A hyperbranched carbon dioxide-based polycarbonate and a preparation method and application thereof

Abstract

The application belongs to the field of high polymer chemistry, and relates to a hyperbranched carbon dioxide-based polycarbonate as well as a preparation method and application thereof. The hyperbranched carbon dioxide-based polycarbonate is prepared by self-condensation polymerization of a monomer shown in formula I; in formula I, it is a three-arm structural unit derived from an initiator; and it is a carbon dioxide-based polycarbonate segment obtained by ring-opening addition polymerization of an epoxide and carbon dioxide. Compared with the prior art, the application has the following advantages: the application uses triethylborane catalyst and a mixture of TBD or DBU as a catalyst, efficiently catalyzes copolymerization of carbon dioxide and an epoxide monomer to prepare a hyperbranched carbon dioxide-based polycarbonate with a new structure, and improves the glass transition temperature and fat dissolving performance of the polymer.

Description

Technical Field

[0001] This invention belongs to the field of polymer chemistry, specifically relating to a hyperbranched carbon dioxide-based polycarbonate, its preparation method, and its applications. Background Technology

[0002] Hyperbranched polymers are typically made from AB x Prepared by monomer self-condensation polymerization. AB x The monomer molecule contains at least two B functional groups and one A functional group. The A and B groups must be able to react with each other. Thus, it can be gradually expanded to hyperbranched polyester with a large number of branched structures through continuous self-condensation.

[0003] Carbon dioxide-based polycarbonate is a fully biodegradable and environmentally friendly plastic synthesized from carbon dioxide and epoxides. It is completely biodegradable and therefore does not pollute the environment. It can be used in elastomers, coatings, synthetic leather, safety glass, surface coatings (resins, leather, etc.), shoe soles, photoresists, adhesives, magnetic adhesives, conveyor belts, and other fields. However, traditional polypropylene carbonate (PPC) has limitations in its application in engineering plastics and medical fields due to its near-room-temperature glass transition temperature and poor processing performance. Therefore, there is an urgent need to develop new carbon dioxide-based polycarbonate materials to expand its application areas. Summary of the Invention

[0004] The purpose of this invention is to provide a method for the preparation and application of hyperbranched carbon dioxide-based polycarbonate, in order to solve the problems of existing materials such as polypropylene carbonate having simple structures, low glass transition temperatures, and limited application range.

[0005] To achieve the above objectives, a first aspect of the present invention provides a hyperbranched carbon dioxide-based polycarbonate, said hyperbranched carbon dioxide-based polycarbonate being prepared by a self-condensation reaction of a monomer represented by Formula I;

[0006]

[0007] In Formula I, It is a three-arm structural unit derived from a self-initiating agent;

[0008] Carbon dioxide-based polycarbonate segments are obtained by ring-opening addition polymerization of epoxide and carbon dioxide.

[0009] A second aspect of the present invention provides a method for preparing the hyperbranched carbon dioxide-based polycarbonate, comprising the following steps:

[0010] Under polymerization conditions, epoxide, carbon dioxide, catalyst and initiator are brought into contact to react and obtain the hyperbranched carbon dioxide-based polycarbonate.

[0011] A third aspect of the present invention provides the application of the hyperbranched carbon dioxide-based polycarbonate in biodegradable plastics.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] This invention uses triethylborane catalyst and one or a mixture of TBD or DBU as catalysts to efficiently catalyze the copolymerization of carbon dioxide and epoxide monomers to prepare a novel hyperbranched carbon dioxide-based polycarbonate, which improves the glass transition temperature and lipophilic properties of the polymer.

[0014] Other features and advantages of the present invention will be described in detail in the following detailed description section. Detailed Implementation

[0015] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0016] To achieve the above objectives, a first aspect of the present invention provides a hyperbranched carbon dioxide-based polycarbonate, said hyperbranched carbon dioxide-based polycarbonate being prepared by a self-condensation reaction of a monomer represented by Formula I;

[0017]

[0018] In Formula I, It is a three-arm structural unit derived from a self-initiating agent;

[0019] Carbon dioxide-based polycarbonate segments are obtained by ring-opening addition polymerization of epoxide and carbon dioxide.

[0020] According to the present invention, preferably, the initiator is 2,2-dihydroxymethylbutyric acid.

