2,5-furandicarboxylic acid-based polyesters films, methods for their preparation and uses

Abstract

The application relates to the field of polyester films, in particular to a 2,5-furan dicarboxylic acid-based polyester film and a preparation method and application thereof, the preparation method comprising the following steps: melt-blowing 2,5-furan dicarboxylic acid-based polyester into a net and hot-pressing into a film. The application develops a technology of melt-blowing 2,5-furan dicarboxylic acid-based polyester into a net and then hot-pressing and bonding to prepare a novel polyester film. The method has good film-forming effect on FDCA polyester, avoids the disadvantages (for example, uneven film thickness, uneven film transparency and the like) of polyester biaxial stretching film preparation, and effectively solves the problems of high cost, difficult processing and easy degradation of the FDCA film.

Description

Technical Field

[0001] This invention relates to the field of polyester films, specifically to a 2,5-furandicarboxylic acid-based polyester film, its preparation method, and its applications. Background Technology

[0002] 2,5-Furfurandicarboxylic acid (FDCA) has a similar molecular structure to the traditional petroleum-based monomer terephthalic acid (PTA). Both are aromatic compounds with cyclic conjugated systems and contain two hydroxyl groups. They are extremely similar in physical and chemical properties. Furthermore, because the furan ring in FDCA is a heterocyclic structure, it is easily degraded by benzene rings in nature, making FDCA-based aliphatic polyesters one of the most popular FDCA-based polymers.

[0003] Although FDCA and PTA have very similar chemical structures, the furan ring is more rigid than the benzene ring. Therefore, FDCA polyesters possess superior mechanical and heat resistance properties, especially their excellent gas barrier properties, overcoming the limitations of traditional PTA polyester materials (such as polyethylene terephthalate, PET) in high-sealing packaging applications. FDCA polyesters (such as polyethylene furanate, PEF) are considered a perfect replacement for PTA polyesters in the future, with wide applicability in packaging materials, engineering plastics, coatings, and fibers. For example, PEF beverage bottles outperform PET beverage bottles in many aspects, most notably in preventing gas permeation. Furthermore, compared to PET film, PEF film is more effective at preventing oxygen permeation (11 times that of PET film of the same thickness), carbon dioxide permeation (4 times that of PET film of the same thickness), and water vapor permeation (2 times that of PET film of the same thickness). The polarity and asymmetry of the furan ring in the FDCA molecular structure make the chain more rigid, thereby reducing the fluidity of the chain segments and preventing the diffusion of small molecules. Furthermore, the dense packing of molecular chains in polymer structures becomes easier under the influence of crystallization or other factors, which also reduces the free volume, prevents the dissolution and diffusion of small molecules, and improves barrier properties.

[0004] However, compared with PTA polyester, FDCA polyester has greater tensile strength and Young's modulus, and has significant advantages in mechanical strength and thermal properties, but FDCA polyester has poorer ductility and stretching film-forming effect than PTA polyester. Summary of the Invention

[0005] To address the issues of high cost, difficult processing, and easy degradation of FDCA polyester films, which have better gas barrier properties than PTA polyesters, resulting in poorer toughness, ductility, and stretching film-forming effect, this invention provides a 2,5-furandicarboxylic acid-based polyester film, its preparation method, and its applications. The preparation method described in this invention has a good film-forming effect on FDCA polyester, enabling the preparation of FDCA polyester into film materials with excellent gas barrier properties.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for preparing a film from a 2,5-furandicarboxylic acid-based polyester, the method comprising:

[0007] 2,5-furandicarboxylic acid-based polyester is melt-blown into a web and then hot-pressed into a film.

[0008] A second aspect of the present invention provides a 2,5-furandicarboxylic acid-based polyester film prepared by the method of the present invention.

[0009] A third aspect of the present invention provides the application of the 2,5-furandicarboxylic acid-based polyester film of the present invention in gas barrier applications.

[0010] Through the above technical solution, this invention has developed a technique for preparing a novel polyester film by meltblowing 2,5-furandicarboxylic acid-based polyester into a web and then hot-pressing it. This method has a good film-forming effect on FDCA polyester, avoids the drawbacks of biaxially stretched polyester film forming (such as uneven film thickness and uneven film transparency), and effectively solves the problems of high cost, difficult processing, and easy degradation of FDCA film.

[0011] The 2,5-furandicarboxylic acid-based polyester film material of the present invention has excellent gas barrier properties and can be used for gas barrier applications.

[0012] Furthermore, the inventors of this invention have discovered that the method for preparing films using the 2,5-furandicarboxylic acid-based polyester described in this invention, by employing a copolyester of FDCA and PTA, can improve the toughness and ductility of the copolyester, enhance the melt-fiber forming and film-forming effects of FDCA, and reduce resin costs.

