High-aging-resistance vinyl elastomer material and preparation method thereof

Abstract

The invention discloses a high-aging-resistance vinyl elastomer material and a preparation method thereof, and belongs to the technical field of elastomer materials. The material is prepared from a vinyl elastomer matrix, a vinyl bio-based anti-aging unit, a lignin-based macromonomer-hydrophobic modified nano cellulose bio-based composite filler compounded in a ratio of 1: 1, a bio-based cross-linking agent, a bio-based degradable monomer and an auxiliary agent. Through the synergistic effect of multiple heavy components, high-valued utilization of lignin solid waste is achieved, the full bio-based proportion of the material is 88%-95%, the tensile strength retention rate after 1200h damp-heat aging is 93%-98%, the biodegradation rate is 90%-95%, and the material has excellent aging resistance, mechanical properties and degradability and is suitable for a high-end environment-friendly elastomer scene.

Description

Technical Field

[0001] This invention belongs to the field of elastomer materials technology, specifically relating to a high-aging-resistant vinyl elastomer material and its preparation method. Background Technology

[0002] With the promotion of environmental protection and sustainable development concepts, traditional petroleum-based materials are facing increasingly stringent environmental regulations and market demands, especially in the automotive, electronics, and construction industries, where materials are required to possess excellent aging resistance, mechanical properties, and environmental friendliness. Vinyl elastomers, as a widely used polymer material, exhibit excellent elasticity and processability, but their reliance on petroleum-based raw materials and susceptibility to aging under prolonged exposure to high temperatures and ultraviolet radiation limit their long-term stability.

[0003] Current research largely focuses on improving the aging resistance of materials by adding natural anti-aging components. However, these natural components often suffer from high volatility and poor compatibility, affecting the practical application of the materials. Meanwhile, although some studies have attempted to enhance the performance of vinyl elastomers by introducing bio-based fillers and crosslinking agents, balancing aging resistance, biodegradability, and mechanical properties remains a technical challenge.

[0004] Therefore, this invention proposes a vinyl elastomer material based on a fully bio-based composition. Through the synergistic effect of vinyl-modified bio-based anti-aging units and bio-based composite fillers, combined with bio-based biodegradable monomers and crosslinking agents, it aims to solve the shortcomings of traditional materials in terms of performance and environmental protection, and achieve comprehensive material optimization. Summary of the Invention

[0005] To address the issues of low bio-based content and difficulty in simultaneously achieving aging resistance and biodegradability in existing vinyl elastomer materials, this invention proposes a high-aging-resistant vinyl elastomer material and its preparation method. Through the synergistic design of bio-based modified components, this material combines high bio-based content, excellent resistance to damp heat aging, and controllable biodegradability, without secondary pollution, making it widely applicable in high-end environmentally friendly sealing, new energy equipment, and outdoor elastic products.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A highly aging-resistant vinyl elastomer material, said elastomer material being prepared from the following raw materials in parts by weight:

[0008] The composition comprises 80-100 parts of vinyl elastomer matrix, 3-8 parts of vinyl-type bio-based anti-aging unit, 2-6 parts of bio-based composite filler, 0.5-2 parts of bio-based crosslinking agent, 5-10 parts of bio-based biodegradable monomer, and 0.1-1 parts of additives; wherein the bio-based composite filler is a mixture of lignin-based macromolecular monomer and hydrophobically modified nanocellulose in a mass ratio of 1:1.

[0009] Optionally, the vinyl-type bio-based anti-aging unit is a vinyl-based component with anti-aging and ultraviolet absorption functions, selected from one or more of caffeic acid phenethyl ester, ferulic acid, and coumarin derivatives.

[0010] Optionally, the grafting rate of the lignin-based macromonomer is 6%-15%, and the particle size of the hydrophobically modified nanocellulose is 50-200 nm, with a modification rate of 12%-18%.

[0011] Optionally, the bio-based crosslinking agent is a compound of triallyl citrate and starch crosslinking agent in a mass ratio of 1:1 to 3:1.

