Method for upgrading polycaprolactone recovered

Abstract

The present application relates to a kind of polycaprolactone upgrading recovery method, belong to polymer chemistry technical field.The method provided by the present application is that polycaprolactone, diamine or amino alcohol, ruthenium catalyst are mixed in solvent, heated 1-80h one-pot method upgrading preparation polyester amide and polyamide polymer material in the temperature range of 80 ℃-240 ℃, the properties of the obtained polymer can be adjusted by changing the type and feeding ratio of diamine or amino alcohol, and the number average molecular weight is 1000-500,000.The present application uses waste polycaprolactone and commercial catalyst as raw material, reaction condition is mild, byproduct is only hydrogen, and the requirement to production equipment is low, in solving plastic pollution, high performance polymer can also be prepared, meet the principles of green, efficient and safe production.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer chemistry, and particularly relates to a method for upgrading and recycling polycaprolactone. BACKGROUND

[0002] Polyesters have been widely used in recent decades due to their excellent comprehensive performance and low price. Based on the national policy of protecting the environment, sustainable development, and building an environmentally friendly and resource-saving society, how to dispose of waste polyester products has become a problem to be solved. Recycling and reusing waste polyesters is a green and feasible direction.

[0003] Polyester amide is a substance with both ester bonds and amide bonds in the polymer main chain. It combines the excellent biocompatibility and biodegradability of polyester with the excellent thermal performance and mechanical performance of polyamide. Compared with pure polyester, polyester amide has a higher application range and value, and has more excellent mechanical properties, stronger corrosion resistance and thermal stability, and biocompatibility. At present, polyester amide is widely used in flame-retardant materials, aerospace equipment, medical equipment and other fields.

[0004] Polyamide is an early developed and widely used engineering plastic, which has excellent mechanical properties, wear resistance, heat resistance, electrical insulation, chemical resistance and solvent resistance, and is widely used in the fields of machinery industry, aerospace equipment, electronic instruments, chemical equipment, etc.

[0005] In the field of organic synthesis, a series of pincer-type transition metal complexes can catalyze the dehydrogenative coupling of alcohols to form esters, and the dehydrogenative coupling of alcohols and amines to form amides, which is a kind of green and efficient organic reaction, and the by-product is only H2. Among them, the PNN-Ru complex reported by Milstein's group has excellent reaction properties, and the complex has realized commercial application. It has been reported that the catalyst can be used to catalyze the dehydrogenative polymerization of diols and diamines to prepare polyamides, and the dehydrogenative polycondensation of long-chain diol compounds to form polyesters. These reports are all about preparing high molecular polymers from small molecule compounds. This project hopes to directly use waste polymer materials as raw materials to prepare high-performance polyester amide and polyamide materials while degrading. SUMMARY

[0006] The present application aims to provide a method for preparing polyester amide and / or polyamide by upgrading and recycling polycaprolactone: first, polycaprolactone is degraded into diol or amino alcohol oligomer containing amide groups by the amino group in diamine and amino alcohol, and then the degradation product is converted into polyester amide and polyamide material in situ under the action of a ruthenium catalyst.

[0007] In a first aspect, the present application provides a method for preparing polyester amide and / or polyamide, comprising the following steps:

[0008] In a solvent system, under a catalyst, polycaprolactone reacts with diamines of formula II to form polyester amides or polyamides of formula I with various proportions of amide bonds and ester bonds;

[0009]

[0010] wherein x, y are independently selected from any integer from 0 to 300, and z is any integer from 1 to 300;

[0011] When x = y = 0, the polymer of formula I is a polyamide, otherwise the polymer of formula I is a polyester amide;

[0012] R1 groups of formula I and formula II are any one of aliphatic alkyl with chain length from 2 to 30, cycloalkyl, heterocycloalkyl with 3 to 30, aromatic, heteroaromatic with 5 to 30.

[0013] Preferably, the polycaprolactone has a molecular weight of 1000 to 5 million.

[0014] Preferably, the catalyst is a Milstein ruthenium catalyst.

[0015] Preferably, the source of polycaprolactone includes degradable plastics, aged paints, and waste textiles, etc.

[0016] Preferably, the diamine compound of formula II is any one of 1,2-ethylenediamine, 1,3- propylenediamine, 1,4-butylenediamine, 1,5-pentylenediamine, 1,6-hexylenediamine, 1,7- heptylenediamine, 1,8-octylenediamine, 1,9-nonylenediamine, 1,10-decylenediamine, 1,11- undecylenediamine, 1,12-dodecylenediamine, 1,13-tridecylenediamine, 1,14-tetradecylenediamine, 1,15-pentadecylenediamine, 1,16-hexadecylenediamine, p-xylylenediamine, m- xylylenediamine, 2,5-furanylenediamine, 1,3-cyclohexylenediamine, 1,4-cyclohexylenediamine.

