of 10:3 under the protection of an inert gas, stirred evenly, and then evenly divided into a first mixed monomer and a second mixed monomer.
[0072] (3) Preparation of mixed monomer ionic liquid
[0073] The first mixed monomer is added with potassium hydroxide under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to potassium hydroxide is 100:4, and stirred at 80° C. for 1 hour to obtain a mixed monomer ionic liquid.
[0074] (4) Preparation of mixed monomer activation solution
[0075] The second mixed monomer was added with benzoyl chloride under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to the benzoyl chloride was 100:1, and stirred at 60° C. for 1.5 hours to obtain a mixed monomer activation solution.
[0076] (5) Preparation of mixed polymer solution
[0077] Under inert protective atmosphere, the mixed monomer ionic liquid and the mixed monomer activation liquid are uniformly mixed at a mass ratio of 1:1 at room temperature.
[0078] (6) Polymerization of polybutyrolactam copolymer
[0079] Under inert protective atmosphere, the mixed polymer solution is reacted at 80° C. for 8 h to obtain a polybutyrolactam copolymer with adjustable melting point.
[0080] (7) Post-treatment of polybutyrolactam copolymer
[0081] The polybutyrolactam copolymer was immersed in 80°C water and stirred for 8 hours, filtered, and then dried at 80°C to obtain the polybutyrolactam copolymer. The white solid finally obtained was the polybutyrolactam copolymer with adjustable melting point. The molecular weight was about 45,000; the weight yield was 93% and the melting point was 185°C.
[0082] Example 2
[0083] (1) Pretreatment of butyrolactam and comonomer
[0084] The butyrolactam and 5,5-dimethyl-2-pyrrolidone (commonomer) are dried and purified to obtain butyrolactam and the comonomer with a purity of more than 99.9%.
[0085] (2) Preparation of mixed monomers
[0086] The butyrolactam purified in step (1) is mixed with 5,5-dimethyl-2-pyrrolidone (comonomer) at a molar ratio of 10:2 under the protection of an inert gas, and after being stirred evenly, the mixture is evenly divided into a first mixed monomer and a second mixed monomer.
[0087] (3) Preparation of mixed monomer ionic liquid
[0088] Under inert protective gas conditions, sodium hydroxide is added to the first mixed monomer, wherein the molar ratio of the mixed monomer to the sodium hydroxide is 100:5, and the mixture is stirred at 80° C. for 1 hour to obtain a mixed monomer ionic liquid.
[0089] (4) Preparation of mixed monomer activation solution
[0090] The second mixed monomer was added with benzoyl chloride under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to the benzoyl chloride was 100:1, and stirred at 60° C. for 1.5 hours to obtain a mixed monomer activation solution.
[0091] (5) Preparation of mixed polymer solution
[0092] Under inert protective atmosphere, the mixed monomer ionic liquid and the mixed monomer activation liquid are uniformly mixed at a mass ratio of 1:1 at room temperature.
[0093] (6) Polymerization of polybutyrolactam copolymer
[0094] Under inert protective atmosphere, the mixed polymer solution is reacted at 90° C. for 6 hours to obtain a polybutyrolactam copolymer with adjustable melting point.
[0095] (7) Post-treatment of polybutyrolactam copolymer
[0096] The polybutyrolactam copolymer was immersed in 80°C water and stirred for 8 hours, filtered, and then dried at 80°C to obtain the polybutyrolactam copolymer. The white solid finally obtained was the polybutyrolactam copolymer with adjustable melting point. The molecular weight was about 35,000; the weight yield was 92% and the melting point was 165°C.
[0097] Example 3
[0098] (1) Pretreatment of butyrolactam and comonomer
[0099] The butyrolactam and 4,4-dimethyl-2-pyrrolidone (commonomer) are dried and purified to obtain butyrolactam and the comonomer with a purity of more than 99.9%.
[0100] (2) Preparation of mixed monomers
[0101] The butyrolactam purified in step (1) is mixed with 4,4-dimethyl-2-pyrrolidone (comonomer) at a molar ratio of 10:3 under the protection of an inert gas, stirred evenly, and then evenly divided into a first mixed monomer and a second mixed monomer.
[0102] (3) Preparation of mixed monomer ionic liquid
[0103] The first mixed monomer is added with sodium hydroxide under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to the sodium hydroxide is 100:5, and stirred at 80° C. for 1 hour to obtain a mixed monomer ionic liquid.
[0104] (4) Preparation of mixed monomer activation solution
[0105] The second mixed monomer was added with benzoyl chloride under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to the benzoyl chloride was 100:1, and stirred at 60° C. for 1.5 hours to obtain a mixed monomer activation solution.
