Biodegradable hollow plate master batch and preparation process thereof

Abstract

The invention relates to a biodegradable hollow plate master batch and a preparation process thereof. The biodegradable hollow plate master batch is prepared from the following raw materials in parts by weight: 30-50 parts of a first monomer; 5-30 parts of a second monomer; 3-20 parts of a third monomer; 2 to 12 parts of biomass filler; the first monomer is one of a cyclohexane dibasic alcohol compound, a polyester copolymer, organic acid esters, aromatic polyester and the like, and the second monomer is one of a dicarboxylic acid compound, succinic acid and the like; the dicarboxylic acid compound comprises adipic acid and pimelic acid. According to the invention, a first monomer is a cyclohexanediyl alcohol compound, the cyclohexanediyl alcohol compound is 1, 4-cyclohexanedimethanol, and a second monomer is succinic acid; the third monomer is polyethylene glycol terephthalate and has the characteristics of transparency, toughness, chemical corrosion resistance and the like, the mechanical property, the degradation property and the environmental friendliness of the material are practically balanced, and a material-level solution is provided for sustainable development.

Description

Technical Field

[0001] This invention relates to the field of hollow board manufacturing technology, specifically to a biodegradable hollow board masterbatch and its preparation process. Background Technology

[0002] Hollow core board (also called hollow corrugated board, multi-wall board, double-wall board) is a lightweight (hollow structure), non-toxic, non-polluting, waterproof, shockproof, anti-aging, corrosion-resistant, and available in a variety of colors. Compared to cardboard products, hollow core board has advantages such as moisture resistance and corrosion resistance. Hollow core board is mainly used in various industries including electronics, packaging, machinery, light industry, postal services, food, pharmaceuticals, pesticides, home appliances, advertising, decoration, cultural products, optoelectronic technology, bioengineering, and pharmaceuticals. It is a new type of environmentally friendly packaging material, and hollow core board is mostly processed using masterbatch during its preparation.

[0003] However, most hollow core sheets currently on the market are made of thermoplastic polypropylene (PP) and polycarbonate. While these materials offer advantages such as moisture resistance, corrosion resistance, aging resistance, and flexible structural design, their use leads to their eventual obsolescence and ineffective recycling, resulting in a significant increase in environmental pressure and failing to meet energy sustainability requirements. Therefore, there is an urgent need to design a biodegradable hollow core sheet masterbatch and its preparation process to address these issues. Summary of the Invention

[0004] The purpose of this invention is to provide a biodegradable hollow board masterbatch and its preparation process to overcome the above-mentioned shortcomings in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A biodegradable hollow board masterbatch, the raw materials of which include the following components in parts by weight:

[0007] First monomer: 30-50 parts;

[0008] Second monomer: 5-30 parts;

[0009] Third monomer: 3-20 parts;

[0010] Biomass filler: 2-12 parts;

[0011] Modifying additives: 0.5-8 parts.

[0012] In a preferred embodiment of the present invention, the first monomer is one of cyclohexanediol compounds, polyester copolymers, organic acid esters, and aromatic polyesters.

[0013] In a preferred embodiment of the present invention, the second monomer is one of a dicarboxylic acid compound and succinic acid; the dicarboxylic acid compound includes adipic acid and pimelic acid.

[0014] In a preferred embodiment of the present invention, the third monomer is one of polyethylene terephthalate, alcohol compounds, and biocompatible materials.

[0015] In a preferred embodiment of the present invention, the biomass filler is one of acid-precipitated lignin, agricultural waste, straw, etc.

[0016] Lignin is dried, pulverized, and sieved to 100-2000 mesh;

[0017] Agricultural waste and straw are processed by extracting cellulose nanocrystals and combining them with the original leaf flocculent fibers, and then supplemented with surface modifiers, including ethyl cellulose and cyclodextrin.

[0018] In a preferred embodiment of the present invention, the modified additives include modified monomers, crosslinking agents, plasticizers, and modified catalysts.

[0019] A process for preparing a biodegradable hollow board masterbatch, comprising the aforementioned biodegradable hollow board masterbatch, includes the following steps:

[0020] S1. Raw material pretreatment: Different processes are used for different raw materials, including acid-precipitated lignin, agricultural waste, and straw.