[0017] Preferably, the amount of catalyst is 0.5-5% of the molar amount of polycaprolactone repeating units.

[0018] Preferably, the solvent is at least one of n-hexane, cyclohexane, benzene, toluene, chlorobenzene, bromobenzene, p-xylene, m-xylene, o-xylene, anisole, mesitylene, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, diglyme, dimethylformamide, dimethyl sulfoxide.

[0019] Preferably, the reaction temperature is 80-240℃, and the reaction time is 1-80h.

[0020] Preferably, the molar ratio of polycaprolactone repeating units to diamines is (1-20):1.

[0021] In a second aspect, the present application provides a method for preparing polyester amide, which uses amino alcohol III instead of diamine II to polymerize with polycaprolactone to form polyester amide of formula IV.

[0022]

[0023] wherein h, k, m, n are any integer from 0 to 300;

[0024] The R2 group in formula III and formula IV is any one of aliphatic alkyl with chain length of 1-30, 3-30 cycloalkyl, heterocycloalkyl, 5-30 aryl, heteroaryl.

[0025] Preferably, the amino alcohol of formula III includes any one of ethanolamine, 3-amino-1-propanol, 5-amino-1-pentanol, 5-(methylamino)-1-pentanol, 5-(ethylamino)-1-pentanol, 1-(4-aminophenyl)-4-piperidinol, 6-amino-1-hexanol, 7-aminoheptanol, 1-(2-aminoethyl)cyclopentanol, 1-(3-aminopropyl)piperidin-4-ol, 2-amino-3-hydroxypyridine.

[0026] Preferably, the molar ratio of polycaprolactone repeating unit to the amino alcohol of formula III is (1-20):(1-20).

[0027] The present application has the following beneficial effects:

[0028] (1) The preparation method provided by the present application converts polycaprolactone into polyester amide and polyamide polymer by one-pot method, without the step-by-step operation of "high molecular-small molecular-high molecular", the product has high value, saves time, and the raw material polycaprolactone used in the present application is mainly applied to plastics, which is recycled for the synthesis of polyester amide and polyamide, saving cost and being environmentally friendly.

[0029] (2) The preparation method provided by the present application uses a commercialized ruthenium catalyst, which does not need a complex preparation process; the catalyst has high catalytic efficiency, only generates target polymer and hydrogen gas in the whole reaction process, the product separation and purification is simple, and has good industrial application prospect.

[0030] (3) The preparation method provided by the present application can adjust the polymer properties by adjusting the types of functional groups of diamines or amino alcohols and their feeding ratios with polycaprolactone; therefore, the present application can use waste polycaprolactone as raw material to synthesize polyester amide and polyamide high molecular materials with specific chemical properties, mechanical properties, thermodynamic properties and electrical properties according to the use requirements. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1NMR hydrogen spectrum of the product polyamide obtained in Example 1 of the present application;

[0032] Figure 2 NMR hydrogen spectrum of the product polyesteramide obtained in Example 4 of the present application. DETAILED DESCRIPTION

[0033] The present application will be further described by the following examples in conjunction with the accompanying drawings.

[0034] In a first aspect, the present application provides a polyesteramide and / or a polyamide preparation method, comprising the following steps:

[0035] In a solvent system, under a catalyst, polycaprolactone reacts with a diamine of formula II to form a polyesteramide and a polyamide of formula I with various proportions of amide bonds and ester bonds;

[0036]

[0037]

[0038] wherein x, y are independently selected from any integer from 0 to 300, and z is any integer from 1 to 300;

[0039] When x = y = 0, the polymer of formula I is a polyamide, otherwise the polymer of formula I is a polyesteramide;

[0040] The R1 group of formula I and formula II includes any one of aliphatic alkyl with a chain length of 2-30, cycloalkyl with a chain length of 3-30, heterocycloalkyl with a chain length of 3-30, aromatic group with a chain length of 5-30, and heteroaromatic group with a chain length of 5-30.

[0041] Specifically, the polycaprolactone has a molecular weight of 1000-500,000.

[0042] Specifically, the catalyst includes a ruthenium catalyst.

