Multifunctional biodegradable environment-friendly liquid mulching film

Abstract

The invention discloses a multifunctional biodegradable environment-friendly liquid mulching film which comprises a cellulose matrix, a photo-thermal response filler, a microbial filler, a dynamic cross-linking agent, a farmland modifier and a growth aid, the cellulose matrix is a nanocellulose suspension, the diameter of the cellulose matrix is 1-100nm, and the dynamic cross-linking agent is a complex of oxidized konjac glucomannan and Fe < 3 + > ions; the photo-thermal response filler comprises one or more of black phosphorus quantum dots or carbon quantum dots, the particle size of the photo-thermal response filler is 3-10 nm, the farmland modifier is humic acid grafted cellulose nanowhiskers, and the grafting rate is larger than 30%. Compared with the prior art, the multifunctional biodegradable environment-friendly liquid mulching film has the advantages that the multifunctional biodegradable environment-friendly liquid mulching film is easy to produce and use, reduces environmental pollution and can be naturally degraded.

Description

Technical Field

[0001] The present invention relates to the technical field of agricultural product planting accessories, and specifically refers to a multifunctional biodegradable environmentally friendly liquid film for farmland. Background Art

[0002] The use of agricultural film cultivation technology can coordinate the relationship between heat, light, water, air, fertilizer and crops, create a good ecological environment for crop growth, promote early ripening of crops, improve crop quality, and increase production and income significantly, so it is widely used in agricultural production.

[0003] At present, polyethylene film is mostly used in film cultivation technology. However, after being used for a period of time, this kind of film is easy to break and cannot dissolve in the soil by itself, thus seriously damaging the soil quality, bringing white pollution and causing crop production reduction. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the above technical defects and provide a multifunctional biodegradable environmentally friendly liquid film for farmland that is easy to produce and use, reduces environmental pollution, and can be naturally degraded.

[0005] To solve the above technical problem, the technical solution provided by the present invention is: a multifunctional biodegradable environmentally friendly liquid film for farmland, comprising a cellulose matrix, a photothermal response filler, a microbial filler, a dynamic crosslinking agent, a farmland soil conditioner, and a growth promoter;

[0006] The cellulose matrix is a nanofibrillated cellulose suspension with a diameter of 1-100 nm, and the dynamic crosslinking agent is an ion complex of oxidized konjac glucomannan and Fe 3+ ions;

[0007] The photothermal response filler includes one or a combination of black phosphorus quantum dots or carbon quantum dots, with a particle size of 3-10 nm, and the farmland soil conditioner is cellulose nanocrystals grafted with humic acid, and the grafting rate > 30%.

[0008] Preferably, it further includes trace elements for planting, including chelated Zn 2+ (0.1-0.5 wt%), Mn 2+ (0.05-0.2 wt%), and Cu 2+ (0.01-0.1 wt%).

[0009] Preferably, the microbial filler includes one or a combination of Bacillus thuringiensis, Bacillus thuringiensis var. tenebrionis, Bacillus popilliae, Bacillus sphaericus, Beauveria bassiana, and Bacillus clausii.

[0010] Preferably, the farmland soil conditioner further includes a complex of humic acid and γ-polyglutamic acid, and the particle size of the complex ≤ 200 nm.

[0011] Preferably, the growth promoter comprises a copolymer of polyglutamic acid and chitosan oligosaccharide.

[0012] Preferably, the oxidized konjac glucomannan and Fe 3+ have a molar ratio of 5-10:1.

[0013] Preferably, the nanocellulose suspension is obtained by high-pressure homogenization after pretreatment of bamboo fibers with alkali or urea, and is dynamically crosslinked to form a three-dimensional gradient porous network structure.

[0014] On the other hand, the present invention discloses a preparation method of a biodegradable environmental protection liquid film for farmland, comprising the following steps:

[0015] S1: Preparation of nanocellulose matrix;

[0016] S2: Synthesis of dynamic crosslinking agent;

[0017] S3: Immobilization of microbial fillers, adding photothermal-responsive fillers, microbial fillers, farmland improvers and growth promoters;

[0018] S4: Preparation of liquid film for farmland, mixing nanocellulose matrix and functional fillers, and obtaining a sprayable environmental protection film for farmland after homogenization.

[0019] The advantages of the present invention compared with the prior art are as follows: In the present invention, the need for conventional film for farmland is met by means of the film-forming ability of the cellulose matrix. After forming a complex with Fe 3+ ions, the crosslinking effect further increases the structural stability of the film body. At the same time, both cellulose and konjac glucomannan are natural polymer materials and have biodegradability. By adding various functional fillers, the functional requirements for the film for farmland are met. Brief Description of the Drawings

[0020] Figure 1 is a schematic diagram of the production process of the liquid film for farmland. Detailed Embodiments

[0021] The following further describes the detailed embodiments of the present invention, and clearly and completely describes the technical solutions in the embodiments of the present invention.

[0022] A multifunctional biodegradable environmental protection liquid film for farmland, comprising a cellulose matrix, a photothermal-responsive filler, a microbial filler, a dynamic crosslinking agent, a farmland improver and a growth promoter; the cellulose matrix is a nanocellulose suspension with a diameter of 1-100 nm, and the dynamic crosslinking agent is an ion complex of oxidized konjac glucomannan and Fe 3+ ions; the photothermal-responsive filler comprises one or a combination of black phosphorus quantum dots or carbon quantum dots, with a particle size of 3-10 nm, and the farmland improver is cellulose nanocrystals grafted with humic acid, and the grafting rate > 30%.

[0023] In specific use, it also includes trace elements for planting, including chelated Zn 2+ (0.1 - 0.5 wt%), Mn 2+ (0.05 - 0.2 wt%) and Cu 2+ (0.01 - 0.1 wt%) to meet the nutrient requirements for planting in agricultural land.