[0021] According to the present invention, preferably, the carbon dioxide-based polycarbonate segment is as shown in Formula II:

[0022]

[0023] In Formula II, R1 and R2 are each independently at least one of H, C1-C10 alkyl, C1-C10 ester and C1-C10 ether, or R1 and R2 form a cycloalkenyl or cycloalkyl group, n is an integer from 50 to 2500, and m is an integer from 0 to 10.

[0024] According to the present invention, preferably, the epoxide is selected from at least one of propylene oxide, ethylene oxide, epichlorohydrin glycidyl ether, glycidyl ester, 1,2-epoxybutane, 2,3-epoxybutane, epioxycyclopentane, epioxycyclohexane, 3,4-epoxy-1-cyclohexene, and epioxycyclooctane.

[0025] According to a specific embodiment of the present invention, when the epoxide is propylene oxide, the structural schematic formula of the obtained hyperbranched carbon dioxide-based polycarbonate is as follows:

[0026]

[0027] In the formula, n is an integer from 50 to 2500, and m is an integer from 0 to 10.

[0028] According to the present invention, preferably, the hyperbranched carbon dioxide-based polycarbonate has a number average molecular weight of 5,000 to 250,000 g / mol, more preferably 10,000 to 130,000 g / mol, and a molecular weight distribution index of 1.0 to 1.60, more preferably 1.12 to 1.35.

[0029] A second aspect of the present invention provides a method for preparing the hyperbranched carbon dioxide-based polycarbonate, comprising the following steps:

[0030] Under polymerization conditions, epoxide, carbon dioxide, catalyst and initiator are brought into contact to react and obtain the hyperbranched carbon dioxide-based polycarbonate.

[0031] According to the present invention, preferably, the catalyst comprises a main catalyst and a co-catalyst.

[0032] According to the present invention, preferably, the main catalyst is triethylborane (TEB), or triethylborane (TEB) combined with TBD and / or DBU.

[0033] According to the present invention, preferably, the co-catalyst is an ammonium salt and / or a phosphate salt, and more preferably selected from at least one of ammonium bromide, ammonium chloride, ammonium azide, ammonium monoxide and EtPh3PBr.

[0034] According to the present invention, preferably, the molar ratio of the main catalyst to the co-catalyst is 1:(0.1 to 10), more preferably 1:(0.5 to 6).

[0035] According to the present invention, preferably, the molar ratio of the epoxide to the main catalyst is 100 to 50000:1, more preferably (500-5000):1; the molar ratio of the epoxide to the initiator is (100 to 2000):1, more preferably (500 to 1000):1.

[0036] According to the present invention, preferably, the polymerization conditions include: polymerization pressure of 0.1 to 6 MPa, reaction time of 1 to 72 h, and reaction temperature of 25 to 100 °C.

[0037] According to the present invention, preferably, after the contact reaction, a separation and purification step is further included, wherein the separation and purification step is at least one of the following: vacuuming to remove unreacted raw materials, heating to remove unreacted raw materials, dissolving the product with excess solvent, adding methanol to precipitate, and centrifuging and drying.

[0038] A third aspect of the present invention provides the application of the hyperbranched carbon dioxide-based polycarbonate in biodegradable plastics.

[0039] The present invention will be further described below with reference to the embodiments, but the scope of the present invention is not limited to these embodiments.

[0040] Example 1

[0041] Propylene oxide (0.4 mol, 23.232 g), 2,2-dimethylolbutyric acid (0.0004 mol, 0.0593 g), triethylborane (0.0004 mol, 0.0392 g), and tetrabutylammonium bromide (0.0004 mol, 0.1289 g) were added to a 250 mL autoclave. The reaction apparatus was sealed, and carbon dioxide was introduced and the pressure was adjusted to 2 MPa. The reaction temperature was adjusted to 50 °C, and the reaction was stirred for 24 h. After stirring, the pressure relief valve was opened to release unreacted carbon dioxide and recover unreacted propylene oxide. Tetrahydrofuran was then added to dissolve the polymerization product, followed by the addition of methanol to precipitate the product. The product was filtered, washed, and dried to obtain hyperbranched carbon dioxide-based polycarbonate. The number average molecular weight of the hyperbranched carbon dioxide-based polycarbonate was tested to be 123 kg / mol, and the molecular weight distribution was 1.24.