[0013] Furthermore, the inventors of this invention have discovered that the method for preparing films using the 2,5-furandicarboxylic acid-based polyester described in this invention, by adding the first additive and / or the second additive described in this invention, can improve the film-forming properties of FDCA polyester or copolyester and optimize the gas barrier properties of FDCA-based polyester films; the method for preparing films using the 2,5-furandicarboxylic acid-based polyester described in this invention, the first additive improves the crystallization properties of the film, and the second additive improves the polyester degradation during thermoforming. Detailed Implementation

[0014] 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.

[0015] The first aspect of this invention provides a method for preparing a film from a 2,5-furandicarboxylic acid-based polyester, the method comprising:

[0016] This invention develops a technique for preparing novel polyester films by melt-blowing 2,5-furandicarboxylic acid (FDCA) polyester into a web and then hot-pressing it into a film. This method has good film-forming effect on FDCA polyester and effectively solves the problems of high cost, difficult processing, and easy degradation of FDCA films. The prepared film material has excellent gas barrier properties and can be used for gas barrier applications.

[0017] The meltblown method uses a high-speed hot airflow to rapidly stretch and solidify freshly extruded polymer melt into fibers. In this invention, the meltblown web forming process includes the following steps: heating to melt the polymer material; the molten polymer material enters the nozzle through a spinning box; under the stretching action of the high-temperature and high-speed airflow, the molten polymer material forms fibers; the fibers condense on a receiving device (e.g., a mesh curtain) and self-adhere to form a nonwoven fabric.

[0018] In this invention, the conditions for meltblown web formation are relatively wide, as long as 2,5-furandicarboxylic acid-based polyester can be meltblown into fibers and formed into a web. According to a preferred embodiment of this invention, the meltblown web forming nozzle temperature is 160-250°C, for example, a range of any two values ​​of 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, or above, preferably 220-270°C, which is beneficial for improving gas barrier properties.

[0019] According to a preferred embodiment of the present invention, the screw extruder temperature is 200-280°C, for example, a range consisting of any two of the following values: 210°C, 220°C, 230°C, 200°C, 235°C, 245°C, 250°C, 260°C, 270°C, or more, preferably 170-220°C, which is beneficial for improving gas barrier properties.

[0020] According to a preferred embodiment of the present invention, the receiving distance from the nozzle to the receiving device is 15-50cm, for example, 15cm, 20cm, 25cm, 30cm, 35cm, 40cm, 45cm, 50cm or any two of the above values, preferably 20-35cm, which is beneficial to improve gas barrier properties.

[0021] According to a preferred embodiment of the present invention, the hot air velocity is 0.2-2m. 3 / min, such as 0.2m 3 / min, 0.4m 3 / min, 0.6m 3 / min, 0.8m 3 / min, 1.0m 3 / min, 1.2m 3 / min, 14m 3 / min, 1.6m 3 / min, 1.8m 3 / min, 2.0m 3 / min or any two of the above values, preferably 0.6-1.2m 3 / min, which helps to improve gas barrier properties.

[0022] According to a preferred embodiment of the present invention, the hot air temperature is 40-150°C, such as a range consisting of any two values ​​of 40°C, 60°C, 80°C, 100°C, 120°C, 140°C, 150°C, or above, preferably 60-140°C, which is beneficial to improving gas barrier properties.

[0023] In this invention, the hot pressing conditions can be selected over a wide range. According to a preferred embodiment of the invention, the hot pressing temperature is 80-220℃, for example, 90℃, 100℃, 110℃, 130℃, 150℃, 180℃, 190℃, 200℃, 210℃, preferably 150-200℃; the hot pressing pressure is 0.1-20MPa, preferably 1-10MPa, which is beneficial for improving gas barrier properties.

[0024] In this invention, the range of selectable forms of meltblown web is relatively wide. According to a preferred embodiment of this invention, meltblown web is formed into nonwoven web, nonwoven fabric, needle-punched fabric or spunlace fabric.

[0025] According to a preferred embodiment of the present invention, the nonwoven mesh has a thickness of 0.5-2.0 mm.

[0026] In this invention, the meltblown forming effect is controlled by adjusting meltblown process parameters such as metering pump, die head temperature, hot air volume and receiving distance. The fiber diameter formed by meltblown web has a wide range of selectable values. According to a preferred embodiment of this invention, the diameter of the meltblown fiber is 1-15 micrometers, preferably 2-15 micrometers.