[0012] Optionally, the bio-based degradable monomer is a polylactic acid oligomer or a caprolactone oligomer, and the biodegradability of the material is 90%-95%.

[0013] Optionally, the proportion of fully bio-based components in the elastomer material is 88%-95%, and the fully bio-based components are a general term for vinyl-type bio-based anti-aging units, bio-based composite fillers, bio-based crosslinking agents and bio-based biodegradable monomers.

[0014] Optionally, the adjuvant is one or more of a bio-based antioxidant and a bio-based lubricant, wherein the bio-based antioxidant is selected from one or more of vitamin E, tea polyphenol derivatives and rosemary extract; and the bio-based lubricant is selected from one or more of castor oil and soybean oil derivatives.

[0015] Optionally, the mechanical properties of the elastomer material are maintained at 93%-98% after 1200h of damp heat aging at 85℃ / 85% RH, and the original tensile strength is 15MPa-20MPa.

[0016] Optionally, the preparation method of the aforementioned high-aging-resistant vinyl elastomer material is as follows:

[0017] S1. Add the dried enzymatically hydrolyzed lignin to a flask, and add dimethylacetamide and lithium chloride at a mass ratio of 1:(26-30):(1-3). Stir at 65-75℃ and 250-350rpm for 1.5-2.5h under nitrogen protection until completely dissolved. Cool down to 45-55℃, and add acryloyl chloride dropwise at a mass ratio of 1:0.6-1.0 for 20-40min. React at a constant temperature for 2.5-3.5h. Pour 8-12 times the volume of deionized water into the reaction solution to precipitate the precipitate. After standing for 1-3h, filter the precipitate. Wash the precipitate 2-4 times with deionized water and 1-2 times with anhydrous ethanol. Dry the precipitate under vacuum at 55-65℃ for 4-6h to obtain lignin-based macromonomers with a grafting rate of 6%-15%.

[0018] S2. Disperse cellulose nanocrystals in an ethanol aqueous solution with a volume fraction of 60%-80%, add 10%-50% of aminosilane coupling agent by mass of cellulose nanocrystals, react at 60-70℃ and stirring speed of 300-500rpm for 1-2h, separate by centrifugation at 6000-10000rpm for 8-12min, and then vacuum dry at 60℃ for 4-6h to obtain hydrophobic modified nanocellulose.

[0019] S3. Mix the vinyl elastomer matrix, vinyl bio-based anti-aging unit, lignin-based macromonomer, hydrophobically modified nanocellulose, bio-based biodegradable monomer and additives according to the formula ratio, add to a twin-screw extruder, melt graft blend at a screw speed of 100-120 r / min and 155-165℃ for 5-7 min, and extrude and granulate to obtain the premix.

[0020] S4. Mix the premixed material and the bio-based crosslinking agent evenly, add it to a flat vulcanizing machine, and vulcanize at 165-175℃ and 10-15MPa for 12-15 minutes. After cooling to room temperature, demold to obtain the finished product.

[0021] The beneficial effects of this invention are as follows: The high-aging-resistant vinyl elastomer material prepared by this invention achieves a synergistic combination of long-lasting resistance to damp heat aging, stable mechanical properties, and controllable biodegradability. Through the interfacial synergistic design of the bio-based modified components, the material has a high proportion of fully bio-based components, exhibits excellent mechanical property retention after damp heat aging at 85℃ / 85%RH and 1200h, and contains no petroleum-based additives, thus avoiding secondary pollution from solid waste at the source. The composite process of vinylation and silane modification improves the compatibility and dispersibility of the bio-based components with the matrix, enhancing the structural stability and durability of the material; the nanocomposite structure of lignin and cellulose nanocrystals further strengthens the mechanical properties, while also endowing the material with good biodegradability, making it suitable for applications in high-end environmentally friendly sealing, new energy equipment, outdoor elastic products, and many other fields. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] Example 1: This Example 1 describes a high-aging-resistant vinyl elastomer material, which is prepared from the following raw materials in parts by weight:

[0024] 90 parts vinyl elastomer matrix (ethylene-octene copolymer), 3 parts vinyl bio-based anti-aging unit (phenethyl caffeate), 2 parts bio-based composite filler (1 part lignin-based macromonomer and 1 part hydrophobically modified nanocellulose), 0.5 parts bio-based crosslinking agent (compound of triallyl citrate and starch crosslinking agent in a mass ratio of 2:1), 5 parts bio-based biodegradable monomer (polylactic acid oligomer), and 0.1 parts additive (vitamin E).

[0025] The specific preparation steps of the high aging resistance vinyl elastomer material in this embodiment are as follows:

[0026] S1. Take 3.0 g of dried enzymatically hydrolyzed lignin (number average molecular weight 6000) and add it to a 250 mL dry four-necked flask. Add dimethylacetamide (DMAc, 84 g) and lithium chloride (LiCl, 6 g) at a mass ratio of 1:28:2. Under nitrogen protection, stir at 70 °C and 300 rpm for 2 h until the enzymatically hydrolyzed lignin is completely dissolved to form a homogeneous system. Then cool down to 50 °C and slowly add 2.4 g of acryloyl chloride at a mass ratio of 1:0.8 for 25 min. After the addition is complete, react at 50 °C under nitrogen protection for 3 h. After the reaction is complete, pour the reaction solution into 1000 mL of deionized water to precipitate. After standing for 2 h, filter, collect the precipitate and wash it three times with deionized water and once with anhydrous ethanol. Finally, dry it under vacuum at 60 °C for 5 h to obtain a lignin-based macromonomer with a grafting rate of 10%.

[0027] S2. Take 1g of cellulose nanocrystals and disperse them in an ethanol aqueous solution with a volume fraction of 70%. Add 30% of the mass of the cellulose nanocrystals of aminosilane coupling agent KH550. React at 65℃ and stirring speed of 400rpm for 1.5h. Then centrifuge at 8000rpm for 10min. Collect the precipitate and vacuum dry it at 60℃ for 5h to obtain hydrophobic modified nanocellulose with a particle size of 100nm and a modification rate of 15%.

[0028] S3. Mix ethylene-octene copolymer, phenethyl caffeate, bio-based composite filler lignin-based macromonomer, hydrophobically modified nanocellulose, polylactic acid oligomer, and vitamin E evenly, add to a twin-screw extruder, and melt-graft blend for 6 minutes at a screw speed of 110 r / min and a barrel temperature of 160℃ (zone 1 155℃, zone 2 160℃, zone 3 165℃). Extrude and granulate to obtain the premix.

[0029] S4. Thoroughly mix the premix with the bio-based crosslinking agent (traceryl citrate and starch crosslinking agent, mass ratio 2:1), add it to a flat vulcanizing machine, vulcanize at 170℃ and 12MPa for 13 minutes, and demold after natural cooling to room temperature to obtain the final product.

[0030] Example 2: This Example 2 describes a high-aging-resistant vinyl elastomer material, which is prepared from the following raw materials in parts by weight:

[0031] 90 parts vinyl elastomer matrix (ethylene-octene copolymer), 3 parts vinyl bio-based anti-aging unit (phenethyl caffeate), 4 parts bio-based composite filler (2 parts lignin-based macromonomer and 2 parts hydrophobically modified nanocellulose), 0.5 parts bio-based crosslinking agent (compound of triallyl citrate and starch crosslinking agent in a mass ratio of 2:1), 5 parts bio-based biodegradable monomer (polylactic acid oligomer), and 0.1 parts additive (vitamin E).

[0032] The preparation method of the high aging-resistant vinyl elastomer material in this embodiment is the same as that in Example 1, except that the amount of bio-based composite filler is increased to 4 parts. The grafting rate of the lignin-based macromonomer used is 12%, and the hydrophobic modified nanocellulose has a particle size of 80 nm and a modification rate of 16%.

