KR101885099B1 - Mulching film with sterilzation and insecticidal effect and method of producing thereof - Google Patents

Abstract

The present invention relates to a mulching film having a sterilizing and insecticidal effect and a method for producing the mulching film and a biodegradable polymer having a polymerization degree of 1500 to 2000, a degree of saponification of 95 to 99.8% and a number average molecular weight of 50,000 to 80,000. Plasticizers; A crosslinking agent; Cellulose based resin; And a physiologically active substance having a sterilization and insecticidal effect. In comparison with the conventional polyethylene mulching film, the strength and elongation of the phosphorus are increased, and more than 90% is decomposed within 1 year after use. Can be adjusted. In addition, no separate collection is necessary, and pathogens derived from the soil can be blocked to prevent pests and diseases.

Description

TECHNICAL FIELD [0001] The present invention relates to a mulching film having sterilization and insecticidal effect, and a method for producing the mulching film.

The present invention relates to a mulching film having a sterilizing and insecticidal effect and a method for producing the mulching film. More specifically, the present invention relates to a mulching film containing a biodegradable polymer capable of regulating a decomposition period and includes a physiologically active substance having a sterilizing and insecticidal effect Which can block pathogens derived from soil from plants.

Transparent vinyl or black vinyl has been mainly used as an agricultural mulching material, but labor and labor required to be removed by hand after use is necessary and it is impossible to completely remove it. In addition, residual vinyl that has not been collected has polluted the soil by aggravating root growth and soil drainage of the next crop, and the environment of the rural area is becoming more and more wasted due to waste vinyl. In addition, over the last few decades, we have become obsessed with the economic aspect of productivity improvement, and the abuse of chemicals has made the agricultural environment more and more depraved.

There is a great deal of resistance problem that the effect of controlling the pesticide is low even when a large amount of pesticide is sprayed by continuous and continuous use of the pesticide. In addition, the pesticide which is often toxic in the agricultural product is detected more than the allowable value, And so forth. This results in various undesirable direct and indirect side effects. In particular, these side effects have a profound effect on those who are sensitive to chemicals or those who are physically weak. Therefore, there is a demand for development of a composition which is harmless to humans and the surrounding environment and can effectively remove pests.

Therefore, development of pesticides that are not toxic to humans or livestock and that do not act as pollutants in the environment is considered to be the maximum goal of pesticide researchers. However, since this is not easily accomplished, , Which is a synergistic combination of pesticides with other pesticides that can be used to reduce the use of pesticides in a variety of ways.

The basic undecomposed mulching film could be expected to improve thermal insulation and productivity, but it should be removed after use, and some of the existing mulching materials using wood pulp and import notices were too expensive to be used in general farms. We could expect uncomfortable price stability and single function of recycled paper.

As a method for solving the problems of the conventional mulching film, a mulching film for raw / photolytic agriculture such as Korean Patent Laid-Open No. 10-1996-0064953 has been developed. Biodegradable mulching film is different from conventional mulching film which had to be collected after use because the mulching film was completely decomposed within 1 year in the soil and could not be decomposed. However, even in the case of such a biodegradable mulching film, a separate pesticide preparation should be used in order to prevent pests and diseases of crops.

Therefore, it is urgent to develop a mulching film which can solve the environmental pollution problem due to the use of a separate pesticide preparation, and can control the decomposition period according to the crop to be cultivated.

Disclosed is a mulching film having sterilization and insecticidal effect, and a method for producing the mulching film.

It is an object of the present invention to provide a mulching film which is easy to use compared to conventional polyethylene mulching films by increasing tensile strength and elongation and decomposes by 90% or more within 1 year after use, The purpose.

It is another object of the present invention to provide a mulching film having sterilization and insecticidal effect, which can prevent pathogens derived from soil and prevent pests and diseases, and a method for producing the same.

Other objects and advantages of the present invention will become more apparent from the following detailed description of the invention and claims.

Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art, and the following embodiments can be modified into various other shapes, It is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more faithful and complete, and will fully convey the scope of the invention to those skilled in the art.

