Polylactic acid composite material for packaging bottle and preparation method of polylactic acid composite material

Abstract

The invention discloses a polylactic acid composite material for a packaging bottle and a preparation method of the polylactic acid composite material. The polylactic acid composite material for the packaging bottle is prepared from the following components in parts by mass: 50 to 70 parts of polylactic acid, 10 to 30 parts of poly (epsilon-caprolactone), 10 to 30 parts of poly (propylene carbonate), 30 to 50 parts of functional master batch and 0.1 to 0.5 part of antioxidant, the functional master batch is prepared from a polylactic acid-modified nano silicon dioxide-poly (propylene carbonate) graft and a polylactic acid-modified nano silicon dioxide-poly (epsilon-caprolactone) graft; the modified nano silicon dioxide is 4-phenylethynyl phthalic anhydride modified nano silicon dioxide. The modified nano silicon dioxide is obtained by adopting an ultrasonic blending method, and different macromolecular substances are bonded through the modified nano silicon dioxide by utilizing an electron irradiation method to obtain a modified graft, so that the surface energy of particles can be reduced, the agglomeration among the particles can be reduced, and the dispersing performance of the nano silicon dioxide can be improved.

Description

Technical Field

[0001] This application relates to the field of polymer materials, and more particularly to a polylactic acid composite material for packaging bottles and its preparation method. Background Technology

[0002] The poor barrier properties of polymer materials are a key factor limiting their application in the packaging field. Barrier properties can be improved by altering the material's microstructure, employing multilayer composites, and blending modifications. Currently, with increasing environmental awareness, there is an urgent need to find biodegradable materials to replace synthetic polymers in the packaging industry; however, the performance of biodegradable materials themselves is not ideal.

[0003] Different packaging materials and barrier technologies can be combined to create packaging barrier solutions with varying degrees of protection. Appropriate barrier technologies can be selected based on existing production conditions and barrier requirements to apply to product packaging, achieving high-quality packaging protection while controlling costs. Furthermore, the sustainable development of barrier packaging needs to be considered, promoting its green and circular development (Packaging Engineering Vol.4 No.3 P92 2020). CN111019308A utilizes silica aerogel and polylactic acid composites, leveraging the lightweight, porous structure and excellent thermal insulation properties of silica aerogel to prepare heat-insulating PLA plastic bottles. CN109111710A discloses a method for preparing heat-resistant PLA-based biodegradable plastic bottles, utilizing polycarbonate and PLA composites to improve heat resistance, and the hollow structure of ZnO spheres to enhance material transparency, antibacterial properties, and other characteristics. CN112708250A utilizes the modified crystallization properties of L-, D-, and meso polylactic acid to improve transparency, and the addition of polyamide PA6I / 6T to improve the heat resistance and barrier properties of polylactic acid. CN105691858A uses a multilayer co-extrusion method to improve barrier properties. CN106751625A uses grape pomace extract, hydrophobic nano-silica, and polyester to enhance the high barrier properties of polylactic acid. CN104877315A involves inserting caprolactone monomers into the layers of montmorillonite to obtain modified polycaprolactone-modified montmorillonite, which is then co-extruded with polylactic acid to obtain a barrier masterbatch, thereby improving the barrier properties of polylactic acid. CN118772821A uses an adhesive prepared from PDLA-PCL-PEF grafts as the middle layer of the packaging bottle to improve the compatibility, mechanical properties, and barrier properties of PLA and polyethylene furanate dicarboxylate (PEF) blends. Meanwhile, polylactic acid is used as the inner and outer layers, and the adhesive is used as the middle layer to form the packaging bottle material. The packaging bottle is prepared through a five-layer co-extrusion blow molding process. The invention "PPC and PHBV and PLA, PBS, PBAT and PCL blends and preparation methods" published by CN201010194914 is similar to the invention "PPC, PCL, PLA, PBS and PBAT blends and preparation methods" published by Nabuqi in (Science and Technology Information: No. 15. P430 2013). Both inventions utilize end-capping agents and modified light calcium carbonate to ensure the zipper-like thermal decomposition and binding of PPC into blocks. Lubricants are added to ensure smooth processing. The mixing of PPC, PCL, PLA, PBS and PBAT can complement each other's excellent properties, improve the performance of the blends and reduce costs. The preparation is completed in only two steps: cold mixing and extrusion granulation. Other inventions such as CN118876551A, CN118480202A, CN113619242A, CN112280260A and CN118027476A all involve polylactic acid barrier.The materials used in packaging bottles have been given higher performance requirements, needing to meet the requirements of biodegradability while improving their barrier properties and mechanical properties.

