Degradable environment-friendly fiber table board and preparation method thereof

Abstract

The invention relates to the technical field of preparation of degradable table plates, in particular to a degradable environment-friendly fiber table plate and a preparation method thereof.The degradable environment-friendly fiber table plate comprises a base plate layer, and the base plate layer is sequentially provided with a damp-proof sealing layer, a force bearing reinforcing layer, a core layer and an outer reinforcing layer from bottom to top; the top of the base plate layer is coated with the functional coating, and the functional coating is sequentially provided with a base plate surface treatment layer, an antistatic layer and a surface sealing coating from bottom to top; the film covering layer is adhered to the top of the functional coating, and the film covering layer is sequentially provided with a functional covering film and a peelable protective film from bottom to top. The substrate layer is constructed through the degradable natural fibers and the bio-based resin, moisture erosion is blocked through the moisture-proof sealing layer, stable static dissipation and no electromagnetic interference are achieved through the ionic liquid antistatic layer, the high X-ray transmittance is guaranteed through the biodegradable conductive layer with the surface coated with the film, the whole material system can be completely biodegraded after being discarded, and the cost is low. The device is widely applied to electronic laboratories and medical environments.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of degradable table board preparation, in particular to a degradable environment-friendly fiber table board and a preparation method thereof. BACKGROUND

[0002] The fiber table board is a flat plate component with fiber reinforced composite material as the core structure, which is formed by compounding and curing high-strength fibers and resin matrix, and has the advantages of lightweight, high rigidity and functional designability, and is widely used in medical, laboratory, industrial and other table surface scenes with special requirements for material performance.

[0003] Generally, the traditional fiber table board usually uses synthetic fibers such as carbon fibers or glass fibers which are not degradable, and petroleum-based resins such as epoxy resin and unsaturated polyester to form a composite structure. The structure is usually a single solid laminated board or a sandwich board, and the surface treatment relies on fluorine-containing coating or metal plating film to realize the functions of anti-fouling and anti-static. The overall material system is non-renewable and difficult to recycle.

[0004] However, in the electronic laboratory and other environments sensitive to static electricity, the anti-static layer of the traditional fiber table board usually relies on metal particles or carbon black filling, which is easy to fail due to wear and tear and interfere with electromagnetic equipment. In the medical imaging field, although the carbon fiber table board has X-ray transmittance, it cannot be naturally degraded after being discarded and forms permanent pollution. The manufacturing process uses toxic solvents, releases volatile organic compounds and harms the health of operators, and the high-cost synthetic materials further restrict the popularization and application.

[0005] Therefore, the present application provides a degradable environment-friendly fiber table board and a preparation method thereof to solve the above technical problems. SUMMARY

[0006] The present application aims to provide a degradable environment-friendly fiber table board and a preparation method thereof to solve the problems mentioned in the background.

[0007] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0008] The present application provides a degradable environment-friendly fiber table board, which comprises:

[0009] The base plate layer is sequentially provided with a moisture-proof sealing layer, a force-enhancing layer, a core layer and an outer enhancing layer from bottom to top.

[0010] The moisture-proof sealing layer is a modified polylactic acid film composed of a polylactic acid matrix with a thickness of ≥0.3mm, 5-8wt% of a grafted modified maleic anhydride compatibilizer and 3-5wt% of nano-montmorillonite with a particle size of <50nm; the force-enhancing layer is a unidirectional flax fiber and a bio-based resin pre-impregnated material; the core layer is a honeycomb core material; and the outer enhancing layer is a plain weave hemp fiber and a bio-based resin pre-impregnated material.

[0011] A functional coating is applied to the top of the substrate layer, and the functional coating is provided with a substrate surface treatment layer, an antistatic layer and a surface sealing coating from bottom to top.

[0012] The substrate surface treatment layer is a bio-based epoxy primer composed of cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent, and fumed silica. The mass ratio of cashew phenol glycidyl ether epoxy resin: polysaccharide anhydride curing agent: fumed silica is 40:10:1, and the fumed silica has a particle size of 12 nm. The antistatic layer is an ion-conductive waterborne coating composed of polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water. The mass ratio of imidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water is 15:5:3:77, and the diameter of the nanocellulose whiskers is 5-20 nm. The surface sealing coating is a bio-based polyurethane topcoat composed of castor oil-based polyester polyol, hexamethylene diisocyanate trimer, and nano-alumina, with a mass ratio of castor oil-based polyester polyol, hexamethylene diisocyanate trimer, and nano-alumina of 6:4:1. The OH value of the castor oil-based polyester polyol is 110 mg KOH / g, and the nano-alumina has a particle size of 50 nm.