[0027] In this invention, the inventors discovered that the method for preparing films using the 2,5-furandicarboxylic acid-based polyester described in this invention, by adding the first additive and / or the second additive described in this invention, can improve the film-forming properties of FDCA polyester or copolyester and optimize the gas barrier properties of FDCA-based polyester films. According to a preferred embodiment of this invention, the method for preparing films using the 2,5-furandicarboxylic acid-based polyester includes:

[0028] The 2,5-furandicarboxylic acid-based polyester composition is melt-blown into a web and hot-pressed into a film. The 2,5-furandicarboxylic acid-based polyester composition contains 2,5-furandicarboxylic acid-based polyester, a first additive, and / or a second additive. By weight, the composition comprises: 100 parts of 2,5-furandicarboxylic acid-based polyester, 0-5 parts of the first additive, and 0-5 parts of the second additive, wherein the weight parts of the first additive and the second additive are not both 0. The first additive is selected from one or more of inorganic nanomaterials and cellulose nanocrystals. The second additive is selected from one or more of epoxidized soybean oil, siloxane, dioctyl phthalate, and dibutyl phthalate.

[0029] In this invention, the size of the first additive can be selected from a wide range, which is illustrative but does not limit the scope of the invention. According to a preferred embodiment of the invention, the size of the first additive is 20-1000 nm.

[0030] In this invention, the range of inorganic materials that can be selected is relatively wide. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the inorganic material is selected from one or more of SiO2, TiO2, SnO2, CeO2 or calcium carbonate.

[0031] According to a preferred embodiment of the present invention, the first additive is cellulose nanocrystals.

[0032] In this invention, the first additive can be 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or any range of two of the above values.

[0033] In this invention, the second additive can be 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, or any range of two of the above values.

[0034] According to a preferred embodiment of the present invention, the composition comprises, by weight: 100 parts of 2,5-furandicarboxylic acid polyester, 0.1-2 parts of first additive, and 0.2-3 parts of second additive.

[0035] According to a preferred embodiment of the present invention, the 2,5-furandicarboxylic acid-based polyester comprises 1-100 mol% of 2,5-furandicarboxylic acid aliphatic diol ester units. Preferably, the 2,5-furandicarboxylic acid-based polyester comprises 10-95 mol% of 2,5-furandicarboxylic acid aliphatic diol ester units, for example, 50 mol%, 60 mol%, 65 mol%, 70 mol%, 75 mol%, 80 mol%, 85 mol%, or 90 mol%.

[0036] In this invention, a wide range of aliphatic diols can be selected. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the aliphatic diol is selected from one or more of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, and cyclohexanediol, preferably ethylene glycol.

[0037] According to a preferred embodiment of the present invention, the 2,5-furandicarboxylic acid-based polyester is a copolyester of 2,5-furandicarboxylic acid and terephthalic acid.

[0038] In this invention, when the 2,5-furandicarboxylic acid-based polyester is a copolyester of 2,5-furandicarboxylic acid and terephthalic acid, the content of 2,5-furandicarboxylic acid aliphatic diol ester units and terephthalic acid aliphatic diol ester units can be selected within a wide range. This is an illustrative example, but does not limit the scope of the invention. According to a preferred embodiment of the invention, the 2,5-furandicarboxylic acid-based polyester comprises 8-85 mol% of 2,5-furandicarboxylic acid aliphatic diol ester units and 15-92 mol% of terephthalic acid aliphatic diol ester units.

[0039] According to a preferred embodiment of the present invention, when the 2,5-furandicarboxylic acid-based polyester is a copolyester of 2,5-furandicarboxylic acid and terephthalic acid, the molar ratio of 2,5-furandicarboxylic acid aliphatic diol ester units to terephthalic acid aliphatic diol ester units is 1:0.2-10.

[0040] According to a preferred embodiment of the present invention, the aliphatic diol in the 2,5-furandicarboxylic acid aliphatic diol ester unit can be selected from a wide range of types. This is an illustrative example, but does not limit the scope of the present invention. According to a preferred embodiment of the present invention, the aliphatic diol is selected from one or more of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, and cyclohexanediol, preferably ethylene glycol.

[0041] According to a preferred embodiment of the present invention, the range of aliphatic diols in the terephthalic acid aliphatic diol ester unit is relatively wide. This is an illustrative example, but does not limit the scope of the present invention. According to a preferred embodiment of the present invention, the aliphatic diol is selected from one or more of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, and cyclohexanediol, preferably ethylene glycol.

[0042] According to a preferred embodiment of the present invention, the method for preparing a copolyester of 2,5-furandicarboxylic acid and terephthalic acid includes:

[0043] (1) In the presence of a catalyst, 2,5-furandicarboxylic acid, terephthalic acid and aliphatic diol were esterified under negative pressure.

[0044] (2) The product of step (1) is subjected to transesterification polycondensation reaction;

[0045] The catalyst is selected from one or more of triethylantimony, antimony oxide, antimony trioxide, antimony trichloride, tetraethyl titanate, tetrabutyl titanate, dibutyltin oxide, tin dioxide, diphenyltin oxide, magnesium oxide, calcium oxide, barium oxide, zirconium dioxide, tetra(dimethylamino)zirconium, zirconium acetylacetonate, and dicyclopentadiene zirconium chloride.

