Degradable film paper and preparation method thereof

Abstract

The invention belongs to the technical field of packaging film paper, and particularly relates to degradable film paper which comprises an aluminized paper layer, and the aluminized paper layer comprises a base material layer; the coating adhesive layers are respectively arranged on two surfaces of the base material layer and are formed by coating a solvent-free adhesive on the surface of the base material layer and curing the solvent-free adhesive; the barrier layer is arranged on the surface, far away from the base material layer, of the coating adhesive layer, and an aluminum oxide layer is formed on the surface, far away from the coating adhesive layer, of the barrier layer through a vacuum evaporation process; the peel strength of the aluminized paper layer is greater than or equal to 2.5 N / 15mm; the oxygen permeation rate in a 23 DEG C / 90% RH environment is less than or equal to 15 cm < 3 > / m < 2 >. 24h. 1atm; and the permeable rate in a 23 DEG C / 90% RH environment is less than or equal to 10g / m < 2 >. 24h. According to the degradable membrane paper provided by the invention, the aluminum-plated paper layer is formed by combining the base material layer and the barrier layer through the coating adhesive layer, all the layers are degradable environment-friendly materials, the overall degradation speed of the membrane paper can be effectively increased, environmental protection is facilitated, and the whole membrane paper has good peeling strength, oxygen permeation rate and water permeation rate.

Description

Technical Field

[0001] The present invention belongs to the technical field of packaging film paper, and particularly relates to a degradable film paper and a preparation method thereof. Background Art

[0002] In the context of the current global acceleration towards sustainability, seeking environmentally friendly packaging materials has become one of the core issues in the packaging industry. Traditional plastic packaging materials occupy a large share in the market due to their durability and easy processability, but the resulting environmental problems are becoming increasingly severe. Plastics are not easily degradable and can remain in the natural environment for hundreds of years, causing serious impacts on soil, water quality, and marine ecosystems.

[0003] With the increasing public environmental awareness and the strengthening of environmental protection regulations by governments of various countries, the market demand for environmentally friendly packaging materials shows a significant growth trend. Consumers, enterprises, and policy drivers aiming at environmental protection jointly provide impetus for the market growth of degradable packaging materials. Especially in the fields of retail, food packaging, and daily consumer goods, the application of degradable packaging materials is the most extensive; more and more brand owners have also turned to using environmentally friendly packaging materials in order to enhance their own image and market competitiveness to meet consumers' expectations for green environmental protection. Coupled with the fact that many countries have started to implement policies restricting or taxing plastics, manufacturers and retailers have to seek alternative environmentally friendly packaging solutions to actively respond to the global environmental protection movement.

[0004] In view of this, developing a new type of environmentally friendly packaging material and promoting its use has far-reaching significance for promoting the development of a green, low-carbon, and circular economy. Summary of the Invention

[0005] To solve the above problems, the invention purpose of the first aspect of the present application is to provide a degradable film paper, in which the aluminized paper layer is formed by combining a base material layer and a barrier layer through a coating adhesive layer. Not only are all layers made of degradable environmental protection materials, which can effectively improve the overall degradation speed of the film paper and is conducive to environmental protection, but also the overall film paper has good peel strength, oxygen permeability, and water permeability. In addition, the aluminized paper layer can be combined with a polylactic acid layer and a PBS layer, or with a PBS / PLA composite film layer through glue to form film papers with different structures. The raw materials of the polylactic acid layer, PBS layer, and PBS / PLA composite film layer are also degradable materials. Therefore, the formed film paper not only has a relatively high degradation rate, but also can further effectively optimize the overall peel strength, oxygen permeability, and water permeability of the film paper to meet the packaging requirements of different products.

[0006] The invention purpose of the second aspect of the present application is to provide a preparation method of a degradable film paper, which is compatible with existing soft packaging production lines and does not require additional equipment investment, thus effectively ensuring the low cost of film paper preparation.

[0007] To achieve the above object, the present invention provides the following technical solutions: The degradable film paper in the present invention includes an aluminized paper layer, and the aluminized paper layer includes: A base material layer; A coating adhesive layer, which is provided on both sides of the base material layer and is formed by curing a solvent-free adhesive coated on the surface of the base material layer; And a barrier layer, which is provided on the side of the coating adhesive layer away from the base material layer, and an alumina layer is formed on the side away from the coating adhesive layer by a vacuum evaporation process; And the peel strength of the aluminized paper layer ≥ 2.5 N / 15 mm; the oxygen transmission rate at 23°C / 90% RH environment ≤ 15 cm 3 / m 2 .24 h.1 atm; the water permeability at 23°C / 90% RH environment ≤ 10 g / m 2 .24 h.

[0008] Further, the barrier layer is a polylactic acid film layer, which is formed by mixing nano-alumina and polylactic acid in a mass percentage ratio of (1:99)-(10:90), and the thickness is 20 μm - 40 μm; the thickness of the alumina layer ≤ 0.5 μm.

[0009] Further, the polylactic acid is poly-L-lactic acid, which is formed by polycondensation or ring-opening polymerization of L-lactic acid and / or D-lactic acid with lactide as an intermediate, the mass percentage content of L-lactic acid > 90%, and the mass percentage content of D-lactic acid is 1%-10%.