[0013] A coating layer is bonded to the top of a functional coating layer, and the coating layer is provided with a functional coating and a peelable protective film from bottom to top.

[0014] The functional coating substrate is polybutylene adipate / terephthalate, and its surface is grafted with a poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate conductive layer via plasma activation, with a sheet resistance ≤10. 6 Ω / sq, thickness 50μm; the peelable protective film is a polyhydroxybutyrate film with a thickness of 25μm.

[0015] Preferably, in the unidirectional flax fiber and bio-based resin pre-impregnated material of the load-bearing reinforcement layer, the unidirectional flax fiber is a unidirectional layup of long flax fiber bundles with a fiber volume fraction ≥55% that has been treated with alkali and silane coupling agent KH550, and the bio-based resin is an epoxy soybean oil acrylate photocurable resin, which contains 0.5 wt% phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide photoinitiator.

[0016] Preferably, the honeycomb core material of the external reinforcement is a polybutylene succinate resin solution with a solid content of 40% impregnated with 100% recycled kraft paper as raw material, and a density ≥80 kg / m³. 3 With a coating amount of 1.5 g / m 2Surface treatment with polyethyleneimine crosslinking agent.

[0017] Preferably, the outer reinforcing layer is a plain-weave hemp fiber and a bio-based resin pre-impregnated material with an acetylation treatment weight of 200 g / m². 2 Plain-weave hemp fiber fabric prepreg material with thermoplastic resin of furanyl dicarboxylate copolymer.

[0018] This invention also proposes a method for preparing a biodegradable and environmentally friendly fiber tabletop, comprising the following steps:

[0019] S1. Prepare a moisture-proof sealing layer, a load-bearing reinforcement layer, a core layer and an outer reinforcement layer, and stack the four layers in sequence and hot press them to form a substrate layer;

[0020] S2. After cleaning the substrate layer obtained in S1, spray a mixture of cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent and fumed silica to cure and form a substrate surface treatment layer. Then roll-coat a mixture of polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers and deionized water to form an antistatic layer. Spray a mixture of castor oil-based polyester polyol, hexamethylene diisocyanate trimer and nanoalumina to cure and form a surface sealing coating.

[0021] S3. A functional coating and a peelable protective film are sequentially laminated onto the substrate layer after the S2 coating is applied to form a coating layer. After roll pressing, a biodegradable and environmentally friendly fiber tabletop is obtained.

[0022] Preferably, the substrate layer fabrication process includes the following steps:

[0023] A1. Moisture-proof sealing layer forming: Polylactic acid granules are premixed with 5-8wt% maleic anhydride graft compatibilizer and 3-5wt% nano-montmorillonite with a particle size <50nm; then the mixture is fed into a twin-screw extruder for melt blending, and the extrusion temperature is controlled at 170-180℃; the melt is then cast through a T-die to a 40℃ mirror roller to form a film, and finally a film with a thickness ≥0.3mm is produced and wound up for later use;

[0024] A2. Preparation of prepreg for load-bearing reinforcement layer: Long flax fiber bundles were immersed in 5wt% NaOH solution for 60 min, washed with water, and then transferred to 1wt% KH550 silane coupling agent ethanol solution for impregnation; subsequently dried in an oven at 110℃; then the fiber bundles were unidirectionally laid up at a volume fraction ≥55%, and drawn through a 50℃ epoxy soybean oil acrylate resin bath for impregnation, the resin containing 0.5wt% TPO photoinitiator; finally, the mixture was subjected to a 365nm wavelength, 300mW / cm 2 Pre-curing with high-intensity ultraviolet light to produce semi-cured sheets;

[0025] A3. Core Layer Treatment: Hexagonal honeycomb core material is made from 100% recycled kraft paper, with each unit having a side length of 6mm; it is immersed in 40% PBS resin solution for 120s; then the solution is drained and dried in an 80℃ hot air oven for 30min; finally, PEI crosslinking agent is roller-coated, with the coating amount controlled at 1.5g / m². 2 ;

[0026] A4. Preparation of outer reinforcement layer prepreg: 200g / m 2 Plain hemp fibers are arranged in an acetylation environment with acetic anhydride vapor to control the weight gain rate at 8-10%; then the fiber cloth is fed into a two-roller thermal laminator and double-sided laminated with MFI=15g / 10min PBF resin film at a roller temperature of 150℃.

[0027] A5. Substrate lamination molding: The substrate is laminated in the following order: moisture-proof sealing layer, load-bearing reinforcement layer prepreg, core layer, and outer reinforcement layer prepreg; then it is fed into a hot press and pressed at 160℃ and 0.8MPa for 20 minutes; finally, it is cooled to 60℃ and demolded.