[0021] S2. Mixing and melt blending, including high-speed mixing and melt extrusion, the pre-treated raw materials are added to the high-speed mixer according to the formula ratio; the mixed materials are then fed into a parallel twin-screw extruder for melt blending.

[0022] S3. Granulation and post-processing: Granulation: After the extruded melt is cooled and hardened, it is cut into pellets. The temperature of the cooling water needs to be precisely controlled to avoid deformation of the pellets.

[0023] Grading and Packaging: The dried masterbatch is graded according to particle size to remove oversized or undersized particles and ensure the stability of subsequent processing.

[0024] As a preferred embodiment of the present invention, the acid-precipitated lignin in the black liquor of papermaking needs to be dried, crushed and sieved to obtain a fine powder of 100-2000 mesh.

[0025] Agricultural waste and wheat straw are processed into natural fibers through multiple processes including washing, pressing, drying, alkali soaking, and alcohol washing. Then, the fibers are liquefied at 80-160℃ for 30-200 minutes, and the pH is adjusted to 6.5-7.5. A surface modifier is then added, which is a mixture of ethyl cellulose, cyclodextrin, and glycosyl glycerol. After crushing and sieving, cellulose nanocrystals are obtained.

[0026] As a preferred embodiment of the present invention

[0027] The high-speed mixer has a mixing time of 5-100 minutes and a speed of 50-600 r / min. The components are initially evenly dispersed, and a segmented mixing method is used.

[0028] The temperature settings for melt extrusion are divided into multiple temperature zones from the feed port to the die head, with each zone set between 130-200℃. The temperatures of the five temperature zones are set at 140-145-145-150-155℃ respectively, and the die head temperature is controlled at 150-200℃. The screw speed is 100-300 r / min.

[0029] In a preferred embodiment of the present invention, ultrasonic waves exceeding 20kHz cause water droplets on the surface of the material strip to cavitation and fall off, dripping onto the arc-shaped vibrating plate and atomizing, and then being quickly discharged through the de-fogging mechanism. The masterbatch after pelleting needs to be dried. A drying mechanism with a catapult plate can be used to throw and disperse the masterbatch, increasing the contact area with hot air. The drying temperature is 50-80℃.

[0030] In the above technical solution, the biodegradable hollow board masterbatch and its preparation process provided by the present invention have the following beneficial effects:

[0031] The first monomer is a cyclohexanediol compound, specifically 1,4-cyclohexanediethanol; the second monomer is succinic acid; and the third monomer is polyethylene terephthalate (PET). These materials possess properties such as transparency, toughness, and chemical resistance. The aforementioned materials achieve a practical balance in terms of mechanical properties, degradation performance, and environmental friendliness, providing a material-level solution for sustainable development. The biomass filler, derived from agricultural waste and straw, effectively utilizes agricultural waste to achieve material regeneration and effectively address the environmental problems caused by agricultural waste. The use of modifying agents accelerates the material's decomposition ability in the environment.

[0032] This masterbatch has mechanical properties approaching those of traditional plastics, while its advantages in degradation performance and environmental friendliness are unparalleled. With increasingly stringent environmental regulations and growing consumer environmental awareness, the penetration rate of this type of material in packaging, construction, agriculture, and other fields will continue to grow, driving the plastics industry towards green and sustainable development. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0034] Figure 1 This is a process diagram illustrating the preparation process of a biodegradable hollow plate masterbatch and its preparation process according to an embodiment of the present invention. Detailed Implementation

[0035] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0036] like Figure 1 As shown, a biodegradable hollow board masterbatch comprises the following components in parts by weight:

[0037] First monomer: 30-50 parts; Second monomer: 5-30 parts; Third monomer: 3-20 parts;

[0038] The first monomer is one of the following: cyclohexanediol compounds, polyester copolymers, organic acid esters, and aromatic polyesters; the second monomer is one of the following: dicarboxylic acid compounds and succinic acid; the dicarboxylic acid compounds include adipic acid and heptanoic acid; and the third monomer is one of the following: polyethylene terephthalate, alcohol compounds, and biocompatible materials.

[0039] Biomass filler: 2-12 parts; the biomass filler is one of acid-precipitated lignin, agricultural waste, straw, etc.; the lignin is dried, crushed, and sieved to 100-2000 mesh; the agricultural waste and straw are processed by extracting cellulose nanocrystals and compounding them with the original leaf flocculent fibers, and then supplemented with surface modifiers, including ethyl cellulose and cyclodextrin. Acid-precipitated lignin not only reduces material costs, but its polyphenol structure can also participate in the degradation reaction.

[0040] Modifying agents: 0.5-8 parts. Modifying agents include modifying monomers, crosslinking agents, plasticizers, and modified catalysts; they accelerate the decomposition of materials in the environment.

[0041] A process for preparing a biodegradable hollow board masterbatch, comprising the following steps:

[0042] S1. Raw material pretreatment: Different processes are used for different raw materials, including acid-precipitated lignin, agricultural waste, and straw. Acid-precipitated lignin in papermaking black liquor needs to be dried, crushed, and sieved to obtain fine powder of 100-2000 mesh. Agricultural waste and wheat straw are processed into natural fibers through multiple processes such as washing, pressing, drying, alkali soaking, and alcohol washing. Then, they are liquefied at 80-160℃ for 30-200 minutes, and the pH is adjusted to 6.5-7.5 before adding a surface modifier. The surface modifier is a mixture of ethyl cellulose, cyclodextrin, and glycosyl glycerol. After crushing and sieving, cellulose nanocrystals are obtained.

[0043] S2. Mixing and melt blending, including high-speed mixing and melt extrusion, involves adding pre-treated raw materials to a high-speed mixer according to the formula ratio. The mixed material then enters a parallel twin-screw extruder for melt blending. The high-speed mixing time is 5-100 minutes, with the speed controlled at 50-600 r / min, ensuring initial uniform dispersion of components using a segmented mixing method. The melt extrusion temperature is set in multiple zones from the feed port to the die head, ranging from 130-200℃. The five temperature zones are set at 140-145-145-150-155℃, with the die head temperature controlled at 150-200℃ and the screw speed at 100-300 r / min. This gentle heating strategy avoids excessive degradation of biopolymer chains while ensuring sufficient melt flowability. Parallel twin-screw extruders are more suitable for processing masterbatches with high filler content. Their kneading block design provides stronger shear force, promoting melt uniformity. The screw length-to-diameter ratio is typically chosen to extend the residence time and improve the mixing effect.

[0044] S3. Granulation and post-processing: Granulation: After the extruded melt is cooled and hardened, it is cut into pellets. The temperature of the cooling water needs to be precisely controlled to avoid deformation of the pellets.

[0045] Grading and Packaging: The dried masterbatch is graded according to particle size to remove excessively large or small particles, ensuring stability in subsequent processing. Ultrasonic waves exceeding 20kHz cause cavitation effects on the surface of the pellets, causing water droplets to detach and drip onto an arc-shaped vibrating plate, where they are atomized and then quickly discharged through an exhaust mechanism. The masterbatch after pelleting needs to be dried using a drying mechanism with a catapult plate to throw and disperse the masterbatch, increasing the contact area with hot air. The drying temperature is 50-80℃.

[0046] Example 1

[0047] A process for preparing a biodegradable hollow board masterbatch includes a biodegradable hollow board masterbatch whose raw materials comprise the following components by weight: First monomer: 50 parts; Second monomer: 28 parts; Third monomer: 20 parts; The first monomer is a cyclohexanediol compound, specifically 1,4-cyclohexanediethanol; the second monomer is succinic acid; The third monomer is polyethylene terephthalate, possessing properties such as transparency, toughness, and chemical resistance. Biomass filler: 10 parts; The biomass filler is agricultural waste or straw. Modifying agents: 2 parts; The modifying agents include modifying monomers, crosslinking agents, plasticizers, and modifying catalysts.

[0048] Includes the following steps:

[0049] S1. Raw material pretreatment: Different processes are used for different raw materials, including acid-precipitated lignin, agricultural waste, and straw. Acid-precipitated lignin in papermaking black liquor needs to be dried, crushed, and sieved to obtain a fine powder of 1000 mesh. Agricultural waste and wheat straw are processed into natural fibers through multiple processes such as washing, pressing, drying, alkali soaking, and alcohol washing. Then, they are liquefied at 120℃ for 120 minutes, and after adjusting the pH to 7.0, a surface modifier is added. The surface modifier is a mixture of ethyl cellulose, cyclodextrin, and glycosyl glycerol. After crushing and sieving, cellulose nanocrystals are obtained.

[0050] S2. Mixing and melt blending, including high-speed mixing and melt extrusion, the pre-treated raw materials are added to the high-speed mixer according to the formula ratio; the mixed materials are fed into the parallel twin-screw extruder for melt blending; the high-speed mixing time is 60 minutes, the speed is controlled at 300 r / min, the components are initially uniformly dispersed, and segmented mixing is adopted; the temperature setting of melt extrusion is divided into multiple temperature zones from the feed port to the die head, and the temperatures of the five temperature zones are set to 140-145-145-150-155℃ respectively, and the screw speed is 230 r / min.

[0051] S3. Granulation and Post-processing: Granulation: After the extruded melt is cooled and hardened, it is granulated. The cooling water temperature needs to be precisely controlled to avoid deformation of the pellets. Grading and Packaging: The dried masterbatch is graded according to particle size to remove excessively large or small particles, ensuring the stability of subsequent processing. Ultrasonic waves exceeding 20kHz cause water droplets on the surface of the pellets to cavitate and fall off, dripping onto the arc-shaped vibrating plate and atomizing before being quickly discharged through the de-fogging mechanism. The granulated masterbatch needs to be dried. A drying mechanism with a catapult plate can be used to throw and disperse the masterbatch upwards, increasing the contact area with hot air. The drying temperature is 60℃.

[0052] Example 2

[0053] A process for preparing a biodegradable hollow fiberboard masterbatch includes a biodegradable hollow fiberboard masterbatch whose raw materials comprise the following components by weight: First monomer: 50 parts; Second monomer: 23 parts; Third monomer: 15 parts; The first monomer is a cyclohexanediol compound, the second monomer is succinic acid, and the third monomer is polyethylene terephthalate. Biomass filler: 10 parts; The biomass filler is agricultural waste or straw. Modifying agents: 2 parts, The modifying agents include modifying monomers, crosslinking agents, plasticizers, and modifying catalysts.

[0054] Includes the following steps:

[0055] S1. Raw material pretreatment: Different processes are used for different raw materials, including acid-precipitated lignin, agricultural waste, and straw. Acid-precipitated lignin in papermaking black liquor needs to be dried, crushed, and sieved to obtain a fine powder of 1000 mesh. Agricultural waste and wheat straw are processed into natural fibers through multiple processes such as washing, pressing, drying, alkali soaking, and alcohol washing. Then, they are liquefied at 120℃ for 120 minutes, and after adjusting the pH to 7.0, a surface modifier is added. The surface modifier is a mixture of ethyl cellulose, cyclodextrin, and glycosyl glycerol. After crushing and sieving, cellulose nanocrystals are obtained.

[0056] S2. Mixing and melt blending, including high-speed mixing and melt extrusion, the pre-treated raw materials are added to the high-speed mixer according to the formula ratio; the mixed materials are fed into the parallel twin-screw extruder for melt blending; the high-speed mixing time is 60 minutes, the speed is controlled at 300 r / min, the components are initially uniformly dispersed, and segmented mixing is adopted; the temperature setting of melt extrusion is divided into multiple temperature zones from the feed port to the die head, and the temperatures of the five temperature zones are set to 140-145-145-150-155℃ respectively, and the screw speed is 230 r / min.