[0010] Further, the polylactic acid is a copolymer-modified polylactic acid, which is formed by introducing a comonomer into a lactic acid unit for polymerization, and the comonomer is glycolic acid or caprolactone, and the mass percentage content < 20%; Or it is formed by adding 5%-10% of polybutylene adipate terephthalate to the lactic acid unit.

[0011] Further, the degradable film paper further includes: A polylactic acid layer, which is provided on one side of the aluminized paper layer; A PBS layer, which is provided on the other side of the aluminized paper layer; A first glue composite layer, which is provided between the polylactic acid layer and the aluminized paper layer; And a second glue composite layer, which is provided between the PBS layer and the aluminized paper layer.

[0012] Further, the degradable film paper further includes: A PBS / PLA composite film layer, which is provided on both sides of the aluminized paper layer; And a third glue composite layer, which is disposed between the aluminized paper layer and the PBS / PLA composite film layer.

[0013] Further, the PBS / PLA composite film layer is composed of 60%-80% by mass of PBS and 20%-40% by mass of PLA, and has a thickness of 10μm - 20μm.

[0014] Further, the coating glue layer, the first glue composite layer, the second glue composite layer and the third glue composite layer are all formed by curing a polyurethane adhesive coated on the surface of the base material layer, and the solid content of the polyurethane adhesive ≥ 99%.

[0015] Further, the peel strength of the degradable film paper is 10 N / 15mm - 15N / 15mm; the oxygen transmission rate at 23℃ / 90% RH environment ≤ 5cm 3 / m 2 .24h.1atm; the water permeability at 23℃ / 90% RH environment ≤ 1g / m 2 .24h.

[0016] The preparation method of the degradable film paper in the present invention includes the following steps: S10. Prepare the aluminized paper layer; S20. Prepare the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer; S30. Use a precision coating device to coat a solvent-free adhesive on the surface of the aluminized paper layer, then stack the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer on the glue layer, roll and compound, cure and slit to obtain the degradable film paper; wherein, In the step of preparing the aluminized paper layer, it includes the following steps: S11. Corona-treat the surface of the base material layer; S12. The barrier layer is extruded by a screw extruder in a three-stage temperature control manner, and an alumina layer is formed on the surface of the barrier layer by a vacuum evaporation coating process; S13. Use a precision coating device to coat a solvent-free adhesive on the surface of the base material layer, roll and compound it with the non-aluminized side of the barrier layer, and after curing, obtain the aluminized paper layer.

[0017] Based on the above technical solutions, the present invention has the following technical effects: 1. For the degradable film paper provided by the present invention, the aluminized paper layer is formed by combining the base material layer and the barrier layer through the coating glue layer. Not only are all layers made of degradable environmental protection materials, which can effectively improve the overall degradation speed of the film paper and is beneficial to environmental protection, but also the film paper as a whole has good peel strength, oxygen transmission rate and water permeability.

[0018] 2. The degradable film paper provided by the present invention has an aluminized paper layer that can be bonded to a polylactic acid layer and a PBS layer, or to a PBS / PLA composite film layer through glue to form film papers with different structures. The raw materials of the polylactic acid layer, the PBS layer, and the PBS / PLA composite film layer are also degradable materials. Therefore, the formed film paper not only has a relatively high degradation rate, but also can further effectively optimize the overall peel strength, oxygen permeability, and water permeability of the film paper, and is compatible with the packaging requirements of different products.

[0019] 3. The preparation method of the degradable film paper provided by the present invention is compatible with existing soft packaging production lines and does not require additional equipment investment, thus effectively ensuring the low cost of film paper preparation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic diagram of the overall structure of the degradable film paper in the present invention Figure 1 。

[0021] Figure 2 is a schematic diagram of the overall structure of the degradable film paper in the present invention Figure 2 。

[0022] Figure 3 is a schematic diagram of the overall structure of the degradable film paper in the present invention Figure 3 。

[0023] The description of the reference numerals is as follows: 10. Aluminized paper layer; 100. Substrate layer; 200. Coating adhesive layer; 300. Barrier layer; 310. Aluminum oxide layer; 20. Polylactic acid layer; 30. PBS layer; 40. First glue composite layer; 50. Second glue composite layer; 60. PBS / PLA composite film layer; 70. Third glue composite layer. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] For ease of understanding of the present invention, the present invention will be described more comprehensively below in conjunction with specific embodiments. The present invention provides preferred embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0025] Before further describing various embodiments of the compounds / compositions and methods of the present disclosure in more detail by way of exemplary descriptions, examples, and results, it should be understood that the embodiments of the present disclosure are not limited in their application to the details of the methods and compositions described in the following description. The descriptions provided herein are for illustrative purposes only and are not to be construed in a limiting sense. The inventive concept of the present disclosure can have other embodiments or can be practiced or implemented in various ways. Therefore, the language used herein is intended to give the broadest scope and meaning; and the embodiments are intended to be exemplary and not exhaustive and are not intended to limit the present disclosure to these specific embodiments. Moreover, it should be understood that the wording and terminology employed herein are for descriptive purposes and should not be considered limiting unless otherwise specified. Additionally, in the following detailed description, numerous specific details are set forth in order to provide a more thorough understanding of the present disclosure.

[0026] However, it will be apparent to those of ordinary skill in the art that the embodiments of the present disclosure can be practiced without these specific details. In other instances, features well known to those of ordinary skill in the art have not been described in detail to avoid unnecessary complication of the description. It is intended that all alternatives, substitutions, modifications, and equivalents that are apparent to those of ordinary skill in the art be included within the scope of the present disclosure. In accordance with the present disclosure, all of the compounds / compositions disclosed herein and their preparation methods, applications, and uses can be prepared and implemented without undue experimentation.

