CN109627361B - Modified polylactic acid biological matrix capsule wall material and method for preparing bimolecular structure slow-release algae-killing microcapsule by using same - Google Patents
Modified polylactic acid biological matrix capsule wall material and method for preparing bimolecular structure slow-release algae-killing microcapsule by using same Download PDFInfo
- Publication number
- CN109627361B CN109627361B CN201811356755.XA CN201811356755A CN109627361B CN 109627361 B CN109627361 B CN 109627361B CN 201811356755 A CN201811356755 A CN 201811356755A CN 109627361 B CN109627361 B CN 109627361B
- Authority
- CN
- China
- Prior art keywords
- polylactic acid
- solution
- stirring
- modified polylactic
- drying
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N25/00—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests
- A01N25/26—Biocides, pest repellants or attractants, or plant growth regulators, characterised by their forms, or by their non-active ingredients or by their methods of application, e.g. seed treatment or sequential application; Substances for reducing the noxious effect of the active ingredients to organisms other than pests in coated particulate form
- A01N25/28—Microcapsules or nanocapsules
-
- A—HUMAN NECESSITIES
- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
- A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
- A01N43/00—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds
- A01N43/48—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with two nitrogen atoms as the only ring hetero atoms
- A01N43/50—1,3-Diazoles; Hydrogenated 1,3-diazoles
- A01N43/52—1,3-Diazoles; Hydrogenated 1,3-diazoles condensed with carbocyclic rings, e.g. benzimidazoles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J13/00—Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
- B01J13/02—Making microcapsules or microballoons
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D235/00—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, condensed with other rings
- C07D235/02—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, condensed with other rings condensed with carbocyclic rings or ring systems
- C07D235/04—Benzimidazoles; Hydrogenated benzimidazoles
- C07D235/24—Benzimidazoles; Hydrogenated benzimidazoles with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached in position 2
- C07D235/30—Nitrogen atoms not forming part of a nitro radical
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
- C08F283/02—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G on to polycarbonates or saturated polyesters
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/30—Introducing nitrogen atoms or nitrogen-containing groups
- C08F8/32—Introducing nitrogen atoms or nitrogen-containing groups by reaction with amines
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Environmental Sciences (AREA)
- Medicinal Chemistry (AREA)
- Wood Science & Technology (AREA)
- Zoology (AREA)
- Engineering & Computer Science (AREA)
- Plant Pathology (AREA)
- Pest Control & Pesticides (AREA)
- Polymers & Plastics (AREA)
- Agronomy & Crop Science (AREA)
- Dentistry (AREA)
- Toxicology (AREA)
- Dispersion Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
Abstract
The invention relates to the field of algae removal materials, and aims to solve the problems that the utilization rate of torreya grandis green algae disease treatment by chemical pesticides is low, the period of validity is short, the environment is polluted and the like, which are urgently needed to be solved at present.
Description
Technical Field
The invention relates to the field of algae removal materials, in particular to a modified polylactic acid biological matrix capsule wall material and a method for preparing a bi-molecular structure slow-release algae removal microcapsule by using the same.
Background
Torreya grandis is a special forest industry in Zhejiang province, develops into the most compact forest industry increasing income and becoming rich in the last 10 years, has important strategic position in economic forests, and has unique effect on the economic and social development of Zhejiang. In recent years, the outbreak frequency of the Chinese torreya diseases is improved year by year, the range is enlarged continuously, the economic loss is increased continuously, the diseases become the main bottleneck restricting the health development of the Chinese torreya industry, the harm of the Chinese torreya green algae in primary forests is the most serious, the key technical research of the prevention and control of the major diseases of the Chinese torreya needs to be actively developed, the technical level of major disease control in the Chinese torreya producing area is improved comprehensively, and the scientific and technological guarantee is provided for the sustainable development of the Chinese torreya industry.
Nowadays, torreya grandis green algae is mainly prevented and treated by lime sulphur, and the problems of sulfur residue, short-acting burst release, ecological environment pollution and the like caused by lime sulphur make the torreya grandis green algae full of scale during use. And two types of chemical algicides with high algae killing efficiency: oxidative and flocculating algicides are currently of limited use. The oxidized algicidal product can oxidize enzymes closely related to metabolism in microorganisms, so that the microorganisms are disturbed in metabolism to death. However, the halogenated substances contained in the algicide halogenate organic substances in water, so that carcinogens are generated, and the human health is threatened. The flocculation algicide is mostly heavy metal salt solution, on one hand, the normal metabolism of the algae is inhibited by metal ions to interfere the growth of the algae, on the other hand, the algae is settled by the flocculation of the metal ions to achieve the aim of removing the algae, but the heavy metal pollution is brought. Therefore, the urgent need exists for innovation of torreya grandis green algae disease control technology, improvement of the current high-efficiency torreya grandis green algae algicide to form a new green formulation, or screening of high-efficiency and low-toxicity compounds and development of a novel environment-friendly and safe environment-friendly bio-based algicide.