[0057] S3. Granulation and Post-processing: Granulation: After the extruded melt is cooled and hardened, it is granulated. The cooling water temperature needs to be precisely controlled to avoid deformation of the pellets. Grading and Packaging: The dried masterbatch is graded according to particle size to remove excessively large or small particles, ensuring the stability of subsequent processing. Ultrasonic waves exceeding 20kHz cause water droplets on the surface of the pellets to cavitate and fall off, dripping onto the arc-shaped vibrating plate and atomizing before being quickly discharged through the de-fogging mechanism. The granulated masterbatch needs to be dried. A drying mechanism with a catapult plate can be used to throw and disperse the masterbatch upwards, increasing the contact area with hot air. The drying temperature is 60℃.

[0058] Example 3

[0059] A process for preparing a biodegradable hollow fiberboard masterbatch includes a biodegradable hollow fiberboard masterbatch, the raw materials of which include the following components by weight: a first monomer: 50 parts; a second monomer: 18 parts; a third monomer: 20 parts; the first monomer is a cyclohexanediol compound, the second monomer is succinic acid, and the third monomer is polyethylene terephthalate. Biomass filler: 10 parts; the biomass filler is agricultural waste or straw. Modifying agents: 2 parts, the modifying agents including modifying monomers, crosslinking agents, plasticizers, and modifying catalysts.

[0060] Includes the following steps:

[0061] S1. Raw material pretreatment: Different processes are used for different raw materials, including acid-precipitated lignin, agricultural waste, and straw. Acid-precipitated lignin in papermaking black liquor needs to be dried, crushed, and sieved to obtain a fine powder of 1000 mesh. Agricultural waste and wheat straw are processed into natural fibers through multiple processes such as washing, pressing, drying, alkali soaking, and alcohol washing. Then, they are liquefied at 120℃ for 120 minutes, and after adjusting the pH to 7.0, a surface modifier is added. The surface modifier is a mixture of ethyl cellulose, cyclodextrin, and glycosyl glycerol. After crushing and sieving, cellulose nanocrystals are obtained.

[0062] S2. Mixing and melt blending, including high-speed mixing and melt extrusion, the pre-treated raw materials are added to the high-speed mixer according to the formula ratio; the mixed materials are fed into the parallel twin-screw extruder for melt blending; the high-speed mixing time is 60 minutes, the speed is controlled at 300 r / min, the components are initially uniformly dispersed, and segmented mixing is adopted; the temperature setting of melt extrusion is divided into multiple temperature zones from the feed port to the die head, and the temperatures of the five temperature zones are set to 140-145-145-150-155℃ respectively, and the screw speed is 230 r / min.

[0063] S3. Granulation and Post-processing: Granulation: After the extruded melt is cooled and hardened, it is granulated. The cooling water temperature needs to be precisely controlled to avoid deformation of the pellets. Grading and Packaging: The dried masterbatch is graded according to particle size to remove excessively large or small particles, ensuring the stability of subsequent processing. Ultrasonic waves exceeding 20kHz cause water droplets on the surface of the pellets to cavitate and fall off, dripping onto the arc-shaped vibrating plate and atomizing before being quickly discharged through the de-fogging mechanism. The granulated masterbatch needs to be dried. A drying mechanism with a catapult plate can be used to throw and disperse the masterbatch upwards, increasing the contact area with hot air. The drying temperature is 60℃.

[0064] The masterbatches prepared in Examples 1, 2, and 3 demonstrate that biodegradable hollow board masterbatches exhibit balanced mechanical properties. In Example 2, the first monomer comprised 50 parts; the second monomer 23 parts; and the third monomer 15 parts. The first monomer was a cyclohexanediol compound, the second monomer was succinic acid, and the third monomer was polyethylene terephthalate. The biomass filler comprised 10 parts; the biomass filler consisted of agricultural waste and straw. Modifying agents: 2 parts. The modifying agents include modified monomers, crosslinking agents, plasticizers, and modified catalysts. The tensile strength of the composite masterbatch material can reach 25-35 MPa, the elongation at break exceeds 200%, and the flexural modulus is about 1.5-2 GPa, which is sufficient to meet the strength requirements of most packaging and construction hollow boards. It further improves toughness, so that the impact resistance of the composite material is improved by more than 30% while maintaining rigidity. It not only improves the chemical resistance of the product, but also increases the heat sealing strength by 2-3 times, broadening the application of hollow boards in the field of high-temperature packaging (58±2℃, humidity 50-60%). More than 90% can be degraded within 6 months.