[0004] Therefore, developing a biodegradable material with barrier properties is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, this application provides a polylactic acid composite material for packaging bottles, which can meet the requirements of good comprehensive performance in terms of barrier properties, mechanical properties, heat resistance and processing performance, and the processing is green and environmentally friendly and easy to industrialize.

[0006] This application utilizes the multifunctional monomer phenylacetylene phthalic anhydride to modify nano-silica. The basic principle is that 4-phenylethynylphthalic anhydride can be hydrolyzed to phenylethynyl phthalic acid, and then the carboxylic acid group anchors the hydroxyl groups on the surface of nano-SiO2 to form a core-shell particle structure; electron beam initiation is used. The phenylacetylene groups on the polymer matrix are grafted onto the polymer matrix to obtain a graft copolymer of core-shell particles and macromolecules. This graft copolymer not only enhances interfacial bonding, improves material strength and heat resistance, but also strengthens the barrier properties of polylactic acid composites used in packaging bottles.

[0007] This application provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 50 to 70 parts of polylactic acid (PLA), 10 to 30 parts of poly(ε-caprolactone) (PCL), 10 to 30 parts of polypropylene carbonate (PPC), 30 to 50 parts of functional masterbatch, and 0.1 to 0.5 parts of antioxidant;

[0008] The functional masterbatch includes polylactic acid-modified nano silica-polypropylene carbonate graft and polylactic acid-modified nano silica-polyε-caprolactone graft.

[0009] The modified nano-silica is 4-phenylethynylphthalic anhydride modified nano-silica.

[0010] The polylactic acid composite material for packaging bottles described in this application includes functional masterbatches. In some specific implementations, the functional masterbatch includes polylactic acid-modified nano-silica-polypropylene carbonate grafts and polylactic acid-modified nano-silica-poly(ε-caprolactone) grafts, wherein the polylactic acid-modified nano-silica-poly(ε-caprolactone) graft ( The mass ratio of polylactic acid, modified nano-silica, and poly(ε-caprolactone) in the polylactic acid-modified nano-silica graft copolymer is 7:(2-3):3, which can be 7:2:3, 7:2.5:3, or 7:3:3. The functional masterbatch serves to enhance the adhesion between components and improve the compatibility and barrier properties of polylactic acid composites for packaging bottles. In some specific implementations, the polylactic acid-modified nano-silica-polypropylene carbonate graft copolymer (… The mass ratio of polylactic acid, modified nano-silica, and polypropylene carbonate in the functional masterbatch is 7:(2-3):3, which can be 7:2:3, 7:2.5:3, or 7:3:3. In some specific implementations, the mass ratio of polylactic acid-modified nano-silica-polypropylene carbonate graft to polylactic acid-modified nano-silica-polyε-caprolactone graft in the functional masterbatch is 1:(0.8-1.2), preferably 1:1. In some specific implementations, the mass ratio of nano-silica to 4-phenylethynyl phthalic anhydride in the modified nano-silica is 2:(0.5-1.5), which can be 2:0.5, 2:0.6, 2:0.8, 2:1, 2:1.2, 2:1.4, or 2:1.5. The functional masterbatch is present in parts by weight of 30 to 50, specifically 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, and 50. Adding the functional masterbatch to polylactic acid (PLA) composites for packaging bottles not only improves the dispersion of silica within the PLA system but also enhances the compatibility of PLA, PPC, and PCL, thereby improving the mechanical properties of the PLA composites and increasing the barrier properties of the packaging bottles.