Disclosure of Invention
In order to solve the problems of low utilization rate, short period of validity, environmental pollution and the like of the torreya grandis green alga disease treatment by chemical pesticides which are urgently needed to be solved at present, the invention provides a modified polylactic acid biological matrix capsule wall material and a method for preparing a bimolecular structure slow-release alga killing microcapsule by using the same, which have the characteristics of high efficiency and low residue, and have very important meanings for prolonging the duration period of the alga killing effect, reducing the application amount of a high-toxicity alga killing agent, efficiently utilizing pesticides and protecting the environment.
The invention is realized by the following technical scheme: a modified polylactic acid biological matrix capsule wall material is prepared by the following steps:
(a) weighing polylactic acid, adding the polylactic acid into a three-neck flask, adding toluene to dissolve the polylactic acid, then placing the polylactic acid into a constant-temperature water bath kettle, heating the polylactic acid to 90-100 ℃, adding maleic anhydride and an initiator, reacting the polylactic acid and the initiator under constant-temperature stirring at 90-100 ℃, wherein the stirring speed is 180-220 r/min, precipitating the polylactic acid with methanol after reacting for 2-3 h, repeatedly washing the polylactic acid with methanol to remove the residual maleic anhydride, and drying the polylactic acid to obtain maleic anhydride grafted modified polylactic acid;
preferably, the mass ratio of the polylactic acid to the maleic anhydride is 1: 0.33-10.2.
Toluene is used as a solvent in an amount sufficient to dissolve the solute, and preferably, the mass ratio of the polylactic acid to the toluene is 1: 5.2-17.2.
Preferably, the mass ratio of the polylactic acid to the initiator is 80-100: 1, and the initiator is 2, 5-dimethyl-2, 5-di-tert-butyl-peroxy-hexane.
(b) Adding a tetrahydrofuran solution containing ethylenediamine into a three-necked flask provided with a stirrer and a thermometer, dissolving maleic anhydride graft modified polylactic acid into tetrahydrofuran, dropwise adding the maleic anhydride graft modified polylactic acid into the tetrahydrofuran solution of the ethylenediamine while stirring, controlling the temperature of a reaction system to be less than or equal to 20 ℃, keeping the temperature for 10-15 minutes after dropwise adding, then raising the temperature to 20-30 ℃ for reaction for 0.5-1 hour, stirring a reaction product to dissolve the reaction product into the tetrahydrofuran, then dropwise adding the reaction product into distilled water, collecting a membrane on the surface, washing the membrane with the distilled water, and repeatedly washing until the pH of a washing solution is 7-9; and drying the collected membrane for 90-100 h at 20-30 ℃ to obtain the modified polylactic acid biological matrix capsule wall material.
Preferably, the mass ratio of the maleic anhydride graft modified polylactic acid to the ethylenediamine is 1: 2-2.5.
Tetrahydrofuran is used as a solvent in an amount sufficient to dissolve the solute, and preferably, the volume ratio of ethylenediamine to tetrahydrofuran is 1: 10 to 1: 12.
The reaction formula is shown as follows:
the method for preparing the bi-molecular structure slow-release algae removal microcapsule by using the modified polylactic acid biological matrix capsule wall material comprises the following steps:
(1) preparation of cinnamoyl algae-killing compound
(1.1) preparation of p-methoxy cinnamaldehyde: tetrahydrofuran is used as a solvent, p-methoxybenzaldehyde and vinyl acetate are added, barium hydroxide is added, the mixture is filtered after stirring for 1.5-2.5 hours at the temperature of 30-45 ℃, an organic layer in filtrate is extracted and separated by using an organic solvent, the organic solvent is removed by using a rotary evaporator to obtain a solid, and yellow p-methoxycinnamaldehyde is obtained after drying for 10-12 hours at the temperature of 30-50 ℃;
preferably, the volume mass ratio of the p-methoxybenzaldehyde to the vinyl acetate to the barium hydroxide is 1 mL: 0.5-1.3 mL: 0.15-0.45 g.
Preferably, the organic solvent is selected from chloroform.
The reaction equation is as follows:
(1.2) preparation of 2-aminobenzimidazole: adding o-phenylenediamine and hydrochloric acid into a reaction container (the reaction container is heated by an oil bath pot) at 85-95 ℃, then dropwise adding cyanamide solution into the reaction system at 5-7 drops/min, reacting for 0.6-1.2 h, then adding a sodium hydroxide solution, continuing to react for 0.6-1.2 h, carrying out suction filtration on a product obtained by the reaction, washing the obtained solid with deionized water, and drying for 10.5-13 h at 50-65 ℃ to obtain light brown 2-aminobenzimidazole;
preferably, the molar ratio of the hydrochloric acid to the o-phenylenediamine is 1.1-1.3: 1, the molar ratio of the cyanamide to the o-phenylenediamine is 1.1-1.2: 1, and the molar ratio of the sodium hydroxide to the o-phenylenediamine is 1.1-1.3: 1.
The mass fraction of the hydrochloric acid is 20-35%, the mass fraction of the cyanamide solution is 45-50%, and the mass fraction of the sodium hydroxide solution is 30-50%.
