阅读说明：本技术 基于生物降解高分子材料的低co2释放量腐殖质转化方法及应用 (Low CO based on biodegradable high molecular material2Method for converting released humus and application thereof ) 是由 刘亚青 范海瑞 陈泰安 王磊 张晓鹏 向阳 于 2021-06-08 设计创作，主要内容包括：本发明属于生物降解高分子材料领域,具体是一种基于生物降解高分子材料的低CO-2释放量腐殖质转化方法及应用。使生物降解高分子材料与缓慢释放养分氮或氮和磷的材料形成复合材料体系,所述复合材料体系中的碳含量与氮含量的质量比为1-35:1。本发明材料能够促使生物降解高分子材料转化为土壤腐殖质或者堆肥腐殖质,而不是转变成温室气体CO-2排放到大气中,因此,对于节能减排以及生物降解高分子材料的绿色高效利用、生物降解高分子材料废弃物的高效绿色利用具有十分重要的意义。(The invention belongs to the field of biodegradable high polymer materials, and particularly relates to a low CO based biodegradable high polymer material 2 A method for transforming release humus and application thereof. The biodegradable high polymer material and the material which slowly releases nutrient nitrogen or nitrogen and phosphorus form a composite material system, and the mass ratio of the carbon content to the nitrogen content in the composite material system is 1-35: 1. The material can promote the biodegradable high polymer material to be converted into soil humus or compost humus instead of being converted into greenhouse gas CO 2 Is discharged into the atmosphere, thereby realizing the green and high-efficiency utilization of energy conservation and emission reduction and biodegradable high polymer materials and the biodegradation of high polymerThe efficient green utilization of the material waste has very important significance.)

1. Low CO based on biodegradable high molecular material₂The method for converting the released humus is characterized in that a composite material system is formed by a biodegradable high polymer material and a material which slowly releases nutrient nitrogen or nitrogen and phosphorus, and the mass ratio of the carbon content to the nitrogen content in the composite material system is 1-35: 1.

2. Low CO based on biodegradable polymer material according to claim 1₂The method for converting the released humus is characterized in that in the composite material system, the biodegradable high polymer material and the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus are compounded through physical blending or through hydrogen bond interaction among functional groups of all components.

3. Low CO based on biodegradable polymer material according to claim 1₂The method for converting the released humus is characterized in that the biodegradable high polymer material is a compound of one or more of a natural biodegradable high polymer material and a synthetic biodegradable high polymer material.

4. Low CO based on biodegradable polymer material according to claim 3₂The method for converting the released humus is characterized in that the natural biodegradable high polymer material is a compound of one or more of starch, cellulose, sodium alginate and chitosan, and the synthetic biodegradable high polymer material is a compound of one or more of polyvinyl alcohol, polylactic acid, polybutylene succinate and poly adipic acid/butylene terephthalate.

5. Low CO based on biodegradable polymer material according to claim 2₂The method for converting the released humus is characterized in that the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus is slow-release fertilizer, controlled-release fertilizer, polyurea, polyacrylamide, polyaspartic acid, protein and melamine copolymer resinAnd a phosphate polymer.

6. Low CO based on biodegradable polymer material according to claim 5₂The method for converting released humus is characterized in that the slow-release fertilizer comprises urea aldehyde or derivatives thereof.

7. Low CO based on biodegradable polymer material according to claim 2₂The method for converting the released humus is characterized in that the step of physically blending the biodegradable polymer material and the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus comprises the following steps: and uniformly mixing the biodegradable high polymer material with a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus, and then extruding and granulating the uniformly mixed material system through an extruder to obtain the composite material system.

8. Low CO based on biodegradable polymer material according to claim 5₂A method for converting released amount of humus, characterized in that,

the step of compounding the biodegradable high molecular material and the urea aldehyde through the hydrogen bond interaction among the functional groups of the components comprises the following steps:

(1) preparation of methylol urea powder: respectively adding calculated amounts of formaldehyde and urea into a reactor, adjusting the pH value of the system, after reacting at a set temperature, pouring a reaction solution into a beaker, sealing, freezing in a refrigerator, and then extracting and filtering out residual liquid; finally, drying the sample in a vacuum oven and then crushing the dried sample to obtain hydroxymethyl urea powder;

(2) uniformly mixing the biodegradable high polymer material with the hydroxymethyl urea powder serving as the precursor of the urea aldehyde prepared in the step (1), extruding and granulating the uniformly mixed material system through an extruder, and carrying out melt polycondensation reaction on the hydroxymethyl urea serving as the added reaction precursor of the urea aldehyde in a barrel of the extruder to obtain a composite material system formed by the interaction of the biodegradable high polymer material and the urea aldehyde through hydrogen bonds among functional groups of each component;

the step of compounding the biodegradable high molecular material and the derivative of the urea aldehyde through the hydrogen bond interaction among the functional groups of the components comprises the following steps:

preparation of methylol urea powder: respectively adding calculated amounts of formaldehyde and urea into a reactor, adjusting the pH value of the system, after reacting at a set temperature, pouring a reaction solution into a beaker, sealing, freezing in a refrigerator, and then extracting and filtering out residual liquid; finally, drying the sample in a vacuum oven and then crushing the dried sample to obtain hydroxymethyl urea powder;

and (II) uniformly mixing the biodegradable high polymer material with the precursor hydroxymethyl urea powder of the urea aldehyde prepared in the step (I) and phosphate, then extruding and granulating the uniformly mixed material system through an extruder, and carrying out melt polycondensation reaction on the added reaction precursor hydroxymethyl urea of the urea aldehyde in a barrel of the extruder to obtain a composite material system formed by the interaction of the biodegradable high polymer material and the derivative of the urea aldehyde through hydrogen bonds among functional groups of each component.