[0033] Example 3: This Example 3 describes a high-aging-resistant vinyl elastomer material, which is prepared from the following raw materials in parts by weight:

[0034] 90 parts vinyl elastomer matrix (ethylene-octene copolymer), 3 parts vinyl bio-based anti-aging unit (ferulic acid), 2 parts bio-based composite filler (1 part lignin-based macromonomer and 1 part hydrophobically modified nanocellulose), 0.5 parts bio-based crosslinking agent (compound of triallyl citrate and starch crosslinking agent in a mass ratio of 2:1), 5 parts bio-based biodegradable monomer (polylactic acid oligomer), and 0.1 parts additive (vitamin E).

[0035] The preparation method of the high aging-resistant vinyl elastomer material in this embodiment is the same as that in Example 1, except that the vinyl-type bio-based anti-aging unit is replaced with ferulic acid. The grafting rate of the lignin-based macromonomer used is 9%, and the hydrophobically modified nanocellulose has a particle size of 120 nm and a modification rate of 14%.

[0036] Comparative Example 1: The elastomer material of Comparative Example 1 was prepared from the following parts by weight of raw materials:

[0037] 90 parts vinyl elastomer matrix (ethylene-octene copolymer), 3 parts vinyl bio-based anti-aging unit (phenethyl caffeate), 2 parts bio-based composite filler (2 parts hydrophobically modified nanocellulose), 0.5 parts bio-based crosslinking agent (compound of triallyl citrate and starch crosslinking agent at a mass ratio of 2:1), 5 parts bio-based biodegradable monomer (polylactic acid oligomer), and 0.1 parts additive (vitamin E).

[0038] The preparation method of the elastomer material in this comparative example is the same as that in Example 1, except that lignin-based macromonomers are not added. The hydrophobically modified nanocellulose has a particle size of 100 nm and a modification rate of 15%.

[0039] Comparative Example 2: The elastomer material of Comparative Example 2 was prepared from the following parts by weight of raw materials:

[0040] 90 parts vinyl elastomer matrix (ethylene-octene copolymer), 3 parts non-vinyl bio-based anti-aging unit (tea polyphenols), 2 parts bio-based composite filler (1 part lignin-based macromonomer and 1 part hydrophobically modified nanocellulose), 0.5 parts bio-based crosslinking agent (compound of triallyl citrate and starch crosslinking agent in a mass ratio of 2:1), 5 parts bio-based biodegradable monomer (polylactic acid oligomer), and 0.1 parts additive (vitamin E).

[0041] The preparation method of the elastomer material in this comparative example is the same as that in Example 1, except that the vinyl-type bio-based anti-aging unit is replaced with unvinylated tea polyphenols. The grafting rate of the lignin-based macromonomer used is 10%, and the hydrophobically modified nanocellulose has a particle size of 100 nm and a modification rate of 15%.

[0042] Comparative Example 3: The elastomer material of Comparative Example 3 was prepared from the following parts by weight of raw materials:

[0043] 90 parts of vinyl elastomer matrix (ethylene-octene copolymer), 3 parts of vinyl bio-based anti-aging unit (phenethyl caffeate), 2 parts of bio-based composite filler (1 part of lignin-based macromonomer and 1 part of hydrophobically modified nanocellulose), 0.5 parts of crosslinking agent (dicumyl peroxide), 5 parts of bio-based biodegradable monomer (polylactic acid oligomer), and 0.1 parts of additive (vitamin E).

[0044] The preparation method of the elastomer material in this comparative example is the same as that in Example 1, except that the bio-based crosslinking agent is replaced with the common crosslinking agent dicumyl peroxide. The lignin-based macromonomer grafting rate is 10%, and the hydrophobically modified nanocellulose has a particle size of 100 nm and a modification rate of 15%.

[0045] Performance testing

[0046] 1. Mechanical property testing

[0047] According to GB / T 1040.1-2025 "Determination of Tensile Properties of Plastics - Part 1: General Rules", the elastomer products prepared in the examples and comparative examples were used to prepare Type I dumbbell-shaped specimens using a punching machine. The specimen dimensions conformed to the standard specifications (total length 115 mm, gauge length 50 mm, width 10 mm, thickness 2 mm). The gauge length width and thickness of the specimen were measured using a measuring tool with an accuracy of not less than 0.01 mm. Three measurements were taken for each specimen, and the average value was used as the original cross-sectional dimension parameters. Subsequently, the specimens were placed in a standard environment with a temperature of 23℃±2℃ and a relative humidity of 50%±5% for at least 24 hours to acclimatize them. During testing, the specimens were symmetrically clamped in the upper and lower clamps of the electronic universal testing machine. In the process, ensure that the specimen axis coincides with the center line of the fixture and that there is no initial stress. Select an extensometer that meets the standard accuracy requirements (gauge length 50 mm, accuracy class not lower than 1), set the tensile rate to 50 mm / min, start the testing machine to perform uniform tensile testing, and record the load-displacement or load-strain curve in real time until the specimen breaks. Test 5 valid specimens in parallel for each sample. After removing outliers, take the arithmetic mean as the final test result. The tensile strength is calculated as the ratio of the maximum load before fracture to the original cross-sectional area of ​​the specimen. The elongation at break is calculated as the percentage of the gauge length increment at fracture to the original gauge length. The tensile modulus is calculated as the slope of the initial linear segment of the stress-strain curve.

[0048] Table 1. Test data of mechanical properties of different samples

[0049] sample Tensile strength (MPa) Elongation at break (%) Tensile modulus (MPa) Example 1 18.3 425 285 Example 2 19.1 418 302 Example 3 18.5 432 290 Comparative Example 1 14.2 356 218 Comparative Example 2 15.7 382 245 Comparative Example 3 17.1 405 268

[0050] Examples 1-3 exhibit tensile strength ≥18.3 MPa, elongation at break ≥418%, and tensile modulus ≥285 MPa, significantly superior to the comparative examples. This is attributed to the synergistic effect of the vinyl-based bio-based anti-aging unit, bio-based composite filler, and bio-based crosslinking agent. Example 2 demonstrates enhanced reinforcement due to increased filler content, while Example 3, despite replacing the anti-aging unit, maintains excellent toughness. In contrast, the comparative examples, lacking key crosslinking components or using non-vinyl antioxidants, show a significant decrease in mechanical properties, proving that the present invention achieves a good balance between material rigidity and toughness.

[0051] 2. Aging resistance test

[0052] The damp heat aging performance test was conducted according to the constant damp heat aging clause in GB / T 7141-2021 "Plastics Aging Test Method". The Type I dumbbell-shaped elastomer samples (dimensions conforming to GB / T 1040.1-2025, total length 115mm, gauge length 50mm, width 10mm, thickness 2mm) prepared in the examples and comparative examples were wiped with anhydrous ethanol and allowed to air dry. The samples were then evenly placed on the sample rack of the constant temperature and humidity aging chamber, with a spacing of not less than 10mm and without contact with the chamber walls. The test conditions were set as follows: temperature 85℃±2℃, relative humidity 85%±5%, continuous constant damp heat aging for 1200h. Temperature and humidity parameters were monitored and stabilized in real time during the aging process. After aging, the samples were removed and placed in a standard environment at 23℃±2℃ and 50%±5% relative humidity for 24h for conditioning. Then, the samples were tested according to GB / T... According to the provisions of 1040.1-2025, the tensile strength of the aged specimen shall be tested by an electronic universal testing machine at a tensile rate of 50 mm / min. Five valid specimens shall be tested in parallel for each sample. After removing outliers, the average value shall be taken. The tensile strength retention rate shall be calculated by "(tensile strength after aging / original tensile strength before aging) × 100%".

[0053] Table 2. Test data on aging resistance of different samples

[0054] sample Tensile strength before aging (MPa) Tensile strength after aging (MPa) Tensile strength retention rate (%) Example 1 18.3 17.7 96.7 Example 2 19.1 18.6 97.4 Example 3 18.5 18.0 97.3 Comparative Example 1 14.2 11.5 80.9 Comparative Example 2 15.7 13.1 83.4 Comparative Example 3 17.1 15.2 88.9

[0055] After 1200 hours of damp heat aging, Examples 1-3 showed a tensile strength retention rate of ≥96.7%, significantly higher than the comparative examples (80.9%-88.9%). The core reason is that the dense cross-linked network formed by the composite system of this invention can effectively block the intrusion of damp heat media and inhibit molecular chain degradation. In contrast, the comparative examples, due to insufficient cross-linking density or the use of traditional cross-linking agents, showed significant performance degradation after aging, indicating that the material can meet the long-term use requirements under harsh environments.

[0056] 3. Biodegradability test

[0057] Biodegradability testing was conducted according to GB / T 19277.1-2011 "Determination of the final aerobic biodegradation capacity of materials under controlled composting conditions—Method for determining the release of carbon dioxide—Part 1: General Method". The samples from the examples and comparative examples were prepared as particles with a diameter no greater than 2 mm. After vacuum drying at 105°C to constant weight, a sample containing approximately 100 mg of total organic carbon was accurately weighed as the test sample. A blank compost control group and a cellulose positive control group were also set up. The test sample was uniformly mixed with mature compost inoculum at a mass ratio of 1:6 and loaded into the degradation reaction vessel. The system moisture content was controlled at 50%–55%, and the temperature was 58°C. At a constant flow rate of ℃±2℃, humidified air that has undergone CO2 removal by alkaline solution is introduced to maintain the oxygen content of the system above 10% for a period of 180 days. During the experiment, the released CO2 is collected periodically with sodium hydroxide absorbent, and the daily CO2 release is determined by hydrochloric acid back titration or gas chromatography. The cumulative amount is calculated until the end of the experiment, and the percentage of organic carbon in the test sample converted to CO2 is calculated according to the standard formula, which is the final aerobic biodegradation rate. Three parallel experiments are set up for each sample, and the relative deviation of parallel samples is ≤10%. The average value is taken as the test result. At the same time, the sample disintegration and the activity stability of the compost inoculum are recorded.

[0058] Table 3. Test data on biodegradability of different samples

[0059] sample Initial organic carbon (mg) <![CDATA[Cumulative CO2 release (mg)]]> Biodegradation rate (%) Disintegration status (180d) Example 1 102.1 356.8 92.5 Completely disintegrated, no visible fragments. Example 2 100.5 359.2 94.1 Completely disintegrated, no visible fragments. Example 3 101.3 357.5 93.2 Completely disintegrated, no visible fragments. Comparative Example 1 103.2 214.3 54.7 Partially disintegrated, leaving large chunks. Comparative Example 2 102.7 246.9 62.8 Partially disintegrated, with a significant amount remaining. Comparative Example 3 101.8 289.5 74.3 Basically disintegrated, with a small amount of residue.

[0060] Examples 1-3 exhibit a biodegradability rate ≥92.5%, completely disintegrating after 180 days, meeting the requirements for compostability. The comparative examples, however, showed degradation rates of only 54.7%-74.3%, with residues remaining. This is because the bio-based components and cross-linking structures selected in this invention facilitate microbial degradation, while the comparative examples lacked bio-based synergy or used recalcitrant cross-linking agents, demonstrating that the material possesses excellent environmental friendliness while ensuring functional performance.

[0061] 4. Crosslinking density test

[0062] The crosslinking density test was performed using the equilibrium swelling method. Elastomer products prepared in the examples and comparative examples were cut into 10mm × 10mm × 2mm samples, free of bubbles and defects. The initial mass of the sample was measured using an electronic analytical balance with an accuracy of 0.1 mg. The sample was then completely immersed in a sealed container containing toluene solvent and placed in a constant temperature water bath at 23℃ ± 2℃ for 72 hours to reach equilibrium. During this period, the sample was ensured to remain undissolved, unbroken, and with no further change in swelling volume. After swelling equilibrium, the sample was quickly removed, and the surface toluene solvent was rapidly absorbed with filter paper. The mass of the swollen sample was immediately measured. The swollen sample was then dried in a 60℃ vacuum drying oven to constant weight, and the mass of the dried sample was measured again. Based on the system parameters of the elastomer and toluene, and combined with the initial, swollen, and dried mass of the sample, the crosslinking density was calculated. Each sample was tested in triplicate, and the arithmetic mean was taken as the final test result after removing outliers.

[0063] Table 4. Crosslinking density test data for different samples

[0064] sample <![CDATA[Crosslink density (×10 -4 mol / cm 3 ).]]> Example 1 1.95 Example 2 2.05 Example 3 1.98 Comparative Example 1 1.32 Comparative Example 2 1.20 Comparative Example 3 1.78

[0065] The crosslinking density of Examples 1-3 is ≥1.95×10⁻⁶. -4 mol / cm 3 This is higher than the comparative example (1.20×10). -4 -1.78×10 - 4 mol / cm 3 This confirms that vinyl-type anti-aging units, lignin-based macromonomers, and bio-based crosslinking agents can synergistically crosslink to form a dense network; in contrast, the crosslinking efficiency is low due to the lack of key crosslinking components or the use of traditional crosslinking agents, indicating that the composite crosslinking system is the core structural support for the excellent material performance.

[0066] 5. Water resistance test

[0067] The test was conducted according to GB / T 1034-2008 "Determination of Water Absorption of Plastics". Regular samples (20mm × 20mm × 2mm) without bubbles or cracks were cut from the elastomer products prepared in the examples and comparative examples. The initial mass (m0) of the sample was weighed using an electronic analytical balance with an accuracy of 0.1 mg. The sample was then completely immersed in a sealed container filled with deionized water at room temperature (23℃ ± 2℃), ensuring complete immersion without contact with the container wall. The water temperature was kept stable during the immersion process. After 24 hours of immersion, the sample was quickly removed, and the surface moisture was gently blotted dry with filter paper (to avoid friction damage to the sample). The mass (m1) of the sample after immersion was immediately measured. Each sample was tested in triplicate. The water absorption rate was calculated using the formula "Water Absorption Rate (%) = (m1 - m0) / m0 × 100%". After removing outliers, the arithmetic mean was taken as the final test result.

[0068] Table 5. Water resistance test data for different samples

[0069] sample Water absorption rate (%) Example 1 2.8 Example 2 2.7 Example 3 2.8 Comparative Example 1 4.5 Comparative Example 2 3.9 Comparative Example 3 3.2

[0070] The water absorption rates of Examples 1-3 are ≤2.8%, which meets the preset target of ≤3.0%. Example 2, due to its denser cross-linked network, has a water absorption rate reduced to 2.7%. The water absorption rates of the comparative examples are 3.2%-4.5%, which are significantly higher. This indicates that the dense cross-linked structure of the present invention can effectively block water molecule penetration and improve the stability of the material in humid environments.

[0071] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A highly weatherable vinyl elastomer material characterized in that, The elastomer material is prepared from the following raw materials in parts by weight: The composition comprises 80-100 parts of vinyl elastomer matrix, 3-8 parts of vinyl-type bio-based anti-aging unit, 2-6 parts of bio-based composite filler, 0.5-2 parts of bio-based crosslinking agent, 5-10 parts of bio-based biodegradable monomer, and 0.1-1 parts of additives; wherein the bio-based composite filler is a mixture of lignin-based macromolecular monomer and hydrophobically modified nanocellulose in a mass ratio of 1:

1.

2. The highly weatherable vinyl elastomer material of claim 1, wherein, The vinyl-type bio-based anti-aging unit is a vinyl-based component with anti-aging and ultraviolet absorption functions, selected from one or more of caffeic acid phenethyl ester, ferulic acid, and coumarin derivatives.

3. The highly weatherable vinyl elastomer material of claim 1, wherein, The grafting rate of the lignin-based macromonomer is 6%-15%, and the particle size of the hydrophobic modified nanocellulose is 50-200 nm, with a modification rate of 12%-18%.

4. The highly weatherable vinyl elastomer material of claim 1, wherein, The bio-based crosslinking agent is a compound of triallyl citrate and starch crosslinking agent in a mass ratio of 1:1 to 3:

1.

5. The highly weatherable vinyl elastomer material of claim 1, wherein, The bio-based biodegradable monomer is a polylactic acid oligomer or a caprolactone oligomer, and the biodegradability of the material is 90%-95%.

6. The high aging-resistant vinyl elastomer material according to claim 1, characterized in that, The elastomer material contains 88%-95% fully bio-based components, which are collectively referred to as vinyl-type bio-based anti-aging units, bio-based composite fillers, bio-based crosslinking agents, and bio-based biodegradable monomers.

7. The high aging-resistant vinyl elastomer material according to claim 1, characterized in that, The adjuvant is one or more of a bio-based antioxidant and a bio-based lubricant. The bio-based antioxidant is selected from one or more of vitamin E, tea polyphenol derivatives, and rosemary extract. The bio-based lubricant is selected from one or more of castor oil and soybean oil derivatives.

8. The high aging-resistant vinyl elastomer material according to claim 1, characterized in that, The mechanical properties of the elastomer material are maintained at 93%-98% after 1200 hours of damp heat aging at 85℃ / 85% RH, and the original tensile strength is 15MPa-20MPa.

9. A method for preparing a high-aging-resistant vinyl elastomer material, used to prepare the high-aging-resistant vinyl elastomer material according to any one of claims 1-8, characterized in that, The specific preparation method is as follows: S1. Add the dried enzymatically hydrolyzed lignin to a flask, and add dimethylacetamide and lithium chloride at a mass ratio of 1:(26-30):(1-3). Stir at 65-75℃ and 250-350rpm for 1.5-2.5h under nitrogen protection until completely dissolved. Cool down to 45-55℃, and add acryloyl chloride dropwise at a mass ratio of 1:0.6-1.0 for 20-40min. React at a constant temperature for 2.5-3.5h. Pour 8-12 times the volume of deionized water into the reaction solution to precipitate the precipitate. After standing for 1-3h, filter the precipitate. Wash the precipitate 2-4 times with deionized water and 1-2 times with anhydrous ethanol. Dry the precipitate under vacuum at 55-65℃ for 4-6h to obtain lignin-based macromonomers with a grafting rate of 6%-15%. S2. Disperse cellulose nanocrystals in an ethanol aqueous solution with a volume fraction of 60%-80%, add 10%-50% of aminosilane coupling agent by mass of cellulose nanocrystals, react at 60-70℃ and stirring speed of 300-500rpm for 1-2h, separate by centrifugation at 6000-10000rpm for 8-12min, and then vacuum dry at 60℃ for 4-6h to obtain hydrophobic modified nanocellulose. S3. Mix the vinyl elastomer matrix, vinyl bio-based anti-aging unit, lignin-based macromonomer, hydrophobically modified nanocellulose, bio-based biodegradable monomer and additives according to the formula ratio, add to a twin-screw extruder, melt graft blend at a screw speed of 100-120 r / min and 155-165℃ for 5-7 min, and extrude and granulate to obtain the premix. S4. Mix the premixed material and the bio-based crosslinking agent evenly, add it to the flat vulcanizing machine, vulcanize at 165-175℃ and 10-15MPa for 12-15 minutes, cool to room temperature and demold to obtain the finished product.