The reaction equation is as follows:
(1.3) preparing a cinnamoyl algae removal compound: dissolving p-methoxycinnamaldehyde prepared in the step (1.1) and 2-aminobenzimidazole prepared in the step (1.2) in methanol, stirring and reacting at 55-75 ℃ for 0.6-1.2H, carrying out ice bath on the mixed solution, cooling to 0-6 ℃, separating out yellow solid, filtering the solid separated out from the solution, and drying at 35-40 ℃ for 10-12H to obtain N-2- (4-methoxycyclohexyl-2, 4-dienylidene) ethylidene) -1-H-benzyl imidazole-2-amine, namely a cinnamaldehyde algae removal compound;
preferably, the molar ratio of the p-methoxycinnamaldehyde to the 2-aminobenzimidazole is 1: 1.1-1.2;
preferably, the drying method is vacuum drying.
The reaction equation is as follows:
the prepared cinnamaldehyde-based algae removal compound can be decomposed into two monomer substances with algae removal and sterilization effects under the condition of alkaline plant cell sap, so that the expected effect of preventing and treating torreya grandis green algae is achieved.
(2) Preparation of slow-release algae-killing microcapsule with bimolecular structure
Adding the cinnamaldehyde-based algicide into a modified polylactic acid biological matrix capsule wall material/dichloromethane solution, and stirring for 10-20 s at 20-25 ℃ by a homogenizer to form milky white W/O microspheres; 200 to 300 r.min-1Magnetically stirring for 18-20 h to evaporate the organic solvent (dichloromethane) in the microspheres, and then 10000 r.min-1Centrifuging for 10min, and precipitating microspheres; washing with distilled water for several times, centrifuging to collect the product, freeze drying, sealing, and storing at 0-8 deg.C to obtain bilayer structure slow-release algae-killing microcapsule, wherein the reaction scheme is shown in FIG. 5.
Preferably, the mass ratio of the modified polylactic acid biological matrix capsule wall material to the cinnamaldehyde-based algicide is 0.7-1.0: 1.
Methylene chloride acts as an organic solvent and acts as a solvent, and the amount used is that amount which dissolves the solute.
The invention takes polylactic acid as a raw material, gradually grafts and modifies the polylactic acid into amphiphilic molecules (EMPLA), and prepares a novel bio-based molecular capsule wall material; based on cinnamyl aldehyde and 2-aminobenzimidazole as medicament bases with wide sterilization and algae removal functions, a novel intelligent cinnamyl aldehyde algae removal compound of 2-aminobenzimidazole is synthesized by a two-step method; the novel slow-release algae removal microcapsule is prepared by taking the synthesized novel bio-based molecular material as a wall material and the synthesized cinnamaldehyde algae removal compound as a capsule core and adopting an emulsification method. The novel slow-release algae removal microcapsule stage can solve the problem of algae removal of torreya grandis green algae at present, promote the healthy development of torreya grandis industry and lay a foundation for the deep research on the control of torreya grandis major diseases.
Compared with the prior art, the invention has the beneficial effects that: the green environment-friendly slow-release algicide nanocapsule combines the advantages of physical method algae removal, chemical agent algae removal, intelligent material slow-release effect and the like, is a novel dosage form of an environment-friendly algicide and an efficient and low-residue antibacterial pesticide, and has very important significance for prolonging the lasting period of algae removal effect, reducing the application amount of a high-toxicity algicide, efficiently utilizing the pesticide and protecting the environment.
Drawings
FIG. 1 is a hydrogen spectrum of the modified polylactic acid bio-matrix material in example 1;
FIG. 2 is a nuclear magnetic hydrogen spectrum of the cinnamoyl algae-exterminating compound of example 1;
FIG. 3 is an infrared spectrum of a hydrogen spectrum of the modified polylactic acid bio-matrix material in example 1;
FIG. 4 is an infrared spectrum of the cinnamoyl alga-killing compound of example 1;
fig. 5 is a schematic reaction diagram of the bi-molecular structure slow-release algae removal microcapsule.
Detailed Description
The invention is further illustrated by the accompanying drawings and detailed description of specific embodiments, which are intended to illustrate the invention and not to limit it further, and the materials used in the examples are commercially available or may be prepared by conventional methods.