[0027] Accordingly, although the compounds / compositions and methods of the present disclosure have been described in terms of specific embodiments, it will be apparent to those skilled in the art that changes can be made to the formulations, compounds or compositions, and / or methods, and to the steps or the order of steps of the methods described herein, without departing from the spirit and scope of the inventive concept of the present disclosure.

[0028] As used herein, any reference to "an embodiment" or "embodiments" means that a particular element, feature, structure, or property described in connection with that embodiment is included in at least one embodiment. The phrase "in one embodiment" that appears multiple times in the specification does not necessarily refer to the same embodiment.

[0029] Unless otherwise defined herein, scientific and technical terms used in connection with the present disclosure shall have the meanings commonly understood by those of ordinary skill in the art. Additionally, unless the context otherwise requires, singular terms shall include the plural and plural terms shall include the singular.

[0030] In a first aspect, the degradable film paper provided by the present invention is shown in the attached Figure 1, including an aluminized paper layer 10, the aluminized paper layer 10 includes a base material layer 100; a coating adhesive layer 200, which is respectively arranged on two surfaces of the base material layer 100 and is formed by curing a solvent-free adhesive coated on the surface of the base material layer 100; and a barrier layer 300, which is arranged on the side of the coating adhesive layer 200 away from the base material layer 100, and an alumina layer 310 is formed on the side away from the coating adhesive layer 200 through a vacuum evaporation process; and the peel strength of the aluminized paper layer 10 ≥ 2.5 N / 15 mm; the oxygen transmission rate at 23°C / 90% RH environment ≤ 15 cm 3 / m 2 .24h.1atm; the water permeability at 23°C / 90% RH environment ≤ 10 g / m 2 .24h. Preferably, the base material layer 100 is kraft paper of 30 g / m² - 100 g / m², which can provide good mechanical support and printing adaptability; further preferably, the aluminized paper layer 10 is 50 g / m² - 100 g / m².

[0031] Furthermore, the barrier layer 300 is a polylactic acid film layer, which is mixed by nano-alumina and polylactic acid in a mass percentage ratio of (1:99) - (10:90), with a thickness of 20μm - 40μm, and the thickness of the alumina layer 310 ≤ 0.5μm. Preferably, the average particle size of the nano-alumina is 5 nm - 100nm. Further, the polylactic acid is poly-L-lactic acid, which is formed by polycondensation or ring-opening polymerization of L-lactic acid and / or D-lactic acid with lactide as an intermediate, the mass percentage content of L-lactic acid > 90%, and the mass percentage content of D-lactic acid is 1% - 10%. Or, the polylactic acid is a copolymer-modified polylactic acid, which is polymerized by introducing a comonomer into the lactic acid unit, and the comonomer is glycolic acid or caprolactone, with a mass percentage content < 20%; or, it is mixed by adding 5% - 10% of polybutylene adipate terephthalate to the lactic acid unit.

[0032] Please refer to the appendix Figure 2, the degradable film paper provided by the present invention includes an aluminized paper layer 10, and also includes a polylactic acid layer 20 disposed on one side of the aluminized paper layer 10; a PBS layer 30 disposed on the other side of the aluminized paper layer 10; a first glue composite layer 40 disposed between the polylactic acid layer 20 and the aluminized paper layer 10; and a second glue composite layer 50 disposed between the PBS layer 30 and the aluminized paper layer 10. The film paper structure of the polylactic acid layer 20 - the first glue composite layer 40 - the aluminized paper layer 10 - the second glue composite layer 50 - the PBS layer 30 not only has a relatively high degradation rate, but also can further effectively optimize the overall peel strength, oxygen permeability and water permeability of the film paper, and is compatible with the packaging requirements of different products. Preferably, the thickness of the polylactic acid layer 20 is 10μm - 20μm; the thickness of the PBS layer 30 is 30μm - 50μm. Further, the polylactic acid used in the polylactic acid layer 20 is the same as that in the polylactic acid film layer, and can be poly-L-lactic acid, which is formed by polycondensation or ring-opening polymerization of L-lactic acid and / or D-lactic acid with lactide as an intermediate. The mass percentage content of L-lactic acid > 90%, and the mass percentage content of D-lactic acid is 1% - 10%. Alternatively, the polylactic acid is a copolymer-modified polylactic acid formed by introducing a comonomer into a lactic acid unit. The comonomer is glycolic acid or caprolactone, and the mass percentage content < 20%; or it is formed by adding 5% - 10% of polybutylene adipate terephthalate to the lactic acid unit.