[0046] In this invention, the negative pressure in step (1) can be selected from a wide range. This is an illustrative example, but it does not limit the scope of this invention. According to a preferred embodiment of this invention, the negative pressure is 0 to -0.1 MPa, preferably -0.02 to -0.8 MPa.

[0047] In this invention, the conditions for the esterification reaction can be selected from a wide range, and conventional conditions in the art are all acceptable. According to a preferred embodiment of this invention, the temperature is 100-180℃, and the reaction time can be determined according to actual needs. Generally, the reaction time is 0.5-48h, preferably 2-12h.

[0048] In this invention, the amount of catalyst can be selected from a wide range. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the mass of the catalyst is 0.05-5.0 wt% of the total mass of the reactants, preferably 0.1-1 wt%.

[0049] In this invention, the conditions for the transesterification polycondensation reaction are available in a wide range, and conventional conditions in the art are all acceptable. According to a preferred embodiment of this invention, the temperature is 200-280°C, and the reaction time can be determined according to actual needs, ranging from 1 to 48 hours, preferably 2 to 12 hours, and more preferably 2 to 8 hours.

[0050] According to a preferred embodiment of the present invention, the transesterification polycondensation reaction is carried out under negative pressure conditions, preferably 0 to -0.1 MPa, and more preferably -0.02 to -0.5 MPa.

[0051] A second aspect of the present invention provides a 2,5-furandicarboxylic acid-based polyester film prepared by the method of the present invention.

[0052] In this invention, the thickness of the 2,5-furandicarboxylic acid-based polyester film can be selected from a wide range, which is illustrative but does not limit the scope of the invention. According to a preferred embodiment of the invention, the film thickness is 0.5-50 micrometers, preferably 5-30 micrometers, and more preferably 6-15 micrometers.

[0053] A third aspect of this invention provides the application of the 2,5-furandicarboxylic acid-based polyester film described herein in gas barrier applications. The 2,5-furandicarboxylic acid-based polyester film described herein exhibits excellent gas barrier properties when used for gas barrier applications.

[0054] In this invention, the range of gases that can be blocked is relatively wide. This is an illustrative example, but it does not limit the scope of the invention. According to a preferred embodiment of the invention, the 2,5-furandicarboxylic acid-based polyester film is used to block one or more of oxygen, carbon dioxide, and water vapor.

[0055] To further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and are not intended to limit the scope of the claims of the present invention.

[0056] In the context of this invention specification, including the following embodiments, when the vacuum degree reaches -0.1 MPa in the polycondensation reaction, an absolute pressure mercury vacuum gauge is used to measure the absolute pressure. In the following embodiments, the gas permeability test method is as follows: the vacuum degree is controlled between -0.02 and -0.8 MPa.

[0057] In the following embodiments, the CLASSIC 216 gas permeameter manufactured by Labthink was used to conduct gas permeability testing, which meets the national standard GB / T 1038-2000. Its principle is based on the pressure difference method for gas permeability testing.

[0058] Example 1

[0059] (1) Zirconium acetylacetonate and antimony trioxide in a molar ratio of 1 were used as catalysts, and the molar ratio of FDCA and PTA monomers was 1. They were copolymerized with ethylene glycol, and the molar number of ethylene glycol was 2.5 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 180°C, and the by-product water generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0060] (2) The product of step (1) was subjected to polycondensation reaction at 230°C under vacuum conditions (pressure of -0.3MPa) for 4 hours;

[0061] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 185℃, the maximum temperature of the screw is controlled at 245℃, the receiving distance is 30cm, and the 100℃ hot air is 0.8m away. 3 / min, fiber diameter 3-12 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0062] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 8 times, carbon dioxide permeability by 3 times, and water vapor permeability by 1.5 times.

[0063] Example 2

[0064] (1) Triethylantimony and dibutyltin oxide in a molar ratio of 1 were used as catalysts, and the molar ratio of FDCA and PTA monomers was 4. The catalysts were copolymerized with ethylene glycol, and the molar number of ethylene glycol was 2.5 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 170°C, and the water by-product generated was removed under vacuum conditions (pressure of -0.08MPa). The esterification reaction was maintained for 4 hours.

[0065] (2) The product of step (1) was subjected to polycondensation reaction at 225°C under vacuum conditions (pressure of -0.3MPa) for 4 hours;

[0066] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 175℃, the maximum temperature of the screw is controlled at 240℃, the receiving distance is 30cm, and the 80℃ hot air is 0.8m away. 3 / min, fiber diameter 2-10 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 175℃ and 10MPa hot roller extrusion.

[0067] The prepared film has a thickness of 10 μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 10 times, prevent carbon dioxide permeability by 4 times, and prevent water vapor permeability by 2.5 times.