Example 1: preparation of biomass-based molecular capsule wall material
Firstly, weighing 15g of polylactic acid, adding the polylactic acid into a three-neck flask with a stirrer, adding 100mL of toluene for dissolving, then placing the polylactic acid into a constant-temperature water bath kettle, heating the polylactic acid to 95 ℃, adding 5g of maleic anhydride and 0.15g of initiator (2, 5-dimethyl-2, 5-di-tert-butyl-peroxy-hexane), reacting for 2.5 hours at the constant temperature of 95 ℃ under stirring, precipitating with methanol, repeatedly washing with methanol to remove the residual maleic anhydride, and drying to obtain maleic anhydride grafted modified polylactic acid (MPLA). Then 5mL of a THF solution containing 9g of ethylenediamine was added to a three-necked flask equipped with a stirrer and a thermometer; 4.5g of MPLA was completely dissolved in 50mL of THF solution, and the solution was dropped into a three-necked flask with stirring, and the temperature of the reaction system was controlled at 19 ℃. After the dropwise addition is finished, keeping the temperature for ten minutes, raising the temperature to 25 ℃ for reaction for 30 minutes, stirring the reaction product to dissolve in tetrahydrofuran, then dropwise adding excessive distilled water, collecting a membrane on the surface, washing with distilled water, and repeating the operation until the pH value of the washing liquid is 8; and (3) drying the precipitate at 25 ℃ for 96h in vacuum to obtain the modified polylactic acid biological matrix material serving as a capsule wall material.
Preparation example 1: preparation of microcapsule slow-release algicide
(1) Preparation of cinnamaldehyde algae-killing compound
(1.1) preparation of p-methoxy cinnamaldehyde: taking 50mL tetrahydrofuran as a solvent, adding 1mL p-methoxybenzaldehyde and 0.5mL vinyl acetate, then adding 0.2g barium hydroxide, stirring for 2.0h at 40 ℃, filtering the mixture, extracting and separating an organic layer in the filtrate by using an organic solvent chloroform, removing the organic solvent by using a rotary evaporator to obtain a solid, and drying for 10h at 40 ℃ to obtain yellow p-methoxycinnamaldehyde.
(1.2) preparation of 2-aminobenzimidazole: adding 1moL of o-phenylenediamine and 1.2moL of hydrochloric acid with the mass concentration of 20% into a reaction container (heated by an oil bath pot for the reaction container) at 90 ℃, then dropwise adding 1.1moL of cyanamide solution with the mass concentration of 45% into the reaction system at 7 drops/min, reacting for 0.7h, then adding 1.1moL of sodium hydroxide solution with the mass concentration of 30%, continuing to react for 0.7h, carrying out suction filtration on a product obtained by the reaction, washing the obtained solid with deionized water, and carrying out vacuum drying at 60 ℃ for 12h to obtain light brown 2-aminobenzimidazole.
(1.3) preparing a cinnamoyl algae removal compound: dissolving the prepared 1moL of p-methoxycinnamaldehyde and 1.1moL of 2-aminobenzimidazole in methanol, stirring at 65 ℃ for reaction for 0.8H, carrying out ice bath on the mixed solution, cooling to 0 ℃, precipitating yellow solid, filtering the solid precipitated in the solution, and drying at 38 ℃ for 10H to obtain the cinnamoyl algae removal compound (N-2- (4-methoxycyclohexyl-2, 4-dienylidene) ethylidene) -1-H-benzylimidazole-2-amine).
(2) Preparation of microcapsule slow-release algicide
Adding 1g of cinnamaldehyde-based algicide into a solution of modified polylactic acid biological matrix capsule wall material (0.8 g)/dichloromethane (8mL), and stirring for 20s by a homogenizer at 25 ℃ to form milky white W/O microspheres; 300 r.min-1Magnetically stirring for 20h to evaporate dichloromethane from the microspheres, and then 10000 r.min-1Centrifuging for 10min, and precipitating microspheres; washing with distilled water for 3 times, centrifuging to collect product, freeze drying, sealing, and storing at 8 deg.C to obtain bilayer structure slow-release algae-killing microcapsule.
Example 2: preparation of biomass-based molecular capsule wall material
Firstly, weighing 20g of polylactic acid, adding the polylactic acid into a three-neck flask with a stirrer, adding 120mL of toluene to dissolve the polylactic acid, then placing the polylactic acid into a constant-temperature water bath kettle, heating the polylactic acid to 100 ℃, adding 8g of maleic anhydride and 0.2g of initiator (2, 5-dimethyl-2, 5-di-tert-butyl-peroxy-hexane), reacting for 2 hours at 100 ℃ under stirring, precipitating with methanol, repeatedly washing with methanol to remove residual maleic anhydride, and drying to obtain maleic anhydride grafted modified polylactic acid (MPLA). Then 5mL of THF solution containing 10g of ethylenediamine was added to a three-necked flask equipped with a stirrer and a thermometer; 4g of MPLA was completely dissolved in 70mL of THF solution, and the solution was dropped into a three-necked flask with stirring, and the temperature of the reaction system was controlled at 18 ℃. After the dropwise addition, keeping the temperature for 15 minutes, raising the temperature to room temperature (20 ℃) for reaction for 60 minutes, stirring the reaction product to dissolve in tetrahydrofuran, then dropwise adding excessive distilled water, collecting a membrane on the surface, washing with distilled water, and repeating the operation until the washing liquor is neutral in pH (7); and (3) drying the precipitate at room temperature (20 ℃) for 96 hours in vacuum to obtain a modified polylactic acid biological matrix material serving as a capsule wall material.
