KR20240039716A - Manufacturing method of Resin for biodegradable agricultural mulching vinyl which contains essential fertilizer. - Google Patents

Abstract

We manufacture resin for agricultural mulching vinyl that is highly biodegradable, has a weed-suppressing function, and can consistently provide basic plant nutrients. It is an eco-friendly chemical composed of biodegradable polymer, water-soluble polymer, oxidized starch, microbial activity, and metal salt. It is a method of manufacturing resin for biodegradable agricultural mulching vinyl containing fertilizer ingredients that prevent acidification of the soil through use, have a weed-suppressing effect when plants grow, and can maintain healthy plant growth through continuous supply of nutrients.
It is characterized by consisting of a pulverizing step of pulverizing the drug, a mixing step of mixing the pulverized drug with a biodegradable material, and a resin molding step of pelletizing the mixture in a resin molding machine.
In addition, the mixing ratio of the raw materials used is 50 to 100 parts by weight of polyvinyl alcohol, 100 to 200 parts by weight of oxidized starch, 5 to 20 parts by weight of xanthan gum, and 5 to 5 parts by weight of magnesium carbonate per 1,000 parts by weight of polybutylene adipate tetraphthalate (PBAT). The fertilizer ingredients are 20 parts by weight, 5 to 20 parts by weight of copper carbonate, 30 to 50 parts by weight of calcium carbonate, 30 to 50 parts by weight of potassium sulfate, 30 to 50 parts by weight of ammonium nitrate, and 30 to 50 parts by weight of sodium phosphate. We manufacture resin for manufacturing biodegradable agricultural mulching vinyl containing

Description

{Manufacturing method of Resin for biodegradable agricultural mulching vinyl which contains essential fertilizer.}

The present invention relates to a resin for producing agricultural mulching vinyl that has a rapid biodegradation rate and can consistently provide basic plant nutrients. It relates to a resin for manufacturing biodegradable agricultural mulching vinyl containing fertilizer ingredients and a weed-suppressing function that can prevent acidification and maintain healthy plant growth through continuous supply of nutrients during plant growth.

The demand for mulching vinyl, which is used for the purposes of maintaining moisture in the soil, maintaining warmth, preventing cold damage, and preventing loss of soil due to rainfall, has great advantages in suppressing weeds, reducing pesticides, and saving labor costs, but it is difficult to recycle, so most of it is illegally buried after use. The situation is that it is being burned illegally or is becoming a serious source of pollution. Of the approximately 750,000 tons used annually, the collection rate is less than 60% of the average vinyl collection rate. In particular, the black mulching vinyl left here and there in rural areas can be viewed as almost uncollected mulching vinyl.

There is an urgent need to develop eco-friendly mulching vinyl to take advantage of its advantages and solve problems during disposal.

To solve these problems, liquid mulching vinyl and eco-friendly vinyl mulching fluids have been developed, but their moisture retention function is weaker than vinyl mulching products, and in particular, they do not have a function to prevent loss of soil due to rainfall, so there are limitations in their use.

In addition, in the case of biodegradable mulching plastic, the unit cost of use is high, so it is not economically feasible for use except for high-income crops, so it is not widely distributed.

Due to these problems, mulching vinyl with general functions such as heat retention, moisture retention, cold prevention, weed suppression, and pesticide reduction is mostly used. Prior technologies for such mulching vinyl include Korea Registered Patent No. 10-2026121 “Biodegradable agricultural reflective film containing calcium fertilizer ingredients” (registration date; 2019.09.23), Korea Registered Patent No. 10-1745452 “Tensile strength There are “Improved Naturally Degradable Multing Agent” (registration date: 2017.06.02) and Republic of Korea Patent No. 10-2169864 “Eco-friendly vinyl mulching solution composition and method for manufacturing the same” (registration date: 2020.10.20). Mulching Vinyl In order to solve the shortcomings of the liquid composition, water-soluble polymer is used as a film forming agent to form a polymer film on the soil after spraying to counter the effect of mulching vinyl. However, when used for outdoor crops, it has the function of preventing soil loss due to precipitation. It is weak and vulnerable to moisture, making it difficult to exert a clear mulching function. In addition, because the polymer film layer goes down to the bottom of the soil over time, it has the disadvantage of slowing down root growth and causing roots to grow thinner.