[0068] Example 3

[0069] (1) Triethylantimony and dibutyltin oxide in a molar ratio of 1 were used as catalysts, and the molar ratio of FDCA and PTA monomers was 1. Butanediol was copolymerized with FDCA, and the molar number of FDCA was 2.0 times that of PTA. The catalyst mass accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 160℃, and the by-product water generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 3 hours.

[0070] (2) The product of step (1) was subjected to polycondensation reaction at 220°C under vacuum conditions (pressure of -0.2MPa) for 4 hours;

[0071] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 190℃, the maximum temperature of the screw is controlled at 245℃, the receiving distance is 35cm, and the 60℃ hot air is 0.6m away. 3 / min, fiber diameter 4-15 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0072] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 7 times, carbon dioxide permeability by 2.5 times, and water vapor permeability by 2.5 times.

[0073] Example 4

[0074] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA and PTA monomers was 1. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 3 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 170℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 3 hours.

[0075] (2) The product of step (1) was subjected to polycondensation reaction at 230°C under vacuum conditions (pressure of -0.15MPa) for 4 hours;

[0076] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 190℃, the maximum temperature of the screw is controlled at 245℃, the receiving distance is 30cm, and the 100℃ hot air is 1.0m away. 3 / min, fiber diameter 2-12 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 2MPa hot roller extrusion.

[0077] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 8.2 times, carbon dioxide permeability by 3.5 times, and water vapor permeability by 2.8 times.

[0078] Example 5

[0079] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 3 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0080] (2) The product of step (1) was subjected to polycondensation reaction at 235°C under vacuum conditions (pressure of -0.2MPa) for 4 hours.

[0081] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 180℃, the maximum temperature of the screw is controlled at 245℃, the receiving distance is 25cm, and the 100℃ hot air is 0.8m away. 3 / min, fiber diameter 2-15 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 185℃ and 1MPa hot roller.

[0082] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 7 times, carbon dioxide permeability by 2.5 times, and water vapor permeability by 1.6 times.

[0083] Example 6

[0084] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. Butanediol was copolymerized with FDCA, and the molar number of FDCA was 3 times that of PTA. The catalyst mass accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 170℃. The by-product water generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0085] (2) The product of step (1) was subjected to polycondensation reaction at 230°C under vacuum conditions (pressure of -0.25MPa) for 4 hours;

[0086] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 170℃, the maximum temperature of the screw is controlled at 230℃, the receiving distance is 25cm, and the 80℃ hot air is 0.6m away. 3 / min, fiber diameter 1-10 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 175℃ and 10MPa hot roller extrusion.

[0087] The prepared film has a thickness of 10 μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 6 times, carbon dioxide permeability by 2.5 times, and water vapor permeability by 2 times.

[0088] Example 7

[0089] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with hexanediol, and the molar number of hexanediol was 2.5 times that of FDCA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 160℃. The by-product water generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0090] (2) The product of step (1) was subjected to polycondensation reaction at 220°C under vacuum conditions (pressure of -0.25MPa) for 5 hours;

[0091] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 170℃, the maximum temperature of the screw is controlled at 230℃, the receiving distance is 25cm, and the 120℃ hot air is 0.8m away. 3 / min, fiber diameter 1-10 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 175℃ and 10MPa hot roller extrusion.

[0092] The prepared film has a thickness of 10 μm. Compared with pure PET film of the same thickness, the mixed polyester film can more effectively block gases; it can prevent oxygen permeability by 5 times, carbon dioxide permeability by 2 times, and water vapor permeability by 1.6 times.

[0093] Example 8

[0094] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with cyclohexanediethanol, and the molar number of cyclohexanediethanol was 2.0 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 180℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 5 hours.

[0095] (2) The product of step (1) was subjected to polycondensation reaction at 240°C under vacuum conditions (pressure of -0.25MPa) for 3 hours;

[0096] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 220℃, the maximum temperature of the screw is controlled at 260℃, the receiving distance is 35cm, and the 1.0m hot air at 140℃ is supplied. 3 / min, fiber diameter 5-15 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 220℃ and 0.5MPa hot roller extrusion.

[0097] The prepared film has a thickness of 15μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 6 times, carbon dioxide permeability by 3 times, and water vapor permeability by 2.4 times.

[0098] Example 9

[0099] The method according to Example 5 differs in that...

[0100] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 2.5 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃. The water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0101] (2) The product of step (1) was subjected to polycondensation reaction at 235°C under vacuum conditions (pressure of -0.2MPa) for 4 hours;

[0102] (3) The blended polyester prepared in step (2) was mixed with cellulose nanocrystals (20-50 nm in size), with the cellulose nanocrystals accounting for 2% of the polyester weight. The mixture was then granulated by twin-screw extrusion. The resulting blend was then melt-blown using a single-screw extruder. The meltblown head temperature was controlled at 180°C, the maximum screw temperature was controlled at 240°C, the receiving distance was 25 cm, and 80°C hot air was supplied at a distance of 0.8 m. 3 / min, fiber diameter 2-15 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 185℃ and 2MPa hot roller extrusion.