9. Low CO polymer material according to any one of claims 1 to 8 based on biodegradable polymer₂The release amount humus conversion method is applied to promoting the biodegradable high polymer material to be converted into soil humus or compost humus.

10. The use according to claim 9, wherein the biodegradable polymeric material and the material slowly releasing nutrient nitrogen or nitrogen and phosphorus form a composite material system which is added to the soil or compost raw material in a ratio of the total carbon content to the soil or compost raw material mass ratio of 1: 60-10900.

Technical Field

The invention belongs to the field of biodegradable high polymer materials, and particularly relates to a low CO based biodegradable high polymer material₂A method for transforming release humus and application thereof.

Background

Humus is a kind of macromolecular organic compound mixture commonly existing in natural environment, and is a colloidal substance formed by decomposing and converting organic matters by microorganisms. Based on the solubility of humic substances in acid and alkaline solutions, they are divided into three categories: (1) fulvic Acid (FA) which is soluble in both acid and base; (2) humic Acid (HA) which is soluble in alkali but insoluble in acid; (3) humins (HMs) that are neither acid nor alkali soluble. Humus is the main part of soil organic matter and is a specific substance of soil, and the change of the composition and the structure of the humus directly influences the property and the fertility of the soil. The humus contains various nutrient components required by the growth of crops, and can be continuously released for the crops and microorganisms to utilize along with decomposition, and simultaneously release energy required by the life activities of the microorganisms, so that the humus is closely related to the yield of the crops. In addition, humus, which is the main body constituting soil, is also an important carbon pool affecting the global carbon balance.

Biodegradable polymeric materials, as defined by the American Society for Testing and Materials (ASTM), are capable of being hydrolyzed in the presence of water or degraded by enzymes or microorganisms, whereby the polymeric backbone is broken and the relative molecular mass gradually decreases, resulting in eventual metabolism to monomers and CO₂And water. Obviously, in reducing CO₂The emission becomes the most urgent task for saving the earth and human beings, and the CO in the biodegradation process of the high polymer material is reduced₂The amount of release is of great significance.

The field of soil science considers that a part of various organic substances entering soil can be converted into soil humus, and different exogenous organic substances have different influences on the content, composition and properties of the soil humus, so that the influences on the chemical properties, aggregate composition and stability of the soil are different. On one hand, the biodegradable polymer material is pollution-free and can slowly release the contained elements, so more and more agricultural biodegradable polymer material products are developed; on the other hand, landfill is still the most commonly used method for treating polymer materials at home and abroad at present, and therefore, a large amount of waste biodegradable polymer materials after finishing the use function can inevitably enter soil, and how to convert the biodegradable polymer materials into humus more than CO₂The form of (a) is released is of particular importance.

The compost is prepared with various organic wastes, such as crop straw, weed, tree leaf, peat, organic domestic garbage, kitchen garbage, sludge, human and animal excrement, distiller's grains, fungus bran and other wastes as main material, and through controlled biochemical process of converting degradable organic matter in solid waste into stable humus with the use of microbes existing widely in nature. The organic fertilizer formed by composting and decomposition contains rich nutrient substances, has long and stable fertilizer efficiency, can promote the formation of a soil solid particle structure, and improves the capabilities of soil in water retention, heat preservation, ventilation, fertilizer preservation and the like. How to convert biodegradable high molecular materials into humus more than CO in the composting process₂Is released in the same way.

Disclosure of Invention

Against the background, the invention aims to provide a low CO based on biodegradable high polymer material₂Method for converting release amount of humus and application thereof, and promoting growth of plantsThe degradation of high molecular material into humus can reduce CO in the degradation process₂Released to allow more conversion of the biodegradable polymeric material into humus, rather than into the greenhouse gas CO, either into the soil or as compost₂And is discharged to the atmosphere.

The invention is realized by the following technical scheme: low CO based on biodegradable high molecular material₂The method for converting the released humus enables a biodegradable high polymer material and a material slowly releasing nutrient nitrogen or nitrogen and phosphorus to form a composite material system, and the mass ratio of the carbon content to the nitrogen content in the composite material system is 1-35: 1.

As a further improvement of the technical scheme of the invention, in the composite material system, the biodegradable high polymer material and the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus are compounded through physical blending or through hydrogen bond interaction among functional groups of each component.

As a further improvement of the technical scheme of the invention, the biodegradable high polymer material is a compound of one or more of a natural biodegradable high polymer material and a synthetic biodegradable high polymer material.

As a further improvement of the technical scheme of the invention, the natural biodegradable high polymer material is a compound of one or more of starch, cellulose, sodium alginate and chitosan, and the synthetic biodegradable high polymer material is a compound of one or more of polyvinyl alcohol (PVA), polylactic acid (PLA), polybutylene succinate (PBS) and polybutylene adipate/terephthalate (PBAT).

As a further improvement of the technical scheme of the invention, the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus is one or a compound of a slow release fertilizer, a controlled release fertilizer, polyurea, polyacrylamide, polyaspartic acid, protein, melamine copolymer resin and phosphate polymer.

As a further improvement of the technical scheme of the invention, the slow release fertilizer comprises urea aldehyde or derivatives thereof.