[0033] Please refer to the appendix Figure 3 , the degradable film paper provided by the present invention includes an aluminized paper layer 10, and also includes a PBS / PLA composite film layer 60 disposed on both sides of the aluminized paper layer 10; and a third glue composite layer 70 disposed between the aluminized paper layer 10 and the PBS / PLA composite film layer 60. The film paper structure of the PBS / PLA composite film layer 60 - the third glue composite layer 70 - the aluminized paper layer 10 - the third glue composite layer 70 - the PBS / PLA composite film layer 60 not only has a relatively high degradation rate, but also can further effectively optimize the overall peel strength, oxygen permeability and water permeability of the film paper, and is compatible with the packaging requirements of different products. Preferably, the PBS / PLA composite film layer 60 is composed of 60% - 80% by mass of PBS and 20% - 40% by mass of PLA, and the thickness is 10μm - 20μm. Further, the polylactic acid used in the PLA is the same as that in the polylactic acid film layer, and can be poly-L-lactic acid, which is formed by polycondensation or ring-opening polymerization of L-lactic acid and / or D-lactic acid with lactide as an intermediate. The mass percentage content of L-lactic acid > 90%, and the mass percentage content of D-lactic acid is 1% - 10%. Alternatively, the polylactic acid is a copolymer-modified polylactic acid formed by introducing a comonomer into a lactic acid unit. The comonomer is glycolic acid or caprolactone, and the mass percentage content < 20%; or it is formed by adding 5% - 10% of polybutylene adipate terephthalate to the lactic acid unit.

[0034] Furthermore, the coating adhesive layer 200, the first glue composite layer 40, the second glue composite layer 50, and the third glue composite layer 70 are all formed by curing a polyurethane adhesive on the surface of the base material layer 100, and the solid content of the polyurethane adhesive is ≥ 99%; preferably, the coating amount of the polyurethane adhesive is 1.5 g / m² - 2.5 g / m². The polyurethane adhesive is a solvent-based environmentally friendly coating, which is friendly to the environment and can significantly improve the biodegradability and recyclability of the packaging during waste treatment.

[0035] Furthermore, after the polylactic acid layer 20 and the PBS layer 30 are respectively added to both sides of the aluminized paper layer 10, or after the PBS / PLA composite film layer 60 is added to both sides of the aluminized paper layer 10, for the film-paper structure, the PBS material can effectively improve the flexibility of the film-paper, and the PLA material can effectively enhance the mechanical strength and degradation rate of the film-paper, thereby further effectively optimizing the overall performance of the film-paper, resulting in the peel strength of the degradable film-paper being 10 N / 15mm - 15 N / 15mm; the oxygen permeability rate at 23°C / 90% RH ≤ 5 cm 3 / m 2 .24h.1atm; the water permeability rate at 23°C / 90% RH ≤ 1 g / m 2 .24h.

[0036] In a second aspect, the present invention also provides a method for preparing the above-mentioned degradable film-paper, which includes the following steps: S10. Prepare the aluminized paper layer; specifically, it includes the following steps: S11. Corona-treat the surface of kraft paper with a basis weight of 30 g / m² - 100 g / m² at a corona strength of ≥ 38 dyne / cm.

[0037] S12. Use a three-zone temperature-controlled screw extruder to extrude the barrier layer; specifically, S121. Mix the polylactic acid and nano-aluminum oxide raw materials with an average particle size of 5 nm - 100 nm in a mass percentage ratio of (1:99) - (10:90), and then add them to the screw extruder; S122. The screw extruder extrudes the barrier layer at a melting temperature of 170°C - 190°C in the feeding section, 180°C - 200°C in the plasticizing section, and 190°C - 220°C in the die head section, with an extrusion head pressure of 2 MPa - 10 MPa, a blown film air pressure of 0.1 MPa - 0.3 MPa, a casting roll temperature of 20°C - 50°C, and a blown film air ring cooling temperature of 10°C - 30°C, to obtain a barrier layer with a thickness of 20 μm - 40 μm; S123. Perform aluminizing treatment on the surface of the barrier layer away from the kraft paper side through a vacuum evaporation coating process, so that an aluminum oxide layer with a thickness ≤ 0.5 μm is formed on the surface of the barrier layer.

[0038] S13. Using a precision coating equipment, apply a solvent-free adhesive onto the surface of kraft paper at a coating amount of 1.5 g / m² - 2.5 g / m², and roll and laminate it with the uncoated side of the barrier layer under a pressure of 0.3 MPa - 0.5 MPa and a temperature of 60°C - 80°C. After curing at a temperature of 40°C - 50°C for 24h - 48h, an aluminized paper layer is obtained.

[0039] S20. Prepare the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer; specifically, S21. Dry the polylactic acid, PBS or PBS / PLA raw materials at 60°C for 4h to make the moisture content of the raw materials ≤ 0.05%, and then add them to a screw extruder. S22. The screw extruder has a melting temperature of 150°C in the feeding section, 170°C in the plasticizing section, and 180°C in the die head section, a die head temperature of 165°C, a screw speed of 50rpm - 80rpm, an extrusion pressure of 8 MPa - 12MPa, a cooling roll temperature of 20°C - 25°C, and a traction speed of 10m / min - 15 m / min to obtain the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer.

[0040] S30. Using a precision coating equipment, apply a solvent-free adhesive onto the surface of the aluminized paper layer at a coating amount of 1.5 g / m² - 2.5 g / m², and then stack the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer prepared in step S22 on the adhesive layer, and roll and laminate it under a pressure of 0.3 MPa - 0.5 MPa and a temperature of 60°C - 80°C. After curing at a temperature of 40°C - 50°C for 24h - 48h, cut it to obtain a degradable film paper.