[0028] Preferably, the functional coating preparation process includes the following steps:

[0029] B1. Substrate surface treatment layer coating: Weigh cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent, and fumed silica at a mass ratio of 40:10:1; stir at 3000 rpm for 15 min using a high-speed disperser; then spray the coating onto the substrate surface, controlling the wet film thickness to 80 μm; finally, perform step curing: 80℃ / 30 min to 120℃ / 60 min;

[0030] B2. Antistatic layer coating: Polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water were then weighed according to a mass ratio of 15:5:3:77; ultrasonically dispersed at 500W for 30min; then rolled onto the upper surface of the substrate layer, controlling the wet film thickness to 50μm; finally dried with hot air at 60℃ for 20min.

[0031] B3. Surface sealing coating construction: Finally, mix castor oil polyester polyol with OH value of 110mgKOH / g, hexamethylene diisocyanate trimer, and nano alumina at a mass ratio of 6:4:1; spray it onto the upper surface of the substrate layer under high pressure and control the wet film thickness to 100μm; finally, perform two-stage curing from 25℃ / 24h to 80℃ / 2h.

[0032] Preferably, the coating layer preparation process includes the following steps:

[0033] C1. Functional coating process: A 50 μm PBAT film was placed in a plasma chamber and treated at 300 W and 20 Pa for 120 s; then EDOT monomer was vapor-deposited and PSS solution was simultaneously atomized and sprayed in; FeCl3 vapor catalyst was introduced and reacted at 60 °C for 30 min to form a PEDOT:PSS layer with a sheet resistance ≤106 Ω / sq on the substrate after the functional coating was applied.

[0034] C2. Preparation of peelable protective film: Coat the surface of a 25μm PHB film with an acrylic-itaconic ester adhesive with a Tg of -45℃; control the adhesive layer thickness to 10μm; and then cure at 80℃ for 48h.

[0035] C3. Coating layer lamination: Finally, with the functional coated conductive layer facing down, it is laminated with the functional coating using a 100℃ hot roller press at a speed of 0.3MPa and 1m / min; then the protective film adhesive side is bonded to the PBAT substrate side and rolled at room temperature.

[0036] Compared with the prior art, the beneficial effects of the present invention are:

[0037] This invention constructs a substrate layer using biodegradable natural fibers and bio-based resin, with a moisture-proof sealing layer to block moisture erosion, an ionic liquid antistatic layer to achieve stable static dissipation without electromagnetic interference, and a biodegradable conductive layer on the surface to ensure high X-ray transmittance. The entire material system is completely biodegradable after disposal, avoiding environmental pollution. It can be widely used in electronic laboratories and medical environments, solving the solid waste problem caused by replacing petroleum-based composite materials with non-degradable traditional fiber tabletops. It innovates the ionic conductive antistatic mechanism, overcoming the equipment interference and insufficient wear resistance caused by traditional metal fillers. Furthermore, the low-temperature molding process eliminates the use of toxic solvents, achieving zero pollution in the manufacturing process, and providing a sustainable solution for precision laboratories and green healthcare. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0039] I. Materials:

[0040] It should be noted that, unless otherwise stated, all biodegradable and environmentally friendly fiber tabletop materials used in this invention are commercially available.

[0041] This invention proposes a biodegradable and environmentally friendly fiber tabletop, comprising:

[0042] The substrate layer is provided with a moisture-proof sealing layer, a load-bearing reinforcement layer, a core layer and an outer reinforcement layer from bottom to top.

[0043] The moisture-proof sealing layer is a modified polylactic acid film composed of a polylactic acid matrix with a thickness of ≥0.3mm, 5-8wt% of grafted modified maleic anhydride compatibilizer, and 3-5wt% nano-montmorillonite with a particle size of <50nm; the load-bearing reinforcement layer is a unidirectional flax fiber and a bio-based resin prepreg material; the core layer is a honeycomb core material; and the outer reinforcement layer is a plain-weave hemp fiber and a bio-based resin prepreg material.

[0044] The functional coating is applied to the top of the substrate layer. The functional coating consists of a substrate surface treatment layer, an antistatic layer, and a surface sealing coating, arranged sequentially from bottom to top.

[0045] The substrate surface treatment layer is a bio-based epoxy primer composed of cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent, and fumed silica. The mass ratio of cashew phenol glycidyl ether epoxy resin to polysaccharide anhydride curing agent to fumed silica is 40:10:1, and the fumed silica particle size is 12nm. The antistatic layer is an ion-conductive waterborne coating composed of polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water. The mass ratio of methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water is 15:5:3:77, and the diameter of the nanocellulose whiskers is 5-20 nm. The surface sealing coating is a bio-based polyurethane topcoat composed of castor oil-based polyester polyol, hexamethylene diisocyanate trimer, and nano-alumina. The mass ratio of castor oil-based polyester polyol, hexamethylene diisocyanate trimer, and nano-alumina is 6:4:1. The OH value of castor oil-based polyester polyol is 110 mg KOH / g, and the particle size of nano-alumina is 50 nm.