The invention also provides a preparation method of the urea aldehyde, which comprises the following steps: respectively adding calculated amounts of formaldehyde and urea into a reactor, adjusting the pH value of the system, and reacting at a set temperature; then the temperature and pH of the reactor were adjusted to continue the reaction until the system was viscous. Drying the obtained viscous product at a set temperature, and then crushing to obtain urea-formaldehyde powder.

The invention further provides a preparation method of the urea aldehyde derivative, which comprises the following steps: respectively adding calculated amounts of formaldehyde and urea into a reactor, adjusting the pH value of the system, and reacting at a set temperature; and then adjusting the temperature of the reactor, adding a calculated amount of phosphate after the temperature is raised to the set temperature, and continuing to react until the system is viscous. Drying the obtained sticky product at a set temperature, and then crushing to obtain urea aldehyde derivative powder. The phosphate is one or more of hydroxyapatite, ammonium dihydrogen phosphate, calcium superphosphate and potassium dihydrogen phosphate.

As a further improvement of the technical scheme of the invention, the step of physically blending the biodegradable polymer material and the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus comprises the following steps: and uniformly mixing the biodegradable high polymer material with a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus, and then extruding and granulating the uniformly mixed material system through an extruder to obtain the composite material system.

As a further improvement of the technical scheme of the invention, the step of compounding the biodegradable high polymer material and the urea aldehyde through the hydrogen bond interaction among the functional groups of the components comprises the following steps:

(1) preparation of methylol urea powder: respectively adding calculated amounts of formaldehyde and urea into a reactor, adjusting the pH value of the system, after reacting at a set temperature, pouring a reaction solution into a beaker, sealing, freezing in a refrigerator, and then extracting and filtering out residual liquid; finally, drying the sample in a vacuum oven and then crushing the dried sample to obtain hydroxymethyl urea powder;

(2) uniformly mixing the biodegradable high polymer material with the hydroxymethyl urea powder serving as the precursor of the urea aldehyde prepared in the step (1), extruding and granulating the uniformly mixed material system through an extruder, and carrying out melt polycondensation reaction on the hydroxymethyl urea serving as the added reaction precursor of the urea aldehyde in a barrel of the extruder to obtain a composite material system formed by the interaction of the biodegradable high polymer material and the urea aldehyde through hydrogen bonds among functional groups of each component;

the step of compounding the biodegradable high molecular material and the derivative of the urea aldehyde through the hydrogen bond interaction among the functional groups of the components comprises the following steps:

preparation of methylol urea powder: respectively adding calculated amounts of formaldehyde and urea into a reactor, adjusting the pH value of the system, after reacting at a set temperature, pouring a reaction solution into a beaker, sealing, freezing in a refrigerator, and then extracting and filtering out residual liquid; finally, drying the sample in a vacuum oven and then crushing the dried sample to obtain hydroxymethyl urea powder;

and (II) uniformly mixing the biodegradable high polymer material with the precursor hydroxymethyl urea powder of the urea aldehyde prepared in the step (I) and phosphate, then extruding and granulating the uniformly mixed material system through an extruder, and carrying out melt polycondensation reaction on the added reaction precursor hydroxymethyl urea of the urea aldehyde in a barrel of the extruder to obtain a composite material system formed by the interaction of the biodegradable high polymer material and the derivative of the urea aldehyde through hydrogen bonds among functional groups of each component.

The invention further provides the low CO based on the biodegradable high molecular material₂The release amount humus conversion method is applied to promoting the biodegradable high polymer material to be converted into soil humus or compost humus.

As a further improvement of the application technical scheme of the invention, the biodegradable polymer material and the material which slowly releases nutrient nitrogen or nitrogen and phosphorus form a composite material system, and the composite material system is added into soil or compost according to the mass ratio of the total carbon content to the soil or compost of 1: 60-10900.

In specific implementation, according to different requirements, a person skilled in the art can process the biodegradable polymer material and a material slowly releasing nutrient nitrogen or nitrogen and phosphorus into products in various shapes, including particles, sheets, film materials, pipes and the like, through a composite material system formed by simple physical blending or through hydrogen bond interaction among functional groups of each component by processes of plastic uptake, injection molding, blow molding, film blowing, casting, spinning and the like.

The technical scheme of the invention has the advantages that: the method of the invention can promote the biodegradable high molecular material to be converted into soil humus or compost humus instead of being converted into greenhouse gas CO₂The waste water is discharged into the atmosphere, so that the waste water has important significance for energy conservation and emission reduction, green and efficient utilization of biodegradable high polymer materials and efficient green utilization of biodegradable high polymer material wastes.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 shows UF, PVA and [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1FTIR spectrum of (1). It can be seen that the addition of UF results in a decrease in the intensity of the peak corresponding to the PVA functional group, with higher amounts of UF added resulting in lower peak intensities. 1622cm in the figure^-1The absorption peak of UF molecular carbonyl stretching vibration (amide I band) is shown. Comparison with the spectrum of UF revealed that [ PVA/UF]The band spectrum peak wave number of the system amide I has a certain degree of blue shift, which shows that UF generated in situ in an extruder by MU and PVA macromolecular chains form strong hydrogen bonding effect. And [ PVA + UF ]]The expansion vibration peak of the amide I band of the system does not move, which shows that no obvious interaction exists between PVA and UF molecular chains. The FTIR spectrum indicated that the product had the structure.