[0041] In the following specific examples, the sources of the main raw materials and main equipment used are as follows: Kraft paper: Supercalendered coated paper Polyurethane adhesive: Henkel 2770 from Germany PLA resin: Ingeo 6252D; Nano-aluminum oxide: Evonik Aeroxide® Alu C 80 from Germany PBS resin: BASF Ecovio® F2330 Screw extruder: Reifenhäuser EVOLUTION Ultra 1300 Precision coating equipment: Zhencheng Technology DM-1250 Corona equipment: Nordmech NDM-1200 Example 1: This embodiment provides a method for preparing a degradable film paper, comprising the following steps: S10. Prepare an aluminized paper layer; specifically, the following steps are included: S11. Corona-treat the surface of 80 g / m² kraft paper at a corona intensity of 48 dyne / cm.

[0042] S12. Extrude a barrier layer by means of three-stage temperature control using a screw extruder; specifically, S121. Mix nano-aluminum oxide with an average particle size of 50 nm and a polylactic acid raw material in a mass percentage ratio of 5:95, and then add them to the screw extruder; wherein, the polylactic acid is poly-L-lactic acid, which is formed by polycondensation or ring-opening polymerization of L-lactic acid and D-lactic acid with lactide as an intermediate. The mass percentage content of L-lactic acid is 95%, and the mass percentage content of D-lactic acid is 5%.

[0043] S122. Using a melting temperature of 180 °C for the feeding section, 190 °C for the plasticizing section, and 215 °C for the die head section in the screw extruder, an extrusion head pressure of 6 MPa, a blowing film air pressure of 0.2 MPa, a cooling temperature of 35 °C for the casting roller and 20 °C for the blowing film air ring, prepare a 30-μm barrier layer; S123. Perform aluminizing treatment on the surface of the barrier layer away from the kraft paper side through a vacuum evaporation process, so that an aluminum oxide layer with a thickness ≤ 0.5 μm is formed on the surface of the barrier layer.

[0044] S13. Using a precision coating device, coat the surface of the kraft paper with a solvent-free adhesive at a coating amount of 2 g / m², and roll-compound it with the non-aluminized side of the barrier layer under a pressure of 0.4 MPa and a temperature of 70 °C, and cure it at a temperature of 45 °C for 36 h to obtain an aluminized paper layer. After slitting, it can be used alone as degradable film paper 1.

[0045] Example 2: The preparation method in this embodiment is the same as that in Example 1, and the main differences are as follows: In step S11, the kraft paper is 30 g / m² and the corona intensity is 38 dyne / cm; In step S121, the polylactic acid is a copolymer-modified polylactic acid, which is polymerized by introducing a glycolic acid comonomer into a lactic acid unit. The mass percentage content of the glycolic acid monomer is 15%, and the mass percentage ratio of nano-aluminum oxide to polylactic acid is 10:90; In step S122, the thickness of the prepared barrier layer is 20 μm; In step S13, an aluminized paper layer is obtained. After slitting, it can be used alone as degradable film paper 2.

[0046] Example 3: The preparation method in this embodiment is the same as that in Example 1, and the main differences are as follows: In step S11, the kraft paper is 100 g / m² and the corona strength is 48 dyne / cm; In step S121, the polylactic acid is mixed by adding 7.5% of polybutylene adipate - terephthalate to lactic acid units. The average particle size of nano - alumina is 100 nm, and the mass percentage ratio of nano - alumina to polylactic acid is 1:99; In step S122, the prepared barrier layer has a thickness of 40 μm; In step S13, an aluminized paper layer is obtained. After slitting, it can be used alone as the degradable film paper 3.

[0047] Example 4: The preparation method in this example is the same as that in Example 1. The main difference is that it further includes the following steps. S20. Prepare a polylactic acid layer and a PBS layer; specifically, S21. Dry the polylactic acid and PBS raw materials at 60 °C for 4 h until the moisture content of the raw materials is ≤0.05%, and then add them to a screw extruder. Among them, the polylactic acid raw material is poly - L - lactic acid, which is formed by polycondensation or ring - opening polymerization of L - lactic acid and D - lactic acid with lactide as an intermediate. The mass percentage content of L - lactic acid is 99%, and the mass percentage content of D - lactic acid is 1%; S22. The screw extruder extrudes at a melting temperature of 150 °C in the feeding section, 170 °C in the plasticizing section, and 180 °C in the die head section, with a die head temperature of 165 °C, a screw speed of 65 rpm, an extrusion pressure of 10 MPa, a cooling roll temperature of 22.5 °C, and a traction speed of 12.5 m / min to obtain the corresponding polylactic acid layer and PBS layer. The thickness of the polylactic acid layer is 15 μm, and the thickness of the PBS layer is 40 μm.

[0048] S30. Using a precision coating device, coat the surface of the aluminized paper layer with a solvent - free adhesive at a coating amount of 2.0 g / m². Then stack the corresponding polylactic acid layer and PBS prepared in step S22 on the adhesive layer respectively, and roll - press and compound them at a pressure of 0.4 MPa and a temperature of 70 °C, and cure them at a temperature of 45 °C for 36 h, and then slit to obtain the degradable film paper 4.

[0049] Example 5: The preparation method in this example is the same as that in Example 1. The main difference is that it further includes the following steps. S20. Prepare a PBS / PLA composite film layer; specifically, S21. Mix the polylactic acid and PBS raw materials according to 70% by mass of PBS and 30% by mass of PLA, dry them at 60 °C for 4 h until the moisture content of the raw materials is ≤0.05%, and then add them to a screw extruder; S22. The spiral extruder uses a melting temperature of 150°C for the feeding section, 170°C for the plasticizing section, and 180°C for the die head section, a die head temperature of 165°C, a screw speed of 65 rpm, an extrusion pressure of 10 MPa, a cooling roll temperature of 23°C, and a traction speed of 12.5 m / min to produce a PBS / PLA composite film layer with a thickness of 15 μm for the PBS / PLA composite film layer.