[0103] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; the oxygen permeability is increased by 9.8 times, the carbon dioxide permeability is increased by 3.7 times, and the water vapor permeability is increased by 2.7 times.

[0104] Example 10

[0105] The method according to Example 5 differs in that...

[0106] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 3.0 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0107] (2) The product of step (1) was subjected to polycondensation reaction at 235°C for 4 hours under vacuum conditions (pressure of -0.2MPa);

[0108] (3) The blended polyester prepared in step (2) was mixed with nano-silica (30-100 nm in size), with the nano-silica accounting for 2% of the polyester weight. The mixture was then granulated by twin-screw extrusion. The resulting blend was then melt-blown using a single screw extruder. The meltblown head temperature was controlled at 180°C, the maximum screw temperature was controlled at 240°C, the receiving distance was 25 cm, and 80°C hot air was supplied at a distance of 0.8 m. 3 / min fiber diameter 2-15 microns, meltblown web (thickness 1mm), then the blended polyester nonwoven fabric is formed into a film under 2MPa hot roller extrusion at 185℃.

[0109] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; the oxygen permeability is increased by 8.4 times, the carbon dioxide permeability is increased by 3.1 times, and the water vapor permeability is increased by 2.6 times.

[0110] Example 11

[0111] The method according to Example 5 differs in that...

[0112] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 3.0 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0113] (2) The product of step (1) was subjected to polycondensation reaction at 235°C for 4 hours under vacuum conditions (pressure of -0.2MPa);

[0114] (3) The blended polyester prepared in step (2) was mixed with nano-tin dioxide (10-60 nm in size), with the nano-tin dioxide accounting for 2% of the polyester weight. The mixture was then granulated by twin-screw extrusion. The resulting blend was then melt-blown using a single screw extruder. The meltblown head temperature was controlled at 180°C, the maximum screw temperature was controlled at 240°C, the receiving distance was 25 cm, and 100°C hot air was supplied at a distance of 0.8 m. 3 / min fiber diameter 2-15 microns, meltblown web (thickness 1mm), then the blended polyester nonwoven fabric is formed into a film under 2MPa hot roller extrusion at 185℃.

[0115] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; the oxygen permeability is increased by 8.5 times, the carbon dioxide permeability is increased by 3.4 times, and the water vapor permeability is increased by 2.0 times.

[0116] Example 12

[0117] The method according to Example 5 differs in that...

[0118] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 3.0 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0119] (2) The product of step (1) was subjected to polycondensation reaction at 235°C under vacuum conditions (pressure of -0.25MPa) for 4 hours.

[0120] (3) The blended polyester prepared in step (2) was mixed with nano-tin dioxide (10-60 nm in size) and epoxidized soybean oil, with nano-tin dioxide accounting for 1% of the polyester weight and epoxidized soybean oil accounting for 1% of the polyester weight. The mixture was then granulated by twin-screw extrusion. The prepared blend was then melt-blown using a single-screw extruder. The meltblown head temperature was controlled at 180°C, the maximum screw temperature was controlled at 230°C, the receiving distance was 20 cm, and the 100°C hot air was supplied at a distance of 0.8 m. 3 / min, fiber diameter 2-15 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0121] The prepared film has a thickness of 11 μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 12 times, carbon dioxide permeability by 4.5 times, and water vapor permeability by 3 times.

[0122] Example 13

[0123] The method according to Example 5 differs in that...

[0124] (1) Tetra(dimethylamino)zirconium was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 2.5 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃. The water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0125] (2) The product of step (1) was subjected to polycondensation reaction at 235°C for 4 hours under vacuum conditions (pressure of -0.25MPa);

[0126] (3) The blended polyester prepared in step (2) was mixed with nano-titanium dioxide (20-60 nm in size) and trimethoxypropane, with nano-titanium dioxide accounting for 1% of the polyester weight and trimethoxypropane accounting for 1% of the polyester weight. The mixture was then granulated by twin-screw extrusion. The prepared blend was then melt-blown using a single screw extruder. The meltblown head temperature was controlled at 180°C, the maximum screw temperature was controlled at 230°C, the receiving distance was 30 cm, and 1.0 m of 100°C hot air was supplied. 3 / min, fiber diameter 2-12 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0127] The prepared film has a thickness of 10 μm. Compared with pure PET film of the same thickness, the mixed polyester film can more effectively block gases; the oxygen permeability is increased by 10 times, the carbon dioxide permeability is increased by 3.8 times, and the water vapor permeability is increased by 3.5 times.