[0042] Example 2

[0043] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method of Example 1, except that propylene oxide was replaced with ethylene oxide, epichlorohydrin glycidyl ether, glycidyl ester, 1,2-epoxybutane, 2,3-epoxybutane, epicyclopentane, epicyclohexane, 3,4-epoxy-1-cyclohexene, and epicyclooctane. The number-average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 103 kg / mol, 98 kg / mol, 114 kg / mol, 74 kg / mol, 87 kg / mol, 73 kg / mol, 97 kg / mol, 92 kg / mol, and 105 kg / mol, with molecular weight distributions of 1.24, 1.13, 1.31, 1.27, 1.24, 1.43, 1.29, 1.19, and 1.25, respectively.

[0044] Example 3

[0045] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that the catalyst was replaced by TEB (0.0004 mol / TBD (0.0001 mol), TEB (0.0004 mol / DBU (0.0001 mol), TEB (0.0004 mol / TBD (0.00005 mol) / DBU (0.00005 mol)). The number average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 94 kg / mol and 103 kg / mol, respectively, and the molecular weight distributions were 1.19 and 1.27, respectively.

[0046] Example 4

[0047] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that tetrabutylammonium bromide was replaced with ammonium bromide, ammonium chloride, ammonium azide, ammonium phosphate, and phosphate salts. The number-average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 101 kg / mol, 97 kg / mol, 74 kg / mol, 106 kg / mol, and 99 kg / mol, with molecular weight distributions of 1.17, 1.23, 1.17, 1.22, and 1.19, respectively.

[0048] Example 5

[0049] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that the amount of triethylborane was adjusted from 0.0004 mol to 0.0008 mol and 0.000008 mol. The number-average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 117 kg / mol and 91 kg / mol, respectively, and the molecular weight distributions were 1.22 and 1.35, respectively.

[0050] Example 6

[0051] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that the polymerization pressure was adjusted from 2 MPa to 0.1 MPa and 6 MPa. The number-average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 123 kg / mol and 131 kg / mol, respectively, and the molecular weight distributions were 1.24 and 1.37, respectively.

[0052] Example 7

[0053] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that the polymerization reaction time was adjusted from 24 h to 1 h and 72 h. The number average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 21 kg / mol and 119 kg / mol, respectively, and the molecular weight distributions were 1.26 and 1.35, respectively.

[0054] Example 8

[0055] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that the polymerization temperature was adjusted from 50°C to 25°C and 100°C. The number-average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 51 kg / mol and 76 kg / mol, respectively, and the molecular weight distributions were 1.25 and 1.32, respectively.

[0056] Example 9

[0057] Hyperbranched carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that the amount of 2,2-dimethylolbutyric acid was adjusted from 0.0004 mol to 0.004 mol and 0.00013 mol. The number-average molecular weights of the hyperbranched carbon dioxide-based polycarbonate were tested to be 27 kg / mol and 115 kg / mol, respectively, and the molecular weight distributions were 1.18 and 1.32, respectively.

[0058] Comparative Example 1

[0059] Carbon dioxide-based polycarbonate was prepared according to the method in Example 1, except that 2,2-dimethylolbutyric acid was not added. The carbon dioxide-based polycarbonate was tested to have a number-average molecular weight of 43 kg / mol and a molecular weight distribution of 1.27.

[0060] Comparative Example 2

[0061] Carbon dioxide-based polycarbonate was prepared according to the method of Example 1, except that triethylborane was replaced with zinc porphyrin catalyst. The hyperbranched carbon dioxide-based polycarbonate was tested to have a number-average molecular weight of 69 kg / mol and a molecular weight distribution of 1.15.

[0062] Application examples

[0063] Standard for testing glass transition temperature. The glass transition temperature of materials is determined using differential scanning calorimetry (temperature change rate 10℃ / min).

[0064] The properties of the hyperbranched carbon dioxide-based polycarbonate obtained in Example 1 and the carbon dioxide-based polycarbonates obtained in Comparative Examples 1-3 were tested, and the results are shown in Table 1.