FIG. 2 shows UF, PVA, and [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1TG and DTG spectrum of (a). It can be seen that [ PVA/UF ]]_C:N＝5:1Thermal decomposition temperature (T)_5％) Slightly lower than [ PVA + UF ]]_C:N＝5:1That in the PVA/UF system, molecular scale mixing is formed due to PVA and UFThe intermolecular hydrogen bonds of both components are thus significantly destroyed, resulting in a thermal decomposition temperature (T) of the composite system_5％) The reduction is even more. And [ PVA/UF ]]_C:N＝15:1In contrast, [ PVA/UF ]]_C:N＝5:1Thermal decomposition temperature (T)_5％) The more the decrease, the more the UF is added, the more the intermolecular hydrogen bond destruction of the PVA component in the system is obvious, and the worse the thermal stability of the composite system is. TG and DTG spectra indicate that the product has the structure.

FIG. 3 shows PVA and [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1DSC spectrum of (1). It can be seen that [ PVA + UF ] is comparable to pure PVA]Systems and [ PVA/UF]The addition of UF in the system reduces the melting temperature of the PVA component, which shows that the introduction of UF component destroys the original strong hydrogen bond function between PVA molecular chains, further reduces the crystallinity of the PVA component, and finally causes the reduction of the melting temperature of the PVA. And [ PVA + UF ]]Comparison of the systems, [ PVA/UF]The melting temperature of the component PVA in the system is reduced more obviously, which shows that the physical mixed system [ PVA + UF ]]In the method, hydrogen bonding is formed between molecular chains of only the surface layer of each component, and the PVA/UF is in a chemical bonding system]In the method, because UF and PVA are mixed in a molecular scale, more UF molecular chains penetrate into the crystallization area of the PVA and form hydrogen bonding effect with the crystallization area of the PVA, so that the reduction of the crystallinity of the PVA is more remarkable. The DSC plot shows that the product has the structure.

FIG. 4 shows UF, PBS, [ PBS + UF]_C:N＝5.37:1And [ PBS/UF ]]_C:N＝5.37:1FTIR spectrum of (1). Can be seen to react with [ PBS/UF ]]_C:N＝5.37:1In contrast, [ PBS + UF ] obtained by direct extrusion of PBS and UF]_C:N＝5.37:1At 1622cm^-1The peak at (a) was much less blue-shifted than UF, indicating that the PBS component of the system did not interact significantly with the UF molecular chain. The IR spectrum indicated that the product had the structure.

FIG. 5 shows UF, PBS, [ PBS + UF_{]C:N＝5.37:1}And [ PBS/UF ]]_C:N＝5.37:1TG and DTG spectrum of (a). It can be seen that [ PBS/UF ]]_C:N＝5.37:1Decomposition temperature (T)_5％) Slightly lower than [ PBS + UF ]]_C:N＝5.37:1In (1). The reason is that [ PBS/UF ] obtained by reactive extrusion is comparable to simple physical mixing systems]The chain segments of the two components obtain the mixing of molecular chain segment scale, more UF molecular chains penetrate into the crystal region of PBS and form hydrogen bonding effect with the crystal region, so that intermolecular hydrogen bonds in the PBS and UF components are more damaged, and the PBS/UF]_C:N＝5.37:1Thermal decomposition temperature (T)_5％) And lower. TG and DTG spectra indicate that the product has the structure.

FIG. 6 shows the change in the content of Fulvic Acid (FA) in soil or compost during soil cultivation, potting experiments and composting. FIGS. 6A and 6B show that the FA content of all the composite systems of biodegradable polymer material and material slowly releasing nutrient nitrogen shows the tendency of rising first and then stabilizing (or slightly decreasing) during the soil cultivation and composting process, [ PVA/UF [ ]]The growth of the system was most pronounced. In contrast to PVA treatment, [ PVA + UF]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The FA content of the treated soil is respectively increased by 3.08-13.19%, 5.06-21.96% and 9.78-26.43%; and with [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The FA content of the compost as the raw material is respectively improved by 5.72 to 7.02 percent, 11.12 to 13.42 percent and 15.63 to 17.98 percent compared with that of the compost treated by PVA. As can be seen from FIG. 6C, [ PBS/UF ] was compared to PBS treatment in the potting experiment]_C:N＝1.36:1And [ PBS/UF ]]_C:N＝5.37:1The FA content of the treated soil is respectively increased by 4.06-24.51% and 5.08-17.22%.

Fig. 7 is a graph showing the change in the content of Humins (HA) in soil or compost during soil culture, potting experiments, and composting. FIGS. 7A and 7B show that HA content of all the composite systems of biodegradable polymeric materials and materials slowly releasing nutrient nitrogen treated in soil culture and compost shows a rising trend, [ PVA/UF ]]The growth of the system was most pronounced. In contrast to PVA treatment, [ PVA + UF]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The HA content of the treated soil is respectively increased by 2.90-24.60%, 5.06-35.96% and 9.78-38.62% to [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The HA content of the compost used as the raw material is respectively increased by 10.25-13.27%, 21.95-24.44% and 40.80-43.26%. As can be seen from FIG. 7C, [ PBS/UF ] was compared to PBS treatment in the potting]_C:N＝1.36:1And [ PBS/UF ]]_C:N＝5.37:1The HA content of the treated soil is respectively improved by 28.73-37.80% and 12.17-26.65%.

FIG. 8 is a graph showing the change in PQ-HA/FA values in soil or compost during soil culture, potting experiments, and composting. PQ ═ HA/FA can represent the degree of humification and the quality of humus to some extent, and the higher the PQ value, the better the quality of soil or compost. FIGS. 8A and 8B show that [ PVA + UF ] is comparable to PVA treatment]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The PQ values of the treated soil were increased by 1.67-6.21%, 0-11.07% and 7.38-9.84%, respectively, to [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1PQ values of compost as a raw material were increased by 3.59-6.08%, 7.52-11.98% and 20.9-23.90%, respectively. As can be seen from FIG. 8C, [ PBS/UF ] was compared to PBS treatment in the potting experiment]_C:N＝1.36:1And [ PBS/UF ]]_C:N＝5.37:1The PQ value of the treated soil is respectively increased by 10.68-23.70% and 5.71-13.45%.

Note: CK as blank control, UF as urea aldehyde, PVA as polyvinyl alcohol, PBS as poly (butylene succinate) [ PVA + UF ]]And [ PBS + UF ]]Composite material system [ PVA/UF ] with two components simply mixed physically]And [ PBS/UF ]]Is a composite material system formed by two components through hydrogen bond interaction, [ PVA + UF]_C:N＝m:n、[PVA/UF]_C:N＝m:n、[PBS+UF]_C:N＝m:nAnd [ PBS/UF ]]_C:N＝m:nWherein C and N are the mass ratio of carbon to nitrogen.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail below. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the examples given herein without any inventive step, are within the scope of the present invention.

The specific experimental arrangement and test method of the invention:

and (3) soil culture: adding a pure biodegradable high polymer material or a composite material system of the biodegradable high polymer material and a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus into soil according to the mass ratio of carbon content to soil of 1:60, wherein most of the material (the pure biodegradable high polymer material or the composite material system) is directly and uniformly mixed with the soil according to the proportion, the rest of the material (the pure biodegradable high polymer material or the composite material system) is put into a nylon mesh bag and then buried in the soil, and the soil without the material is used as a blank Control (CK); maintaining the soil humidity at 40%, sealing, culturing in dark at 25 deg.C, and collecting the materials and soil sample (soil with or without materials) from the mesh bag at 15, 45, 105, and 165 days. Taking out the material from the mesh bag, carefully separating the material from the adhered soil, ultrasonically cleaning the material with absolute ethyl alcohol to remove impurities adhered to the surface of the material, drying the material, weighing the material, and further analyzing the material; fulvic acid and humic acid were extracted from soil samples (soil with or without material) and tested.

Compost culture: adding a pure biodegradable high molecular material or a composite material system of the biodegradable high molecular material and a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus into compost according to the mass ratio of 1:60 of carbon content to compost (composed of cow dung and corn straws according to the mass ratio of 1: 4), wherein most of the material (the pure biodegradable high molecular material or the composite material system) and the compost are directly and uniformly mixed according to the ratio, the rest of the material (the pure biodegradable high molecular material or the composite material system) is put into a nylon mesh bag and then buried in the compost, and the compost without the material is used as a blank Control (CK); keeping the humidity of the system at 40%, sealing, culturing in the dark in an incubator at a constant temperature of 58 ℃, and taking the materials and the compost (the compost with or without the materials) from the mesh bag on 30 th, 60 th, 90 th and 120 th days. Taking the material out of the mesh bag, ultrasonically cleaning the material by using absolute ethyl alcohol to remove impurities adhered to the surface of the material, drying, weighing, and further analyzing; fulvic acid and humic acid in compost (compost with or without material) were extracted and tested.

Pot experiment: applying a pure biodegradable high polymer material or a composite material system of the biodegradable high polymer material and a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus into soil according to the mass ratio of carbon content to soil of 1:10900, wherein most of the material (the pure biodegradable high polymer material or the composite material system) is directly and uniformly mixed with the soil, and the rest of the material (the pure biodegradable high polymer material or the composite material system) is put into a nylon mesh bag and then buried in the soil. After the surface soil is paved, the soil is irrigated by tap water, and then tomato seedlings are transplanted. The material was taken out of the mesh bag at day 10 (seedling stage), day 40 (flowering stage), day 70 (fruiting stage) and day 100 (maturation stage), respectively, carefully separated from the adhered soil, ultrasonically cleaned with absolute ethanol to remove impurities adhered to the surface of the material, dried, weighed, and further analyzed. Meanwhile, a five-point sampling method is adopted to collect each processed soil sample, fulvic acid and humic acid in the soil sample are extracted, and the soil sample is tested.

The extraction method of fulvic acid and humic acid comprises the following steps: 5g of air-dried soil or compost sample (particle size)<0.25mm) was added to 30mL of distilled water, shaken at 70 ℃ for 1 hour, centrifuged at 3500r/min and 40 ℃ for 15 minutes, the supernatant was filtered with filter paper into an Erlenmeyer flask, and 30mL of the prepared solution (0.1mol/L NaOH and 0.1mol/L Na) was added₄P₂O₇And pH is 13), repeating the steps of shaking, centrifuging and filtering, and filtering to obtain a solution, namely the total alkali extracted humus. Extracting humus with 0.5M H from total alkali₂SO₄Acidifying at 65 deg.C for 1.5h, and standing overnight at 25 deg.C to precipitate black floccule; filtering to obtain floccule, i.e. humic acid, and filtrate is fulvic acid; and testing and calculating by using an organic carbon analyzer to obtain the concentrations of the humic acid and the fulvic acid, and multiplying by the dilution times to obtain the content of the humic acid and the fulvic acid.

In the formula: measured value of K-organic carbon analyzer

N-dilution factor

M-soil or compost quality

Soil culture of CO₂The release amount test method comprises the following steps: uniformly mixing a pure biodegradable high polymer material or a composite material system of the biodegradable high polymer material and a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus in a culture bottle according to the mass ratio of carbon content to soil of 1:60, and taking soil without the material as a blank Control (CK); maintaining soil humidity at 40%, sealing, culturing at 25 deg.C in dark, collecting gas with atmosphere sampler on days 15, 45, 105, and 165, and measuring CO with gas chromatograph₂Concentration, calculating to obtain CO₂The mass of carbon in (c).

Compost culture of CO₂The release amount test method comprises the following steps: uniformly mixing a pure biodegradable high polymer material or a composite material system of the biodegradable high polymer material and a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus in a culture bottle according to the mass ratio of 1:60 of carbon content to compost (consisting of cow dung and corn straws according to the mass ratio of 1: 4), and taking the compost without the material as a blank Control (CK); maintaining the humidity of the system at 40%, sealing, culturing at constant temperature of 58 deg.C in dark, collecting gas with atmospheric sampling instrument at 30, 60, 90, and 120 days, and measuring CO with gas chromatograph₂Concentration, calculating to obtain CO₂The mass of carbon in (c).

In the formula: k-gas chromatograph measurement

500-volume of culture flask

12-molar mass of carbon

22.4-molar volume of gas

In the following examples, multiple CO emissions₂Carbon content-CO released by treatment₂Carbon amount-blank released CO₂Amount of carbon

Increased humus carbon amount-original soil humus carbon amount

The amount of carbon released by biodegradation includes the much released CO₂Carbon amount and increased humus carbon amount

In the invention, the treatment refers to adding a pure biodegradable high molecular material or a composite material system of the biodegradable high molecular material and a material for slowly releasing nutrient nitrogen or nitrogen and phosphorus into soil or compost, blank or original refers to soil or compost without any material, and the carbon released by biodegradation is the carbon released by degradation of the pure biodegradable high molecular material or the composite material system of the biodegradable high molecular material and the material for slowly releasing nutrient nitrogen or nitrogen and phosphorus.

Example 1

Uniformly mixing the PVA of the biodegradable high polymer material and the urea-formaldehyde UF powder according to the mass ratio of 2.91:1, extruding and granulating by an extruder to obtain a simple physical blending system (PVA + UF) of the PVA of the biodegradable high polymer material and the UF capable of slowly releasing nutrient nitrogen]_C:N＝5:1。

Mixing PVA and [ PVA + UF ]]_C:N＝5:1Respectively mixing the components according to the respective carbon content and soil mass ratio of 1:60 into the soil, wherein most of the PVA, [ PVA + UF ]]_C:N＝5:1Respectively and uniformly mixing with soil, and respectively putting the rest parts into nylon mesh bags, and then burying the nylon mesh bags in the soil (facilitating calculation of weight loss of the material); maintaining soil humidity at 40%, sealing, culturing in 25 deg.C incubator in dark at 15, 45, 105, and 165 days, [ PVA + UF ]]_C:N＝5:1The FA content of the treated soil is 1.77g/kg, 1.93g/kg, 1.88g/kg and 1.85g/kg respectively, which are respectively improved by 3.08%, 7.57%, 8.93% and 13.19% compared with the soil treated by PVA under the same conditions; [ PVA + UF]_C:N＝5:1The HA content of the treated soil is 3.98g/kg, 4.73g/kg, 5.11g/kg and 6.01g/kg respectively, which are respectively improved by 4.80 percent, 15.26 percent, 11.79 percent and 25.23 percent compared with the soil treated by PVA under the same conditions. 165 days, [ PVA + UF]_C:N＝5:1CO released by treated soil₂The carbon amount/the carbon amount released by biodegradation is 1.10 percent, which is 7.53 percent higher than that of PVA treatment under the same condition; [ PVA + UF]_C:N＝5:1The increased humus carbon/biodegradation release carbon content of the treated soil was 42.93%The treatment efficiency is 29.31 percent higher than that of PVA treatment under the same conditions; [ PVA + UF]_C:N＝5:1Treated soil increased humus carbon/CO released₂The amount of carbon was 1.10 times that of PVA treatment under the same conditions.

PVA, [ PVA + UF ]]_C:N＝5:1Respectively mixing the raw materials according to the respective carbon content and compost mass ratio of 1:60 is added into compost (composed of cow dung and corn stalks according to the mass ratio of 1: 4), wherein most of PVA and [ PVA + UF ]]_C:N＝5:1Respectively and uniformly mixing the raw materials with the compost, and respectively putting the rest parts into nylon mesh bags and then burying the nylon mesh bags in the compost; maintaining the humidity of the system at 40%, sealing, and culturing in a 58 deg.C incubator at dark place for 30 days, 60 days, 90 days, and 120 days, [ PVA + UF ]]_C:N＝5:1The FA content of the treated compost is 11.07g/kg, 12.12g/kg, 12.87g/kg and 12.98g/kg respectively, which are respectively improved by 6.43 percent, 5.87 percent, 7.04 percent and 6.77 percent compared with the compost treated by PVA under the same conditions; [ PVA + UF]_C:N＝5:1The HA content of the treated compost is respectively 38.85g/kg, 43.66g/kg, 46.87g/kg and 48.13g/kg, which are respectively 10.25 percent, 10.18 percent, 12.18 percent and 13.27 percent higher than that of the compost treated by PVA under the same conditions. At 120 days, [ PVA + UF ]]_C:N＝5:1CO released by the treated compost₂The carbon amount/carbon amount released by biodegradation is 2.49 percent, which is 2.89 percent higher than that of PVA treatment under the same condition; [ PVA + UF]_C:N＝5:1The increased humus carbon amount/carbon amount released by biodegradation of the treated compost is 236.45 percent, which is 20.61 percent higher than that of the treated compost under the same condition; [ PVA + UF]_C:N＝5:1Increased humus carbon/CO released by treated compost₂The amount of carbon was 1.17 times that of PVA treatment under the same conditions.

Example 2

Uniformly mixing reaction precursor hydroxymethyl urea (MU) powder of a biodegradable high molecular material PBS and urea aldehyde according to a mass ratio of 7:3, extruding and granulating by an extruder, carrying out melt polycondensation on added reaction precursor UF in a cylinder of the extruder to generate urea aldehyde, and obtaining a composite material system [ PBS/UF ] formed by interaction of the biodegradable high molecular material PBS and UF slowly releasing nutrient nitrogen through hydrogen bonds]_C:N＝5.37:1。

Mixing PBS and [ PBS/UF ]]_C:N＝5.37:1Applied to soil according to the respective carbon content and soil mass ratio of 1:10900, wherein most of PBS and [ PBS/UF]_C:N＝5.37:1Respectively and uniformly mixing with soil, and respectively putting the rest parts into nylon mesh bags and then burying in the soil. After the surface soil is paved, the soil is irrigated by tap water, and then tomato seedlings are transplanted. Day 10, day 40, day 70, day 100, [ PBS/UF]_C:N＝5.37:1The FA content of the treated soil is respectively 2.07g/kg, 2.23g/kg and 2.06g/kg, which is respectively 11.63 percent, 17.22 percent, 5.08 percent and 7.56 percent higher than that of the soil treated by PBS under the same condition; [ PBS/UF]_C:N＝5.37:1The HA content of the treated soil is respectively 4.73g/kg, 4.35g/kg, 4.87g/kg and 4.42g/kg, which are respectively improved by 26.64 percent, 29.55 percent, 12.17 percent and 13.71 percent compared with the soil treated by PBS under the same conditions.

Examples 3 and 4

Uniformly mixing MU powder serving as a reaction precursor of the biodegradable high-molecular PVA and the urea aldehyde according to the mass ratio of 1.70:1 to 5.72:1, extruding and granulating by an extruder to obtain a composite material system [ PVA/UF ] formed by the interaction of the biodegradable high-molecular PVA and UF slowly releasing nutrient nitrogen through hydrogen bonds]_C:N＝5:1And [ PVA/UF]_C:N＝15:1。

Mixing PVA and [ PVA/UF ]]_C:N＝5:1、[PVA/UF]_C:N＝15:1Respectively mixing the carbon content and the soil mass ratio of 1:60 into the soil, wherein the majority of the PVA, [ PVA/UF ]]_C:N＝5:1、[PVA/UF]_C:N＝15:1Mixing with soil, and burying the rest part in nylon mesh bag; maintaining soil humidity at 40%, sealing, culturing in 25 deg.C incubator at dark place for 15 days, 45 days, 105 days, and 165 days, [ PVA/UF ]]_C:N＝5:1The FA content of the treated soil is 1.81g/kg, 2.00g/kg, 1.95g/kg and 1.93g/kg respectively, which are respectively improved by 5.06 percent, 11.20 percent, 13.44 percent and 18.09 percent compared with the soil treated by PVA under the same conditions; [ PVA/UF]_C:N＝15:1The FA content of the treated soil is 1.89g/kg, 2.13g/kg, 2.11g/kg and 1.99g/kg respectively, which are respectively improved by 9.78%, 18.67%, 22.65% and 21.76% compared with the soil treated by PVA under the same conditions; [ PVA/UF]_C:N＝5:1The HA content of the treated soil is 3.91g/kg, 4.71g/kg, 5.39g/kg and 6.55g/kg respectively, which are respectively improved by 2.81%, 14.80%, 18.04% and 36.62% compared with the PVA-treated soil under the same conditions; [ PVA/UF]_C:N＝15:1The HA content of the treated soil is respectively 4.47g/kg, 5.30g/kg, 6.08g/kg and 6.69g/kg, which are respectively 17.61%, 29.17%, 33.11% and 39.32% higher than that of the soil treated by PVA under the same conditions. 165 days, [ PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1CO released by treated soil₂The amount of carbon/amount of carbon released by biodegradation of (1.13%) and (1.11%) respectively, is increased by 21.51% and 19.35% respectively compared with that of PVA treatment under the same conditions, [ PVA/UF ]]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The increased humus carbon amount/carbon amount released by biodegradation of the treated soil were 42.49% and 45.63%, respectively, which are 27.98% and 37.44% higher than those of PVA treatment under the same conditions, [ PVA/UF%]_C:N＝5:1And [ PVA/UF]_C:N＝15:1Treated soil increased humus carbon/CO released₂The amount of carbon was 1.05 and 1.15 times that of PVA treatment under the same conditions.

Mixing PVA and [ PVA/UF ]]_C:N＝5:1、[PVA/UF]_C:N＝15:1Respectively mixing the carbon content and the compost in a mass ratio of 1:60 is added into compost (composed of cow dung and corn stalks according to the mass ratio of 1: 4), wherein most of PVA and [ PVA/UF ]]_C:N＝5:1Or [ PVA/UF ]]_C:N＝15:1Directly and uniformly mixing the compost, and respectively putting the rest parts into nylon mesh bags and then burying the nylon mesh bags in the compost; maintaining the humidity of the system at 40%, sealing, and culturing in a 58 deg.C incubator at dark place for 30 days, 60 days, 90 days, and 120 days, [ PVA/UF ]]_C:N＝5:1The FA content of the treated compost is 11.79g/kg, 12.90g/kg, 13.05g/kg and 13.51g/kg respectively, which are respectively improved by 13.42%, 12.48%, 8.53% and 11.12% compared with the compost treated by PVA under the same conditions; [ PVA/UF]_C:N＝15:1The FA content of the treated compost is respectively 12.27g/kg, 13.55g/kg, 13.73g/kg and 12.05g/kg, which is respectively improved by 17.98 percent, 18.14 percent, 14.26 percent and 15.62 percent compared with the compost treated by PVA under the same conditions; [ PVA/UF]_C:N＝5:1The HA content of the treated compost was 42.97g/kg, 49.79g/kg, 50.87g/kg, 52.87g/kg, compared to the same conditions PVThe compost treated by the A is respectively lifted by 21.95 percent, 25.65 percent, 21.75 percent and 24.44 percent; [ PVA/UF]_C:N＝15:1The HA content of the treated compost is 50.29g/kg, 57.34g/kg, 58.83g/kg and 60.87g/kg, which are respectively improved by 42.72 percent, 44.70 percent, 40.80 percent and 43.26 percent compared with the compost treated by PVA under the same conditions. 120 days, [ PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1CO released by the treated compost₂The carbon amount/the amount of carbon released by biodegradation are respectively 3.37 percent and 3 percent, which are respectively 39.26 percent and 23.97 percent higher than that of PVA treatment under the same condition, [ PVA/UF ]]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The increased humus carbon amount/biodegradation released carbon amount of the treated compost are 282.92% and 353.10% respectively, which are improved by 44.31% and 80.11% respectively than that of PVA treatment under the same conditions, [ PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The treated compost has more increased humus carbon content/more released CO₂The amount of carbon was 1.04 and 1.45 times that of PVA treatment under the same conditions.

The present invention further provides a comparative data sheet of the above examples. Wherein, UF, PVA, and [ PVA + UF ] are shown in Table 1]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1Thermal stability parameter (T) at 5% weight loss on heating of all samples₅％)。

TABLE 1

Treatment of	T5％(℃)	Weight loss ratio (%)
			PVA	253.35	5.46
[PVA+UF]C:N＝5:1	221.54	5.07
			[PVA/UF]C:N＝5:1	220.10	4.74
[PVA/UF]C:N＝15:1	225.62	4.82
			UF	192.72	4.22

Table 2 shows PVA and [ PVA + UF ]]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1The melting temperature of (2).

TABLE 2

Treatment of	Melting temperature (. degree.C.)
		PVA	224.56
[PVA+UF]C:N＝5:1	197.51
		[PVA/UF]C:N＝5:1	192.25
[PVA/UF]C:N＝15:1	198.83

TABLE 3 UF, PBS, [ PBS + UF]_C:N＝5.37:1And [ PBS/UF ]]_C:N＝5.37:1Thermal stability parameter (T) at 5% weight loss on heating of all samples_5％)。

TABLE 3

Treatment of	T5％(℃)	Weight loss ratio (%)
			PBS	367.44	1.19
[PBS+UF]C:N＝5.37:1	272.61	4.15
			[PBS/UF]C:N＝5.37:1	271.45	3.12
UF	192.72	4.22

Table 4 shows the increased humus carbon/CO release from the soil at 165 days of soil culture for each material₂The amount of carbon (c).

TABLE 4

TABLE 5 increased humus carbon/CO released for compost 120 days of treatment of each material₂The amount of carbon (c).

TABLE 5

Tables 4 and 5 show that all composite systems of biodegradable polymeric materials with materials slowly releasing nutrient nitrogen increase humus carbon/CO released more in soil culture and composting₂The carbon content of the material is higher than that of the pure biodegradable high polymer material. Degraded in soil for 165 days compared to PVA, [ PVA + UF]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1Treatment of increased humus carbon/CO released₂The carbon content is respectively increased by 10.25%, 5.29% and 15.06%; degraded in compost for 120 days, [ PVA + UF]_C:N＝5:1、[PVA/UF]_C:N＝5:1And [ PVA/UF]_C:N＝15:1Treatment of increased humus carbon/CO released₂The carbon content of the catalyst is respectively increased by 17.21%, 3.63% and 45.27%.

Table 6 shows the comparison of the contents of humic acid and fulvic acid in the soil after each material is applied to the soil according to the respective carbon content and soil mass ratio of 1:10900, mixed with the soil, and transplanted with the tomato seedlings, respectively, for 100 days after the soil is treated.

TABLE 6

Material	FA(g/kg)	HA(g/kg)
			PBS	1.88	3.88
[PBS/UF]C:N＝5.37:1	2.06	4.42
			UF	1.92	4.30

As can be seen from the table, in the potting experiment, the soil fulvic acid and humic acid contents of the composite material system of the biodegradable polymer material and the material for slowly releasing nutrient nitrogen are higher than those of the pure biodegradable polymer material, and compared with PBS and UF, in 100 days of the potting experiment, [ PBS/UF]_C:N＝5.37:1The content of fulvic acid and humic acid in the treated soil is respectively improved by 9.57 percent and 7.29 percent, and 13.92 percent and 2.79 percent.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.