阅读说明：本技术 一种用浒苔和海带制备的干地膜及制备方法 (Dry mulching film prepared from enteromorpha and kelp and preparation method thereof ) 是由 许加超 赵芸 邓小雪 付晓婷 高昕 毛相召 于 2018-11-19 设计创作，主要内容包括：本发明的目的是提供一种用浒苔和海带制备的干地膜及制备方法。本发明以浒苔和褐藻类海藻为原料,采用M-H<Sup>+</Sup>混合交联技术,制备的一种生物全降解的浒苔和海带混合干地膜,不仅实现了变废为宝,保护了生态及生活环境,而且也为浒苔深加工的综合利用开辟了一条崭新的道路。该膜不仅具有塑料地膜的保墒、保水等作用,同时保留了浒苔和褐藻类海藻中所有活性成分如海藻多糖、海藻蛋白、维生素、脂肪酸、海藻酶、海藻酚及大量的中微量元素,有机物被土壤微生物降解后,变成小分子活性物质,是一种良好的有机肥料,能够改善土壤环境,修复土壤,促进农作物生长发育。(The invention aims to provide a dry mulching film prepared from enteromorpha and kelp and a preparation method thereof. The invention takes enteromorpha and brown algae as raw materials and adopts M-H + The prepared biological fully-degradable enteromorpha and kelp mixed dry mulching film not only realizes changing waste into valuable and protects ecological and living environment, but also opens up a new way for comprehensive utilization of deep processing of enteromorpha. The film not only has the functions of soil moisture conservation, water conservation and the like of the plastic mulching film, but also retains all active ingredients in enteromorpha and brown algae such as algal polysaccharides, algal proteins and vitaminsThe organic matters are degraded by soil microorganisms to become micromolecular active substances, and the organic fertilizer is a good organic fertilizer and can improve the soil environment, repair the soil and promote the growth and development of crops.)

1. The enteromorpha and kelp mixed dry mulching film is characterized in that the preparation method of the enteromorpha and kelp mixed dry mulching film comprises the following steps:

1) soaking and washing the enteromorpha prolifera and the kelp in fresh water;

2) adding water which is 10-40 times of the weight of the clean enteromorpha prolifera and the clean kelp in the step 1), and adding sodium carbonate which is 5-20% of the weight of the enteromorpha prolifera and the clean kelp in the step 1); processing at 50-90 ℃ to obtain mixed viscous slurry of enteromorpha prolifera and kelp;

3) adding a softening agent and a plasticizer into the mixed viscous slurry obtained in the step 2), uniformly stirring, passing through a colloid mill, and degassing to prepare an enteromorpha and kelp uniformly-mixed slurry, wherein the viscosity of the enteromorpha and kelp uniformly-mixed slurry is 50-50000 mPas;

4) carrying out tape casting and film laying on the slurry obtained by uniformly mixing the enteromorpha prolifera and the kelp in the step 3), drying the film until the moisture content is less than 60%, and cooling to obtain a water-soluble semi-dry film of the enteromorpha prolifera and the kelp;

5) mixing the water-soluble enteromorpha prolifera and the kelp obtained in the step 4) to obtain a mixed semi-dry film, and soaking the mixed semi-dry film in M-H⁺And (3) crosslinking the mixed solution to form a water-insoluble enteromorpha prolifera and kelp mixed gel film, and then carrying out bleaching by using a bleaching agent, washing by using water and drying at a low temperature to obtain the enteromorpha prolifera and kelp mixed dry mulching film.

2. The enteromorpha and kelp mixed dry mulching film according to claim 1, wherein the mass ratio of the enteromorpha to the kelp is 1-10: 1.

3. The enteromorpha and kelp mixed dry mulching film according to claim 1, wherein the softener is 0.001-10% by mass of the mixed slurry of the enteromorpha and the kelp.

4. The enteromorpha and kelp mixed dry mulching film according to claim 1 or 3, wherein the softener is locust bean gum, modified cellulose, gellan gum, chitosan, konjac gum, agar, carrageenan, ghatti gum, pectin, karaya gum, xanthan gum, expected jean gum or guar gum.

5. The enteromorpha and kelp mixed dry mulching film according to claim 1, wherein the mass percentage of the plasticizer in the mixed slurry of the enteromorpha and the kelp is 0.001-10%.

6. The enteromorpha and kelp mixed dry mulching film according to claim 1 or 5, wherein the plasticizer is glycerol, cocoa butter, vaseline, cholesterol, triglyceride, palmitic acid, myristic acid and stearic acid, gelatin or animal oil.

7. The enteromorpha and kelp mixed dry mulching film according to claim 1, wherein the step 5) of low-temperature drying is performed at a temperature of not higher than 50 ℃.

8. The enteromorpha and kelp mixed dry mulching film according to claim 1, wherein the M-H is⁺The mixed solution refers to an acidic mixed solution containing divalent or trivalent metal ion salts; the divalent or trivalent metal ion salt is Ga²⁺、Zn²⁺、Mn⁺²、Al³⁺Or Fe³⁺Salt, wherein the concentration of the salt in the mixed solution is 0.1-10%; the acidic mixed solution comprises inorganic acid or organic acid, and the concentration of the inorganic acid or organic acid is 0.1-10%.

9. The enteromorpha and kelp mixed dry mulching film according to claim 1, wherein the bleaching agent is sodium hypochlorite or hydrogen peroxide.

Technical Field

The invention belongs to the technical field of mulching film preparation, and particularly relates to a dry mulching film prepared from enteromorpha and kelp and a preparation method of the dry mulching film.

Technical Field

The plastic white pollution of soil is a worldwide problem, the plastic mulching film coverage area of field crops and fruit trees in China reaches more than 5 hundred million mu, the using amount of the plastic mulching film currently exceeds 230 ten thousand tons, the degradation time of the plastic mulching film reaches two or three hundred years, the minister and minister of the white revolution of sunday gradually changes to white pollution, the plastic residual film in the soil can reach 497 Kg/mu at most, so that the yield of grains is greatly reduced, the yield of corn is reduced by 10 percent, the yield of wheat is reduced by 2 to 3 percent, the yield of cotton is reduced by 10 to 23 percent, the yield of vegetables is reduced by 14.6 to 59.2 percent, and all countries in the world strive to seek a substitute

The enteromorpha prolifera is rich in carbohydrates such as enteromorpha prolifera polysaccharide and the like, protein, crude fiber and mineral substances, and also contains fat and vitamins, so that ecological hazards can be generated due to outbreak of the enteromorpha prolifera, the enteromorpha prolifera which is propagated in large quantities shields sunlight and influences the growth of submarine algae, and dead enteromorpha prolifera can also consume oxygen in seawater and can cause adverse effects on other marine organisms.

Disclosure of Invention

The invention aims to provide the dry mulching film prepared from the enteromorpha prolifera and the kelp and the preparation method thereof, and opens up a new way for the deep processing of the enteromorpha prolifera and the kelp, thereby not only solving the ecological harm of the enteromorpha prolifera, but also solving the problem of white pollution caused by plastic mulching films, restoring the soil environment and reducing the production cost of the seaweed mulching film.

The enteromorpha and kelp mixed dry mulching film provided by the invention is prepared by the following method:

1) soaking and washing the enteromorpha prolifera and the kelp in fresh water;

2) adding water which is 10-40 times of the weight of the clean enteromorpha prolifera and the clean kelp in the step 1), and adding sodium carbonate which is 5-20% of the weight of the enteromorpha prolifera and the clean kelp in the step 1); processing at 50-90 ℃ to obtain mixed viscous slurry of enteromorpha prolifera and kelp;

3) adding a softening agent and a plasticizer into the mixed viscous slurry obtained in the step 2), uniformly stirring, passing through a colloid mill, and degassing to prepare an enteromorpha and kelp uniformly-mixed slurry, wherein the viscosity of the enteromorpha and kelp uniformly-mixed slurry is 50-50000 mPas;

4) carrying out tape casting and film laying on the slurry obtained by uniformly mixing the enteromorpha prolifera and the kelp in the step 3), drying the film until the moisture content is less than 60%, and cooling to obtain a water-soluble semi-dry film of the enteromorpha prolifera and the kelp;

5) mixing the water-soluble enteromorpha prolifera and the kelp obtained in the step 4) to obtain a mixed semi-dry film, and soaking the mixed semi-dry film in M-H⁺And (3) crosslinking the mixed solution to form a water-insoluble enteromorpha prolifera and kelp mixed gel film, and then carrying out bleaching by using a bleaching agent, washing by using water and drying at a low temperature to obtain the enteromorpha prolifera and kelp mixed dry mulching film.

The mass ratio of the enteromorpha prolifera to the kelp is 1-10: 1;

the mass percentage of the softening agent in the mixed slurry of the enteromorpha prolifera and the kelp is 0.001-10%, and the softening agent is preferably locust bean gum, modified cellulose, gellan gum, chitosan, konjac gum, agar, carrageenan, ghatti gum, pectin, karaya gum, xanthan gum, expected jean gum or guar gum.

The mass percentage of the plasticizer in the mixed slurry of the enteromorpha prolifera and the kelp is 0.001-10%, and glycerol, cocoa oil, vaseline, cholesterol, triglyceride, palmitic acid, myristic acid, stearic acid, gelatin or animal fat are preferably selected.

The step 5) low-temperature drying process refers to a process that the temperature is not higher than 50 ℃;

M-H as described above⁺The mixed solution refers to an acidic mixed solution containing divalent or trivalent metal ion salts; the divalent or trivalent metal ion salt is Ga²⁺、Zn²⁺、Mn⁺²、Al³⁺Or Fe³⁺A salt having a concentration of 0.1 to 10% (w/w) in the mixed solution; the acidic mixed solution comprises inorganic acid or organic acid, and the concentration of the inorganic acid or organic acid is 0.1-10% (v/v).

The bleaching agent is sodium hypochlorite or hydrogen peroxide.

The invention takes enteromorpha and brown algae as raw materials and adopts M-H⁺The prepared biological fully-degradable enteromorpha and kelp mixed dry mulching film not only realizes changing waste into valuable and protects ecological and living environment, but also opens up a new way for comprehensive utilization of deep processing of enteromorpha. The film not only has the functions of soil moisture conservation, water conservation and the like of the plastic mulching film, but also retains all active ingredients in enteromorpha and brown algae such as algal polysaccharides, algal proteins, vitamins, fatty acids, trehalase, seaweed phenols and a large amount of medium and trace elements, organic matters are degraded by soil microorganisms to become small molecular active substances, and the film is a good organic fertilizer, can improve the soil environment, repair the soil and promote the growth and development of crops.

Drawings

FIG. 1: influence graph of fungi on the weight of the mulching film;

FIG. 2: influence graph of bacteria on the weight of the mulching film;

FIG. 3: influence of actinomycetes on the weight of the mulching film.

Detailed Description

The invention relates to a preparation method of a dry mixed mulching film of enteromorpha prolifera and kelp, which comprises the following steps:

(1) weighing quantitative dry Enteromorpha prolifera and dry kelp, soaking in fresh water, washing, and removing sand, salt and impurities;

(2) mixing the enteromorpha cleaned in the step (1) with the kelp, adding water 10-40 times the weight of the mixed kelp, adding 5-20% of sodium carbonate, and heating at 50-90 ℃ for 1.0-6.0 hours to obtain mixed viscous slurry of the enteromorpha and the kelp;

(3) adding a softening agent and a plasticizer which are 0.001-50% of the mixed seaweed weight into the mixed slurry of the enteromorpha prolifera and the kelp obtained in the step (2), uniformly stirring, passing through a colloid mill, degassing, and keeping the viscosity of the slurry between 50-50000 mPas;

(4) casting and paving a film on the mixed slurry of the enteromorpha prolifera and the kelp obtained in the step (3) on a mould, drying the film at the temperature of 20-100 ℃ until the moisture content is less than 60%, and cooling to obtain a water-soluble mixed semi-dry film of the enteromorpha prolifera and the kelp;

(5) and (3) soaking the mixed semi-dry film of the water-soluble enteromorpha prolifera and the kelp obtained in the step (4) in an M-H + mixed solution for crosslinking for 2-100 minutes to form a mixed gel film of the water-insoluble enteromorpha prolifera and the kelp, and then carrying out bleaching by using a bleaching agent, washing by water, and drying at a low temperature to obtain the mixed dry mulching film of the enteromorpha prolifera and the kelp.

The enteromorpha used in the invention is a wild seaweed, and is easy to form ecological hazards. The enteromorpha prolifera is rich in carbohydrates such as enteromorpha prolifera polysaccharide, proteins, crude fibers and mineral substances, and also contains fat and vitamins, but is easy to dissolve in water after film forming and is not suitable for being independently used as a dry mulching film.

The brown algae such as kelp and the like are rich in sodium alginate and have good film forming property, the content of the sodium alginate contained in the kelp in the mixed slurry of the enteromorpha and the kelp is 0.1-25%, if the content of the sodium alginate is less than 0.1%, the compatibility of the sodium alginate and enteromorpha polysaccharide is poor, the synergistic effect is not strong, and the formed dry mixed mulching film of the enteromorpha and the kelp is small in strength and easy to damage; if the content of sodium alginate is more than 25%, the viscosity of the slurry is too high to be filmed.

The sodium carbonate can also be sodium oxalate; one of the functions is to break cellulose cell walls of enteromorpha so as to increase the mechanical property of the mixed dry mulching film of enteromorpha and kelp; the second function is to break the cell wall of the sea tangle, and react the polysaccharide, protein, crude fiber and mineral substance of the sea tangle with the content of the sea tangle to form a compact three-dimensional reticular gel structure, so as to increase the mechanical property and material property of the membrane.

The softening agent is used for increasing the softness of the mixed semi-dry film of the enteromorpha prolifera and the kelp, improving the softness and elongation at break of the film and facilitating field operation; the plasticizer is used for improving the water retention property and the flexibility of the film;

the viscosity of the mixed slurry of the enteromorpha prolifera and the kelp is controlled to be 50-50000 mPas because if the viscosity is less than 50mPas, the solution is too thin, the formed film is too thin, the mechanical property and the technical index are greatly reduced, the operability is avoided, and if the viscosity is more than 50000mPas, the solution is too thick and the film cannot be laid;

said M-H⁺The mixed crosslinking aims to prepare the enteromorpha and kelp mixed dry mulching film with ideal toughness and strength, overcomes the brittleness of strong gel caused by singly using 2-valent metal ions M for crosslinking, and also overcomes the phenomena that the matrix structure of singly using acid for crosslinking is discontinuous, a discontinuous fault structure appears inside the film, and the mechanical property of the film is not ideal.

The enteromorpha and kelp mixed dry mulching film obtained by the invention has good technical indexes and meets the requirement of mechanical mulching. The technical indexes are as follows:

more than 91.6 percent of organic matter, 15 to 20 percent of water content, less than 120 percent of water absorption expansion rate, less than 10 percent of light transmittance, more than 45Mpa of tensile strength, 5.0 to 9.0 percent of elongation at break, less than 3.0 percent of water solubility and 100 percent of soil microbial degradation rate.

The method for preparing the mixed dry mulching film of enteromorpha prolifera and kelp is described in detail with reference to specific examples.