[0024] The microbial filler includes one or a combination of several of Bacillus thuringiensis, Bacillus thuringiensis var. galleriae, Bacillus popilliae, Bacillus sphaericus, Beauveria bassiana, and Bacillus clausii, and is adjusted for use according to the situation of agricultural land.

[0025] The agricultural land conditioner also includes a complex of humic acid and γ - polyglutamic acid, with the particle size of the complex ≤ 200 nm, and the growth promoter includes a copolymer of polyglutamic acid and chitosan oligosaccharide.

[0026] During use, the molar ratio of oxidized konjac glucomannan to Fe 3+ is 5 - 10:1.

[0027] The nanocellulose suspension is obtained by high - pressure homogenization after pretreating bamboo fibers with alkali or urea, and forms a three - dimensional gradient porous network structure through dynamic cross - linking.

[0028] The specific steps are as follows:

[0029] S1: Preparation of nanocellulose matrix;

[0030] S2: Synthesis of dynamic cross - linker;

[0031] S3: Immobilization of microbial filler, adding photothermal response filler, microbial filler, agricultural land conditioner and growth promoter;

[0032] S4: Preparation of liquid mulch film, mixing nanocellulose matrix and functional filler, and obtaining a sprayable environmental - friendly mulch film after homogenization.

[0033] More specifically:

[0034] Crush bamboo fibers to 2 - 5 mm, soak them in an 8% NaOH or 12% urea mixture (mass ratio 1:1), freeze at - 15 °C for 12 hours and then thaw, and obtain a nanocellulose suspension with a diameter of 1 - 100 nm through high - pressure homogenization treatment. Select black phosphorus bulk, ball - mill it to a particle size ≤ 50 μm, ultrasonically exfoliate it to obtain a BPQDs stock solution, and coat the surface with polydopamine to form a complex;

[0035] Dissolve konjac glucomannan in water, add NaIO4 for dialysis purification, add FeCl3 solution and stir magnetically for 2 h to form a cross - linker, continue to encapsulate the microbial filler, fill the agricultural land conditioner and growth promoter to form a matrix solution, and use a high - pressure spraying device to spray and dry naturally to form a mulch film;

[0036] Specifically, a cross-linking agent of the nanocellulose suspension is fused and homogenously stirred to form a matrix phase, and various functional agents are added and stirred and mixed.

[0037] The content not detailedly described in this specification belongs to the prior art well-known to those skilled in the art.

[0038] The above describes the present invention and its implementation manners. Such description is not restrictive. What is shown in the drawings is only one of the implementation manners of the present invention, and the actual structure is not limited thereto. Generally speaking, if those of ordinary skill in the art are inspired by it and, without departing from the gist of the present invention, creatively design structural manners and embodiments similar to the technical solution, they shall fall within the protection scope of the present invention.

Claims

1. A multifunctional biodegradable environmental protection liquid mulch film, characterized in that: It includes a cellulose matrix, a photothermal response filler, a microbial filler, a dynamic crosslinking agent, a farmland improver, and a growth promoter; The cellulose matrix is a nanocellulose suspension with a diameter of 1 - 100 nm, and the dynamic crosslinking agent is an ion complex of oxidized konjac glucomannan and Fe 3+ ions; The photothermal response filler includes one or a combination of black phosphorus quantum dots or carbon quantum dots, with a particle size of 3-10 nm. The farmland improver is cellulose nanocrystals grafted with humic acid, and the grafting rate is >30%.

2. The multifunctional biodegradable environmental protection liquid film according to claim 1, characterized in that: It also includes trace elements for planting, including chelated Zn 2+ (0.1 - 0.5 wt%), Mn2 + (0.05 - 0.2 wt%) and Cu 2+ (0.01 - 0.1 wt%).

3. A multifunctional biodegradable environmental protection liquid mulch film according to claim 1, characterized in that: The microbial filler includes one or a combination of Bacillus thuringiensis, Bacillus thuringiensis var. galleriae, Bacillus popilliae, Bacillus sphaericus, Beauveria bassiana, and Bacillus clausii.

4. A multifunctional biodegradable environmental protection liquid film mulch according to claim 1, characterized in that: The farmland improver also includes a complex of humic acid and γ-polyglutamic acid, and the particle size of the complex is ≤200 nm.

5. A multifunctional biodegradable environmental protection liquid mulching film according to claim 1, characterized in that: The growth promoter includes a copolymer of polyglutamic acid and chitosan oligosaccharide.

6. A multifunctional biodegradable and environmentally friendly liquid mulching film according to claim 1, characterized in that: The molar ratio of the oxidized konjac glucomannan to Fe 3+ is 5 to 10:

1.

7. A multifunctional biodegradable environmental protection liquid mulching film according to claim 1, characterized in that: The nanofibrillated cellulose suspension is obtained by high-pressure homogenization after the bamboo fiber is pretreated with alkali or urea, and a three-dimensional gradient porous network structure is formed by dynamic crosslinking.

8. A preparation method of a biodegradable environmental protection liquid film mulch, which is applied to a multifunctional biodegradable environmental protection liquid film mulch according to any one of claims 1-7, characterized in that: It includes the following steps: S1: Preparation of the nanofibrillated cellulose matrix; S2: Synthesis of the dynamic crosslinking agent; S3: Immobilization of the microbial filler, and addition of the photothermal response filler, the microbial filler, the farmland improver, and the growth promoter; S4: Preparation of the liquid mulch film, mixing the nanofibrillated cellulose matrix and the functional filler, and obtaining a sprayable environmentally friendly mulch film after homogenization.

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