[0050] S30. Using a precision coating device, apply a solvent-free adhesive at a coating amount of 2.0 g / m² onto the surface of the aluminized paper layer. Subsequently, stack the PBS / PLA composite film layer obtained in step S22 on the adhesive layer, and roll and laminate it at a pressure of 0.4 MPa and a temperature of 70°C. After curing at a temperature of 45°C for 36 h, cut it to obtain the degradable film paper 5.

[0051] Example 6: The preparation method in this example is the same as that in Example 5, and the main difference is that In step S21, after mixing PBS raw material and PLA raw material according to 80% by mass percentage of PBS and 20% by mass percentage of PLA, the degradable film paper 6 is obtained.

[0052] Example 7: The preparation method in this example is the same as that in Example 2, and the main difference is that it further includes the following steps S20. Prepare a polylactic acid layer and a PBS layer; specifically, S21. Dry the polylactic acid and PBS raw materials at 60°C for 4 h to make the moisture content of the raw materials ≤ 0.05%, and then add them to the spiral extruder; among them, the polylactic acid raw material is a copolymer-modified polylactic acid, which is polymerized by introducing a caprolactone comonomer into the lactic acid unit, and the mass percentage of the caprolactone comonomer is 10%; S22. The spiral extruder uses a melting temperature of 150°C for the feeding section, 170°C for the plasticizing section, and 180°C for the die head section, a die head temperature of 165°C, a screw speed of 50 rpm, an extrusion pressure of 8 MPa, a cooling roll temperature of 20°C, and a traction speed of 10 m / min to produce the corresponding polylactic acid layer and PBS layer. The thickness of the polylactic acid layer is 10 μm, and the thickness of the PBS layer is 30 μm.

[0053] S30. Using a precision coating device, apply a solvent-free adhesive at a coating amount of 1.5 g / m² onto the surface of the aluminized paper layer. Subsequently, stack the corresponding polylactic acid layer and PBS obtained in step S22 on the adhesive layer respectively, and roll and laminate them at a pressure of 0.3 MPa and a temperature of 60°C. After curing at a temperature of 40°C for 48 h, cut it to obtain the degradable film paper 7.

[0054] Example 8: The preparation method in this example is the same as that in Example 2. The main difference is that the following steps are further included. S20. Prepare a PBS / PLA composite film layer. Specifically, S21. After mixing polylactic acid and PBS raw materials with 70% by mass of PBS and 30% by mass of PLA, dry them at 60 °C for 4 h to make the moisture content of the raw materials ≤ 0.05%, and then add them to a screw extruder. Among them, the polylactic acid raw material is a copolymer-modified polylactic acid, which is polymerized by introducing a caprolactone comonomer into lactic acid units, and the mass percentage content of the caprolactone comonomer is 15%. S22. The screw extruder uses a melting temperature of 150 °C in the feeding section, 170 °C in the plasticizing section, and 180 °C in the die head section, a die head temperature of 165 °C, a screw speed of 50 rpm, an extrusion pressure of 8 MPa, a cooling roll temperature of 20 °C, and a traction speed of 10 m / min to produce a PBS / PLA composite film layer with a thickness of 10 μm.

[0055] S30. Use a precision coating device to coat the surface of the aluminized paper layer with a solvent-free adhesive at a coating amount of 1.5 g / m². Then stack the PBS / PLA composite film layer prepared in step S22 on the adhesive layer, and roll and compound it at a pressure of 0.5 MPa and a temperature of 80 °C, and cure it at a temperature of 50 °C for 36 h, and then slit it to obtain the degradable film paper 8.

[0056] Example 9: The preparation method in this example is the same as that in Example 8. The main difference is that In step S21, after mixing polylactic acid and PBS raw materials with 60% by mass of PBS and 40% by mass of PLA, the degradable film paper 9 is obtained.

[0057] Example 10: The preparation method in this example is the same as that in Example 3. The main difference is that the following steps are further included. S20. Prepare a polylactic acid layer and a PBS layer. Specifically, S21. After drying the polylactic acid and PBS raw materials at 60 °C for 4 h to make the moisture content of the raw materials ≤ 0.05%, add them to a screw extruder. Among them, the polylactic acid raw material is a mixture of lactic acid units and 10% of polybutylene adipate terephthalate. S22. The screw extruder uses a melting temperature of 150°C in the feeding section, 170°C in the plasticizing section, and 180°C in the die head section, a die head temperature of 165°C, a screw rotation speed of 80 rpm, an extrusion pressure of 12 MPa, a cooling roll temperature of 25°C, and a traction speed of 15 m / min to produce the corresponding polylactic acid layer and PBS layer. The thickness of the polylactic acid layer is 20 μm, and the thickness of the PBS layer is 50 μm.

[0058] S30. Using a precision coating equipment, apply a solvent-free adhesive onto the surface of the aluminized paper layer at a coating amount of 2.5 g / m². Subsequently, stack the corresponding polylactic acid layer and PBS prepared in step S22 on the adhesive layer respectively, and roll and laminate them at a pressure of 0.5 MPa and a temperature of 80°C. After curing at a temperature of 50°C for 24 h, slit it to obtain the degradable film paper 10.