In addition, in the case of mulching agents coated with water-soluble PVA on natural fibers or cotton, the tensile strength is higher than that of mulching vinyl made of LDPE (Low Density Polyrthylene) resin with a thickness of 0.02 to 0.035 mm, so it is less flexible and requires a lot of attention in the production process and raw material selection. It requires steps and has the disadvantage of low productivity.

In addition, in the case of mulching vinyl with increased biodegradability, when starches are used, outdoor use is limited due to its weak physical properties and moisture, and when biodegradable additives are used, it contains the risk of microplastics generated by oxidative biodegradation, which is a problem. The use of PLA, an eco-friendly material, has the disadvantage of being economically unfeasible due to the high cost of raw materials.

Republic of Korea Registered Patent No. 10-2026121 “Biodegradable agricultural reflective film containing calcium fertilizer ingredients” (registration date; 2019.09.23) Republic of Korea Patent No. 10-1745452 “Naturally degradable multing agent with improved tensile strength” (Registration date: 2017.06.02) Republic of Korea Patent No. 10-2169864 “Eco-friendly vinyl mulching solution composition and method for manufacturing the same” (registration date: October 20, 2020).

The purpose of the present invention is to manufacture agricultural mulching vinyl that is highly biodegradable, has a weed-suppressing function, and can consistently provide basic plant nutrients. It is an eco-friendly material composed of biodegradable polymer, water-soluble polymer, oxidized starch, microbial activity, and metal salt. The purpose is to manufacture biodegradable agricultural mulching vinyl containing fertilizer ingredients that prevent soil acidification through the use of effective chemicals, have a weed-suppressing effect when plants grow, and can maintain healthy plant growth through continuous supply of nutrients.

In order to achieve the above purpose, it is characterized by consisting of a pulverizing step of selectively pulverizing the drug, a mixing step of mixing the pulverized drug and the biodegradable material in the pulverizing step, and a resin molding step of pelletizing the mixture in a resin molding machine. In addition, the mixing ratio of the raw materials used is 50 to 100 parts by weight of water-soluble polymer, 100 to 200 parts by weight of oxidized starch, 5 to 20 parts by weight of xanthan gum, and 5 to 20 parts by weight of magnesium carbonate per 1,000 parts by weight of polybutylene adipate tetraphthalate (PBAT). Parts by weight, 5 to 20 parts by weight of copper carbonate, 30 to 50 parts by weight of calcium carbonate, 30 to 50 parts by weight of potassium sulfate, 30 to 50 parts by weight of ammonium nitrate, 30 to 50 parts by weight of sodium phosphate, and containing fertilizer ingredients. We manufacture resin for manufacturing biodegradable agricultural mulching vinyl.

The biodegradable mulching vinyl of the present invention oxidizes and decomposes metal salts into small molecular chains of 4,000 to 10,000 or less in the soil when landfilling, and oxidizes starch to promote the erosion-digestion-conversion process by microorganisms. and food additives are used to increase biodegradability by microorganisms, so the biodegradation rate is fast, and by adding inorganic substances containing essential ingredients for plant growth, the rooting and growth of plants are maintained healthy, and the unit cost of the raw materials used is low. It is possible to economically manufacture multi-functional, eco-friendly mulching vinyl.

Figure 1 is a process flow chart of a method for manufacturing biodegradable agricultural mulching vinyl containing fertilizer ingredients.

The manufacturing method of the mulching vinyl of the present invention will be described in detail with reference to the attached drawings.

As shown in Figure 1, the method for producing biodegradable agricultural mulching vinyl containing fertilizer ingredients of the present invention includes a first grinding step (A10) of selectively grinding chemicals, mixing the chemicals pulverized in the first grinding step and oxidized starch. It consists of a second mixing step (A20) and a third resin molding step (A30) in which the second mixture is pelletized in a resin molding machine.