[0128] Example 14

[0129] The method according to Example 5 differs in that...

[0130] (1) Tetra(dimethylamino)zirconium was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 2.5 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃. The water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0131] (2) The product of step (1) was subjected to polycondensation reaction at 235°C for 4 hours under vacuum conditions (pressure of -0.2MPa);

[0132] (3) The blended polyester prepared in step (2) was mixed with nano-silica (20-60 nm in size) and dioctyl phthalate, with nano-silica accounting for 1% of the polyester weight and dioctyl phthalate accounting for 1% of the polyester weight. The mixture was then granulated by twin-screw extrusion. The prepared blend was then melt-blown using a single-screw extruder, with the meltblown head temperature controlled at 180°C, the maximum screw temperature controlled at 230°C, the receiving distance 30 cm, and 1.0 m of 100°C hot air. 3 / min, fiber diameter 2-12 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0133] The prepared film has a thickness of 10 μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 13 times, carbon dioxide permeability by 5.5 times, and water vapor permeability by 3.6 times.

[0134] Example 15

[0135] (1) Zirconium acetylacetonate and antimony trioxide in a molar ratio of 1 were used as catalysts, FDCA was used as a monomer, and copolymerized with ethylene glycol, with the molar number of ethylene glycol being 2.5 times the molar number of FDCA; the mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 160℃, and the by-product water generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0136] (2) The product of step (1) was subjected to polycondensation reaction at 230°C under vacuum conditions (pressure of -0.3MPa) for 4 hours;

[0137] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 185℃, the maximum temperature of the screw is controlled at 245℃, the receiving distance is 30cm, and the 80℃ hot air is 0.8m away. 3 / min, fiber diameter 2-10 micrometers, meltblown web (thickness 0.5mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0138] The prepared film has a thickness of 8μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 7 times, carbon dioxide permeability by 2.5 times, and water vapor permeability by 1.4 times.

[0139] Example 16

[0140] (1) Zirconium acetylacetonate and antimony trioxide in a molar ratio of 1 were used as catalysts, FDCA was used as a monomer, and copolymerized with ethylene glycol, with the molar amount of ethylene glycol being 3 times the molar amount of FDCA; the mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 160℃, and the by-product water generated was removed under vacuum conditions (pressure of -0.8MPa), and the esterification reaction was maintained for 6 hours;

[0141] (2) The product of step (1) was subjected to polycondensation reaction at 230°C under vacuum conditions (pressure of -0.3MPa) for 4 hours;

[0142] (3) The blended polyester prepared in step (2) is formed by single-screw meltblown molding. The temperature of the meltblown head is controlled at 185℃, the maximum temperature of the screw is controlled at 245℃, the receiving distance is 30cm, and the 80℃ hot air is 0.8m away. 3 / min, fiber diameter controlled at 3-12 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 180℃ and 5MPa hot roller.

[0143] The prepared film has a thickness of 10 μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 7.5 times, carbon dioxide permeability by 2.8 times, and water vapor permeability by 1.5 times.

[0144] Example 17

[0145] The difference compared to Example 5 is that,

[0146] (1) Dicyclopentadiene zirconium chloride was used as a catalyst. The molar ratio of FDCA to PTA monomers was 5. It was copolymerized with ethylene glycol, and the molar number of ethylene glycol was 3 times that of FDCA and PTA. The mass of the catalyst accounted for 0.5% of the total mass of the reaction raw materials. The esterification reaction was carried out at 175℃, and the water by-product generated was removed under vacuum conditions (pressure of -0.8MPa). The esterification reaction was maintained for 4 hours.

[0147] (2) The product of step (1) was subjected to polycondensation reaction at 235°C under vacuum conditions (pressure of -0.2MPa) for 4 hours.

[0148] (3) The blended polyester prepared in step (2) is mixed with epoxidized soybean oil, with the epoxidized soybean oil accounting for 2% of the polyester weight. The mixture is then melt-blown using a single screw extruder. The meltblown head temperature is controlled at 180℃, the maximum screw temperature is controlled at 245℃, the receiving distance is 25cm, and the 100℃ hot air is supplied at a distance of 0.8m. 3 / min, fiber diameter 2-15 micrometers, meltblown web (thickness 1mm), the blended polyester nonwoven fabric is then extruded into a film at 185℃ and 1MPa hot roller.

[0149] The prepared film has a thickness of 12μm. Compared with pure PET film of the same thickness, the hybrid polyester film can more effectively block gases; it can prevent oxygen permeability by 7.7 times, carbon dioxide permeability by 2.6 times, and water vapor permeability by 1.8 times.

[0150] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing a thin film from a 2,5-furandicarboxylic acid-based polyester, characterized in that, The method includes: 2,5-furandicarboxylic acid-based polyester is melt-blown into a web and then hot-pressed into a film.