[0011] The polylactic acid composite material for packaging bottles described in this application includes polylactic acid. In some specific implementations, the number-average molecular weight of the polylactic acid is 250,000. The mass fraction of the polylactic acid is 50 to 70 parts, specifically 50, 52, 54, 56, 58, 60, 62, 64, 65, 66, 68, or 70 parts.

[0012] The polylactic acid composite material for packaging bottles described in this application includes poly(ε-caprolactone). In some specific implementations, the number-average molecular weight of the poly(ε-caprolactone) is 80,000. The mass fraction of the ε-caprolactone is from 10 to 30 parts, and can be 10, 12, 14, 16, 18, 20, 22, 24, 25, 26, 28, or 30 parts.

[0013] The polylactic acid composite material for packaging bottles described in this application includes polypropylene carbonate. In some specific implementations, the number-average molecular weight of the polypropylene carbonate is 40,000. The mass fraction of the polypropylene carbonate is from 10 to 30 parts, specifically 10, 12, 14, 16, 18, 20, 22, 24, 25, 26, 28, or 30 parts.

[0014] The polylactic acid composite material for packaging bottles described in this application includes an antioxidant. In some specific implementations, the antioxidant includes, but is not limited to, antioxidant 1010. This application does not have special requirements for the selection of antioxidants. The antioxidant is present in parts by weight of 0.1 to 0.5 parts, and can be 0.1, 0.2, 0.3, 0.4, or 0.5 parts.

[0015] This application also provides a method for preparing polylactic acid composite material for packaging bottles, comprising:

[0016] Polylactic acid, poly(ε-caprolactone), polypropylene carbonate, functional masterbatch and antioxidant are mixed and melt-extruded to obtain polylactic acid composite material for packaging bottles;

[0017] The functional masterbatch includes polylactic acid-modified nano silica-polypropylene carbonate graft and polylactic acid-modified nano silica-polyε-caprolactone graft.

[0018] The modified nano-silica is 4-phenylethynylphthalic anhydride modified nano-silica.

[0019] This application utilizes the multifunctional monomer 4-phenylethynylphthalic anhydride to modify nano-silica. A core-shell particle structure is formed, and polymer macromolecules are grafted onto the surface of nano-silica using an irradiation grafting method to obtain a graft copolymer of core-shell particles and macromolecules.

[0020] This application first mixes nano-silica with 4-phenylethynylphthalic anhydride to obtain modified nano-silica. In some specific implementations, the mass ratio of the nano-silica to 4-phenylethynylphthalic anhydride or phenylethynylphthalic acid is 2:(0.5-1.5), which can be 2:0.5, 2:0.6, 2:0.8, 2:1, 2:1.2, 2:1.4, or 2:1.5. In some specific implementations, the mixing process further includes cooling, washing, filtering, and drying. The mixing temperature is 60°C to 100°C, and the mixing time is 4 to 6 hours. In some specific implementations, the mixing is carried out in a solvent, which includes, but is not limited to, N-methylpyrrolidone. This application does not have specific requirements for the choice of solvent.

[0021] This application then involves melt extruding, granulating, drying, and electron beam irradiating polylactic acid, modified nano-silica, and polypropylene carbonate to obtain a polylactic acid-modified nano-silica-polypropylene carbonate graft; and melt extruding, granulating, and electron beam irradiating polylactic acid, modified nano-silica, and polyε-caprolactone to obtain a polylactic acid-modified nano-silica-polyε-caprolactone graft. In some specific implementations, the mass ratio of polylactic acid, modified nano-silica, and polypropylene carbonate is 7:(2-3):3, which can be 7:2:3, 7:2.5:3, or 7:3:3. The absorbed dose of the electron beam radiation is from 3 kGy to 100 kGy, which can be 3 kGy, 5 kGy, 10 kGy, 15 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 80 kGy, 90 kGy, 95 kGy, or 100 kGy. The temperature of the melt extrusion is a commonly used temperature in the prior art. In some specific implementations, the mass ratio of polylactic acid, modified nano-silica, and poly(ε-caprolactone) is 7:(2-3):3, which can be 7:2:3, 7:2.5:3, or 7:3:3. The absorbed dose of the electron beam radiation is from 3 kGy to 100 kGy, which can be 3 kGy, 5 kGy, 10 kGy, 15 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 80 kGy, 90 kGy, 95 kGy, or 100 kGy. The temperature of the melt extrusion is a commonly used temperature in existing technologies. Compared with general chemical grafting and irradiation grafting methods, this method is easier to operate and control. It can be completed at room temperature or even low temperature. The irradiation grafting reaction can be confined to the polymer surface or within a specified thickness, or it can occur inside the polymer. The grafting rate can be controlled as needed. The irradiation grafting reaction is initiated by radiation, and there is no need to add initiators or other chemical additives to the grafting system. The preparation process is green and environmentally friendly. Under the initiation of a high-energy electron beam, the double or triple bonds in the polyfunctional monomers open and undergo an addition reaction with the carbonyl group in the polylactic acid molecule. Some polylactic acid molecular chains break randomly and undergo structural recombination after being "connected" by the polyfunctional monomers to form branched or cross-linked structures.