Preparation example 2: preparation of microcapsule slow-release algicide
(1) Preparation of cinnamaldehyde algae-killing compound
(1.1) preparation of p-methoxy cinnamaldehyde: taking 50mL tetrahydrofuran as a solvent, adding 1mL p-methoxybenzaldehyde and 1mL vinyl acetate, adding 0.3g barium hydroxide, stirring at 45 ℃ for 1.5h, filtering the mixture, extracting and separating an organic layer in the filtrate by using an organic solvent chloroform, removing the organic solvent by using a rotary evaporator to obtain a solid, and drying at 50 ℃ for 12h to obtain yellow p-methoxycinnamaldehyde.
(1.2) preparation of 2-aminobenzimidazole: adding 1moL of o-phenylenediamine and 1.1moL of hydrochloric acid with the mass concentration of 25% into a reaction vessel (heated by an oil bath pot for the reaction vessel) at 90 ℃, then dropwise adding 1.2moL of cyanamide solution with the mass concentration of 50% into the reaction system at 6 drops/min, reacting for 0.7h, then adding 1.2moL of sodium hydroxide solution with the mass concentration of 40%, continuing to react for 0.7h, carrying out suction filtration on a product obtained by the reaction, washing the obtained solid with deionized water, and drying for 11h at 65 ℃ to obtain light brown 2-aminobenzimidazole.
(1.3) preparing a cinnamoyl algae removal compound: dissolving the prepared 1moL of p-methoxycinnamaldehyde and 1.2moL of 2-aminobenzimidazole in methanol, stirring at 70 ℃ for reaction for 1H, carrying out ice bath on the mixed solution, cooling to 3 ℃, precipitating yellow solid, filtering the solid precipitated in the solution, and drying at 35 ℃ for 12H to obtain the cinnamoyl algae removal compound (N-2- (4-methoxycyclohexyl-2, 4-dienylidene) ethylidene) -1-H-benzylimidazole-2-amine).
(2) Preparation of microcapsule slow-release algicide
Adding 1g of cinnamaldehyde-based algicide into a solution of modified polylactic acid biological matrix capsule wall material (1 g)/dichloromethane (10mL), and stirring for 20s by a homogenizer at 20 ℃ to form milky white W/O microspheres; 300 r.min-1Magnetically stirring for 18h to evaporate off the microspheresDichloromethane of (1), then 10000 r.min-1Centrifuging for 10min, and precipitating microspheres; washing with distilled water for 4 times, centrifuging to collect product, freeze drying, sealing, and storing at 0 deg.C to obtain bilayer structure slow-release algae-killing microcapsule.
Example 3: preparation of biomass-based molecular material
Firstly, weighing 15g of polylactic acid, adding the polylactic acid into a three-neck flask with a stirrer, adding 90mL of toluene to dissolve the polylactic acid, then placing the polylactic acid into a constant-temperature water bath kettle, heating the polylactic acid to 90 ℃, adding 5g of maleic anhydride and 0.17g of initiator (2, 5-dimethyl-2, 5-di-tert-butyl-peroxy-hexane), and reacting for 3 hours under stirring at the constant temperature of 90 ℃. And precipitating the solution after the reaction is finished by using methanol, repeatedly washing the solution by using the methanol to remove the residual maleic anhydride, and drying the solution to obtain the maleic anhydride grafted modified polylactic acid (MPLA). Then 5ml of THF solution containing 9g of ethylenediamine was added into a three-necked flask equipped with a stirrer and a thermometer; 3.75g of MPLA was completely dissolved in 60ml of a THF solution, and the solution was dropped into a three-necked flask with stirring, and the temperature of the reaction system was controlled at 17 ℃. After the completion of the dropwise addition, the temperature was maintained for 15 minutes, and then the temperature was raised to room temperature (23 ℃ C.) for 30 minutes. The reaction product is stirred and dissolved in tetrahydrofuran, and then dropped into excess distilled water, and the membrane on the surface is collected and washed with distilled water. Repeating the operation until the pH value of the washing liquid is 9; and (3) drying the precipitate at room temperature (23 ℃) for 100 hours in vacuum to obtain the modified polylactic acid biological matrix material serving as a capsule wall material.
Preparation example 3: preparation of microcapsule slow-release algicide
(1) Preparation of cinnamaldehyde algae-killing compound
(1.1) preparation of p-methoxy cinnamaldehyde: taking 50mL tetrahydrofuran as a solvent, adding 1mL p-methoxybenzaldehyde and 0.8mL vinyl acetate, then adding 0.35g barium hydroxide, stirring for 2.0h at 30 ℃, filtering the mixture, extracting and separating an organic layer in the filtrate by using an organic solvent chloroform, removing the organic solvent by using a rotary evaporator to obtain a solid, and drying for 11h at 30 ℃ to obtain yellow p-methoxycinnamaldehyde.