[0046] A coating layer is bonded to the top of the functional coating layer. The coating layer consists of a functional coating and a peelable protective film from bottom to top.

[0047] The functional coating substrate is poly(butylene adipate) / terephthalate, and its surface is grafted with a poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate conductive layer through plasma activation, with a sheet resistance ≤10. 6 Ω / sq, thickness 50μm; the peelable protective film is a polyhydroxybutyrate film, thickness 25μm.

[0048] It should also be noted that in the unidirectional flax fiber and bio-based resin prepreg material of the load-bearing reinforcement layer, the unidirectional flax fiber is a unidirectional layup of long flax fiber bundles with a fiber volume fraction ≥55% that has been treated with alkali and silane coupling agent KH550. The bio-based resin is an epoxy soybean oil acrylate photocurable resin, which contains 0.5wt% phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide photoinitiator.

[0049] It should also be noted that the honeycomb core material of the external reinforcement is made from 100% recycled kraft paper, impregnated with polybutylene succinate resin solution with a solid content of 40% and a density ≥80kg / m³. 3 With a coating amount of 1.5 g / m 2 Surface treatment with polyethyleneimine crosslinking agent.

[0050] It should also be noted that the outer reinforcing layer is a plain-weave hemp fiber and bio-based resin pre-impregnated material with an acetylation treatment weight of 200 g / m². 2 Plain-weave hemp fiber fabric prepreg material with thermoplastic resin of furanyl dicarboxylate copolymer.

[0051] II. Process:

[0052] This invention also proposes a method for preparing a biodegradable and environmentally friendly fiber tabletop, comprising the following steps:

[0053] S1. Prepare a moisture-proof sealing layer, a load-bearing reinforcement layer, a core layer and an outer reinforcement layer, and stack the four layers in sequence and hot press them to form a substrate layer;

[0054] S2. After cleaning the substrate layer obtained in S1, spray a mixture of cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent and fumed silica to cure and form a substrate surface treatment layer. Then roll-coat a mixture of polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers and deionized water to form an antistatic layer. Spray a mixture of castor oil-based polyester polyol, hexamethylene diisocyanate trimer and nanoalumina to cure and form a surface sealing coating.

[0055] S3. A functional coating and a peelable protective film are sequentially laminated onto the substrate layer after the S2 coating is applied to form a coating layer. After roll pressing, a biodegradable and environmentally friendly fiber tabletop is obtained.

[0056] It should also be noted that the substrate layer fabrication process includes the following steps:

[0057] A1. Moisture-proof sealing layer forming: Polylactic acid granules are premixed with 5-8wt% maleic anhydride graft compatibilizer and 3-5wt% nano-montmorillonite with a particle size <50nm; then the mixture is fed into a twin-screw extruder for melt blending, and the extrusion temperature is controlled at 170-180℃; the melt is then cast through a T-die to a 40℃ mirror roller to form a film, and finally a film with a thickness ≥0.3mm is produced and wound up for later use;

[0058] A2. Preparation of prepreg for load-bearing reinforcement layer: Long flax fiber bundles were immersed in 5wt% NaOH solution for 60 min, washed with water, and then transferred to 1wt% KH550 silane coupling agent ethanol solution for impregnation; subsequently dried in an oven at 110℃; then the fiber bundles were unidirectionally laid up at a volume fraction ≥55%, and drawn through a 50℃ epoxy soybean oil acrylate resin bath for impregnation, the resin containing 0.5wt% TPO photoinitiator; finally, the mixture was subjected to a 365nm wavelength, 300mW / cm 2 Pre-curing with high-intensity ultraviolet light to produce semi-cured sheets;

[0059] A3. Core Layer Treatment: Hexagonal honeycomb core material is made from 100% recycled kraft paper, with each unit having a side length of 6mm; it is immersed in 40% PBS resin solution for 120s; then the solution is drained and dried in an 80℃ hot air oven for 30min; finally, PEI crosslinking agent is roller-coated, with the coating amount controlled at 1.5g / m². 2 ;

[0060] A4. Preparation of outer reinforcement layer prepreg: 200g / m 2 Plain hemp fibers are arranged in an acetylation environment with acetic anhydride vapor to control the weight gain rate at 8-10%; then the fiber cloth is fed into a two-roller thermal laminator and double-sided laminated with MFI=15g / 10min PBF resin film at a roller temperature of 150℃.