The biodegradable polymer of the present invention refers to a polymeric material which is metabolized by living organisms in a process of degradation and is converted into a low molecular weight compound. Ideal biodegradable polymers should exhibit excellent performance during use and should be degraded rapidly by natural microorganisms after disposal.

Generally, decomposition of a polymer by a microorganism is carried out by first hydrolyzing a chemical bond such as an ester bond, a glycoside bond and a peptide bond of a polymer by adsorbing a decomposition enzyme secreted by the microorganism outside the polymer material to the surface of the polymer material, I am angry. Due to the low molecular weight of the polymer substance, the material is collapsed and the product is decomposed by the enzymatic decomposition into a low molecular weight decomposition product of the monomer or dimer. The process in which the main chain of the polymer is cleaved by the microbial extracellular degrading enzyme to become low molecular weight is referred to as a primary degradation process. Small molecule units or dimers degraded by enzymatic digestion are absorbed into the body of microorganisms and used to synthesize various biopolymers through various metabolic pathways or used for energy production to produce carbon dioxide (aerobic environment) Methane (anaerobic environment). This process is called ultimate degradation process.

The most important property required as a biodegradable polymer material is that decomposition products should not generate harmful substances in the natural environment. Biodegradable polymers used in the development of biodegradable packaging materials include natural polymers derived from plants and animals, polymers produced by microorganisms, and some synthetic polymers.

The mulching film of the present invention means a film used for covering the soil, which is used for elevating the temperature, stabilizing the temperature, maintaining the soil moisture, preventing soil loss, suppressing the occurrence of weeds, and suppressing aphid flysch.

In one embodiment of the present invention, the present invention provides a biodegradable polymer having a degree of polymerization of 1500 to 2000, a degree of saponification of 95 to 99.8% and a number average molecular weight of 50,000 to 80,000; Plasticizers; A crosslinking agent; Cellulose based resin; And a mucilage film comprising a physiologically active substance having a sterilizing and insecticidal effect. Because it contains biodegradable polymer, it can be decomposed by more than 90% within one year after it is buried in the soil, thus preventing environmental pollution problem and no separate collection process is required. The biodegradable polymer preferably has a degree of polymerization of 1650 to 1750, a degree of saponification of 97 to 99.5% and a number average molecular weight of 70,000 to 77,000. When the biodegradable polymer has a biodegradable polymer having a degree of polymerization of less than 1,500 and a degree of saponification of less than 95% in accordance with the physical strength of the film depending on the degree of polymerization and degree of saponification of the biodegradable polymer, The strength and elongation are low and it is difficult to use as a mulching film. When the biodegradable polymer has a degree of polymerization of more than 2,000 and contains a fully-saponified biodegradable polymer, the tensile strength is increased but the elongation percentage is lowered.

In one embodiment of the present invention, the mulching film of the present invention comprises 10 to 20% by weight of a biodegradable polymer; 5 to 20% by weight of a plasticizer; 1 to 20% by weight of a crosslinking agent; 5 to 50% by weight of a cellulose resin, 0.1 to 1% by weight of phosphoric acid and 10 to 30% by weight of a physiologically active substance. When the biodegradable polymer is contained in an amount of less than 10% by weight, it is difficult to control the thickness of the film because the viscosity of the film is too low to produce a film having a low tensile strength. When the biodegradable polymer is contained in an amount exceeding 20% by weight, There is a problem that the viscosity is too high and the production of the solution is not easy. When the plasticizer is contained in an amount of less than 5% by weight, molding of the film is not easy. If the plasticizer is used in an amount exceeding 20% by weight, there is a problem in that the cost advantage is not large. When the crosslinking agent is contained in an amount of less than 1% by weight, the crosslinking reaction does not easily occur and the production of the film is not easy. If the crosslinking agent is contained in an amount exceeding 20% by weight, The cellulose-based resin is added in an amount of 5 to 50% by weight, preferably 5 to 25% by weight, in order to facilitate the decomposition of the mulching film. When the cellulose resin is contained in an amount of less than 5% by weight, the content of the cellulose-based resin is small and the decomposition period becomes long. When the cellulose resin is contained in an amount exceeding 50% by weight, the decomposition period is too short, And the biodegradation occurs.

