Ecological restoration composite material and preparation method thereof

Abstract

The invention relates to the technical field of ecological restoration, in particular to an ecological restoration composite material and a preparation method thereof. Comprising a base material: 30-70 parts of a natural polymer material or a degradable synthetic polymer material; reinforced fibers: 5-40 parts of natural fibers or degradable synthetic fibers; a functional additive: 10-40 parts of at least one of a water-retaining agent, an organic fertilizer, a microbial carrier and a soil conditioner; a plant growth promoter: 1-15 parts of humic acid, a seaweed extract, a trace element fertilizer or an antagonistic antibacterial agent; a binder: 0 to 15 parts of a degradable polymer binder; and 5-15 parts by weight of water. According to the invention, the biodegradability of the material is ensured, the mechanical strength is improved and the overall performance of the composite material is enhanced by optimizing the combination of base materials, pretreating the reinforced fibers, achieving the synergistic effect of the multifunctional additive and efficiently loading the plant growth promoter; the ecological restoration composite material provides long-term support for plant growth.

Description

Technical Field

[0001] The invention relates to the technical field of ecological restoration, in particular to an ecological restoration composite material and a preparation method thereof. Background Art

[0002] With the acceleration of industrialization and urbanization, the ecological environment has suffered serious damage, such as soil erosion, desertification, abandoned mines and other problems have become increasingly prominent. In order to deal with these problems, ecological restoration materials have emerged. They are usually composed of base materials, reinforcing fibers, functional additives, etc., which are used to improve soil structure, provide nutrients, retain moisture and promote plant growth. Although the existing technology has made some progress, there are still some shortcomings:

[0003] 1. Traditional natural polymer-based materials have low mechanical strength and are difficult to meet the needs of long-term use; while synthetic degradable polymer materials have higher strength, their degradation rate is slow and may cause long-term burden on the environment.

[0004] 2. The dispersion of the reinforcing fibers in the prior art is poor, and they are prone to agglomeration, which affects the overall performance of the composite material.

[0005] 3. Different types of additives (such as water retaining agents, organic fertilizers, etc.) are not compatible with each other and are prone to separation or failure during the mixing process.

[0006] 4. Existing plant growth promoters lack effective loading and sustained-release mechanisms and are easily released in a short period of time, failing to provide lasting support.

[0007] Therefore, in view of this, the existing technology was studied and improved, and an ecological restoration composite material and a preparation method thereof were proposed. Summary of the invention

[0008] The problems to be solved by the present invention are that the mechanical properties of the matrix material are insufficient, the reinforcing fibers are unevenly dispersed, the compatibility of the functional additives is poor, and the release control of the plant growth promoter is poor.

[0009] The technical solution adopted by the present invention is: an ecological restoration composite material, comprising the following components in parts by weight:

[0010] Matrix material: 30-70 parts by weight of natural polymer material or degradable synthetic polymer material;

[0011] Reinforcement fiber: 5-40 parts by weight of natural fiber or degradable synthetic fiber;

[0012] Functional additives: 10-40 parts by weight of at least one of a water retaining agent, an organic fertilizer, a microbial carrier, and a soil conditioner;

[0013] Plant growth promoter: 1-15 parts by weight of humic acid, seaweed extract, trace element fertilizer or antagonistic bacteria;

[0014] Binder: 0-15 parts by weight of a degradable polymer binder;

[0015] Water: 5-15 parts by weight, used for molding.

[0016] As a further solution of the present invention: the natural polymer material is selected from at least one of starch, chitosan, and lignin; the degradable synthetic polymer material is selected from at least one of polylactic acid (PLA), polyhydroxyalkanoate (PHA), and polybutylene adipate / terephthalate (PBAT).

[0017] As a further solution of the present invention: the reinforcing fiber is selected from at least one of bamboo fiber, hemp fiber, coconut shell fiber or polylactic acid fiber, and the fiber length is 1-5 cm.

[0018] As a further solution of the present invention: the water retaining agent is polyacrylate, bentonite or porous zeolite; the organic fertilizer is decomposed organic fertilizer or slow-release fertilizer; the microbial carrier is at least one of biochar and sodium alginate gel particles; the soil conditioner is diatomaceous earth, apatite or zeolite.

[0019] As a further embodiment of the present invention: the plant growth promoter further comprises at least one of gibberellins and indoleacetic acid, and the antagonistic bacteria is at least one of nitrogen-fixing bacteria and phosphate-solubilizing bacteria.

[0020] A method for preparing an ecological restoration composite material comprises the following steps:

[0021] S1. Pretreatment of base materials: crush the natural / degradable polymer materials to a particle size of ≤100 mesh, dry them and set them aside;

[0022] S2. Mixing reinforcing fibers and additives: mixing the base material with reinforcing fibers, water retaining agent, organic fertilizer and microbial carrier;

[0023] S3, melt blending: adding the molten degradable polymer binder, stirring at 100-200 rpm for 10-20 minutes at 160-180°C;

[0024] S4, functional treatment: dissolving the plant growth promoter and spraying it on the surface of the mixture;

[0025] S5. Molding and curing: Add appropriate amount of water to adjust the humidity, press and shape at a pressure of 5-10MPa, and cure at room temperature or 40-60℃ for 12-48 hours.

[0026] As a further solution of the present invention: in S1, a weak alkaline solution is used to clean the natural fiber, the drying temperature is 50-70° C., and the drying time is 2-4 hours.

[0027] As a further solution of the present invention: the loading amount of the plant growth promoter in S4 is 3-8% of the total weight of the composite material, and after spraying, it is ventilated and dried at 40-60° C. for 2-4 hours.

[0028] As a further solution of the present invention: in S5, ultraviolet radiation or a chemical crosslinking agent is used for crosslinking, and the crosslinking agent is citric acid or glutaraldehyde, the crosslinking temperature is 25-60° C., and the treatment time is 1-3 hours.

[0029] Beneficial effects of the present invention:

[0030] 1. Optimize the combination of matrix materials: The combination of natural polymer materials and degradable synthetic polymer materials not only ensures the biodegradability of the materials, but also improves the mechanical strength.

[0031] 2. Reinforced fiber pretreatment: Through weak alkaline solution cleaning and drying treatment, the dispersion uniformity of the fiber is improved and the overall performance of the composite material is enhanced.

[0032] 3. Synergistic effect of multifunctional additives: Select water-retaining agents, organic fertilizers, microbial carriers, etc. with good compatibility to ensure that the components do not separate during the mixing process and give full play to their respective functions.

[0033] 4. Efficient loading of plant growth promoters: Through spraying and cross-linking treatment, effective loading and slow release of plant growth promoters are achieved, providing long-term support for plant growth. DETAILED DESCRIPTION

[0034] The present invention will be further described below.

[0035] Example 1

[0036] Ecological restoration composite material composition:

[0037] Matrix material: 40 parts by weight of starch and 30 parts by weight of polylactic acid (PLA) are mixed.

[0038] Reinforcement fiber: 20 parts by weight of bamboo fiber, 2-3 cm in length.

[0039] Functional additives: 20 parts by weight of polyacrylate as a water retaining agent, and 10 parts by weight of decomposed organic fertilizer as an organic fertilizer.

[0040] Plant growth promoter: 5 parts by weight of seaweed extract.

[0041] Binder: 10 parts by weight of molten PLA.

[0042] Water: appropriate amount.

[0043] Preparation method:

[0044] S1. Grind starch and PLA to a particle size of ≤100 mesh and dry at 50°C for 4 hours.

[0045] S2. Wash the bamboo fiber with a weak alkaline solution and dry it at 50° C. for 2 hours.

[0046] S3, mixing the pretreated base material, bamboo fiber, polyacrylic acid salt and decomposed organic fertilizer evenly.

[0047] S4. Add molten PLA binder and stir at 170° C. and 150 rpm for 15 minutes.

[0048] S5. Dissolve the seaweed extract and spray it on the surface of the mixture. The loading amount is 5% of the total weight of the composite material. Dry it at 40° C. for 3 hours under ventilation.

[0049] S6. Add appropriate amount of water to adjust the humidity, press into shape under a pressure of 8MPa, and cure at room temperature for 24 hours.

[0050] Example 2

[0051] Ecological restoration composite material composition:

[0052] Matrix material: 50 parts by weight of chitosan and 20 parts by weight of polyhydroxyalkanoate (PHA).

[0053] Reinforcement fiber: 15 parts by weight of hemp fiber, 1-2 cm in length.

[0054] Functional additives: 15 parts by weight of bentonite as a water retaining agent, 15 parts by weight of slow-release fertilizer as an organic fertilizer, and 5 parts by weight of biochar as a microbial carrier.

[0055] Plant growth promoter: 3 parts by weight of humic acid mixed with 2 parts by weight of gibberellin.

[0056] Binder: 5 parts by weight of molten PHA.

[0057] Water: appropriate amount.

[0058] Preparation method:

[0059] S1. Grind chitosan and PHA to a particle size of ≤100 mesh and dry at 60°C for 3 hours.

[0060] S2. Wash the hemp fiber with a weak alkaline solution and dry it at 60° C. for 3 hours.

[0061] S3. Evenly mix the pretreated base material, hemp fiber, bentonite, slow-release fertilizer and biochar.

[0062] S4. Add molten PHA binder and stir at 160° C. and 200 rpm for 10 minutes.

[0063] S5. Dissolve humic acid and gibberellin and spray them on the surface of the mixture. The loading amount is 4% of the total weight of the composite material. Dry at 50° C. for 2 hours under ventilation.

[0064] S6. Add appropriate amount of water to adjust the humidity, press into shape at a pressure of 10 MPa, and cure at 40°C for 24 hours.

[0065] Example 3

[0066] Ecological restoration composite material composition:

[0067] Matrix material: 60 parts by weight of lignin and 10 parts by weight of polybutylene adipate / terephthalate (PBAT).

[0068] Reinforcement fiber: 30 parts by weight of coconut shell fiber, 3-5 cm in length.

[0069] Functional additives: 25 parts by weight of porous zeolite as a water retaining agent, and 10 parts by weight of diatomaceous earth as a soil conditioner.

[0070] Plant growth promoter: 8 parts by weight of trace element fertilizer and 2 parts by weight of phosphate-solubilizing bacteria are mixed.

[0071] Binder: None.

[0072] Water: appropriate amount.

[0073] Preparation method:

[0074] S1. Grind lignin and PBAT to a particle size of ≤100 mesh and dry at 70°C for 2 hours.

[0075] S2, washing the coconut shell fiber with a weak alkaline solution and drying it at 70° C. for 2 hours.

[0076] S3, mixing the pretreated base material, coconut shell fiber, porous zeolite and diatomaceous earth evenly.

[0077] S4. Since no adhesive is used in this example, proceed directly to the next step.

[0078] S5. Dissolve the trace element fertilizer and phosphate-solubilizing bacteria and spray them on the surface of the mixture, with the loading amount being 6% of the total weight of the composite material, and dry them at 60° C. for 4 hours under ventilation.

[0079] S6. Add appropriate amount of water to adjust humidity, press and shape at 7MPa pressure, and cure at 60℃ for 12 hours. Use citric acid as cross-linking agent, cross-linking temperature at 40℃, and treatment time for 2 hours.

[0080] Comparison of embodiments:

[0081] 1. Base material:

[0082] Example 1 uses a mixture of starch and polylactic acid (PLA) as the matrix material, focusing on biodegradability and a certain mechanical strength.

[0083] Example 2 uses chitosan and polyhydroxyalkanoate (PHA). These two materials also have good biodegradability, and chitosan has antibacterial properties and is suitable for specific ecological restoration needs.

[0084] In Example 3, lignin is combined with polybutylene adipate / terephthalate (PBAT) to improve the biodegradability of the composite material and reduce the cost.

[0085] 2. Reinforced fiber:

[0086] Bamboo fiber, hemp fiber and coconut shell fiber are used as reinforcing materials in Examples 1, 2 and 3, respectively. They provide different strength and toughness properties and are all derived from renewable resources.

[0087] 3. Functional additives:

[0088] Example 1 mainly adds water retaining agent and organic fertilizer, focusing on soil water retention and nutrient supply.

[0089] In Example 2, biochar was additionally added as a microbial carrier to enhance the support for microbial activity.

[0090] Example 3 uses porous zeolite and diatomaceous earth, which not only retains water but also improves soil structure.

[0091] 4. Plant growth promoter:

[0092] Different types of plant growth promoters are added in each embodiment, such as seaweed extract, a mixture of humic acid and gibberellin, and a mixture of trace element fertilizer and phosphate-solubilizing bacteria, in order to promote plant growth and improve soil fertility.

[0093] 5. Binder and curing:

[0094] In Example 1 and Example 2, molten PLA and PHA are used as binders to enhance the overall performance of the composite material.

[0095] Example 3 does not use a binder, but the stability and durability of the material are improved by citric acid cross-linking treatment.

[0096] 6. Preparation method and conditions:

[0097] The various embodiments differ in material pretreatment, mixing, spraying, compression molding and curing, but all follow the principle of ensuring uniform dispersion of materials, effective loading and slow release of plant growth promoters.

[0098] In summary, the present invention provides three different compositions of ecological restoration composite materials, each of which is optimized for specific ecological restoration needs. By adjusting the types and proportions of matrix materials, reinforcing fibers, functional additives and plant growth promoters, and adopting appropriate preparation methods and conditions, these composite materials show different advantages in biodegradability, mechanical strength, water retention, nutrient supply and soil improvement.

[0099] In practical applications, appropriate embodiments can be selected according to the specific needs of ecological restoration projects. For example, in areas where vegetation coverage needs to be quickly established and sufficient nutrients need to be provided, embodiment 1 can be selected; in projects that need to enhance soil microbial activity and improve soil structure, embodiment 2 may be more appropriate; and in cost-sensitive applications that require long-term soil improvement effects, embodiment 3 has greater potential.

[0100] In summary, the ecological restoration composite material of the present invention has broad application prospects and flexibility, can meet the needs of different ecological restoration projects, and provide strong support for ecological restoration and environmental protection.

[0101] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An ecological restoration composite material, characterized in that: The composition comprises the following components in parts by weight: Matrix material: 30-70 parts by weight of natural polymer material or degradable synthetic polymer material; Reinforcement fiber: 5-40 parts by weight of natural fiber or degradable synthetic fiber; Functional additives: 10-40 parts by weight of at least one of a water retaining agent, an organic fertilizer, a microbial carrier, and a soil conditioner; Plant growth promoters: 1-15 parts by weight of humic acid, seaweed extract, trace element fertilizer, or antagonistic bacteria; Binder: 0-15 parts by weight of a degradable polymer binder; Water: 5-15 parts by weight, used for molding.

2. The ecological restoration composite material according to claim 1, characterized in that: The natural polymer material is selected from at least one of starch, chitosan, and lignin; the degradable synthetic polymer material is selected from at least one of polylactic acid (PLA), polyhydroxyalkanoate (PHA), and polybutylene adipate / terephthalate (PBAT).

3. The ecological restoration composite material according to claim 1, characterized in that: The reinforcing fiber is selected from at least one of bamboo fiber, hemp fiber, coconut shell fiber or polylactic acid fiber, and the fiber length is 1-5 cm.

4. The ecological restoration composite material according to claim 1, characterized in that: The water retaining agent is polyacrylate, bentonite or porous zeolite; the organic fertilizer is decomposed organic fertilizer or slow-release fertilizer; the microbial carrier is at least one of biochar and sodium alginate gel particles; and the soil conditioner is diatomaceous earth, apatite or zeolite.

5. The ecological restoration composite material according to claim 1, characterized in that: The plant growth promoter further comprises at least one of gibberellins and indoleacetic acid, and the antagonist is at least one of nitrogen-fixing bacteria and phosphate-solubilizing bacteria.

6. A method for preparing an ecological restoration composite material, characterized in that: The following steps are involved: S1. Pretreatment of base materials: crush the natural / degradable polymer materials to a particle size of ≤100 mesh, dry them and set them aside; S2. Mixing reinforcing fibers and additives: mixing the base material with reinforcing fibers, water retaining agent, organic fertilizer and microbial carrier; S3, melt blending: adding the molten degradable polymer binder, stirring at 100-200 rpm for 10-20 minutes at 160-180°C; S4, functional treatment: dissolving the plant growth promoter and spraying it on the surface of the mixture; S5. Molding and curing: Add appropriate amount of water to adjust the humidity, press and shape at a pressure of 5-10MPa, and cure at room temperature or 40-60℃ for 12-48 hours.

7. The ecological restoration composite material according to claim 6, characterized in that: In S1, a weak alkaline solution is used to clean the natural fiber, the drying temperature is 50-70° C., and the drying time is 2-4 hours.

8. The ecological restoration composite material according to claim 6, characterized in that: The loading amount of the plant growth promoter in S4 is 3-8% of the total weight of the composite material. After spraying, the plant growth promoter is dried at 40-60° C. for 2-4 hours under ventilation.

9. The ecological restoration composite material according to claim 6, characterized in that: In S5, ultraviolet radiation or a chemical crosslinking agent is used for crosslinking, and the crosslinking agent is citric acid or glutaraldehyde, the crosslinking temperature is 25-60° C., and the treatment time is 1-3 hours.