[0065] Table 1

[0066] Glass transition temperature (°C) Example 1 52 Comparative Example 1 41 Comparative Example 2 39

[0067] As can be seen from Table 1, compared with the carbon dioxide-based polycarbonates of Comparative Examples 1-2, the hyperbranched carbon dioxide-based polycarbonate obtained in Example 1 has a higher glass transition temperature, better processing performance, and broadens the application field of carbon dioxide-based polycarbonate.

[0068] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0069] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

Claims

1. A hyperbranched carbon dioxide-based polycarbonate, characterized in that, The hyperbranched carbon dioxide-based polycarbonate is prepared by the self-condensation reaction of the monomers shown in Formula I. Formula I In formula I, is a three-armed building block derived from an initiator; the initiator is 2,2-dimethylol butanoic acid; Carbon dioxide-based polycarbonate segments are obtained by ring-opening addition polymerization of epoxide and carbon dioxide.

2. The hyperbranched carbon dioxide-based polycarbonate according to claim 1, wherein, The carbon dioxide-based polycarbonate segment is shown in Formula II: Formula II In Formula II, R1 and R2 are each independently at least one of H, C1-C10 alkyl, C1-C10 ester and C1-C10 ether, or R1 and R2 form a cycloalkenyl or cycloalkyl group, n is an integer from 50 to 2500, and m is an integer from 0 to 10.

3. The hyperbranched carbon dioxide-based polycarbonate according to claim 2, wherein, The epoxide is selected from at least one of propylene oxide, ethylene oxide, epichlorohydrin glycidyl ether, glycidyl ester, 1,2-epoxybutane, 2,3-epoxybutane, epicyclopentane, epicyclohexane, 3,4-epoxy-1-cyclohexene, and epicyclooctane.

4. The hyperbranched carbon dioxide-based polycarbonate according to any one of claims 1-3, wherein, The hyperbranched carbon dioxide-based polycarbonate has a number-average molecular weight of 5,000 to 250,000 g / mol and a molecular weight distribution index of 1.0 to 1.

60.

5. The hyperbranched carbon dioxide-based polycarbonate according to claim 4, wherein, The hyperbranched carbon dioxide-based polycarbonate has a number-average molecular weight of 10,000-130,000 g / mol and a molecular weight distribution index of 1.12-1.

35.

6. The method for preparing hyperbranched carbon dioxide-based polycarbonate according to any one of claims 1-5, characterized in that, Includes the following steps: Under polymerization conditions, epoxide, carbon dioxide, catalyst and initiator are brought into contact to react and obtain the hyperbranched carbon dioxide-based polycarbonate.

7. The preparation method according to claim 6, wherein, The catalyst comprises a main catalyst and a co-catalyst; the main catalyst is triethylborane (TEB), or triethylborane (TEB) with TBD and / or DBU; The co-catalyst is an ammonium salt and / or a phosphate salt.

8. The preparation method according to claim 7, wherein, The cocatalyst is selected from at least one of ammonium bromide, ammonium chloride, ammonium azide, ammonium monoxide, and EtPh3PBr.

9. The preparation method according to claim 7, wherein, The molar ratio of the main catalyst to the co-catalyst is 1:(0.1~10).

10. The preparation method according to claim 9, wherein, The molar ratio of the main catalyst to the co-catalyst is 1:(0.5~6).

11. The preparation method according to claim 7, wherein, The molar ratio of the epoxide to the main catalyst is 100~50000:1; the molar ratio of the epoxide to the initiator is (100~2000):

1.

12. The preparation method according to claim 11, wherein, The molar ratio of the epoxide to the main catalyst is (500-5000):

1.

13. The preparation method according to claim 11, wherein, The molar ratio of the epoxide to the initiator is (500~1000):

1.

14. The preparation method according to claim 6, wherein, The polymerization conditions include: polymerization pressure of 0.1~6MPa, reaction time of 1~72h, and reaction temperature of 25~100℃.

15. The preparation method according to claim 6, wherein, After the contact reaction, the process also includes a separation and purification step, which includes at least one of the following steps: vacuuming to remove unreacted raw materials, heating to remove unreacted raw materials, dissolving the product with excess solvent, adding methanol to precipitate, and centrifuging and drying.

16. The use of the hyperbranched carbon dioxide-based polycarbonate according to any one of claims 1-5 or the hyperbranched carbon dioxide-based polycarbonate prepared by the preparation method according to any one of claims 6-15 in biodegradable plastics.

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