[0061] A5. Substrate lamination molding: The substrate is laminated in the following order: moisture-proof sealing layer, load-bearing reinforcement layer prepreg, core layer, and outer reinforcement layer prepreg; then it is fed into a hot press and pressed at 160℃ and 0.8MPa for 20 minutes; finally, it is cooled to 60℃ and demolded.

[0062] It should also be noted that the functional coating preparation process includes the following steps:

[0063] B1. Substrate surface treatment layer coating: Weigh cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent, and fumed silica at a mass ratio of 40:10:1; stir at 3000 rpm for 15 min using a high-speed disperser; then spray the coating onto the substrate surface, controlling the wet film thickness to 80 μm; finally, perform step curing: 80℃ / 30 min to 120℃ / 60 min;

[0064] B2. Antistatic layer coating: Polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water were then weighed according to a mass ratio of 15:5:3:77; ultrasonically dispersed at 500W for 30min; then rolled onto the upper surface of the substrate layer, controlling the wet film thickness to 50μm; finally dried with hot air at 60℃ for 20min.

[0065] B3. Surface sealing coating construction: Finally, mix castor oil polyester polyol with OH value of 110mgKOH / g, hexamethylene diisocyanate trimer, and nano alumina at a mass ratio of 6:4:1; spray it onto the upper surface of the substrate layer under high pressure and control the wet film thickness to 100μm; finally, perform two-stage curing from 25℃ / 24h to 80℃ / 2h.

[0066] It should also be noted that the coating layer preparation process includes the following steps:

[0067] C1. Functional Coating Process: A 50 μm PBAT film was placed in a plasma chamber and treated at 300 W and 20 Pa for 120 s; subsequently, EDOT monomer was vapor-deposited and simultaneously atomized into a PSS solution; FeCl3 vapor catalyst was introduced, and the reaction was carried out at 60 °C for 30 min, forming a sheet resistance ≤10 on the substrate after functional coating. 6 Ω / sq of PEDOT:PSS layer;

[0068] C2. Preparation of peelable protective film: Coat the surface of a 25μm PHB film with an acrylic-itaconic ester adhesive with a Tg of -45℃; control the adhesive layer thickness to 10μm; and then cure at 80℃ for 48h.

[0069] C3. Coating layer lamination: Finally, with the functional coated conductive layer facing down, it is laminated with the functional coating using a 100℃ hot roller press at a speed of 0.3MPa and 1m / min; then the protective film adhesive side is bonded to the PBAT substrate side and rolled at room temperature.

[0070] Example 1: In this example, the preparation process of the biodegradable and environmentally friendly fiber tabletop, specifically, the key parameters for each step are as follows:

[0071] Step 1: Substrate layer fabrication:

[0072] A1. Moisture-proof sealing layer: Polylactic acid + 5wt% maleic anhydride + 5wt% nano montmorillonite → twin-screw extrusion (175℃) → casting film (thickness 0.3mm);

[0073] A2. Load-bearing reinforcement layer: Alkali treatment of flax fibers (5wt% NaOH, 60min) → KH550 coupling → Unidirectional layup (fiber volume fraction 55%) → Impregnation with epoxy soybean oil acrylate resin (containing 0.5wt% TPO) → UV pre-curing (365nm, 300mW / cm²) 2 );

[0074] A3. Core Layer: Recycled kraft paper honeycomb core impregnated with 40% PBS adhesive solution → dried at 80℃ → coated with PEI crosslinking agent (1.5g / m²). 2 );

[0075] A4. Outer reinforcing layer: acetylated hemp fiber cloth (8% weight gain) → hot-pressed composite PBF resin film (150℃);

[0076] A5. Lamination: Four layers stacked → hot pressing (160℃, 0.8MPa, 20min) → cooling and demolding;

[0077] Step 2: Applying the functional coating:

[0078] B1. Substrate surface treatment layer: Cashew phenol epoxy resin: polysaccharide anhydride: fumed silica = 40:10:1 → spraying (wet film 80μm) → step curing (80℃ / 30min → 120℃ / 60min);

[0079] B2. Antistatic layer: PVP: ionic liquid: nanocellulose: water = 15:5:3:77 → ultrasonic dispersion → roller coating (wet film 50μm) → drying at 60℃ for 20min;

[0080] B3. Surface sealing layer: castor oil polyester: HDI trimer: nano alumina = 6:4:1 → spraying (wet film 100μm) → two-stage curing (25℃ / 24h → 80℃ / 2h);

[0081] Step 3: Coating layer lamination:

[0082] C1. Functional Coating: PBAT thin film plasma activation (300W, 20Pa, 120s) → vapor deposition PEDOT: PSS (sheet resistance ≤10) 6 Ω / sq);