(1.2) preparation of 2-aminobenzimidazole: adding 1moL of o-phenylenediamine and 1.3moL of hydrochloric acid with the mass concentration of 30% into a reaction vessel (heated by an oil bath pot for the reaction vessel) at 95 ℃, then dropwise adding 1.2moL of cyanamide solution with the mass concentration of 45% into the reaction system at 5 drops/min, reacting for 1.2h, then adding 1.3moL of sodium hydroxide solution with the mass concentration of 35%, continuing to react for 1.2h, carrying out suction filtration on a product obtained by the reaction, washing the obtained solid with deionized water, and drying for 13h at 50 ℃ to obtain light brown 2-aminobenzimidazole.
(1.3) preparing a cinnamoyl algae removal compound: dissolving the prepared 1moL of p-methoxycinnamaldehyde and 1.2moL of 2-aminobenzimidazole in methanol, stirring at 75 ℃ for reaction for 1.2H, carrying out ice bath on the mixed solution, cooling to 6 ℃, precipitating yellow solid, filtering the solid precipitated in the solution, and drying at 40 ℃ for 11H to obtain the cinnamoyl algae removal compound (N-2- (4-methoxycyclohexyl-2, 4-dienylidene) ethylidene) -1-H-benzylimidazole-2-amine).
(2) Preparation of microcapsule slow-release algicide
Adding 1g of cinnamaldehyde-based algicide into a solution of modified polylactic acid biological matrix capsule wall material (0.9 g)/dichloromethane (9mL), and stirring for 15s by a homogenizer at 25 ℃ to form milky white W/O microspheres; 250 r.min-1Magnetically stirring for 20h to evaporate dichloromethane from the microspheres, and then 10000 r.min-1Centrifuging for 10min, and precipitating microspheres; washing with distilled water for several times, centrifuging, collecting product, freeze drying, sealing, and storing at 5 deg.C to obtain bilayer structure slow-release algae-killing microcapsule.
Test example 1
The prepared compounds were tested using a nuclear magnetic resonance spectrometer. And adding a small amount of compound into a nuclear magnetic tube, adding deuterated chloroform to dissolve the sample, and carrying out nuclear magnetic resonance hydrogen spectrum test on the sample. The nuclear magnetic hydrogen spectrum of the modified polylactic acid bio-matrix capsule wall material in example 1 is shown in figure 1, and the nuclear magnetic hydrogen spectrum of the cinnamoyl algae-killing compound in example 1 is shown in figure 2.
The resulting compounds were tested using an infrared spectrometer. And (3) uniformly mixing a small amount of compound powder with potassium bromide, grinding, tabletting, and measuring the infrared spectrum of the mixture within the range of 0-4000 cm < -1 >. The infrared spectrum of the modified polylactic acid bio-matrix capsule wall material in example 1 is shown in fig. 3, and the infrared spectrum of the cinnamoyl algae removal compound in example 1 is shown in fig. 4.
Test example 2
The sensitivity of the torreya grandis green algae to the medicament is determined by adopting a growth rate method. Selecting green algae which usually grows on Chinese torreya, adding a culture medium suitable for the growth of the green algae into a culture dish, adding the slow-release algae removal microcapsule prepared in the preparation example, culturing under the same and suitable conditions, observing the growth condition of the green algae in the culture dish, calculating the concentration of the microcapsule slow-release algae removal agent according to the obtained entrapment rate (EE), and calculating the inhibition rate according to the following method:
the inhibition rates of the sustained-release algae removal microcapsules of the preparation examples 1 and 2 calculated according to the formula are 85.7% and 84.2% respectively, which shows that the nanocapsules have good toxicity to torreya grandis green alga disease.
Test example 3
Actual prevention and control primary effect: the field test is carried out in the main production area of Chinese torreya in Zhejiang province. The typical plots of Chinese torreya tree vigor, soil type and growth system were taken as test points, and 3 treatments were set, namely the slow-release algae-killing microcapsule prepared in preparation example 3 (group K1), 98% cinnamoyl algae-killing compound (group B1) and clear water blank control (group CK). All treatment districts are randomly arranged, each treatment district is 3 Chinese torreya trees, the process is repeated for 3 times, and protection rows are arranged around the treatment districts. The Chinese torreya green algae treatment initial stage is applied by spraying the leaves of the disease (the liquid medicine mass concentration is 12.05 mg.L)-1). The investigation method comprises the following steps: the initial disease condition is investigated on the day of application, the disease condition is investigated on the 4 th and 7 th days later, the number and the level of coverage of the leaves and the green algae are recorded, and the disease index and the prevention and treatment effect are calculated by adopting the following formula. The test results are shown in Table 1.
TABLE 1 field control of hickory dry rot with different algicides
In a field control effect test, the slow-release algae removal microcapsule shows a certain control effect on the treatment of torreya grandis green algae, has a long-term control effect, mainly because the cinnamoyl algae removal compound slowly released by the algae removal capsule has an algae removal effect on green algae, and simultaneously because the medicine in the microcapsule is slowly released, the lasting effect of the medicine can be improved.