[0059] Example 11: The preparation method in this example is the same as that in Example 3, and the main difference is that it further includes the following steps. S20. Prepare a PBS / PLA composite film layer; specifically, S21. Mix polylactic acid and PBS raw materials according to 80% by mass of PBS and 20% by mass of PLA, dry them at 60°C for 4 h to make the moisture content of the raw materials ≤ 0.05%, and then add them to the screw extruder; among them, the polylactic acid raw material is composed of lactic acid units mixed with 5% of polybutylene adipate-co-terephthalate. S22. The screw extruder uses a melting temperature of 150°C in the feeding section, 170°C in the plasticizing section, and 180°C in the die head section, a die head temperature of 165°C, a screw rotation speed of 80 rpm, an extrusion pressure of 12 MPa, a cooling roll temperature of 25°C, and a traction speed of 15 m / min to produce a PBS / PLA composite film layer with a thickness of 20 μm.

[0060] S30. Using a precision coating equipment, apply a solvent-free adhesive onto the surface of the aluminized paper layer at a coating amount of 2.5 g / m². Subsequently, stack the PBS / PLA composite film layer prepared in step S22 on the adhesive layer, and roll and laminate them at a pressure of 0.5 MPa and a temperature of 80°C. After curing at a temperature of 50°C for 36 h, slit it to obtain the degradable film paper 11.

[0061] Example 12: The preparation method in this example is the same as that in Example 11, and the main difference is that In step S21, after mixing polylactic acid and PBS raw materials according to 60% by mass of PBS and 40% by mass of PLA, the degradable film paper 12 is obtained.

[0062] Comparative Example 1: The preparation method in this comparative example is the same as that in Example 1, and the main difference is that: In the raw materials of the barrier layer, nano-aluminum oxide was not added, and the vacuum evaporation coating process was not carried out. The remaining steps and parameters remained unchanged, and Membrane Paper 1 was prepared.

[0063] Comparative Example 2: The preparation method in this comparative example is the same as that in Example 1, and the main difference is that: After the solvent-free adhesive was coated on the surface of the kraft paper, the barrier layer was placed on the adhesive layer, and the remaining steps and parameters remained unchanged. Membrane Paper 2 was prepared by curing at room temperature.

[0064] Comparative Example 3: The preparation method in this comparative example is the same as that in Example 4, and the main difference is that: The raw materials of polylactic acid and PBS were respectively at a melting temperature of 180 °C, and the remaining parameters remained unchanged. After the corresponding polylactic acid layer and PBS layer were made, the remaining steps remained unchanged, and Membrane Paper 3 was prepared.

[0065] Comparative Example 4: The preparation method in this comparative example is the same as that in Example 4, and the main difference is that: After the solvent-free adhesive was coated on the surface of the aluminized paper layer, the polylactic acid layer and the PBS layer were respectively placed on the adhesive layer, and the remaining steps and parameters remained unchanged. Membrane Paper 4 was prepared by curing at room temperature.

[0066] Comparative Example 5: The preparation method in this comparative example is the same as that in Example 4, and the main difference is that: Polyethylene (PE) was used to replace the raw materials of polylactic acid and PBS to make a polyethylene (PE) layer, and the remaining steps and parameters remained unchanged, and Membrane Paper 5 was prepared.

[0067] Comparative Example 6: The preparation method in this comparative example is the same as that in Example 5, and the main difference is that: Polypropylene (PP) was used to replace the raw materials of polylactic acid and PBS to make a polypropylene (PP) layer, and the remaining steps and parameters remained unchanged, and Membrane Paper 6 was prepared.

[0068] Comparative Example 7: Commercially available environmentally friendly membrane paper product 1.

[0069] Comparative Example 8: Commercially available environmentally friendly membrane paper product 2.

[0070] Test Example: The membrane papers in Examples 1-12 and Comparative Examples 1-8 were respectively cut into membrane paper samples of 5 cm × 1 cm, and tested according to the following test methods. The test results are shown in Table 1.

[0071] 1. Peel strength: Referring to the standard of GB 2792-2014, the peel strength tests were respectively carried out on the film-paper samples prepared in Examples 1-12 and Comparative Examples 1-8. 2. Oxygen permeability: Referring to the standard of ASTM F1927, the oxygen permeability tests were respectively carried out on the film-paper samples prepared in Examples 1-12 and Comparative Examples 1-8. 3. Water permeability: Referring to the standard of ASTM E96, the oxygen permeability tests were respectively carried out on the film-paper samples prepared in Examples 1-12 and Comparative Examples 1-8. 4. Biodegradation rate: The film-paper samples in Examples 1-12 and Comparative Examples 1-8 were respectively stacked into 5 film-paper samples of 1 m³, and referring to the standard of EN 13432, the biodegradation rate tests were respectively carried out on the film-paper samples in Examples 1-12 and Comparative Examples 1-8.