[0083] C2. Protective film: PHB film coated with acrylic adhesive (10μm) → cured at 80℃ for 48h;

[0084] C3. Lamination: Hot roll pressing (100℃, 0.3MPa) to bond the film layer;

[0085] Example 2: In this example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 1, and other processes and parameters were the same as in Example 1;

[0086] Example 3: In this example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 1, and other processes and parameters were the same as in Example 1;

[0087] Example 4: In this example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 1, and other processes and parameters were the same as in Example 1;

[0088] Example 5: In this example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 1, and other processes and parameters were the same as in Example 1;

[0089] The material composition variables for the examples are shown in Table 1:

[0090] Table 1: Parameter Table of Material Composition Variables in Examples

[0091] Group Moisture barrier nanoclay content Antistatic ionomer content Substrate layer hot press temperature Example 1 5 wt% 5 wt% 160℃ Example 2 3 wt% 5 wt% 160℃ Example 3 8 wt% 5 wt% 160℃ Example 4 5 wt% 3 wt% 160℃ Example 5 5 wt% 4 wt% 140℃

[0092] Comparative Example 1: In this comparative example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 2, with other processes and parameters the same as in Example 1;

[0093] Comparative Example 2: In this comparative example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 2. Other processes and parameters were the same as in Example 1.

[0094] Comparative Example 3: In this comparative example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 2, and other processes and parameters were the same as in Example 1.

[0095] Comparative Example 4: In this comparative example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 2, with other processes and parameters the same as in Example 1;

[0096] Comparative Example 5: In this comparative example, a biodegradable and environmentally friendly fiber tabletop was prepared according to the variable parameters in Table 2, with other processes and parameters the same as in Example 1;

[0097] The comparative material composition variables are shown in Table 2:

[0098] Table 2: Comparative Example Material Component Variable Parameter Table

[0099]

[0100]

[0101] III. Performance Testing:

[0102] Biodegradable and environmentally friendly fiber tabletop samples were prepared according to the parameters of Examples 1-5 and Comparative Examples 1-5, and the following performance tests were performed on each group of samples, and the performance data were recorded:

[0103] a. Moisture resistance: Water absorption rate after immersion in water for 48 hours (ASTM D570);

[0104] b. Mechanical properties: three-point bending strength (ISO178), interlaminar shear strength (ASTMD2344);

[0105] c. Antistatic properties: Surface resistivity (GB / T1410);

[0106] d. Degradation rate: Weight loss rate of soil after 90 days of burial (ISO 20200);

[0107] Performance data from the recorded examples are shown in Table 3:

[0108] Table 3: Comparison of Performance Data of Examples

[0109]

[0110]

[0111] The comparative performance data is recorded in Table 4:

[0112] Table 4: Comparison of Performance Data for Comparative Scales

[0113]

[0114] IV. Results and Discussion

[0115] Please refer to Tables 1 to 4. It can be seen that the moisture barrier layer of the example has a nano-montmorillonite content of 3-8 wt%, which is too low compared to the comparative example of 1,2 wt%, resulting in a 63% increase in water absorption. The comparative example of 2,10 wt%, is too high, which causes agglomeration and a 16% decrease in mechanical strength. The 5 wt% content in Example 1 balances the moisture barrier properties and mechanical properties.

[0116] Please refer to Tables 1 to 4. It can be seen that the ionic liquid in the antistatic layer of the examples, at 3–5 wt%, is too low compared to the 3.2 wt% in the comparative examples, resulting in a surface resistivity >10. 12 Ω, loss of antistatic properties; in the comparative example, an excessively high concentration of 4.6 wt% triggered ion precipitation, resulting in a 11.5% decrease in degradation rate;

[0117] Please refer to Tables 1 to 4. It can be seen that, compared to Example 5 (140°C), the lower hot-pressing temperature of 140–180°C in the comparative example resulted in insufficient resin curing, leading to a 15% decrease in flexural strength. In the comparative example 5, the higher temperature of 200°C caused thermal degradation of the substrate, resulting in a 50% decrease in interlaminar shear strength.

[0118] Furthermore, Example 1 optimizes dispersibility and barrier properties with 5wt% nano-montmorillonite, ensures antistatic properties with 5wt% ionic liquid, and achieves complete curing at 160℃ without heat damage through hot pressing. It has the lowest water absorption, the highest flexural strength, meets the surface resistance standard, and has a degradation rate of >75%, thus avoiding extreme risks of agglomeration and precipitation, making it suitable for industrial scale-up.