[0043] In some embodiments, the diamine compound of formula II is any one of 1,2-ethylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, 1,5-pentylenediamine, 1,6-hexylenediamine, 1,7-heptylenediamine, 1,8-octylenediamine, 1,9-nonylenediamine, 1,10-decylenediamine, 1,11-undecylenediamine, 1,12-dodecylenediamine, 1,13-tridecylenediamine, 1,14-tetradecylenediamine, 1,15-pentadecylenediamine, 1,16-hexadecylenediamine, p-xylylenediamine, m-xylylenediamine, 2,5-furanylenediamine, 1,3-cyclohexylenediamine, and 1,4-cyclohexylenediamine.

[0044] In some embodiments, the catalyst is used in an amount of 0.5-5% of the molar amount of the polycaprolactone repeating unit.

[0045] In some embodiments, the solvent is at least one of n-hexane, cyclohexane, benzene, toluene, chlorobenzene, bromobenzene, p-xylene, m-xylene, o-xylene, anisole, mesitylene, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, diglyme, dimethylformamide, dimethyl sulfoxide.

[0046] In some embodiments, the reaction temperature is 80-240℃, and the reaction time is 1-80h.

[0047] Specifically, the molar ratio of the polycaprolactone repeating unit to the diamine is (1-20):1.

[0048] In a second aspect, the embodiments of the present application provide a preparation method of polyester amide, which uses the amino alcohol III to replace the diamine II to polymerize with polycaprolactone to generate the polyester amide shown in formula IV.

[0049]

[0050]

[0051] wherein, h, k, m, n are any integer from 0 to 300;

[0052] The R2 group in formula III and formula IV is any one of an aliphatic alkyl group with a chain length of 1-30, a cycloalkyl group with a chain length of 3-30, a heterocycloalkyl group with a chain length of 3-30, an aromatic group with a chain length of 5-30, or a heteroaromatic group with a chain length of 5-30.

[0053] Preferably, the amino alcohol shown in formula III includes any one of ethanolamine, 3-amino-1-propanol, 5-amino-1-pentanol, 5-(methylamino)-1-pentanol, 5-(ethylamino)-1-pentanol, 1-(4-aminophenyl)-4-piperidinol, 6-amino-1-hexanol, 7-aminohexanol, 1-(2-aminoethyl)cyclopentanol, 1-(3-aminopropyl)piperidin-4-ol, 2-amino-3-hydroxypyridine.

[0054] Specifically, the molar ratio of the polycaprolactone repeating unit to the amino alcohol shown in formula III is (1-20):(1-20).

[0055] The reagents used in the embodiments of the present application are commercially available, the ruthenium catalyst is purchased from Jiangsu Xinnuo Catalyst Co., Ltd., and the polycaprolactone is purchased from Shanghai Maikelin Biochemical Technology Co., Ltd.

[0056] Embodiment 1

[0057] The embodiments 1 of the present application provide a preparation method of polyamide and polyester amide, which includes the following steps:

[0058] S1, in a nitrogen glove box, 114 mg of polycaprolactone (1.0 mmol), 116 mg of 1,6-hexanediamine (1.0 mmol), 15 mg of Ru catalyst (0.03 mmol) were weighed into a 25 mL Schlenk tube, the molar ratio of polycaprolactone to 1,6-hexanediamine was 1:1;

[0059] S2, 2 mL of toluene was added to the Schlenk tube in S1, after stirring and dissolving at room temperature, the tube was sealed, the glove box was transferred out, and the Schlenk tube was connected to a nitrogen balloon;

[0060] S3, heated at 120°C for 5h, and vacuum for 43h to promote polymerization, to obtain a crude product; the crude product was precipitated with methanol to obtain a polyester amide or polyamide polymer, which was separated by filtration and dried at 40°C under vacuum for 48h to obtain a dry polymer.

[0061] Examples 2-40 provide a method for preparing a polyester amide and a polyamide, which is different from Example 1 in that the molar ratio of the amount of polycaprolactone to the amine compound is different, the amine compound selected during the reaction process is different, the amount of catalyst used, the reaction temperature, the reaction time, and the selection of the solvent are different, as shown in Table 1:

[0062] Table 1 shows the differences between Examples 2-42 and Example 1

[0063]

[0064]

[0065]

[0066] The examples shown in Table 1 are preferred embodiments, and other amine compounds and various ratios of polycaprolactone and different conditions are also within the scope of the present application.

[0067] Property testing

[0068] The products of Example 1 and Example 4 were taken to verify their structures, and the product structure was determined by 1 H NMR, the product structure of Example 1 is shown in Figure 1 , and the product structure of Example 4 is shown in Figure 2 .

[0069] Referring to Figure 1For the polyamide high molecular polymer prepared in the embodiment 1 of the present application, peak 1 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with the secondary amine group in the amide bond; peak 2 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with the carbonyl carbon in the amide bond; peak 3 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with peak 2; and peak 4 and peak 5 are characteristic peaks corresponding to hydrogen atoms on the methylene group between the secondary amine groups, which proves that the polyamide high molecular polymer is successfully prepared by the preparation method provided in the present application.

[0070] Referring to Figure 2 , Figure 2 For the polyester amide high molecular polymer prepared in the embodiment 4 of the present application, peak 1 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with the secondary amine group in the amide bond; peak 2 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with the carbonyl in the amide bond; peak 3 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with O in C-O in the ester bond; and peak 4 is a characteristic peak corresponding to hydrogen atoms on the methylene group connected with the carbonyl carbon in the ester bond, which proves that the polyester amide high molecular polymer is successfully prepared by the preparation method provided in the present application.

[0071] Although the embodiments of the present application are described in detail above, it is obvious for those skilled in the art that various modifications and changes can be made to the embodiments. However, it should be understood that such modifications and changes all belong to the scope and spirit of the present application described in the claims. Moreover, the present application described herein can have other embodiments and can be implemented or realized in various ways.

Claims

1. A method for upgrading a poly-caprolactone recycle, characterized in that, The method comprises the following steps: In a solvent system, under the action of a ruthenium catalyst, polycaprolactone is reacted with a diamine of formula II at 80-150 DEG C for 1-80 h to form a polyester amide and / or a polyamide of formula I; ； ； Wherein, x, y are independently selected from any integer from 0 to 300, z is any integer from 1 to 300, and the number average molecular weight of polycaprolactone is 1000-5000000; When x=y=0, the polymer of formula I is a polyamide, otherwise the polymer of formula I is a polyester amide; The R1 group of formula I and formula II includes any one of aliphatic alkyl with carbon chain length of 2-30, cycloalkyl with carbon chain length of 3-30, heterocycloalkyl with carbon chain length of 3-30, aromatic group with carbon chain length of 5-30, and heteroaromatic group with carbon chain length of 5-30; the ruthenium catalyst is a commercial Milstein catalyst, and the amount of the ruthenium catalyst is 0.5-5% of the molar amount of the polycaprolactone repeating unit.

2. The method of claim 1, wherein, The diamine of formula II includes any one of 1,2-ethylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, 1,5-pentylenediamine, 1,6-hexylenediamine, 1,7-heptylenediamine, 1,8-octylenediamine, 1,9-nonylenediamine, 1,10-decylenediamine, 1,11-undecylenediamine, 1,12-dodecylenediamine, 1,13-tridecylenediamine, 1,14-tetradecylenediamine, 1,15-pentadecylenediamine, 1,16-hexadecylenediamine, p-xylylenediamine, m-xylylenediamine, 2,5-furanylenediamine, 1,3-cyclohexylenediamine, and 1,4-cyclohexylenediamine.

3. The method of claim 1, wherein, The solvent includes at least one of n-hexane, cyclohexane, benzene, toluene, chlorobenzene, bromobenzene, p-xylene, m-xylene, o-xylene, anisole, mesitylene, tetrahydrofuran, 1,2-dimethoxyethane, 1,4-dioxane, diglyme, dimethylformamide, and dimethyl sulfoxide.

4. The method of claim 1, wherein, The molar ratio of the polycaprolactone repeating unit to the diamine is (1-20):

1.

5. The method according to any one of claims 1 to 4, wherein An amino alcohol III is used instead of the diamine II to react with polycaprolactone to form a polyester amide of formula IV; ； ； Wherein, h, k, m, n are independently selected from any integer from 0 to 300; The R2 group in formula III and formula IV includes any one of aliphatic alkyl with carbon chain length of 1-30, cycloalkyl with carbon chain length of 3-30, heterocycloalkyl with carbon chain length of 3-30, aromatic group with carbon chain length of 5-30, and heteroaromatic group with carbon chain length of 5-30.

6. The method of claim 5, wherein, The amino alcohol of formula III includes any one of ethanolamine, 3-amino-1-propanol, 5-amino-1-pentanol, 5-(methylamino)-1-pentanol, 5-(ethylamino)-1-pentanol, 1-(4-aminophenyl)-4-piperidinol, 6-amino-1-hexanol, 7-aminohexanol, 1-(2-aminoethyl)cyclopentanol, 1-(3-aminopropyl)piperidin-4-ol, and 2-amino-3-hydroxypyridine.

7. The method of claim 6, wherein, The molar ratio of the polycaprolactone repeating unit to the amino alcohol of formula III is (1-20):(1-20).

8. The method of claim 1, wherein, The source of the polycaprolactone includes degradable plastics, aged coatings, and waste textiles.

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