In addition, the mixing ratio of the raw materials used is 50 to 100 parts by weight of water-soluble polymer, 100 to 200 parts by weight of oxidized starch, 5 to 20 parts by weight of xanthan gum, 5 to 20 parts by weight of magnesium carbonate, and 5 to 5 to 20 parts by weight of copper carbonate per 1000 parts by weight of biodegradable resin. It consists of 20 parts by weight, 30 to 50 parts by weight of calcium carbonate, 30 to 50 parts by weight of potassium sulfate, 30 to 50 parts by weight of ammonium nitrate, and 30 to 50 parts by weight of sodium phosphate.

The process of manufacturing biodegradable agricultural mulching vinyl containing fertilizer ingredients according to the above configuration is as follows.

As shown in Figure 1, in the first grinding step (A10), water-soluble polymer, xanthan gum, calcium sulfate, ammonium nitrate, and sodium phosphate are evenly ground to a size of 150 to 200 mesh using a high-speed grinder.

The second mixing step (A20) is . Mix the first mixture with oxidized starch, magnesium carbonate, and calcium carbonate.

The third resin molding step is to mix the second mixture with a biodegradable resin, extrude the resin using a resin molding machine at 130 to 150 degrees Celsius, then pass coolant (2 to 5 degrees Celsius) for 20 to 30 seconds to quickly cool it and then use a cutting machine. Use to manufacture pelletized resin with a size of 15~17pcs/g.

Polyvinyl alcohol is used as a water-soluble polymer, and when mixed with biodegradable resin at a ratio of 10:1, it increases the moisture absorption rate (MVTR) in the air and promotes the biodegradation rate of the biodegradable resin. It has the disadvantage of deteriorating the physical properties of vinyl when used in excess of the appropriate amount. Oxidized starch promotes the erosion-digestion-conversion process of microorganisms and promotes the biodegradation process of polymers divided into small molecular units by the metal salts used. When used in less than the appropriate amount, the biodegradation rate is slow, and when used in more than the appropriate amount, the moisture permeability of mulching vinyl is high, weakening the physical properties of the vinyl. Xanthan gum is used in the microbial food chain and has the effect of improving the tensile strength of vinyl. If more than the appropriate amount is used, vinyl of uneven thickness is produced during vinyl extrusion.

Magnesium carbonate and copper carbonate have the function of rapidly progressing biodegradation by microorganisms by oxidizing and decomposing the polymer into small molecular chains with a molecular size of 4,000 to 10,000 or less. The appropriate mixing ratio of magnesium carbonate and copper carbonate is 1:1. The ratio of is the most stable. When used in less than the appropriate amount, the effect is minimal, and when used in more than the appropriate amount, it is uneconomical. Calcium carbonate promotes the oxidative decomposition of magnesium carbonate and copper carbonate.

Potassium sulfate, ammonium nitrate, and sodium phosphate are substances that provide nitrogen, phosphoric acid, and potassium, which are the basic elements of plant growth. They permeate into the soil when moisture permeates through the water permeability of vinyl and have the function of promoting plant growth. However, if used in excess of the appropriate amount, they can be excessive. Its use may have an adverse effect on plant growth.

As biodegradable resins, polyglycolic acid, polylactic acid, polyphtylene adipate tetraphthalate, polyhydroxy butyrate, etc. are used, and the present invention uses polybutylene adipate tetraphthalate (PBAT).

To measure the chemical decomposition rate, weed suppression function, and growth promotion function according to the composition ratio of the resin for mulching vinyl manufactured by the present invention.

Each sample was prepared as follows.

sample 1

First grinding step: 100 parts by weight of oxidized starch, 10 parts by weight of xanthan gum, 30 parts by weight of potassium sulfate, 30 parts by weight of ammonium nitrate, and 30 parts by weight of sodium phosphate to 1000 parts by weight of polyvinyl alcohol using a high-speed grinder to a size of 200-300 mesh. Grind thoroughly.

Second mixing step: Make a mixture by mixing 5 parts by weight of magnesium carbonate, 5 parts by weight of copper carbonate, and 30 parts by weight of calcium carbonate with the pulverized material from the first pulverizing step at a speed of 50 RPM/min for 20 minutes using a mixer. .

Third resin molding step: Using a resin molding machine, add 350 parts by weight of the mixture mixed in the second mixing step to 1,000 parts by weight of polybtylene adipate tetraphthalate, and then extrude the resin using a resin molding machine at 130 to 150 degrees Celsius. Coolant (2 to 5 degrees Celsius) is passed through for 20 to 30 seconds to rapidly cool, then a cutting machine is used to produce pelletized resin with a size of 15 to 17 pcs/g.

Fourth vinyl extrusion step: Add 200 parts by weight of the resin pellet manufactured in the third resin molding step to 1,000 parts by weight of polybtylene adipate tetraphthalate and use a vinyl extruder at 190 to 220 degrees Celsius to mulch vinyl to a thickness of 0.03 mm. Sample vinyl is manufactured by extrusion.

sample 2

First grinding step: 200 parts by weight of oxidized starch, 20 parts by weight of xanthan gum, 50 parts by weight of potassium sulfate, 50 parts by weight of ammonium nitrate, and 50 parts by weight of sodium phosphate to 1000 parts by weight of polyvinyl alcohol using a high-speed grinder to a size of 200-300 mesh. Grind thoroughly.

Second mixing step: Make a mixture by mixing 20 parts by weight of magnesium carbonate, 20 parts by weight of copper carbonate, and 50 parts by weight of calcium carbonate with the pulverized material from the first pulverizing step at a speed of 50 RPM/min for 20 minutes using a mixer. .

Third resin molding step: Using a resin molding machine, add 350 parts by weight of the mixture mixed in the second mixing step to 1,000 parts by weight of polybtylene adipate tetraphthalate, and then extrude the resin using a resin molding machine at 130 to 150 degrees Celsius. Coolant (2 to 5 degrees Celsius) is passed through for 20 to 30 seconds to rapidly cool, then a cutting machine is used to produce pelletized resin with a size of 15 to 17 pcs/g.

Fourth vinyl extrusion step: Add 200 parts by weight of the resin pellet manufactured in the third resin molding step to 1,000 parts by weight of polybtylene adipate tetraphthalate and use a vinyl extruder at 190 to 220 degrees Celsius to mulch vinyl to a thickness of 0.03 mm. Produce sample vinyl by extrusion

sample 3

First grinding step: 150 parts by weight of oxidized starch, 15 parts by weight of xanthan gum, 40 parts by weight of potassium sulfate, 40 parts by weight of ammonium nitrate, and 40 parts by weight of sodium phosphate to 1000 parts by weight of polyvinyl alcohol using a high-speed grinder to a size of 200-300 mesh. Grind thoroughly.

Second mixing step: Make a mixture by mixing 10 parts by weight of magnesium carbonate, 10 parts by weight of copper carbonate, and 40 parts by weight of calcium carbonate with the pulverized material from the first pulverizing step at a speed of 50 RPM/min for 20 minutes using a mixer. .

Third resin molding step: Using a resin molding machine, add 350 parts by weight of the mixture mixed in the second mixing step to 1,000 parts by weight of polybtylene adipate tetraphthalate, and then extrude the resin using a resin molding machine at 130 to 150 degrees Celsius. Coolant (2 to 5 degrees Celsius) is passed through for 20 to 30 seconds to rapidly cool, then a cutting machine is used to produce pelletized resin with a size of 15 to 17 pcs/g.

Fourth vinyl extrusion step: Add 200 parts by weight of the resin pellet manufactured in the third resin molding step to 1,000 parts by weight of polybtylene adipate tetraphthalate and use a vinyl extruder at 190 to 220 degrees Celsius to mulch vinyl to a thickness of 0.03 mm. Produce sample vinyl by extrusion

sample 4

First grinding step: 100 parts by weight of oxidized starch, 10 parts by weight of xanthan gum, 30 parts by weight of potassium sulfate, 30 parts by weight of ammonium nitrate, and 30 parts by weight of sodium phosphate to 1000 parts by weight of polyvinyl alcohol using a high-speed grinder to a size of 200-300 mesh. Grind thoroughly.

Second mixing step: Make a mixture by mixing 15 parts by weight of magnesium carbonate, 15 parts by weight of copper carbonate, and 30 parts by weight of calcium carbonate with the pulverized material from the first pulverizing step at a speed of 50 RPM/min for 20 minutes using a mixer. .

Third resin molding step: Using a resin molding machine, add 350 parts by weight of the mixture mixed in the second mixing step to 1,000 parts by weight of polybtylene adipate tetraphthalate, and then extrude the resin using a resin molding machine at 130 to 150 degrees Celsius. Coolant (2 to 5 degrees Celsius) is passed through for 20 to 30 seconds to rapidly cool, then a cutting machine is used to produce pelletized resin with a size of 15 to 17 pcs/g.

Fourth vinyl extrusion step: Add 200 parts by weight of the resin pellet manufactured in the third resin molding step to 1,000 parts by weight of polybtylene adipate tetraphthalate and use a vinyl extruder at 190 to 220 degrees Celsius to mulch vinyl to a thickness of 0.03 mm. Produce sample vinyl by extrusion

sample 5

First grinding step: 200 parts by weight of oxidized starch, 20 parts by weight of xanthan gum, 50 parts by weight of potassium sulfate, 50 parts by weight of ammonium nitrate, and 50 parts by weight of sodium phosphate to 1000 parts by weight of polyvinyl alcohol using a high-speed grinder to a size of 200-300 mesh. Grind thoroughly.

Second mixing step: Make a mixture by mixing 10 parts by weight of magnesium carbonate, 10 parts by weight of copper carbonate, and 50 parts by weight of calcium carbonate with the pulverized material from the first pulverizing step at a speed of 50 RPM/min for 20 minutes using a mixer. .

Third resin molding step: Using a resin molding machine, add 350 parts by weight of the mixture mixed in the second mixing step to 1,000 parts by weight of polybtylene adipate tetraphthalate, and then extrude the resin using a resin molding machine at 130 to 150 degrees Celsius. Coolant (2 to 5 degrees Celsius) is passed through for 20 to 30 seconds to rapidly cool, then a cutting machine is used to produce pelletized resin with a size of 15 to 17 pcs/g.

Fourth vinyl extrusion step: Add 200 parts by weight of the resin pellet manufactured in the third resin molding step to 1,000 parts by weight of polybtylene adipate tetraphthalate and use a vinyl extruder at 190 to 220 degrees Celsius to mulch vinyl to a thickness of 0.03 mm. Produce sample vinyl by extrusion

1) Measurement of biochemical decomposition rate

The biodegradation rate was measured by measuring the speed and conversion rate of carbon in the sample vinyl into carbon dioxide using the biodegradability test (KSM 3100-1:2003) under aerobic composting conditions.

(Experimental Chart 1)

The results in Table 3 show that samples 1 to 5 all have a biodegradation rate of over 94%.

2) Observation of weed suppression function

After sowing ginseng sprouts in a field using sample mulching plastic, we were left to stand at a temperature of 25 degrees Celsius for 30 days and observed for weed formation.

(Experiment Chart 3)

As a result of the experiment, it was observed that all samples 1 to 5 had a weed suppression function.

3) Observe growth rate

The growth rate was compared and observed after 14 days at a temperature of 25 degrees Celsius after sowing sprouts in the field using the mulching plastic of Sample 2 and the field using general mulching plastic.

(Experiment Chart 4)

As a result of the observation, it can be observed that the growth rate of the leaves and stems of hemp grown in the field using the mulching plastic of Sample 2 is better.

Claims (3)

For 1000 parts by weight of polybutylene adipate tetraphthalate, 50 to 100 parts by weight of polyvinyl alcohol, 100 to 200 parts by weight of oxidized starch, 5 to 20 parts by weight of xanthan gum, 5 to 20 parts by weight of magnesium carbonate, and 5 to 20 parts by weight of copper carbonate. 30 to 50 parts by weight of calcium carbonate, 30 to 50 parts by weight of potassium sulfate, 30 to 50 parts by weight of ammonium nitrate, and 30 to 50 parts by weight of sodium phosphate. How to manufacture. A method of manufacturing resin for manufacturing biodegradable agricultural mulching vinyl containing fertilizer ingredients, characterized by using oxidized starch and xanthan gum in a 1:1 mixing ratio to promote the microbial erosion-digestion-conversion process. A method of manufacturing resin for manufacturing biodegradable agricultural mulching vinyl containing fertilizer ingredients, characterized in that magnesium carbonate and copper carbonate are used in a ratio of 1:1 for oxidative biodegradation.