Claims (9)
1. A method for preparing a bi-molecular structure slow-release algae removal microcapsule by using a modified polylactic acid biological matrix capsule wall material is characterized by comprising the following steps:
(1) preparation of cinnamaldehyde algicide
(1.1) preparation of p-methoxy cinnamaldehyde: adding p-methoxybenzaldehyde and vinyl acetate into tetrahydrofuran as a solvent, adding barium hydroxide, stirring at 30-45 ℃ for 1.5-2.5 h, filtering the mixture, extracting and separating an organic layer in the filtrate by using an organic solvent, removing the organic solvent to obtain a solid, and drying at 30-50 ℃ for 10-12 h to obtain p-methoxycinnamaldehyde;
(1.2) preparation of 2-aminobenzimidazole: adding o-phenylenediamine and hydrochloric acid into a reaction container at 85-95 ℃, then dropwise adding cyanamide solution into the reaction system at 5-7 drops/min, reacting for 0.6-1.2 h, then adding sodium hydroxide solution, continuing to react for 0.6-1.2 h, performing suction filtration on a product obtained by the reaction, washing the obtained solid with deionized water, and drying at 50-65 ℃ for 10.5-13 h to obtain 2-aminobenzimidazole;
(1.3) preparing a cinnamaldehyde-based algicide: dissolving the p-methoxycinnamaldehyde prepared in the step (1.1) and the 2-aminobenzimidazole prepared in the step (1.2) in methanol, stirring and reacting at 55-75 ℃ for 0.6-1.2 h, carrying out ice bath on the mixed solution, cooling to 0-6 ℃, precipitating solids, filtering the precipitated solids in the solution, and drying at 35-40 ℃ for 10-12 h to obtain the cinnamoyl group algicide with the structural formula shown as the following formula;
(2) preparation of slow-release algae-killing microcapsule with bimolecular structure
Adding the cinnamaldehyde-based algicide into a dichloromethane solution of the modified polylactic acid biological matrix capsule wall material, stirring for 10-20 s at 20-25 ℃, and stirring for 200-300 r.min- 1Stirring for 18-20 h, and then 10000 r.min- 1Centrifuging for 10min, and precipitating microspheres; washing with distilled water for several times, centrifuging to collect the product, freeze-drying, sealing the bottle, and storing at 0-8 ℃ to obtain the bimolecular structure slow-release algae-killing microcapsule;
the modified polylactic acid biological matrix capsule wall material is prepared by the following steps:
(a) adding toluene into polylactic acid for dissolving, then placing the polylactic acid into a constant-temperature water bath kettle, heating to 90-100 ℃, then adding maleic anhydride and an initiator, and reacting under constant-temperature stirring at 90-100 ℃; after reacting for 2-3 h, precipitating with methanol, washing with methanol for a plurality of times, and drying to obtain maleic anhydride grafted modified polylactic acid, wherein the initiator is 2, 5-dimethyl-2, 5-di-tert-butyl-peroxy-hexane;
(b) adding a tetrahydrofuran solution containing ethylenediamine into a container, dissolving maleic anhydride graft modified polylactic acid into tetrahydrofuran, dropwise adding the solution into the tetrahydrofuran solution of ethylenediamine while stirring, controlling the temperature of a reaction system to be less than or equal to 20 ℃, keeping the temperature for 10-15 minutes after the dropwise addition is finished, raising the temperature to 20-30 ℃, reacting for 0.5-1 hour, dissolving a reaction product into the tetrahydrofuran solution, dropwise adding distilled water, collecting a surface film, washing with distilled water, and repeatedly washing until the pH of a washing solution is = 7-9; and drying the collected membrane for 90-100 h at 20-30 ℃ to obtain the modified polylactic acid biological matrix capsule wall material.
2. The method according to claim 1, wherein the mass ratio of polylactic acid to maleic anhydride in step (a) is 1: 0.33-10.2.
3. The method according to claim 1, wherein the mass ratio of the polylactic acid to the initiator in the step (a) is 80-100: 1.
4. The method according to claim 1, wherein the mass ratio of the maleic anhydride graft modified polylactic acid to the ethylenediamine in the step (b) is 1:2 to 2.5.
5. The method according to claim 1, wherein the volume-to-mass ratio of p-methoxybenzaldehyde, vinyl acetate and barium hydroxide in step (1.1) is 1 mL: 0.5-1.3 mL: 0.15 to 0.45 g.
6. The method according to claim 1, wherein the molar ratio of the hydrochloric acid to the o-phenylenediamine in the step (1.2) is 1.1 to 1.3: 1, the molar ratio of cyanamide to o-phenylenediamine is 1.1-1.2: 1, and the molar ratio of sodium hydroxide to o-phenylenediamine is 1.1-1.3: 1.
7. the method according to claim 1 or 6, wherein the mass concentration of the hydrochloric acid is 20% to 35%, the mass concentration of the cyanamide solution is 45% to 50%, and the mass concentration of the sodium hydroxide solution is 30% to 50%.
8. The process according to claim 1, wherein the molar ratio of p-methoxycinnamaldehyde to 2-aminobenzimidazole in step (1.3) is 1: 1.1 to 1.2.