2. The method according to claim 1, wherein, The conditions for meltblown web formation include: the nozzle temperature is 160-250℃, preferably 170-220℃; Preferably, The maximum temperature of the screw compressor is 200-280℃, preferably 220-270℃; and / or The distance from the nozzle to the receiving device is 15-50 cm, preferably 20-35 cm; and / or The hot air velocity is 0.2-2m. 3 / min, preferably 0.6-1.2m 3 / min; and / or The hot air temperature is 40-150℃, preferably 60-140℃; and / or The hot pressing conditions include: a hot pressing temperature of 80-220℃, preferably 150-200℃; and a hot pressing pressure of 0.1-20MPa, preferably 1-10MPa.

3. The method according to claim 1 or 2, wherein, The meltblown web is formed into a nonwoven web, nonwoven fabric, needle-punched fabric, or spunlace fabric; Preferably, the nonwoven mesh has a thickness of 0.5-2.0 mm; and / or The diameter of the meltblown fibers is 1-15 micrometers, preferably 2-15 micrometers.

4. The method according to any one of claims 1-3, wherein, The method includes: The 2,5-furan dicarboxylic acid-based polyester composition was melt-blown into a web and then hot-pressed into a film. The composition comprises, by weight, 100 parts of 2,5-furandicarboxylic acid polyester, 0-5 parts of first additive, and 0-5 parts of second additive, wherein the weight parts of the first additive and the second additive are not both 0. The first additive is selected from one or more of inorganic nanomaterials and cellulose nanocrystals, and the size of the first additive is 20-1000 nm; preferably, the inorganic material is selected from one or more of SiO2, TiO2, SnO2, CeO2 and calcium carbonate. The second additive is selected from one or more of epoxidized soybean oil, siloxane, dioctyl phthalate, and dibutyl phthalate.

5. The preparation method according to claim 4, wherein, The composition comprises, by weight, 100 parts of 2,5-furandicarboxylic acid polyester, 0.1-2 parts of first additive, and 0.2-3 parts of second additive.

6. The method according to any one of claims 1-5, wherein, The 2,5-furandicarboxylic acid-based polyester comprises 1-100 mol% of 2,5-furandicarboxylic acid aliphatic diol ester units, wherein the aliphatic diol is selected from one or more of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, and cyclohexanediethanol, preferably ethylene glycol.

7. The method according to any one of claims 1-6, wherein, The 2,5-furandicarboxylic acid-based polyester is a copolyester of 2,5-furandicarboxylic acid and terephthalic acid, comprising 8-85 mol% of 2,5-furandicarboxylic acid aliphatic diol ester units and 15-92 mol% of terephthalic acid aliphatic diol ester units. In the 2,5-furandicarboxylic acid aliphatic diol ester unit and the terephthalic acid aliphatic diol ester unit, the aliphatic diol is independently selected from one or more of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol and cyclohexanediethanol, preferably ethylene glycol.

8. The method according to claim 7, wherein, The preparation method of 2,5-furandicarboxylic acid and terephthalic acid copolyester includes: (1) In the presence of a catalyst, 2,5-furandicarboxylic acid, terephthalic acid and aliphatic diol were esterified under negative pressure. (2) The product of step (1) is subjected to transesterification polycondensation reaction; The catalyst is selected from one or more of triethylantimony, antimony oxide, antimony trioxide, antimony trichloride, tetraethyl titanate, tetrabutyl titanate, dibutyltin oxide, tin dioxide, diphenyltin oxide, magnesium oxide, calcium oxide, barium oxide, zirconium dioxide, tetra(dimethylamino)zirconium, zirconium acetylacetonate, and dicyclopentadiene zirconium chloride; Preferably, The amount of aliphatic diol used is 100-500% of the molar number of the diacid monomer, preferably 100-300%, more preferably 150%-200%; and / or In step (1), the negative pressure is 0 to -0.1 MPa, preferably -0.02 to -0.8 MPa; and / or The esterification reaction conditions include: a temperature of 100-180℃, a reaction time of 0.5-48 h, preferably 2-12 h; and / or The catalyst mass is 0.05-5 wt% of the total mass of the reactants, preferably 0.1-1 wt%; and / or In step (2), the transesterification polycondensation reaction conditions include: a temperature of 200-280℃ and a reaction time of 1-48h, preferably 2-12h.

9. The 2,5-furandicarboxylic acid-based polyester film prepared by the method according to any one of claims 1-8, preferably, has a film thickness of 0.5 micrometers to 50 micrometers.

10. The use of the 2,5-furandicarboxylic acid-based polyester film of claim 9 in gas barrier applications, preferably in the barrier applications of one or more of oxygen, carbon dioxide, and water vapor.