[0106] (5) Preparation of mixed polymer solution
[0107] Under inert protective atmosphere, the mixed monomer ionic liquid and the mixed monomer activation liquid are uniformly mixed at a mass ratio of 1:1 at room temperature.
[0108] (6) Polymerization of polybutyrolactam copolymer
[0109] Under inert protective atmosphere, the mixed polymer solution is reacted at 90° C. for 10 hours to obtain a polybutyrolactam copolymer with adjustable melting point.
[0110] (7) Post-treatment of polybutyrolactam copolymer
[0111] The polybutyrolactam copolymer was immersed in 80°C water and stirred for 8 hours, filtered, and then dried at 80°C to obtain the polybutyrolactam copolymer. The white solid finally obtained was the polybutyrolactam copolymer with adjustable melting point. The molecular weight was about 35,000; the weight yield was 91% and the melting point was 175°C.
[0112] Comparative Example 1
[0113] (1) Butyrolactam pretreatment
[0114] The butyrolactam is dried and purified to obtain butyrolactam with a purity of more than 99.9%.
[0115] (2) Preparation of butyrolactam ionic liquid
[0116] Under an inert protective atmosphere, sodium hydroxide is added to butyrolactam, wherein the molar ratio of butyrolactam to sodium hydroxide is 100:5, and the mixture is stirred at 80° C. for 1 hour to obtain a butyrolactam ionic liquid.
[0117] (4) Preparation of butyrolactam activation solution
[0118] Under an inert protective atmosphere, benzoyl chloride was added to butyrolactam, wherein the molar ratio of butyrolactam to benzoyl chloride was 100:1, and the mixture was stirred at 60°C for 1.5 hours to obtain a butyrolactam activation solution.
[0119] (5) Preparation of butyrolactam polymer solution
[0120] Under inert protective atmosphere, the butyrolactam ion liquid and the butyrolactam activation liquid are mixed uniformly at a mass ratio of 1:1 at room temperature.
[0121] (6) Polymerization of polybutyrolactam
[0122] Under inert protective atmosphere, the butyrolactam polymer solution is reacted at 65° C. for 10 hours to obtain polybutyrolactam with adjustable melting point.
[0123] (7) Post-treatment of polybutyrolactam
[0124] The polybutyrolactam was immersed in 80℃ water and stirred for 8h, filtered, and then dried at 80℃ to obtain the polybutyrolactam. The white solid finally obtained was the polybutyrolactam copolymer with adjustable melting point. The molecular weight was about 40000; the weight yield was 92% and the melting point was 265℃.
[0125] Comparative Example 2
[0126] (1) Pretreatment of butyrolactam and comonomer
[0127] The butyrolactam and 4,4-dimethyl-2-pyrrolidone (commonomer) are dried and purified to obtain butyrolactam and the comonomer with a purity of more than 99.9%.
[0128] (2) Preparation of mixed monomers
[0129] The butyrolactam purified in step (1) is mixed with 4,4-dimethyl-2-pyrrolidone (comonomer) at a molar ratio of 100:3 under the protection of an inert gas, stirred evenly, and then evenly divided into a first mixed monomer and a second mixed monomer.
[0130] (3) Preparation of mixed monomer ionic liquid
[0131] The first mixed monomer is added with sodium hydroxide under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to the sodium hydroxide is 100:5, and stirred at 80° C. for 1 hour to obtain a mixed monomer ionic liquid.
[0132] (4) Preparation of mixed monomer activation solution
[0133] The second mixed monomer was added with benzoyl chloride under an inert protective atmosphere, wherein the molar ratio of the mixed monomer to the benzoyl chloride was 100:1, and stirred at 60° C. for 1.5 hours to obtain a mixed monomer activation solution.
[0134] (5) Preparation of mixed polymer solution
[0135] Under inert protective atmosphere, the mixed monomer ionic liquid and the mixed monomer activation liquid are uniformly mixed at a mass ratio of 1:1 at room temperature.
[0136] (6) Polymerization of polybutyrolactam copolymer
[0137] Under inert protective atmosphere, the mixed polymer solution is reacted at 90° C. for 10 hours to obtain a polybutyrolactam copolymer with adjustable melting point.
[0138] (7) Post-treatment of polybutyrolactam copolymer
[0139] The polybutyrolactam copolymer was immersed in 80℃ water and stirred for 8h, filtered, and then dried at 80℃ to obtain the polybutyrolactam copolymer. The white solid finally obtained is the polybutyrolactam copolymer with adjustable melting point. The molecular weight is about 36000; the weight yield is 90% and the melting point is 260℃. The melting point decrease is not obvious, and melt processing is still difficult.