9. The method as claimed in claim 1, wherein the mass ratio of the modified polylactic acid biological matrix material to the cinnamaldehyde-based algicide in the step (2) is 0.7-1.0: 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811356755.XA CN109627361B (en) | 2018-11-14 | 2018-11-14 | Modified polylactic acid biological matrix capsule wall material and method for preparing bimolecular structure slow-release algae-killing microcapsule by using same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811356755.XA CN109627361B (en) | 2018-11-14 | 2018-11-14 | Modified polylactic acid biological matrix capsule wall material and method for preparing bimolecular structure slow-release algae-killing microcapsule by using same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109627361A CN109627361A (en) | 2019-04-16 |
| CN109627361B true CN109627361B (en) | 2021-02-26 |
Family
ID=66068094
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811356755.XA Active CN109627361B (en) | 2018-11-14 | 2018-11-14 | Modified polylactic acid biological matrix capsule wall material and method for preparing bimolecular structure slow-release algae-killing microcapsule by using same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109627361B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112120021B (en) * | 2020-09-30 | 2021-12-14 | 浙江农林大学 | Compound type slow-release algae removal microcapsule and preparation method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002062856A2 (en) * | 2001-02-03 | 2002-08-15 | Clariant Gmbh | Microencapsulated biologically active substances that contain a water-soluble or water-dispersible comb polymer |
| CN1435438A (en) * | 2002-09-24 | 2003-08-13 | 重庆大学 | Diamine modified poly-latic acid, method for preparing same and use thereof |
| CN105557741A (en) * | 2016-03-04 | 2016-05-11 | 扬州大学 | Beta-cypermethrin microcapsule and preparation method thereof |
| CN108383797A (en) * | 2018-03-09 | 2018-08-10 | 浙江农林大学 | A kind of corrosion preventive compound and the preparation method and application thereof |
-
2018
- 2018-11-14 CN CN201811356755.XA patent/CN109627361B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002062856A2 (en) * | 2001-02-03 | 2002-08-15 | Clariant Gmbh | Microencapsulated biologically active substances that contain a water-soluble or water-dispersible comb polymer |
| CN1435438A (en) * | 2002-09-24 | 2003-08-13 | 重庆大学 | Diamine modified poly-latic acid, method for preparing same and use thereof |
| CN105557741A (en) * | 2016-03-04 | 2016-05-11 | 扬州大学 | Beta-cypermethrin microcapsule and preparation method thereof |
| CN108383797A (en) * | 2018-03-09 | 2018-08-10 | 浙江农林大学 | A kind of corrosion preventive compound and the preparation method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109627361A (en) | 2019-04-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH11509402A (en) | Method and apparatus for culturing microalgae in a closed circuit | |
| CN109627361B (en) | Modified polylactic acid biological matrix capsule wall material and method for preparing bimolecular structure slow-release algae-killing microcapsule by using same | |
| Wang et al. | Optimization of microalgal bead preparation with Scenedesmus obliquus for both nutrient removal and lipid production | |
| CN109769807B (en) | Slow-release algae removal microcapsule with bimolecular structure and preparation method thereof | |
| CN113603874B (en) | Polyester based on vanillyl alcohol derivatives, preparation and use as pesticide slow-release agents | |
| JP2014527829A (en) | Method and system for recovering water from a water cell | |
| JPH0680490A (en) | Method for soil modification using soil algae | |
| Hicks | Flower production in the Lemnaceae | |
| CN107473345A (en) | A kind of preparation method of composite algicide | |
| CN109776548B (en) | Biomass-based molecular capsule wall material and method for preparing slow-release algae-killing microcapsule by using same | |
| Guolan et al. | Study on the physiology and degradation of dye with immobilized algae | |
| CN106614810A (en) | Potamogeton malaianus-sodium alginate pellet-type algistat as well as preparation method and application thereof | |
| CN109769806B9 (en) | Slow-release algae removal microcapsule and preparation method thereof | |
| CN107513042A (en) | A kind of method of non-chemical solvent extraction shenqinmycin | |
| CN101538542A (en) | Pseudomonad esterase and application in preparing optical pure mandel and derivative thereof | |
| CN108094420B (en) | Preparation method of modified konjac glucomannan loaded copper sustained release agent and application of modified konjac glucomannan loaded copper sustained release agent in water bloom control | |
| CN113788801A (en) | Compound containing halogenated thiazole structure, preparation method and application thereof | |
| KR101952275B1 (en) | Extraction material and method of propolis | |
| US4402971A (en) | Para-anisole-containing biocide and method for isolating it and using it | |
| CN115321685B (en) | Application of scenedesmus in inhibiting harmful algae in water bloom | |
| CN109468309A (en) | A kind of method that plasm Micro trauma outside imports living cells | |
| CN104974152B (en) | A kind of substituted-tetrahydro quinoline and its hydrolysate and its synthetic method and application | |
| CN108094442A (en) | A kind of preparation method of moss removing agent | |
| CN103555621B (en) | Preparation and regeneration method of algae-lysing bacterium LR5 protoplast for lysing alga | |
| CN1042908A (en) | The bilirubinic method of high-content rapid extraction |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |