阅读说明：本技术 一种可降解地膜及其制备方法 (Degradable mulching film and preparation method thereof ) 是由 周伟祥 王希洋 于 2020-12-15 设计创作，主要内容包括：本发明提供一种可降解地膜及其制备方法,由以下重量份数的原料制备而成：甘蔗残渣25-35份、土豆残渣15-25份、玉米秸秆15-25份、化学纤维10-15份、柠檬酸酯类增塑剂15-25份、防水剂3-8份、高分子聚合物粘合剂5-10份。本发明可降解地膜及其制备方法,选用甘蔗残渣、土豆残渣、玉米秸秆为原料可以有效利用植物残渣制备出具有较好的可降解性、胶质含量高、聚合能力强、延展性较好且具备相当的使用稳定性。根据本发明方法制得的地膜将植物废弃物进行了再利用,价格低廉,解决了环境污染和资源浪费的问题。(The invention provides a degradable mulching film and a preparation method thereof, wherein the degradable mulching film is prepared from the following raw materials in parts by weight: 25-35 parts of sugarcane residues, 15-25 parts of potato residues, 15-25 parts of corn straws, 10-15 parts of chemical fibers, 15-25 parts of citric acid ester plasticizers, 3-8 parts of waterproofing agents and 5-10 parts of high polymer adhesives. According to the degradable mulching film and the preparation method thereof, the sugarcane residues, the potato residues and the corn straws are selected as raw materials, so that the degradable mulching film has the advantages of good degradability, high colloid content, strong polymerization capability, good ductility and considerable use stability and can be prepared by effectively utilizing the plant residues. The mulching film prepared by the method recycles plant wastes, has low price, and solves the problems of environmental pollution and resource waste.)

1. A degradable mulching film is characterized in that: the feed is prepared from the following raw materials in parts by weight: 25-35 parts of sugarcane residues, 15-25 parts of potato residues, 15-25 parts of corn straws, 10-15 parts of chemical fibers, 15-25 parts of citric acid ester plasticizers, 3-8 parts of waterproofing agents and 5-10 parts of high polymer adhesives.

2. The degradable mulch film of claim 1, wherein: the feed is prepared from the following raw materials in parts by weight: 30 parts of sugarcane residues, 20 parts of potato residues, 20 parts of corn straws, 12 parts of chemical fibers, 19 parts of citrate plasticizer, 6 parts of waterproofing agent and 7 parts of high molecular polymer adhesive.

3. The degradable mulch film of claim 1, wherein: the chemical fiber is nitrate fiber and artificial protein fiber, and the weight ratio of the nitrate fiber to the artificial protein fiber is 1: 1.

4. The degradable mulch film of claim 1, wherein: the waterproof agent is acrylate emulsion or silica sol.

5. The degradable mulch film of claim 1, wherein: the high-molecular polymer adhesive is polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate is 1:2 in parts by weight.

6. The degradable mulch film of claim 1, wherein: the talcum powder and the wollastonite powder are mixed according to the weight ratio of 1:1, and the mixture also comprises 5-10 parts of talcum powder and wollastonite powder.

7. The degradable mulch film of claim 4, wherein: the talcum powder and the wollastonite powder are mixed according to the weight ratio of 1:1 to 8.

8. A method for preparing degradable mulching film according to any one of claims 1-5, wherein the method comprises the following steps: the method comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 80-100 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 80-100r/min for 30-50min to form mixed particles for later use;

(2) then putting the mixed particles prepared in the step (1) into a crusher to crush the mixed particles to have the particle size of 15-20mm, taking out the mixed particles to be put into a reactor, firstly adding the high molecular polymer adhesive, stirring and reacting for 20-30min, then adding the citrate plasticizer and the chemical fiber, continuously stirring and reacting for 20-30min, stirring the reactor at the temperature of 100 ℃ and 180 ℃ and at the rotation speed of 100 ℃ and 150r/min to prepare film-forming mixed slurry;

(3) preparing the film-forming mixture slurry into a mulching film;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

9. The preparation method of the degradable mulching film according to claim 8, wherein the degradable mulching film comprises the following steps: in the step (2), talcum powder and wollastonite powder are added together with the citrate plasticizer and the chemical fiber.

10. The preparation method of the degradable mulching film according to claim 8, wherein the degradable mulching film comprises the following steps: preparing the film-forming mixture slurry into a mulching film by adopting a film-forming process in the step (3); the film forming process comprises blow molding or film forming by using a film supporting material as a framework.

Technical Field

The invention relates to the field of biological materials, in particular to a degradable mulching film and a preparation method thereof.

Background

The mulching film is used for ground covering to improve the soil temperature, maintain the soil moisture, maintain the soil structure, prevent pests from attacking crops and diseases caused by certain microorganisms and the like, and has the function of promoting the growth of plants. The currently used agricultural film takes chemical fibers as raw materials, the main components of the agricultural film are polypropylene, polyethylene and polyvinyl chloride, the agricultural film can be left in the field for decades without degradation, and broken films are accumulated on a soil plough layer year by year after being used for years, so that soil hardening, permeability deterioration, root growth obstruction and yield reduction of succeeding crops are caused.

The plant fiber mulching film is applied more in production at present. The mulching film is prepared by using plant fibers as raw materials through proper processing, and the plant fiber mulching film has wide material sources, good biodegradability, environmental protection and soil fertility improvement characteristics, so the plant fiber mulching film becomes the development trend of the future mulching film. This has become a common consensus in the world at home and abroad. The straw pulp mulching film in the plant fiber applied in the prior production is mainly prepared by grinding straws or plant residues of wheat straws, pasture, straws and the like into straw pulp by a pulper, adding additives into the straw pulp, and preparing the straw pulp mulching film into the mulching film for use.

Therefore, it is very necessary to develop a degradable mulching film with high colloid content, strong polymerization capability and good ductility and a preparation method thereof.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the degradable mulching film and the preparation method thereof, and the degradable mulching film with high colloid content, strong polymerization capacity and better ductility can be prepared by effectively utilizing plant residues by selecting the sugarcane residues, the potato residues and the corn straws as raw materials.

The technical scheme of the invention is realized as follows:

the degradable mulching film is prepared from the following raw materials in parts by weight: 25-35 parts of sugarcane residues, 15-25 parts of potato residues, 15-25 parts of corn straws, 10-15 parts of chemical fibers, 15-25 parts of citric acid ester plasticizers, 3-8 parts of waterproofing agents and 5-10 parts of high polymer adhesives. The potato residues are waste materials such as potato skins and residual potato blocks, and the sugarcane residues are waste materials such as sugarcane skins and residual sugarcane residues.

Preferably, the feed is prepared from the following raw materials in parts by weight: 30 parts of sugarcane residues, 20 parts of potato residues, 20 parts of corn straws, 12 parts of chemical fibers, 19 parts of citrate plasticizer, 6 parts of waterproofing agent and 7 parts of high molecular polymer adhesive.

Preferably, the chemical fibers are nitrate fibers and artificial protein fibers, and the weight part ratio of the nitrate fibers to the artificial protein fibers is 1: 1.

Preferably, the coating also comprises 5-10 parts of talcum powder and wollastonite powder, wherein the weight part ratio of the talcum powder to the wollastonite powder is 1: 1.

Preferably, 8 parts of talcum powder and 8 parts of wollastonite powder are further included, and the weight part ratio of the talcum powder to the wollastonite powder is 1: 1.

Preferably, the water repellent is acrylate emulsion or silica sol.

Preferably, the high molecular polymer binder is polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate is 1:2 by weight.

A preparation method of the degradable mulching film comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 80-100 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 80-100r/min for 30-50min to form mixed particles for later use;

(2) then putting the mixed particles prepared in the step (1) into a crusher to crush the mixed particles to have the particle size of 15-20mm, taking out the mixed particles to be put into a reactor, firstly adding the high molecular polymer adhesive, stirring and reacting for 20-30min, then adding the citrate plasticizer and the chemical fiber, continuously stirring and reacting for 20-30min, stirring the reactor at the temperature of 100 ℃ and 180 ℃ and at the rotation speed of 100 ℃ and 150r/min to prepare film-forming mixed slurry;

(3) preparing the film-forming mixture slurry into a mulching film;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

Preferably, the step (2) is added with the citrate plasticizer and the chemical fiber simultaneously with the talcum powder and the wollastonite powder.

Preferably, in the step (3), the film-forming mixture slurry is prepared into the mulching film by adopting a film-forming process; the film forming process comprises blow molding or film forming by using a film supporting material as a framework.

The invention has the following beneficial effects:

the degradable mulching film prepared by the invention is prepared by adopting sugarcane residues, potato residues and corn straws as main raw materials, and has the advantages of good degradability, high colloid content, strong polymerization capability, good ductility and considerable use stability. The mulching film prepared by the method recycles plant wastes, has low price, and solves the problems of environmental pollution and resource waste.

Detailed Description

For a more clear understanding of the technical features, objects and advantages of the present invention, reference is now made to the following detailed description of the embodiments of the present invention taken in conjunction with the accompanying drawings, which are included to illustrate and not to limit the scope of the present invention.

Example 1

The degradable mulching film is prepared from the following raw materials in parts by weight: 30 parts of sugarcane residues, 20 parts of potato residues, 20 parts of corn straws, 6 parts of nitrate fibers, 6 parts of artificial protein fibers, 19 parts of citrate plasticizer, 6 parts of waterproof agent acrylate emulsion, 7 parts of high polymer adhesive, 4 parts of talcum powder and 4 parts of wollastonite powder, wherein the high polymer adhesive is polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate in parts by weight is 1: 2. The potato residues are waste materials such as potato skins and residual potato blocks, and the sugarcane residues are waste materials such as sugarcane skins and residual sugarcane residues.

A preparation method of the degradable mulching film comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 90 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 90r/min for 40min to form mixed particles for later use;

(2) putting the mixed particles prepared in the step (1) into a grinder to be ground into particles with the particle size of 18mm, taking out the particles and putting the particles into a reactor, adding a high-molecular polymer adhesive, stirring and reacting for 25min, then adding a citrate plasticizer, talcum powder, wollastonite powder, nitrate fiber and artificial protein fiber, continuously stirring and reacting for 25min, wherein the stirring temperature of the reactor is 150 ℃, and the stirring speed is 120/min, so as to prepare film-forming mixed slurry;

(3) preparing the film-forming mixture slurry into a mulching film by adopting blow molding;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

Example 2

The degradable mulching film is prepared from the following raw materials in parts by weight: 25 parts of sugarcane residue, 25 parts of potato residue, 15 parts of corn straw, 7.5 parts of nitrate fiber, 7.5 parts of artificial protein fiber, 15 parts of citrate plasticizer, 8 parts of waterproof agent silica sol, 5 parts of high polymer adhesive, 5 parts of talcum powder and 5 parts of wollastonite powder. The high-molecular polymer adhesive is polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate is 1:2 in parts by weight. The potato residues are waste materials such as potato skins and residual potato blocks, and the sugarcane residues are waste materials such as sugarcane skins and residual sugarcane residues.

A preparation method of the degradable mulching film comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 80 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 100r/min for 30min to form mixed particles for later use;

(2) putting the mixed particles prepared in the step (1) into a grinder to be ground into particles with the particle size of 150mm, taking out the particles and putting the particles into a reactor, adding a high-molecular polymer adhesive, stirring and reacting for 30min, then adding a citrate plasticizer, talcum powder, wollastonite powder, nitrate fiber and artificial protein fiber, continuously stirring and reacting for 20min, wherein the stirring temperature of the reactor is 180 ℃, and the stirring speed is 100r/min, so as to prepare film-forming mixed slurry;

(3) film forming is carried out by adopting a film supporting material as a framework, and the film forming mixture slurry is prepared into a mulching film;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

Example 3

The degradable mulching film is prepared from the following raw materials in parts by weight: 35 parts of sugarcane residues, 15 parts of potato residues, 25 parts of corn straws, 5 parts of nitrate fibers, 5 parts of artificial protein fibers, 25 parts of citric acid ester plasticizers, 3 parts of waterproof agent acrylate emulsion, 10 parts of high polymer adhesives, 2.5 parts of talcum powder and 2.5 parts of wollastonite powder, wherein the high polymer adhesives are polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate is 1:2 by weight. The potato residues are waste materials such as potato skins and residual potato blocks, and the sugarcane residues are waste materials such as sugarcane skins and residual sugarcane residues.

A preparation method of the degradable mulching film comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 100 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 80r/min for 50min to form mixed particles for later use;

(2) putting the mixed particles prepared in the step (1) into a grinder to be ground into particles with the particle size of 20mm, taking out the particles and putting the particles into a reactor, adding a high-molecular polymer adhesive, stirring and reacting for 20min, then adding a citrate plasticizer, talcum powder, wollastonite powder, nitrate fiber and artificial protein fiber, continuously stirring and reacting for 30min, wherein the stirring temperature of the reactor is 100 ℃, and the stirring speed is 150r/min, so as to prepare film-forming mixed slurry;

(3) preparing the film-forming mixture slurry into a mulching film by adopting blow molding;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

Example 4

The degradable mulching film is prepared from the following raw materials in parts by weight: 32 parts of sugarcane residues, 24 parts of potato residues, 16 parts of corn straws, 6 parts of nitrate fibers, 6 parts of artificial protein fibers, 23 parts of citrate plasticizer, 7 parts of waterproof agent silica sol, 9 parts of high polymer adhesive, 3 parts of talcum powder and 3 parts of wollastonite powder. The high-molecular polymer adhesive is polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate is 1:2 in parts by weight. The potato residues are waste materials such as potato skins and residual potato blocks, and the sugarcane residues are waste materials such as sugarcane skins and residual sugarcane residues.

A preparation method of the degradable mulching film comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 90 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 90r/min for 40min to form mixed particles for later use;

(2) putting the mixed particles prepared in the step (1) into a grinder to be ground into particles with the particle size of 17mm, taking out the particles and putting the particles into a reactor, adding a high-molecular polymer adhesive, stirring and reacting for 23min, then adding a citrate plasticizer, talcum powder, wollastonite powder, nitrate fiber and artificial protein fiber, continuously stirring and reacting for 28min, wherein the stirring temperature of the reactor is 160 ℃, and the stirring speed is 135r/min, so as to prepare film-forming mixed slurry;

(3) film forming is carried out by adopting a film supporting material as a framework, and the film forming mixture slurry is prepared into a mulching film;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

Example 5

The degradable mulching film is prepared from the following raw materials in parts by weight: 32 parts of sugarcane residues, 24 parts of potato residues, 16 parts of corn straws, 6 parts of nitrate fibers, 6 parts of artificial protein fibers, 23 parts of citric acid ester plasticizers, 7 parts of waterproof agent silica sol and 9 parts of high polymer adhesives. The high-molecular polymer adhesive is polyethylene glycol and polyhydroxyalkanoate, and the ratio of the polyethylene glycol to the polyhydroxyalkanoate is 1:2 in parts by weight. The potato residues are waste materials such as potato skins and residual potato blocks, and the sugarcane residues are waste materials such as sugarcane skins and residual sugarcane residues.

A preparation method of the degradable mulching film comprises the following steps:

(1) weighing sugarcane residues, potato residues and corn straws in parts by weight, drying at 90 ℃ until the water content is 3-5%, and then putting the dried and dehydrated mixed raw materials of the sugarcane residues, the potato residues and the corn straws into a granulator for stirring at the stirring speed of 90r/min for 40min to form mixed particles for later use;

(2) putting the mixed particles prepared in the step (1) into a grinder to be ground into particles with the particle size of 17mm, taking out the particles and putting the particles into a reactor, adding a high-molecular polymer adhesive, stirring and reacting for 23min, then adding a citrate plasticizer, nitrate fibers and artificial protein fibers, continuously stirring and reacting for 28min, wherein the stirring temperature of the reactor is 160 ℃, and the stirring speed is 135r/min, so as to prepare film-forming mixed slurry;

(3) film forming is carried out by adopting a film supporting material as a framework, and the film forming mixture slurry is prepared into a mulching film;

(4) and (3) carrying out spraying waterproof treatment on the mulching film by using a waterproof agent.

Comparative example 1

The raw material ratio and preparation method of example 1 were adopted, with the only difference that there were no potato residue and corn stover, and the sugar cane residue increased from 30 parts to 70 parts.

Comparative example 2

The raw material ratio and preparation method of example 1 were adopted, with the only difference that there were no sugarcane residue and corn stover, and the potato residue increased from 20 parts to 70 parts.

Comparative example 3

The raw material ratio and preparation method of example 1 were adopted, with the only difference that there were no potato residue and sugarcane residue, and the corn stalks increased from the original 20 parts to 70 parts.

First, performance detection

The performances of the finished product prepared by the degradable mulching film and the preparation method thereof are tested according to the following method, and the results are shown in table 1: the thickness of the films was measured using a micrometer screw. Performing a film covering test on the prepared mulching film, burying 1 thermistor ground thermometer at a 10cm soil layer of each cell, and measuring the soil temperature to evaluate the heat preservation performance of the mulching film; and carrying out a soil burying test on the prepared mulching film, measuring the weight of the mulching film before and after degradation by adopting a weight reduction method, and calculating the loss rate of the mulching film to evaluate the degradability of the mulching film. Tensile strength: an electronic tensile tester is adopted, and the width of a test sample is 15mm, and the length of the test sample is 120 mm. Tensile strength formula: where σ is the tensile strength, F is the tensile value, and b is the cross-sectional area. Biodegradability: collecting and screening two soil samples of air-dried forest shrubbery meadow soil and forest soil by a 0.154mm sample separation sieve, and then weighing 40 g of soil samples and putting the soil samples into a brown bottle. Placing the soil and degradable mulching film sample into a culture flask, and simultaneously placing CO₂Absorbent (KOH), and then the culture flask was sealed and placed in a 20 ℃ incubator for culture. Organic matter in the sampleThe carbon dioxide gas generated by biodegradation is absorbed by KOH, and then diluted hydrochloric acid of 0.1mol/L is used for titration, thereby obtaining CO for ten weeks₂With the total amount of CO produced₂The amount of (a) to evaluate the degradability of the degradable mulch film.

TABLE 1

As can be seen from the examples and the comparative examples, the mulching film prepared by the method has better degradability on soil and has considerable use stability. The mulching film prepared by the method recycles plant wastes, has low price, and solves the problems of environmental pollution and resource waste.

The above embodiments are merely provided to help understand the method and core principle of the present invention, and the main steps and embodiments of the present invention are described in detail by using specific examples. To those skilled in the art, the various conditions and parameters may be varied as desired in a particular implementation in accordance with the principles of the invention, and in view of the foregoing, the description is not to be taken as limiting the invention.