[0022] This application then uses polylactic acid-modified nano-silica-polypropylene carbonate grafts and polylactic acid-modified nano-silica-polyε-caprolactone grafts to obtain functional masterbatches through high-speed stirring, melt extrusion, granulation, and drying processes. In some specific implementations, the melt extrusion temperature is a commonly used temperature in the prior art.

[0023] This application then mixes, melt-extrudes, and granulates polylactic acid, poly(ε-caprolactone), polypropylene carbonate, functional masterbatch, and antioxidant to obtain a polylactic acid composite material for packaging bottles. In some specific implementations, the melt extrusion temperature is a commonly used temperature in the prior art. The polylactic acid composite material for packaging bottles can be used to prepare packaging bottles through a one-step extrusion blow molding process or a two-step injection and blow molding process.

[0024] Blending modification can effectively improve the heat resistance, mechanical properties, and barrier properties of biodegradable materials, meeting packaging requirements. Different packaging materials and barrier technologies can be combined to create packaging barrier solutions with varying degrees of protection. Appropriate barrier technologies can be selected and applied to product packaging based on existing production conditions and barrier requirements, achieving high-quality packaging protection while controlling costs. Furthermore, it is necessary to focus on the sustainable development of barrier packaging, promoting its green and circular development.

[0025] This application employs ultrasonic blending to obtain modified nano-silica, and uses electron irradiation to bond different macromolecular substances through modified nano-silica to obtain modified grafts. This not only reduces the surface energy of the particles and decreases particle aggregation, improving the dispersion performance of nano-silica, but also enhances its compatibility with organic components. The preparation of functional masterbatch further improves the compatibility between the components of polylactic acid composite materials for packaging bottles, meeting the comprehensive requirements of the product in terms of barrier properties, mechanical properties, heat resistance, and processing performance. Detailed Implementation

[0026] It should be understood that the expression “one or more of…” individually includes each of the objects described after the expression, as well as various different combinations of two or more of the described objects, unless otherwise understood from the context and usage. The expression “and / or” combined with three or more described objects should be understood to have the same meaning, unless otherwise understood from the context.

[0027] The terms “including,” “having,” or “containing,” including the use of their grammatical synonyms, should generally be understood as open-ended and non-restrictive, for example, not excluding other unstated elements or steps, unless otherwise specifically stated or understood from the context.

[0028] It should be understood that the order of steps or the sequence of actions is not important as long as this application remains operational. Furthermore, two or more steps or actions can be performed simultaneously.

[0029] The use of any and all instances or exemplary language such as “e.g.” or “include” in this document is intended merely to better illustrate the application and does not constitute a limitation on the scope of the application. No language in this specification should be construed as indicating that any unclaimed element is essential to the practice of this application.

[0030] Furthermore, the numerical ranges and parameters used to define this application are approximate values, and the relevant values ​​in the specific embodiments have been presented as precisely as possible. However, any numerical value inevitably contains standard deviations due to individual test methods. Therefore, unless otherwise explicitly stated, it should be understood that all ranges, quantities, values, and percentages used in this disclosure are modified with the word "approximately." Here, "approximately" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a specific value or range.