[0119] In summary, Embodiment 1 of this invention achieves the optimal solution within the component range due to the balance between components and processes, providing a reliable solution for the industrialization of biodegradable tabletops. This is the best embodiment of the invention. The fiber tabletop of this invention solves the solid waste problem caused by the non-degradability of petroleum-based composite materials when replacing traditional fiber tabletops with fully bio-based materials. It innovates an ion-conductive antistatic mechanism, overcomes the equipment interference and insufficient wear resistance caused by traditional metal fillers, and eliminates the use of toxic solvents through a low-temperature molding process, achieving zero pollution in the manufacturing process. This provides a sustainable solution for precision laboratories and green healthcare.

[0120] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0121] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A biodegradable and environmentally friendly fiber tabletop, characterized in that, include: The substrate layer is provided with a moisture-proof sealing layer, a load-bearing reinforcement layer, a core layer and an outer reinforcement layer from bottom to top. The moisture-proof sealing layer is a modified polylactic acid film composed of a polylactic acid matrix with a thickness ≥0.3mm, 5-8wt% of grafted modified maleic anhydride compatibilizer, and 3-5wt% nano-montmorillonite with a particle size <50nm; the load-bearing reinforcement layer is a unidirectional flax fiber and a bio-based resin pre-impregnated material; the core layer is a honeycomb core material; and the outer reinforcement layer is a plain-weave hemp fiber and a bio-based resin pre-impregnated material. A functional coating is applied to the top of the substrate layer, and the functional coating is provided with a substrate surface treatment layer, an antistatic layer and a surface sealing coating from bottom to top. The substrate surface treatment layer is a bio-based epoxy primer composed of cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent, and fumed silica. The mass ratio of cashew phenol glycidyl ether epoxy resin: polysaccharide anhydride curing agent: fumed silica is 40:10:1, and the fumed silica has a particle size of 12 nm. The antistatic layer is an ion-conductive waterborne coating composed of polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water. The mass ratio of imidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water is 15:5:3:77, and the diameter of the nanocellulose whiskers is 5-20 nm. The surface sealing coating is a bio-based polyurethane topcoat composed of castor oil-based polyester polyol, hexamethylene diisocyanate trimer, and nano-alumina, with a mass ratio of castor oil-based polyester polyol, hexamethylene diisocyanate trimer, and nano-alumina of 6:4:

1. The OH value of the castor oil-based polyester polyol is 110 mg KOH / g, and the nano-alumina has a particle size of 50 nm. A coating layer is bonded to the top of a functional coating layer, and the coating layer is provided with a functional coating and a peelable protective film from bottom to top. The functional coating substrate is polybutylene adipate / terephthalate, and its surface is grafted with a poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate conductive layer via plasma activation, with a sheet resistance ≤10. 6 Ω / sq, thickness 50μm; the peelable protective film is a polyhydroxybutyrate film with a thickness of 25μm.

2. The biodegradable and environmentally friendly fiber tabletop according to claim 1, characterized in that, In the pre-impregnated material of unidirectional flax fiber and bio-based resin in the load-bearing reinforcement layer, the unidirectional flax fiber is a unidirectional layup of long flax fiber bundles with a fiber volume fraction ≥55% that has been treated with alkali and silane coupling agent KH550. The bio-based resin is an epoxy soybean oil acrylate photocurable resin, which contains 0.5 wt% phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide photoinitiator.

3. The biodegradable and environmentally friendly fiber tabletop according to claim 2, characterized in that, The honeycomb core material of the external reinforcement is a polybutylene succinate resin solution with a solid content of 40% impregnated with 100% recycled kraft paper as raw material and a density ≥80kg / m³. 3 With a coating amount of 1.5 g / m 2 Surface treatment with polyethyleneimine crosslinking agent.

4. The biodegradable and environmentally friendly fiber tabletop according to claim 3, characterized in that, The outer reinforcing layer is composed of plain-weave hemp fiber and bio-based resin pre-impregnated material, with a basis weight of 200 g / m² after acetylation treatment. 2 Plain-weave hemp fiber fabric prepreg material with thermoplastic resin of furanyl dicarboxylate copolymer.

5. A method for preparing a biodegradable and environmentally friendly fiber tabletop according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Prepare a moisture-proof sealing layer, a load-bearing reinforcement layer, a core layer and an outer reinforcement layer, and stack the four layers in sequence and hot press them to form a substrate layer; S2. After cleaning the substrate layer obtained in S1, spray a mixture of cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent and fumed silica to cure and form a substrate surface treatment layer. Then roll-coat a mixture of polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers and deionized water to form an antistatic layer. Spray a mixture of castor oil-based polyester polyol, hexamethylene diisocyanate trimer and nanoalumina to cure and form a surface sealing coating. S3. A functional coating and a peelable protective film are sequentially laminated onto the substrate layer after the S2 coating is completed to form a coating layer. After roll pressing, a biodegradable and environmentally friendly fiber tabletop is obtained.

6. The biodegradable and environmentally friendly fiber tabletop according to claim 5, characterized in that, The substrate layer fabrication process includes the following steps: A1. Moisture-proof sealing layer forming: Polylactic acid granules are premixed with 5-8wt% maleic anhydride graft compatibilizer and 3-5wt% nano-montmorillonite with a particle size <50nm; then the mixture is fed into a twin-screw extruder for melt blending, and the extrusion temperature is controlled at 170-180℃; the melt is then cast through a T-die to a 40℃ mirror roller to form a film, and finally a film with a thickness ≥0.3mm is produced and wound up for later use; A2. Preparation of prepreg for load-bearing reinforcement layer: Long flax fiber bundles were immersed in 5wt% NaOH solution for 60 min, washed with water and then transferred to 1wt% KH550 silane coupling agent ethanol solution for impregnation. The fibers were then dried in an oven at 110℃; subsequently, the fiber bundles were laid up unidirectionally at a volume fraction ≥55% and impregnated in an epoxy soybean oil acrylate resin bath at 50℃, the resin containing 0.5wt% TPO photoinitiator; finally, the fibers were subjected to a 365nm wavelength, 300mW / cm² light treatment. 2 Pre-curing with high-intensity ultraviolet light to produce semi-cured sheets; A3. Core Layer Treatment: Hexagonal honeycomb core material is made from 100% recycled kraft paper, with each unit having a side length of 6mm; it is immersed in 40% PBS resin solution for 120s; then the solution is drained and dried in an 80℃ hot air oven for 30min; finally, PEI crosslinking agent is roller-coated, with the coating amount controlled at 1.5g / m². 2 ; A4. Preparation of outer reinforcement layer prepreg: 200g / m 2 Plain hemp fibers are arranged in an acetylation environment with acetic anhydride vapor to control the weight gain rate at 8-10%; then the fiber cloth is fed into a two-roller thermal laminator and double-sided laminated with MFI=15g / 10min PBF resin film at a roller temperature of 150℃. A5. Substrate lamination molding: The substrate is laminated in the following order: moisture-proof sealing layer, load-bearing reinforcement layer prepreg, core layer, and outer reinforcement layer prepreg; then it is fed into a hot press and pressed at 160℃ and 0.8MPa for 20 minutes; finally, it is cooled to 60℃ and demolded.

7. The biodegradable and environmentally friendly fiber tabletop according to claim 6, characterized in that, The functional coating preparation process includes the following steps: B1. Substrate surface treatment layer coating: Weigh cashew phenol glycidyl ether epoxy resin, polysaccharide anhydride curing agent, and fumed silica at a mass ratio of 40:10:1; stir at 3000 rpm for 15 min using a high-speed disperser; then spray the coating onto the substrate surface, controlling the wet film thickness to 80 μm; finally, perform step curing: 80℃ / 30 min to 120℃ / 60 min; B2. Antistatic layer coating: Polyvinylpyrrolidone, ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt, nanocellulose whiskers, and deionized water were then weighed according to a mass ratio of 15:5:3:77; ultrasonically dispersed at 500W for 30min; then rolled onto the upper surface of the substrate layer, controlling the wet film thickness to 50μm; finally dried with hot air at 60℃ for 20min. B3. Surface sealing coating construction: Finally, mix castor oil polyester polyol with OH value of 110mgKOH / g, hexamethylene diisocyanate trimer, and nano alumina at a mass ratio of 6:4:1; spray it onto the upper surface of the substrate layer under high pressure and control the wet film thickness to 100μm; finally, perform two-stage curing from 25℃ / 24h to 80℃ / 2h.

8. A biodegradable and environmentally friendly fiber tabletop according to claim 7, characterized in that, The preparation process of the coating layer includes the following steps: C1. Functional Coating Process: A 50 μm PBAT film was placed in a plasma chamber and treated at 300 W and 20 Pa for 120 s; subsequently, EDOT monomer was vapor-deposited and simultaneously atomized into a PSS solution; FeCl3 vapor catalyst was introduced, and the reaction was carried out at 60 °C for 30 min, forming a sheet resistance ≤10 on the substrate after functional coating. 6 Ω / sq of PEDOT:PSS layer; C2. Preparation of peelable protective film: Coat the surface of a 25μm PHB film with an acrylic-itaconic ester adhesive with a Tg of -45℃; control the adhesive layer thickness to 10μm; and then cure at 80℃ for 48h. C3. Coating layer lamination: Finally, with the functional coated conductive layer facing down, it is laminated with the functional coating using a 100℃ hot roller press at a speed of 0.3MPa and 1m / min; then the protective film adhesive side is bonded to the PBAT substrate side and rolled at room temperature.

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