[0140] In summary, the present application prepares a polybutyrolactam copolymer by loading different R groups on 2-pyrrolidone and using 2-pyrrolidone derivatives as comonomers, thereby achieving the regulation of the melting point of the product polybutyrolactam copolymer. The molecular weight of the polybutyrolactam copolymer with adjustable melting point prepared in the present application is between 10,000 and 60,000; it has good stability and adjustable melting point; in the preferred technical solution, the molecular weight of the prepared polybutyrolactam copolymer is 30,000-50,000, and the melting point is 150-190°C. The structure and performance of the polybutyrolactam copolymer with adjustable melting point prepared in the present application can be adjusted according to application requirements, and melt processing can be performed, which is more conducive to commercial promotion and use.
[0141] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present application. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present application.
Claims
1. A method for preparing a polybutyrolactam copolymer, characterized in that: The following steps are involved: 1) Preparation of mixed monomers: mixing the pre-treated butyrolactam and the comonomer, and then mixing them evenly to obtain a first mixed monomer and a second mixed monomer; Wherein, the structural formula of the comonomer is shown in Formula I: R1 to R6 are each independently selected from H, halogen, C 1-10 Alkyl, amino, C 1-10 Haloalkyl, C 1-10 Alkynyl, C 1-10 Alkoxy, carbonyl, or C 1-10 Hydroxyl; and at least one of R1 to R6 is not H; 2) Preparation of mixed monomer ionic liquid: reacting the first mixed monomer with a catalyst to obtain a mixed monomer ionic liquid; 3) Preparation of mixed monomer activation solution: reacting the second mixed monomer with an acylating agent to obtain a mixed monomer activation solution; 4) Preparation of mixed polymerization liquid: mixing the mixed monomer ionic liquid with the mixed monomer activation liquid to obtain a mixed polymerization liquid; 5) Polymerization of polybutyrolactam copolymer: reacting the mixed polymerization liquid to obtain a crude polybutyrolactam copolymer; and obtaining the polybutyrolactam copolymer after post-treatment.
2. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 1), the pretreatment refers to purifying and drying the butyrolactam and the comonomer; the purity of the butyrolactam and the comonomer after purification is above 99.9%; And / or, in step 1), the mixing is carried out under dry inert atmosphere; And / or, in step 1), the comonomer is selected from (S)-5-bromomethyl-2-pyrrolidone, 5-methyl-2-pyrrolidone, (R)-5-bromomethyl-2-pyrrolidone, (S)-(+)-5-hydroxymethyl-2-pyrrolidone, 5,5-dimethyl-2-pyrrolidone, 4,4-dimethyl-2-pyrrolidone, 2,5-pyrrolidinedione or α,α-dimethyl-β-methylsuccinimide.
3. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 1), the molar ratio of butyrolactam to the comonomer is 100:5-2000.
4. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 2), the molar ratio of the first mixed monomer to the catalyst is 100:1 to 15; and / or, in step 2), the reaction temperature is 30 to 100° C., and the reaction time is 0.5 to 1 h; And / or, in step 2), the catalyst comprises a combination of one or more of an alkali metal, an inorganic base and an organic base; preferably, the alkali metal comprises a combination of one or more of sodium, potassium, calcium and lithium; the inorganic base comprises a combination of one or more of sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide and lithium hydroxide; the organic base comprises a combination of one or more of potassium tert-butoxide, sodium tert-butoxide, sodium ethoxide, potassium ethoxide, tert-butyl lithium, urea and thiourea.
5. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 3), the molar ratio of the second mixed monomer to the acylating agent is 100:1-20; And / or, in step 3), the reaction is carried out under the protection of an inert gas; and / or, in step 3), the reaction temperature is 25 to 80° C., and the reaction time is 0.5 to 3 h; And / or, in step 3), the acylating agent includes an acyl chloride and / or a diisocyanate; preferably, the acyl chloride includes a combination of one or more of benzoyl chloride, terephthaloyl chloride, valeryl chloride, oxalyl chloride, acetyl chloride, stearyl chloride, tetradecanoyl chloride and octyl chloride; the diisocyanate includes a combination of one or more of p-phenylene diisocyanate, m-phenylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and L-lysine diisocyanate.
6. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 4), the mixing is carried out under the protection of an inert gas; And / or, in step 4), the mass ratio of the mixed monomer ionic liquid to the mixed monomer activation liquid is 10:1-100.
7. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 5), the reaction temperature is 40 to 150° C., and the reaction time is 4 to 24 hours.
8. The method for preparing a polybutyrolactam copolymer according to claim 1, wherein In step 5), the post-treatment refers to soaking, stirring, filtering and drying the crude polybutyrolactam copolymer in water.
9. The method for preparing a polybutyrolactam copolymer according to claim 8, wherein: The water temperature is 60-90°C; the stirring time is 8-12h; and the drying temperature is 80-110°C.
10. A polybutyrolactam copolymer prepared by the method for preparing a polybutyrolactam copolymer according to any one of claims 1 to 9.