[0031] This application provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 50 to 70 parts polylactic acid, 10 to 30 parts polyε-caprolactone, 10 to 30 parts polypropylene carbonate, 30 to 50 parts functional masterbatch, and 0.1 to 0.5 parts antioxidant;

[0032] The functional masterbatch includes polylactic acid-modified nano silica-polypropylene carbonate graft and polylactic acid-modified nano silica-polyε-caprolactone graft.

[0033] The modified nano-silica is 4-phenylethynylphthalic anhydride modified nano-silica.

[0034] This application utilizes the bonding between silica and macromolecules to improve their dispersion performance, reduce the surface energy of the particles, decrease particle aggregation, and enhance their compatibility with organic components. Furthermore, the functional masterbatch enables polymer macromolecules such as PLA, PPC, and PCL to intertwine and form hydrogen bonds, improving the compatibility of components in the system and enhancing intermolecular interactions. This results in a tighter molecular chain arrangement, higher packing density, and smaller free volume, thereby reducing material permeability and increasing barrier properties. The polylactic acid composite material for packaging bottles meets the comprehensive requirements of products in terms of barrier properties, mechanical properties, heat resistance, and processing performance. The processing is environmentally friendly and easily industrialized.

[0035] The present application is further illustrated below with reference to embodiments. The scope of protection of the present application is not limited to the following embodiments.

[0036] Example 1

[0037] This embodiment provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 50 parts polylactic acid (PLA), 30 parts polypropylene carbonate (PPC), 20 parts poly(ε-caprolactone) (PCL), 0.2 parts antioxidant 1010, and 30 parts functional masterbatch.

[0038] The preparation method of the functional masterbatch includes:

[0039] Weigh out 100 grams After drying at 80℃, the solution was added to 300 mL of N-methylpyrrolidone solvent and ultrasonically dispersed for 1 hour. Then, it was added to a mixture of 50 g of phenylacetylene phthalic anhydride (PEPA) and 100 mL of N-methylpyrrolidone and stirred at 5000 r / min for 4 hours at 80℃. After natural cooling, washing, filtering, and drying, the final product was obtained. ;

[0040] 70 PLA, 30 PPC and 20 The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 5 kGy to obtain... ; 70 copies of PLA, 30 copies of PCL and 20 copies The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 5 kGy to obtain... ;

[0041] 100 copies 100 copies The grafted materials are mixed evenly and then melt-blended and extruded through an extruder at 190±10 ℃ to obtain functional masterbatch.

[0042] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0043] PLA, PPC, PCL, antioxidant 1010 and functional masterbatch are mixed evenly, melt-blended by a twin-screw extruder at 190±10 ℃, extruded, granulated and dried to obtain polylactic acid composite material for packaging bottles.

[0044] Table 1 shows the gel content and swelling degree of PLA-PCL grafts and PLA-PPC grafts under different irradiation doses.

[0045] Table 1

[0046]

[0047] Example 2

[0048] This embodiment provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 60 parts PLA, 25 parts PPC, 15 parts PCL, 0.2 parts antioxidant 1010, and 40 parts functional masterbatch.

[0049] The preparation method of the functional masterbatch includes:

[0050] Weigh out 100 grams After drying at 80℃, it was added to 300mL of N-methylpyrrolidone solvent and ultrasonically dispersed for 1 hour. Then, it was added to a mixer containing 25g of PEPA and 100mL of N-methylpyrrolidone and stirred at 5000r / min at 80℃ for 4 hours. After natural cooling, washing, filtering, and drying, the final product was obtained. ;

[0051] 70 PLA, 30 PPC and 25 The mixture is added to a twin-screw extruder, extruded, granulated, dried, and irradiated with an absorbed dose of 10 kGy to obtain... ; 70 copies of PLA, 30 copies of PCL and 25 copies The mixture is added to a twin-screw extruder, extruded, granulated, dried, and irradiated with an absorbed dose of 10 kGy to obtain... ;

[0052] 100 copies 100 copies The grafted materials are mixed evenly and then melt-blended and extruded through an extruder at 190±10 ℃ to obtain functional masterbatch.

[0053] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0054] PLA, PPC, PCL, antioxidant 1010 and functional masterbatch are mixed evenly, melt-blended by a twin-screw extruder at 190±10 ℃, extruded, granulated and dried to obtain polylactic acid composite material for packaging bottles.

[0055] Example 3

[0056] This embodiment provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 65 parts PLA, 10 parts PPC, 25 parts PCL, 0.2 parts antioxidant 1010, and 30 parts functional masterbatch.

[0057] The preparation method of the functional masterbatch includes:

[0058] Weigh out 100 grams After drying at 80℃, the solution was added to 300 mL of N-methylpyrrolidone solvent and ultrasonically dispersed for 1 hour. Then, it was added to a mixer containing 75 g of PEPA and 100 mL of N-methylpyrrolidone and stirred at 5000 r / min for 4 hours at 80℃. After natural cooling, washing, filtering, and drying, the final product was obtained. ;

[0059] 70 PLA, 30 PPC and 30 The mixture is added to a twin-screw extruder, extruded, granulated, dried, and irradiated with an absorbed dose of 10 kGy to obtain... ; 70 copies of PLA, 30 copies of PCL and 30 copies The mixture is added to a twin-screw extruder, extruded, granulated, dried, and irradiated with an absorbed dose of 10 kGy to obtain... ;

[0060] 100 copies 100 copies The grafted materials are mixed evenly and then melt-blended and extruded through an extruder at 190±10 ℃ to obtain functional masterbatch.

[0061] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0062] PLA, PPC, PCL, antioxidant 1010 and functional masterbatch are mixed evenly, melt-blended by a twin-screw extruder at 190±10 ℃, extruded, granulated and dried to obtain polylactic acid composite material for packaging bottles.

[0063] Example 4

[0064] This embodiment provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 70 parts PLA, 20 parts PPC, 10 parts PCL, 0.2 parts antioxidant 1010, and 30 parts functional masterbatch.

[0065] The preparation method of the functional masterbatch includes:

[0066] Weigh out 100 grams After drying at 80℃, it was added to 300 mL of N-methylpyrrolidone solvent and ultrasonically dispersed for 1 hour. Then, it was added to a mixer containing 50 g of PEPA and 100 mL of N-methylpyrrolidone and stirred at 5000 r / min for 4 hours at 80℃. After natural cooling, washing, filtering, and drying, the final product was obtained. ;

[0067] 70 PLA, 30 PPC and 25 The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 20 kGy to obtain... ; 70 copies of PLA, 30 copies of PCL and 25 copies The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 20 kGy to obtain... ;

[0068] 100 copies 100 copies The grafted materials are mixed evenly and then melt-blended and extruded through an extruder at 190±10 ℃ to obtain functional masterbatch.

[0069] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0070] PLA, PPC, PCL, antioxidant 1010 and functional masterbatch are mixed evenly, melt-blended by a twin-screw extruder at 190±10 ℃, extruded, granulated and dried to obtain polylactic acid composite material for packaging bottles.

[0071] Example 5

[0072] This embodiment provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 55 parts PLA, 15 parts PPC, 30 parts PCL, 0.2 parts antioxidant 1010, and 30 parts functional masterbatch.

[0073] The preparation method of the functional masterbatch includes:

[0074] Weigh out 100 grams After drying at 80℃, it was added to 300 mL of N-methylpyrrolidone solvent and ultrasonically dispersed for 1 hour. Then, it was added to a mixer containing 50 g of PEPA and 100 mL of N-methylpyrrolidone and stirred at 5000 r / min for 4 hours at 80℃. After natural cooling, washing, filtering, and drying, the final product was obtained. ;

[0075] 70 PLA, 30 PPC and 30 The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 25 kGy to obtain... ; 70 copies of PLA, 30 copies of PCL and 30 copies The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 25 kGy to obtain... ;

[0076] 100 copies 100 copies The grafted materials are mixed evenly and then melt-blended and extruded through an extruder at 190±10 ℃ to obtain functional masterbatch.

[0077] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0078] PLA, PPC, PCL, antioxidant 1010 and functional masterbatch are mixed evenly, melt-blended by a twin-screw extruder at 190±10 ℃, extruded, granulated and dried to obtain polylactic acid composite material for packaging bottles.

[0079] Example 6

[0080] This embodiment provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 70 parts PLA, 10 parts PPC, 20 parts PCL, 0.2 parts antioxidant 1010, and 40 parts functional masterbatch.

[0081] The preparation method of the functional masterbatch includes:

[0082] Weigh out 100 grams After drying at 80℃, it was added to 300 mL of N-methylpyrrolidone solvent and ultrasonically dispersed for 1 hour. Then, it was added to a mixer containing 50 g of PEPA and 100 mL of N-methylpyrrolidone and stirred at 5000 r / min for 4 hours at 80℃. After natural cooling, washing, filtering, and drying, the final product was obtained. ;

[0083] 70 PLA, 30 PPC and 25 The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 30 kGy to obtain... ; 70 copies of PLA, 30 copies of PCL and 25 copies The mixture is added to a twin-screw extruder, extruded, granulated, dried, and then irradiated with an absorbed dose of 30 kGy to obtain... ;

[0084] 100 copies 100 copies The grafted materials are mixed evenly and then melt-blended and extruded through an extruder at 190±10 ℃ to obtain functional masterbatch.

[0085] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0086] PLA, PPC, PCL, antioxidant 1010 and functional masterbatch are mixed evenly, melt-blended by a twin-screw extruder at 190±10 ℃, extruded, granulated and dried to obtain polylactic acid composite material for packaging bottles.

[0087] Comparative Example 1

[0088] This comparative example provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 70 parts PLA, 15 parts PPC, 15 parts PCL, and 0.2 parts antioxidant 1010.

[0089] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0090] PLA, PPC, PCL, and antioxidant 1010 are mixed, melt-blended using a twin-screw extruder at 190±10 ℃, extruded, granulated, and dried to obtain polylactic acid composite material for packaging bottles.

[0091] Comparative Example 2

[0092] This comparative example provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 70 parts PLA, 15 parts PCL, 15 parts PPC, and 20 parts... 0.2 parts antioxidant 1010.

[0093] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0094] PLA, PCL, PPC, The mixture of antioxidant 1010 and polylactic acid (PLA) is melt-blended using a twin-screw extruder at 190±10 ℃, extruded, granulated, and dried to obtain the PLA composite material for packaging bottles.

[0095] Comparative Example 3

[0096] This comparative example provides a polylactic acid composite material for packaging bottles, comprising, by weight parts: 70 parts PLA, 15 parts PCL, 15 parts PEPA, and 0.2 parts antioxidant 1010.

[0097] The preparation method of the polylactic acid composite material for packaging bottles includes:

[0098] PLA, PCL, PEPA, and antioxidant 1010 are mixed, melt-blended using a twin-screw extruder at 190±10℃, extruded, granulated, and dried to obtain polylactic acid composite material for packaging bottles.

[0099] Comparative Example 4

[0100] This comparative example provides a polylactic acid composite material for packaging bottles. The preparation method of the polylactic acid composite material for packaging bottles differs from that of Example 1 only in that the functional masterbatch includes only... .

[0101] Comparative Example 5

[0102] This comparative example provides a polylactic acid composite material for packaging bottles. The preparation method of the polylactic acid composite material for packaging bottles differs from that of Example 1 only in that the functional masterbatch includes only... .

[0103] The performance of the polylactic acid composite materials for packaging bottles provided in Examples 1-7 and Comparative Examples 1-5 was tested using the following methods:

[0104] Tensile strength and elongation at break: GB / T1042-2018;

[0105] Impact strength: GB / T 1043.1-2008;

[0106] Oxygen permeability: GB / T19789-2025;

[0107] Water vapor transmission rate: GB / T1037-2021.

[0108] The test results are shown in Table 2.

[0109] Table 2

[0110]

[0111] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in this application, based on the technical solution and application concept of this application, should be included within the scope of protection of this application.

Claims

1. A polylactic acid composite material for packaging bottles, characterized in that, It comprises, by weight parts: 50 to 70 parts polylactic acid, 10 to 30 parts poly-ε-caprolactone, 10 to 30 parts polypropylene carbonate, 30 to 50 parts functional masterbatch and 0.1 to 0.5 parts antioxidant; The functional masterbatch includes polylactic acid-modified nano silica-polypropylene carbonate graft and polylactic acid-modified nano silica-polyε-caprolactone graft. The modified nano-silica is 4-phenylethynylphthalic anhydride modified nano-silica.

2. The polylactic acid composite material for packaging bottles according to claim 1, characterized in that, The mass ratio of polylactic acid, polypropylene carbonate and modified nano silica in the polylactic acid-modified nano silica-polypropylene carbonate graft is 7:3:(2-3). The mass ratio of polylactic acid, poly-ε-caprolactone, and modified nano-silica in the polylactic acid-modified nano-silica-polyε-caprolactone graft is 7:3:(2-3).

3. The polylactic acid composite material for packaging bottles according to claim 1, characterized in that, The mass ratio of polylactic acid-modified nano silica-polypropylene carbonate graft to polylactic acid-modified nano silica-polyε-caprolactone graft in the functional masterbatch is 1:(0.8-1.2).

4. The polylactic acid composite material for packaging bottles according to claim 1, characterized in that, The mass ratio of nano-silica to 4-phenylethynyl phthalic anhydride in the 4-phenylethynyl phthalic anhydride modified nano-silica is 2:(0.5-1.5).

5. A method for preparing a polylactic acid composite material for packaging bottles, characterized in that, include: Polylactic acid, poly(ε-caprolactone), polypropylene carbonate, functional masterbatch and antioxidant are mixed and melt-extruded to obtain polylactic acid composite material for packaging bottles; The functional masterbatch includes polylactic acid-modified nano silica-polypropylene carbonate graft and polylactic acid-modified nano silica-polyε-caprolactone graft. The functional masterbatch is prepared by mixing polylactic acid-modified nano silica-polypropylene carbonate graft and polylactic acid-modified nano silica-polyε-caprolactone graft, followed by melt blending, extrusion granulation, and granulation to obtain the functional masterbatch. The modified nano-silica is 4-phenylethynylphthalic anhydride-modified nano-silica.

6. The preparation method according to claim 5, characterized in that, The preparation method of the polylactic acid-modified nano-silica-polypropylene carbonate graft includes: Polylactic acid, modified nano-silica, and polypropylene carbonate were melt-extruded, granulated, dried, and subjected to electron beam irradiation to obtain a polylactic acid-modified nano-silica-polypropylene carbonate graft. The mass ratio of polylactic acid, modified nano-silica, and polypropylene carbonate is 7:(2-3):3, and the absorbed dose of the electron beam radiation is 3KGy to 100KGy.

7. The preparation method according to claim 5, characterized in that, The preparation method of the polylactic acid-modified nano silica-polyε-caprolactone graft includes: Polylactic acid, modified nano-silica, and polyε-caprolactone were melt-extruded, granulated, dried, and subjected to electron beam irradiation to obtain a polylactic acid-modified nano-silica-polyε-caprolactone graft. The mass ratio of polylactic acid, modified nano silica, and poly(ε-caprolactone) is 7:(2-3):3, and the absorbed dose of the electron beam radiation is 3KGy to 100KGy.

8. The preparation method according to claim 5, characterized in that, The method for preparing the modified nano-silica includes: Modified nano-silica was obtained by mixing nano-silica with 4-phenylethynylphthalic anhydride.

9. The preparation method according to claim 8, characterized in that, The mass ratio of the nano-silica to 4-phenylethynylphthalic anhydride is 2:(0.5-1.5).

10. The preparation method according to claim 8, characterized in that, The mixing process further includes cooling, washing, filtering, and drying. The mixing temperature is between 60°C and 100°C, and the mixing time is between 4 hours and 6 hours.

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