In one embodiment of the present invention, the biodegradable polymer of the present invention is selected from starch, polycaprolactone (PCL), polylactic acid (PLA), polyvinyl alcohol (PVA), aliphatic polyesters, (PVA, polyvinyl alcohol), but it is not limited to the examples.

In one embodiment of the present invention, the physiologically active substance of the present invention is at least one selected from the group consisting of Gossam extract, Ginkgo biloba leaf extract, fig leaf extract, bug extract extract and mixtures thereof. More specifically, A mixture of gossam extract and ginkgo extract, ii) a mixture of gossypium extract and fig leaf extract, iii) a mixture of gossypium extract and insect repellent extract, iv) ) Mixture of ginkgo leaf extract and insect repellent extract, v) mixture of ginkgo leaf extract and fig leaf extract, vi) mixture of insect repellent extract and fig leaf extract, 혼합물 mixture of gossam extract, ginkgo leaf extract and insect repellent extract, ginseng extract, A mixture of extracts and fig leaf extract, ⅸ) Ginkgo biloba extract, Mixture and ⅹ leaf extract) may comprise a mixture of Sophora extract, ginkgo biloba extract, pyrethrum extract and extract of fig leaves.

In one embodiment of the present invention, the plasticizer of the present invention is any one or more selected from the group consisting of dioctyl phthalate, dioctyl adipate, tricalcium stearate, and polyethylene glycol, preferably polyethylene glycol, It is not.

Specifically, the crosslinking agent of the present invention may be selected from the group consisting of tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylene diisocyanate, ethylene glycol diglycidyl ether, triglycidyl Ether, trimethylolpropane triglycidyl ether, and glyoxal, and is preferably glyoxal, but is not limited to examples.

Specifically, the cellulose resin of the present invention is any one or more selected from the group consisting of cellulose ester, triacetylcellulose, cellulose propionate, cellulose acetate propionate, cellulose diacetate, cellulose acetate butyrate and methyl cellulose, Is methylcellulose, but is not limited to the examples.

In one embodiment of the present invention, the present invention provides a method for producing an aqueous solution, comprising: 1) mixing 10 to 20% by weight of biodegradable polymer with 5 to 25% by weight of distilled water and stirring at 80 to 85 캜 for 2.5 to 3.5 hours to prepare an aqueous solution Manufacturing steps; 2) adding 10 to 30% by weight of physiologically active substance and 5 to 50% by weight of cellulose resin to the aqueous solution of step 1) and mixing to prepare a mixed solution; 3) mixing the aqueous solution of step 2) with 5 to 20% by weight of a plasticizer and stirring at 80 to 85 ° C for 50 to 70 minutes; 4) mixing the crosslinking agent in an amount of 1 to 20% by weight and stirring at 80 to 85 ° C for 15 to 45 minutes after the step 3); 5) adding 0.1 to 1% by weight of phosphoric acid to the mixture obtained by mixing the cross-linking agent in the step 4) to adjust the pH; 6) a step of uniformly pouring the mixture obtained in the step 5) on a flat plate surface, and drying the mixture in a dryer at 50 to 70 ° C for 12 to 16 hours; 7) attaching a film comprising the biodegradable polymer of step 6) to the base film; And 8) coating a liquid raw material selected from silicon or wax on one side or both sides of the base film to which the film containing the biodegradable polymer of 7) is attached.

Specifically, the biodegradable polymer of the present invention may be at least one selected from the group consisting of starch, polycaprolactone (PCL), polylactic acid (PLA), polyvinyl alcohol (PVA), aliphatic polyesters, And is preferably polyvinyl alcohol (PVA, polyvinylalcohol), but is not limited to examples.