[0065] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A biodegradable hollow board masterbatch, characterized in that, Its raw materials include the following components in parts by weight: First monomer: 30-50 parts; Second monomer: 5-30 parts; Third monomer: 3-20 parts; Biomass filler: 2-12 parts; Modifying additives: 0.5-8 parts.

2. The biodegradable hollow plate masterbatch according to claim 1, characterized in that, The first monomer is one of the following: cyclohexanediol compounds, polyester copolymers, organic acid esters, and aromatic polyesters.

3. The biodegradable hollow plate masterbatch according to claim 1, characterized in that, The second monomer is one of dicarboxylic acid compounds and succinic acid, etc.; dicarboxylic acid compounds include adipic acid and pimelic acid.

4. The biodegradable hollow plate masterbatch according to claim 1, characterized in that, The third monomer is one of polyethylene terephthalate, alcohol compounds, and biocompatible materials.

5. The biodegradable hollow plate masterbatch according to claim 1, characterized in that, The biomass filler is one of acid-precipitated lignin, agricultural waste, straw, etc. Lignin is dried, pulverized, and sieved to 100-2000 mesh; Agricultural waste and straw are processed by extracting cellulose nanocrystals and combining them with the original leaf flocculent fibers, and then supplemented with surface modifiers, including ethyl cellulose and cyclodextrin.

6. The biodegradable hollow plate masterbatch according to claim 1, characterized in that, The modified additives include modified monomers, crosslinking agents, plasticizers, and modified catalysts.

7. A process for preparing a biodegradable hollow board masterbatch, comprising the biodegradable hollow board masterbatch according to any one of claims 1-6, characterized in that, Includes the following steps: S1. Raw material pretreatment: Different processes are used for different raw materials, including acid-precipitated lignin, agricultural waste, and straw. S2. Mixing and melt blending, including high-speed mixing and melt extrusion, involves adding pre-treated raw materials to a high-speed mixer according to the formula ratio; the mixed materials are then fed into a parallel twin-screw extruder for melt blending. S3. Granulation and post-processing: Granulation: After the extruded melt is cooled and hardened, it is cut into pellets. The temperature of the cooling water needs to be precisely controlled to avoid deformation of the pellets. Grading and Packaging: The dried masterbatch is graded according to particle size to remove oversized or undersized particles and ensure the stability of subsequent processing.

8. The biodegradable hollow plate masterbatch according to claim 7, characterized in that, The acid-precipitated lignin in papermaking black liquor needs to be dried, crushed, and sieved to obtain a fine powder of 100-2000 mesh. Agricultural waste and wheat straw are processed into natural fibers through multiple processes including washing, pressing, drying, alkali soaking, and alcohol washing. Then, the fibers are liquefied at 80-160℃ for 30-200 minutes, and the pH is adjusted to 6.5-7.

5. A surface modifier is then added, which is a mixture of ethyl cellulose, cyclodextrin, and glycosyl glycerol. After crushing and sieving, cellulose nanocrystals are obtained.

9. The biodegradable hollow plate masterbatch according to claim 7, characterized in that, The high-speed mixer has a mixing time of 5-100 minutes and a speed of 50-600 r / min. The components are initially evenly dispersed, and a segmented mixing method is used. The temperature settings for melt extrusion are divided into multiple temperature zones from the feed port to the die head, with each zone set between 130-200℃. The temperatures of the five temperature zones are set at 140-145-145-150-155℃ respectively, and the die head temperature is controlled at 150-200℃. The screw speed is 100-300 r / min.

10. The biodegradable hollow plate masterbatch according to claim 7, characterized in that, Ultrasonic waves exceeding 20kHz cause water droplets on the surface of the pellets to cavitate and fall off, dripping onto the arc-shaped vibrating plate and atomizing. The droplets are then quickly discharged through the de-fogging mechanism. The masterbatch after pelleting needs to be dried. A drying mechanism with a catapult plate can be used to throw and disperse the masterbatch, increasing the contact area with hot air. The drying temperature is 50-80℃.

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