[0072] Table 1 Performance and biodegradation rate parameter table of Examples 1-12 and Comparative Examples 1-8

[0073] As can be seen from Table 1, the degradable film-papers prepared in Examples 1-3 have better peel strength, oxygen permeability and air permeability compared with the film-papers prepared in Comparative Examples 1-2, and the degradable film-papers prepared in Examples 4-12 have better peel strength, oxygen permeability and air permeability compared with the film-papers prepared in Comparative Examples 3-4. Among them, the peel strength of Examples 1-3 ≥ 2.5 N / 15 mm, the oxygen permeability ≤ 15 cm 3 / m 2 .24 h.1 atm, the air permeability ≤ 10 g / m 2 .24 h, the peel strength of Examples 4-12 is 10 N / 15 mm - 15 N / 15 mm, the oxygen permeability ≤ 5 cm 3 / m 2 .24 h.1 atm, the air permeability ≤ 1 g / m 2 .24 h, which can effectively meet the requirements of product packaging; the degradable film-papers prepared in Examples 1-12 have a higher biodegradation rate compared with the film-papers prepared in Comparative Examples 5-6. Especially for the degradable film-paper in Example 5, the biodegradation rate can reach 90% in 60 days. Moreover, the degradable film-papers prepared in Examples 1-12 have better effects in peel strength, oxygen permeability, air permeability and biodegradation rate compared with the environmental protection film-paper products 1-2.

[0074] The above content is only an example and illustration of the structure of the present invention. Its description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these obvious alternative forms all fall within the protection scope of the present invention.

Claims

1. A degradable film paper, characterized in that, It includes an aluminized paper layer, and the aluminized paper layer includes: A base material layer; Coating adhesive layers, which are respectively arranged on two surfaces of the base material layer and are formed by curing a solvent-free adhesive coated on the surface of the base material layer; And a barrier layer, which is arranged on one surface of the coating adhesive layer away from the base material layer, and an alumina layer is formed on the surface away from the coating adhesive layer through a vacuum evaporation process; And the peel strength of the aluminized paper layer ≥ 2.5 N / 15 mm; the oxygen transmission rate at 23°C / 90% RH environment ≤ 15 cm 3 / m 2 .24 h.1 atm; the water permeability at 23°C / 90% RH environment ≤ 10 g / m 2 .24 h.

2. The degradable membrane paper according to claim 1, wherein The barrier layer is a polylactic acid film layer, which is formed by mixing nano-alumina and polylactic acid in a mass percentage ratio of (1:99)-(10:90), and the thickness is 20μm - 40μm; the thickness of the alumina layer ≤ 0.5μm.

3. The degradable membrane paper according to claim 2, wherein The polylactic acid is poly-L-lactic acid, which is formed by polycondensation or ring-opening polymerization of L-lactic acid and / or D-lactic acid with lactide as an intermediate, the mass percentage content of L-lactic acid > 90%, and the mass percentage content of D-lactic acid is 1% - 10%.

4. The degradable film paper according to claim 2, wherein The polylactic acid is a copolymer-modified polylactic acid, which is formed by introducing a comonomer into a lactic acid unit for polymerization, and the comonomer is glycolic acid or caprolactone, and the mass percentage content < 20%; Or it is formed by mixing 5% - 10% of polybutylene adipate terephthalate in the lactic acid unit.

5. The degradable membrane paper according to claim 1, characterized in that, It also includes: A polylactic acid layer, which is arranged on one surface of the aluminized paper layer; A PBS layer, which is arranged on the other surface of the aluminized paper layer; A first glue composite layer, which is arranged between the polylactic acid layer and the aluminized paper layer; And a second glue composite layer, which is arranged between the PBS layer and the aluminized paper layer.

6. The degradable film paper according to claim 1, wherein It also includes: A PBS / PLA composite film layer, which is respectively arranged on two surfaces of the aluminized paper layer; And a third glue composite layer, which is arranged between the aluminized paper layer and the PBS / PLA composite film layer.

7. The degradable film paper according to claim 6, wherein The PBS / PLA composite film layer is formed by mixing PBS with a mass percentage content of 60% - 80% and PLA with a mass percentage content of 20% - 40%, and the thickness is 10μm - 20μm.

8. The degradable film paper according to claim 1 or 5 or 6, characterized in that, The coating adhesive layer, the first glue composite layer, the second glue composite layer and the third glue composite layer are all formed by curing a polyurethane adhesive coated on the surface of the base material layer, and the solid content of the polyurethane adhesive ≥ 99%.

9. The degradable film paper according to claim 5 or 6, characterized in that, The peel strength is 10 N / 15mm - 15N / 15mm; the oxygen transmission rate at 23°C / 90% RH environment is ≤ 5 cm 3 / m 2 .24h.1atm; the water permeability at 23°C / 90% RH environment is ≤ 1 g / m 2 .24h.

10. A preparation method of the degradable membrane paper as described in any one of claims 1-9, characterized in that, It includes the following steps: S10. Prepare the aluminized paper layer; S20. Prepare the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer; S30. Use a precision coating device to coat a solvent-free adhesive on the surface of the aluminized paper layer, and then stack the corresponding polylactic acid layer, PBS layer or PBS / PLA composite film layer on the glue layer, roll and compound, cure and slit to obtain a degradable film paper; where In the step of preparing the aluminized paper layer, it includes the following steps: S11. Conduct corona treatment on the surface of the base material layer; S12. Use a three-stage temperature control method in a screw extruder to extrude the barrier layer, and an alumina layer is formed on the surface of the barrier layer through a vacuum evaporation process; S13. Use a precision coating device to coat a solvent-free adhesive on the surface of the base material layer, and roll and compound it with the non-aluminized side of the barrier layer, and after curing, obtain the aluminized paper layer.

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