Specifically, the physiologically active substance is at least one selected from the group consisting of extracts of Gossam gambus, Ginkgo biloba leaf extract, fig leaf extract, and mixtures thereof. More specifically, the physiologically active substance is at least one selected from the group consisting of Gossam extract, Ginkgo biloba extract, A mixture of ginseng extract and ginseng extract, a mixture of ginseng extract and ginkgo extract, a mixture of ginseng extract and fig leaf extract, a mixture of ginseng extract and insect repellent extract, iv) a mixture of ginkgo leaf extract and insect repellent extract, v) A mixture of ginkgo extract and fig leaf extract, a mixture of ginkgo extract and fig leaf extract, a mixture of ginkgo extract, ginkgo leaf extract and ginkgo extract, a mixture of ginger extract, ginkgo leaf extract and fig leaf extract, ginkgo leaf extract , A mixture of insect repellent extract and fig leaf extract and x) gossam extract, Ginkgo leaf extract, bug extract extract and fig leaf extract.

Specifically, the step 7) is a step of attaching a film containing a biodegradable polymer to a base film. The base film is paper, preferably a thin paper, but is not limited to the examples.

In one embodiment of the present invention, the coating thickness of the liquid raw material in the step 8) of the present invention is 0.001 to 0.04 inch, preferably 0.002 to 0.02 inch, but is not limited to the examples. The liquid fuel coating material is coated using any one of roll coating, knife coating, and spray coating, and is preferably knife coating, but is not limited to the examples.

Specifically, the knife coating is a method of applying a coating resin using a knife or a blade, and the thickness of the coating is controlled by the distance between the knife and the substrate. Knife over roll is the most widely applied method and the amount of coating resin is adjusted by the interval between the roller and the knife of the lower surface. The quality of the coating depends on the angle of the knife, the shape of the knife, the web passing speed, and the flow characteristics of the resin.

The present invention relates to a mulching film having sterilization and insecticidal effect and a method for producing the mulching film, and it is easy to use compared to a conventional polyethylene mulching film by increasing the strength and elongation of the phosphorus. And it is possible to prevent pathogens originating from the soil to prevent pests and diseases. In addition, the decomposition period of the mulching film can be controlled depending on the type of the crop.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart of a method for producing a mulching film of the present invention.
Fig. 2 is a photograph showing the result of growing lettuce using a mulching film containing a physiologically active substance and a mulching film not containing the mulching film.

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood that both the foregoing description and the following detailed description are exemplary, explanatory and are intended to be illustrative, and not restrictive. The scope of the invention is defined by the appended claims rather than by the foregoing description. will be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart of a method for producing a mulching film of the present invention. 1) preparing an aqueous solution (S100), mixing 5 to 12% by weight of biodegradable polymer with 5 to 25% by weight of distilled water, stirring at 80 to 85 ° C for 2.5 to 3.5 hours to prepare an aqueous solution, , A biodegradable polymer having a degree of polymerization of 1,500 to 2,000, a degree of saponification of 95 to 99.8% and a number average molecular weight of 50,000 to 80,000 is stirred at 80 to 85 ° C for 3 hours to prepare an aqueous solution, more preferably a degree of polymerization of 1700, To 99.5, and the number average molecular weight is 75,000, and is not limited to the examples.

2) a step S200 of mixing the physiologically active substance and the cellulose resin into the aqueous solution after preparing the aqueous solution of the step 1). The physiologically active substance is contained in an amount of 10 to 30% by weight, and the cellulose-based resin is contained in an amount of 5 to 50% by weight. Specifically, the physiologically active substance is at least one selected from the group consisting of Gossam extract, Ginkgo biloba extract, fig leaf extract and mixtures thereof. More specifically, the physiologically active substance is at least one selected from the group consisting of Gossam extract, Ginkgo biloba extract, A mixture of ginseng extract and ginseng extract, a mixture of ginseng extract and ginkgo extract, a mixture of ginseng extract and fig leaf extract, a mixture of ginseng extract and insect repellent extract, iv) a mixture of ginkgo leaf extract and insect repellent extract, v) A mixture of ginkgo extract and fig leaf extract, a mixture of ginkgo extract and fig leaf extract, a mixture of ginkgo extract, ginkgo leaf extract and ginkgo extract, a mixture of ginger extract, ginkgo leaf extract and fig leaf extract, ginkgo leaf extract , A mixture of insect repellent extract and fig leaf extract and x) gossam extract, Ginkgo leaf extract, bug extract extract and fig leaf extract.

The cellulose resin is at least one selected from the group consisting of cellulose ester, triacetyl cellulose, cellulose propionate, cellulose acetate propionate, cellulose diacetate, cellulose acetate butyrate and methyl cellulose, preferably methyl cellulose , But are not limited to examples.

Mixing the physiologically active substance, and 3) mixing and stirring the plasticizer (S300). 5 to 20% by weight of a plasticizer are mixed, stirred at 80 to 85 ° C for 50 to 70 minutes, and stirred at 80 to 85 ° C for 1 hour. Then, 4) the cross-linking agent is mixed and stirred (S400). The crosslinking agent is mixed in an amount of 1 to 20% by weight, stirred at 80 to 85 ° C for 15 to 45 minutes, preferably at 80 to 85 ° C for 30 minutes. The pH is adjusted by mixing 5) phosphoric acid to the mixture obtained by mixing and stirring the cross-linking agent (S500). Phosphoric acid is added to adjust the pH to an acidic state of 2 to 3. Thereafter, the mixture in an acidic state is uniformly poured into a uniform plate, and then dried in a dryer at 50 to 70 ° C for 12 to 16 hours (S600), preferably at a dryer at 60 ° C for about 12 hours. And a drying step (S600), a film containing the biodegradable polymer is prepared, and the film is attached to the base film (S700). After the film including the biodegradable polymer is attached to the base film, the liquid raw material is coated (S800), and the coating is applied to the base film by any one of roll coating, knife coating, and spray coating Coating is carried out using one coating method, preferably coating using a knife coating method, and the coating thickness of the liquid raw material is 0.001 to 0.04 inch, preferably 0.002 to 0.02 inch.

[Production Example 1]

Manufacture of mulching film

(PVA) having a neutralization degree of 1700, a degree of saponification of 98 to 99.5% and an average molecular weight of 75,000 were mixed with 24% by weight of distilled water and stirred at 80 to 85 ° C for 2 hours to prepare a PVA aqueous solution do.

100 g of powdered red ginseng was mixed with 1 L of distilled water, heated at 70 to 80 ° C. for 1 to 2 hours, filtered, and concentrated using a rotary vacuum evaporator to obtain 10 g of concentrated gossam extract and 25 g of methyl cellulose And mixed in the aqueous PVA solution.

Then, 15 wt% of polyethylene glycol was added as a plasticizer, and the mixture was stirred at 80 to 85 ° C for 60 minutes. Thereafter, 10 wt% of glyoxal was mixed as a crosslinking agent, and the mixture was stirred at 80 to 85 ° C for about 30 minutes. To the stirred solution, 1% by weight of phosphoric acid is added to adjust the pH to 2 to 3. The mixed mixture is poured so that the surface is evenly distributed on a flat plate, dried in a drier at 60 ° C for 12 hours, and separated from the plate. Thereafter, the separated polymer film is attached to the thin paper.

Wax is coated on one surface of a thin paper having a polymer film attached thereto with a thickness of 0.01 inch by using a knife coating apparatus which can be continuously moved by passing between a guide roll and a back-up.

[Production Example 2]

Except that 5% by weight of methyl cellulose was added.

[Production Example 3]

Except that 50% by weight of methyl cellulose was added.

[Production Example 4]

The extract was prepared in the same manner as in Preparation Example 1, except that Ginkgo biloba extract was used instead of Ginkgo extract.

[Production Example 5]

Was prepared in the same manner as in Preparation Example 1, except that the fig leaf extract was used instead of the gosam extract.

[Production Example 6]

The extract was prepared in the same manner as in Preparation Example 1, except that the extract of Gossam ginseng, Ginkgo biloba extract and fig leaf extract were mixed at a ratio of 1: 1: 1 instead of Gossam extract.

[Comparative Example 1]

The extract was prepared in the same manner as in Preparation Example 1, except that the extract was not included.

[Comparative Example 2]

Was prepared in the same manner as in Preparation Example 1, except that it did not contain methyl cellulose.

[Comparative Example 3]

The procedure of Preparation Example 1 was repeated except that cellulose resin was used instead of methyl cellulose.

[Example 1]

Identification of insecticidal effect of extract

Ginger extract, ginkgo leaf extract, fig leaf extract and mixtures thereof.

The leaf disk method was used for Tetranichus, Myzus persicae, Spodoptera litura, and Plutella xylostella. The leaf disc method was used for the toxicity test of the spider mite, The salting effect of female adults was determined by cutting the kidney beans into 2 × 2 cm and placing them on a chalet covered with water. The female adults were inoculated with 30 mites of the spotted mites and then fixed for 30 minutes. The extracts were hand sprayed at a distance of 25 cm from the chalet Sprinkled for 5 seconds and then shaded. The treated chalks were examined at 24 and 72 hours after storage at room temperature.

The lysimetric discrimination was considered to be dead when a human body was contacted with the tip of a brush under a dissecting microscope to not move the body length.

Extraction with distilled water is performed by grinding ginseng, ginkgo leaf or fig leaves with a mixer and extracting the mixture by boiling in water at 80 ° C for 2 hours. The methanol extract means an extract extracted with methanol.

Gosam extract Ginkgo biloba extract Fig leaf extract 1: 1: 1 mixture Distilled water extraction Methanol extraction Distilled water extraction Methanol extraction Distilled water extraction Methanol extraction Distilled water extraction Methanol extraction 24 hours 48.4% 50% 47.2% 51.2% 45.6% 53% 56% 62% 72 hours 77.6% 79.3% 71.2% 76% 72.2% 75% 84.3% 88.4%

Table 1 shows the results of measuring the insecticidal effect of the extracts obtained by extracting ginseng, ginkgo leaf and fig leaves using distilled water and methanol. After 24 hours, the insecticidal rates were 40% and 70%, respectively, after 72 hours.

In addition, it was confirmed that the mixture of each extract showed a killing rate of about 10% higher than that of each extract alone.

[Example 2]

Identification of insecticidal effect of mulching film containing extract

The lettuce was cultivated and the insecticidal effect was confirmed by the final yield of the harvester depending on whether the mulching film contained the physiologically active substance.

The specific cultivation conditions of lettuce are as follows.

planter
(Month, day) Graft
(Month, day) Planting density
(cm) harvest Remarks 6.5 6.27 30 x 14 Mid-August It conforms to RDA standards.

As a result of the investigation, the growth and yield of the lettuce were checked. The results are shown in Table 3 and FIG.

30 days after growth 50 days after growth Length (cm) Number of leaves () Length (cm) Number of leaves () Production Example 1 13 8.5 15.5 12 Production Example 4 13.5 8.5 15 12.5 Production Example 5 13 8.5 15 12.5 Production Example 6 14 9 16.5 15.5 Comparative Example 1 12.5 8 14 11

As shown in Table 3 and FIG. 2, it was confirmed that the growth of lettuce was superior to that of the mulching film when compared with the case of not including ginseng extract, ginkgo leaf extract and fig leaf extract.

This inhibited soil pathogens and positively influenced the growth of lettuce, because it contained gossam extract, ginkgo leaf extract, fig leaf extract or a mixture thereof. The extracts of gossam extract, ginkgo leaf extract, fig leaf extract or In the case of Comparative Example 1 which does not contain the mixture of these, the growth of lettuce was less than that of the production example due to the pathogenic bacteria in the soil.

[Example 3]

Evaluation of properties of mulching film

(1) Property evaluation of mulching film

The physical properties of Production Examples 1 to 3 and Comparative Example 3 were evaluated, and the results are shown in Tables 4 and 5 below.

To evaluate the physical properties, a universal material testing machine (INSTRON 5565, 500kgf, USA) and a thickness measuring instrument (2109-F, 5mm, Mitutoyo, JAPAN) were used. After the sample was exposed for about 6 hours at 23 ° C and 50% RH, The test specimen was punched and tested at a test speed of 500 mm / min.

Production Example 1 Production Example 2 Production Example 3 Tensile Strength (MPa) 2793 4920 4615 Elongation (%) 103 207 93 Tear strength (N / cm) 1089 1698 1335 Thickness (mm) 0.046 0.046 0.044

Low density Linear low density The tensile strength Elongation Phosphorus strength The tensile strength Elongation Phosphorus strength Production Example 1 ◎ ○ ◎ ◎ ○ ◎ Production Example 2 ◎ ○ ◎ ◎ ○ ◎ Production Example 3 ◎ △ ◎ ◎ △ ◎ Comparative Example 3 △ △ △ △ △ △

(&Amp; cir &: superior, O: identical, &

Table 4 shows the average values of the tensile strength, elongation, tear strength and thickness of the mulching films produced by Production Examples 1 to 3.

Table 5 shows the results of comparing KS standard values of conventional low density polyethylene film for agricultural use and linear low density polyethylene film for agricultural use and physical property values of mulching films of Production Examples 1 to 3 and Comparative Example 3.

According to Table 5, it was confirmed that the tensile strength and the tear strength were higher than those of conventional low density polyethylene films (tensile strength: 1.4 to 3 times, tear strength: 1.4 to 2.5 times). However, in the elongation ratios, Production Examples 1 and 2 showed the same values, but Production Example 3 was found to be 0.3 to 0.8 times less. On the other hand, in the case of Comparative Example 3 containing cellulose, it was confirmed that it was 0.5 to 2 times less than the KS standard, and thus the physical properties are lower than those of the production example.

(2) Property evaluation after mulching of mulching film

Mulching films of Production Examples 1 to 3 and Comparative Example 3 were laid on the land to evaluate their physical properties under the influence of sunlight, rainfall and soil in a natural state.

The equipment used was a universal material testing machine (INSTRON 5565, 500 kgf, USA).

KS standard (low density polyethylene) 10 days 20 days 30 days 45 days Tensile load (N): Based on the thickness of 0.05 mm 8
.35 Production Example 1 ◎ ◎ ◎ ◎ Production Example 2 ◎ ◎ ◎ ◎ Production Example 3 ◎ ○ △ △ Production Example 4 △ △ △ △

(&Amp; cir &: superior, O: identical, &

According to Table 6, Production Examples 1 and 2 were 1.4 to 2 times more than KS standard (low density polyethylene film) even after 45 days from mulching, and Production Example 3 showed KS It was confirmed that the amount of the test sample was 0.3 to 0.5 times lower than the standard.

On the other hand, in the case of Comparative Example 3 containing cellulose, it was confirmed that it was 0.8 to 1.5 times lower than the KS standard.

[Example 4]

Evaluation of biodegradability of mulching film

In order to confirm the biodegradability of the mulching films of Production Examples 1 to 3, Comparative Examples 2 and 3 under aerobic composting conditions, KS M 3100-1: 2003 was applied to measure the amount of carbon dioxide generated in the aerobic composting condition Respectively.

ThCO2 (g-CO2 / ves.) Biodegradability (%) Production Example 1 2.0557 54.4 Production Example 2 2.4967 30.0 Production Example 3 1.2998 74.9 Comparative Example 2 9.1462 5.3 Comparative Example 3 8.3976 30.4

According to Table 7, it was confirmed that in Comparative Example 2, biodegradation hardly occurs.

On the other hand, in the case of Production Examples 1 to 3 and Comparative Example 3, biodegradation can be confirmed.

As a result, when the biodegradable polymer contains a cellulose-based resin, biodegradation can be smoothly performed. However, when a cellulose resin is included, there is no problem in biodegradation, but it can be confirmed that there is a problem that the mechanical properties are poor. Thus, when methyl cellulose is used to solve such a problem, a mulching film having biodegradability and excellent mechanical properties can be produced. Also, it was confirmed that the biodegradation period can be controlled according to the content of methyl cellulose.

Claims (6)

A biodegradable polymer having a degree of polymerization of 1500 to 2000, a degree of saponification of 95 to 99.8% and a number average molecular weight of 50,000 to 80,000;
Plasticizers;
A crosslinking agent;
Phosphoric acid;
Cellulose based resin; And
A physiologically active substance having a sterilizing and insecticidal effect,
The physiologically active substance is a mixture of ginseng extract, ginkgo leaf extract and fig leaf extract,
Wherein the plasticizer is at least one selected from the group consisting of dioctyl phthalate, dioctyl adipate, tricalcium stearate, and polyethylene glycol,
The crosslinking agent is selected from the group consisting of tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylylene diisocyanate, ethylene glycol diglycidyl ether, triglycidyl ether, Triglycidyl ether, and glyoxal, and at least one selected from the group consisting of
Wherein the cellulose resin is at least one selected from the group consisting of cellulose ester, triacetylcellulose, cellulose propionate, cellulose acetate propionate, cellulose diacetate, cellulose acetate butyrate and methyl cellulose,
Wherein a liquid raw material selected from silicone or wax is coated on one surface or both surfaces,
Mulching film. The method according to claim 1,
The mulching film comprises
10 to 20% by weight of a biodegradable polymer; 5 to 20% by weight of a plasticizer; 1 to 20% by weight of a crosslinking agent; 5 to 50% by weight of a cellulose resin, 0.1 to 1% by weight of phosphoric acid and 10 to 30% by weight of a physiologically active substance,
Mulching film. The method according to claim 1,
The biodegradable polymer may contain,
Wherein the polymer is at least one selected from the group consisting of starch, polycaprolactone (PCL), polylactic acid (PLA), polyvinyl alcohol (PVA), aliphatic polyesters,
Mulching film. 1) preparing an aqueous solution by mixing 10 to 20% by weight of biodegradable polymer with 5 to 25% by weight of distilled water and stirring at 80 to 85 ° C for 2.5 to 3.5 hours to prepare an aqueous solution;
2) adding 10 to 30% by weight of physiologically active substance and 5 to 50% by weight of cellulose resin to the aqueous solution of step 1) and mixing to prepare a mixed solution;
3) mixing 5 to 20% by weight of a plasticizer in the mixture of step 2) and stirring at 80 to 85 ° C for 50 to 70 minutes;
4) mixing the crosslinking agent in an amount of 1 to 20% by weight with stirring at 80 to 85 ° C for 15 to 45 minutes after the stirring in the step 3);
5) adding 0.1 to 1% by weight of phosphoric acid to the mixture obtained by mixing the cross-linking agent in the step 4) to adjust the pH;
6) a step of uniformly pouring the mixture obtained in the step 5) on a flat plate surface, and drying the mixture in a dryer at 50 to 70 ° C for 12 to 16 hours;
7) attaching a film comprising the biodegradable polymer of step 6) to the base film; And
8) coating a selected liquid raw material, such as silicon or wax, on one or both sides of the base film with the film containing the biodegradable polymer of step 7)
The physiologically active substance is a mixture of ginseng extract, ginkgo leaf extract and fig leaf extract,
Wherein the plasticizer is at least one selected from the group consisting of dioctyl phthalate, dioctyl adipate, tricalcium stearate, and polyethylene glycol,
The crosslinking agent is selected from the group consisting of tolylene diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isoboron diisocyanate, tetramethylxylylene diisocyanate, ethylene glycol diglycidyl ether, triglycidyl ether, Triglycidyl ether, and glyoxal, and at least one selected from the group consisting of
Wherein the cellulose resin is at least one selected from the group consisting of cellulose ester, triacetyl cellulose, cellulose propionate, cellulose acetate propionate, cellulose diacetate, cellulose acetate butyrate and methyl cellulose,
A method for producing a mulching film. 5. The method of claim 4,
The biodegradable polymer may contain,
Wherein the polymer is at least one selected from the group consisting of starch, polycaprolactone (PCL), polylactic acid (PLA), polyvinyl alcohol (PVA), aliphatic polyesters,
A method for producing a mulching film. 5. The method of claim 4,
The coating thickness of the liquid raw material in the step 8)
0.001 to 0.04 inches,
A coating method using any one of a roll coating method, a knife coating method, and a spray coating method,
A method for producing a mulching film.

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