Marine biodegradation promoter and marine biodegradable composition having two or more kinds of monovalent organic anions

Abstract

Provided is a marine biodegradation promoter that is a hydrophobic powder composed of a compound in which ionic bonds bond a metal cation having a valence of 2 or higher and two or more monovalent organic anions that have different structures selected from among monovalent organic anions derived from monovalent carboxylic acids, monovalent sulfonic acids, monovalent sulfate esters, and monovalent phosphate esters, said marine biodegradation promoter either dissolving in a 3 mass% aqueous sodium chloride solution, or exhibiting hydrophilicity in a 3 mass% aqueous sodium chloride solution, wherein at least one of the two or more organic anions contains a monovalent hydrocarbon group having 6-30 carbon atoms.

Description

[Technical Field]

[0001] The present invention relates to a marine biodegradation-accelerating agent and a marine biodegradable composition having two or more types of monovalent organic anions. [Background technology]

[0002] In recent years, environmental pollution (marine pollution) and adverse effects on ecosystems caused by microplastics have become a problem, and various efforts have been launched to reduce the environmental burden. Among these efforts, the development and widespread use of biodegradable resins has been attracting attention.

[0003] On the other hand, while typical biodegradable resins exhibit high biodegradability in environments such as soil and sludge where there are many microorganisms responsible for decomposition, they have the disadvantage of being difficult to decompose in environments with extremely low microbial concentrations, such as the ocean (Non-Patent Document 1). Furthermore, even for resins that have been reported to be biodegradable in the ocean, such as polycaprolactone (PCL) and polyhydroxyalkanoic acid (PHA), it has been found that the decomposition rate varies significantly depending on the type of seawater, and it has been reported that this is influenced by various factors, such as the presence or absence of decomposing bacteria in the seawater, the number of bacteria, salt concentration, pH, water temperature, dissolved oxygen concentration, and amount of dissolved organic carbon (Non-Patent Document 2).

[0004] Therefore, there is a need to develop materials that can be reliably decomposed in any type of seawater, and materials that can act as decomposition accelerators for resins that are difficult to biodegrade in seawater. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Hideshige Takada, "Current Status of Microplastic Pollution, International Trends and Countermeasures," Journal of the Japan Society of Material Cycles and Waste Management, Vol. 29, No. 4, pp. 261-269, 2018 [Non-patent document 2] Akira Ebisui and four others, "Decomposition of biodegradable plastics in seawater," Fisheries Engineering, Vol. 40, No. 2, pp. 143-149, 2003 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a biodegradation promoter for promoting the biodegradation of resins and the like, particularly in the ocean, and a marine biodegradable composition containing the biodegradation promoter. [Means for solving the problem]

[0007] As a result of extensive research aimed at solving the above-mentioned problems, the inventors discovered that a hydrophobic powder material consisting of a compound in which two or more structurally different monovalent organic anions selected from carboxylic acids, sulfonic acids, sulfates, and phosphates are ionic bonds with a divalent or higher metal cation is insoluble in freshwater and, despite its hydrophobic nature, gradually dissolves or becomes hydrophilic in seawater. Unlike typical biodegradable resins, the primary decomposition (decomposition into smaller molecules) in seawater is not primarily due to hydrolysis or enzymes or microorganisms, but rather to molecular cleavage by metal ions such as sodium. Therefore, this material undergoes stable primary decomposition regardless of the type of seawater, and is decomposed into smaller molecules that dissolve or are compatible with seawater, greatly promoting hydrolysis and decomposition by enzymes and microorganisms. Furthermore, by using this material in combination with a resin, particularly a biodegradable resin, the material undergoes primary decomposition in seawater first, resulting in (1) the formation of pores in the resin material, which increases the specific surface area of ​​the resin and promotes the growth of microorganisms responsible for decomposition, and (2) the primary decomposition has the effect of promoting secondary decomposition, i.e., biodegradation by microorganisms, thereby ultimately promoting the biodegradation of resin materials in the ocean, thereby completing the present invention.

[0008] That is, the present invention provides a marine biodegradation-accelerating agent and a marine biodegradable composition having the following hydrocarbon group: 1. A marine biodegradation accelerator which is a hydrophobic powder consisting of a compound in which two or more monovalent organic anions different in structure from each other, selected from monovalent organic anions derived from monovalent carboxylic acids, monovalent sulfonic acids, monovalent sulfate esters, and monovalent phosphate esters, are bonded by ionic bonds to a divalent or higher metal cation, and which dissolves in a 3% by mass aqueous sodium chloride solution or exhibits hydrophilicity in a 3% by mass aqueous sodium chloride solution, The marine biodegradation promoter, wherein at least one of the two or more organic anions has a monovalent hydrocarbon group having 6 to 30 carbon atoms. 2. The marine biodegradation accelerator according to 1, wherein all of the two or more monovalent organic anions have a monovalent hydrocarbon group having 6 to 30 carbon atoms. 3. The marine biodegradation accelerator according to 1 or 2, wherein the monovalent hydrocarbon group has 10 to 25 carbon atoms. 4. The marine biodegradation accelerator according to any one of 1 to 3, wherein the monovalent organic anion is derived from a monocarboxylic acid. 5. The marine biodegradation accelerator according to 4, wherein the monocarboxylic acid is a fatty acid having a monovalent hydrocarbon group with 6 to 30 carbon atoms or an amino acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms. 6. The marine biodegradation promoter according to 5, wherein the amino acid derivative is a sarcosinic acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms or a glutamic acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms. 7. The marine biodegradation-accelerating agent according to any one of 1 to 6, wherein the monovalent organic anion does not contain a ring structure. 8. The marine biodegradation accelerator according to any one of 1 to 7, wherein the monovalent organic anion contains an amide group. 9. The marine biodegradation accelerator according to any one of 1 to 8, wherein the metal cation is a calcium ion, a magnesium ion, or an aluminum ion. 10. A marine biodegradation accelerator according to any one of 1 to 9, which is a compound having a molecular weight of 100 to 5,000. 11. A marine biodegradation accelerator according to any one of 1 to 10, which is a powder having an average particle size of 0.1 to 10,000 μm. 12. A marine biodegradation accelerator according to any one of 1 to 11, which is a thermoplastic powder. 13. Marine biodegradation accelerator 12, which is a thermoplastic powder with a melting temperature of 60-200°C. 14. A marine biodegradation accelerator according to any one of 1 to 13, wherein when a water droplet is dropped onto a molten molded body of a particle group made of the powder, the contact angle after 30 seconds is 50° or more. 15. A marine biodegradable resin composition comprising the marine biodegradation promoter according to any one of 1 to 14 and a resin. 16. The marine biodegradable resin composition of 15, wherein the resin is a biodegradable resin. 17. The marine biodegradable resin composition of 15 or 16, wherein the content of the marine biodegradation promoter is 3 to 50 mass % and the content of the biodegradable resin is 50 to 97 mass %. 18. A molded article obtained from the marine biodegradable resin composition according to any one of 15 to 17. [Effects of the Invention]

[0009] The marine biodegradation promoter of the present invention dissolves or becomes hydrophilic in seawater, and therefore compositions and molded articles containing the same are accelerated in the ocean for biodegradation, making them useful as a measure against marine pollution. By using the marine biodegradation promoter of the present invention, environmentally friendly compositions and molded articles can be obtained. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is an SEM photograph (200x magnification) of the film of Example 4-1 after immersion in water for 45 days. [Figure 2] 1 is an SEM photograph (200x magnification) of the film of Example 4-1 taken 45 days after it was immersed in a 3 mass % aqueous sodium chloride solution. [Figure 3] 1 is an SEM photograph (500x magnification) of the film of Example 5-2 taken 45 days after immersion in water. [Figure 4] 1 is an SEM photograph (500x magnification) of the film of Example 5-2 taken 45 days after it was immersed in a 3 mass % aqueous sodium chloride solution. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Marine biodegradation accelerator] The marine biodegradation-accelerating agent of the present invention is a hydrophobic powder consisting of a compound (hereinafter also referred to as a hydrophobized compound) in which two or more structurally different monovalent organic anions selected from monovalent organic anions derived from monovalent carboxylic acids, monovalent sulfonic acids, monovalent sulfate esters, and monovalent phosphate esters are bonded by ionic bonds to a divalent or higher metal cation, and the compound dissolves in a 3% by mass aqueous sodium chloride solution or exhibits hydrophilicity in a 3% by mass aqueous sodium chloride solution, and at least one of the two or more organic anions has a monovalent hydrocarbon group having 6 to 30 carbon atoms.

[0012] The monovalent hydrocarbon group preferably has 10 to 25 carbon atoms, more preferably has 12 to 25 carbon atoms, and even more preferably has 14 to 20 carbon atoms.

[0013] It is preferable that all of the two or more types of monovalent organic anions have a monovalent hydrocarbon group having 6 to 30 carbon atoms.

[0014] The monovalent organic anion is preferably derived from the monocarboxylic acid or monosulfonic acid, and more preferably derived from the monocarboxylic acid. Furthermore, the monocarboxylic acid is preferably a fatty acid having a monovalent hydrocarbon group with 10 to 25 carbon atoms or an amino acid derivative having a monovalent hydrocarbon group with 10 to 25 carbon atoms. These monovalent organic anions are preferred because they are characterized by their ability to easily attract bacteria, which are scarce in the ocean.

[0015] From the viewpoint of promoting biodegradability, the monovalent organic anion preferably does not contain a ring structure, but from the viewpoint of imparting physical properties, a ring structure may be introduced to the extent that biodegradability and its control are not impaired.

[0016] The monovalent organic anion preferably has an amide group.

[0017] The two or more monovalent organic anions having different structures preferably differ in at least one of the number of carbon atoms in the monovalent hydrocarbon group, the necessity of an amino group, and the type of anionic substituent (carboxylate anion, sulfonate anion, sulfate ester anion, phosphate ester anion), and particularly preferably differ in composition formula.

[0018] The divalent or higher metal cation is not particularly limited, but examples thereof include magnesium ion, calcium ion, aluminum ion, strontium ion, barium ion, radium ion, scandium ion, titanium ion, vanadium ion, chromium ion, manganese ion, iron ion, cobalt ion, nickel ion, copper ion, zinc ion, yttrium ion, zirconium ion, niobium ion, molybdenum ion, technetium ion, ruthenium ion, rhodium ion, palladium ion, silver ion, cadmium ion, lead ion, platinum ion, gold ion, etc. Among these, calcium ion, magnesium ion, aluminum ion, zinc ion, iron ion, copper ion, and barium ion are preferred, and calcium ion, magnesium ion, and aluminum ion are preferred from the viewpoint of safety, and calcium ion and magnesium ion are more preferred from the viewpoint of the environment, with calcium ion being the most preferred.

[0019] The powder comprising the hydrophobizing compound is prepared by dispersing the powder in a 3% by mass aqueous sodium chloride solution to a concentration of 0.1% by mass. After 15 days, the transmittance of the dispersion at a wavelength of 560 nm is defined as SD1 (%). The marine biodegradation promoter is dispersed in water to a concentration of 0.1% by mass. After 15 days, the transmittance of the dispersion at a wavelength of 560 nm is defined as WD1 (%). The ratio WD1 / SD1 is preferably 0.9 or less, more preferably 0.8 or less, and even more preferably 0.6 or less. If the ratio is 0.9 or less, the shape of the marine biodegradation promoter particles changes, and the phenomenon of dissolution and transparency can be observed. The lower limit of WD1 / SD1 is not particularly limited, but is typically around 0.1. From the perspective of environmental considerations and biodegradation promotion effects, it is preferable that WD1 / SD1 be at least 0.9 or less within approximately 15 days.

[0020] When the hydrophobizing compound is designed to have sufficient solubility in water or salt water and biodegradability in the environment from an environmental perspective, it preferably has a molecular weight of 5,000 or less, more preferably 100 to 5,000, further preferably 150 to 3,000, 200 to 2,000, and most preferably 250 to 1,000. In the present invention, the molecular weight refers to the number average molecular weight (Mn) for polymers, where Mn is a polystyrene-equivalent value measured by gel permeation chromatography. For substances other than polymers, it refers to the chemical formula weight.

[0021] The powder made of the hydrophobic compound preferably has an average particle size of 0.1 to 10,000 μm, more preferably 1.0 to 5,000 μm, and even more preferably 3.0 to 3,000 μm. In particular, when the powder is used solely as primary particles, the average particle size is preferably 3.0 to 500 μm. In the present invention, the average particle size is the volume average particle size (MV) measured by the laser diffraction / scattering method.

[0022] The powder made of the hydrophobic compound is preferably a thermoplastic powder, and particularly preferably one having a melting temperature of 60 to 200°C. A melting temperature within this range allows the powder to be thermally melted and mixed uniformly with the resin, making it possible to uniformly and efficiently generate biodegradable starting points in the ocean. This is also preferable in that homogenization can control variations in physical properties such as strength. The melting temperature is more preferably 70 to 180°C, and even more preferably 90 to 160°C. When mixed with the resin, it is preferable to adjust the powder's melting temperature to within ±20°C of the resin's melting temperature.

[0023] The shape of the powder is not particularly limited and may be physically or chemically shape-controlled such as spherical, approximately spherical, flat, dimpled, etc., or physically pulverized, but from the viewpoint of controlling texture, slipperiness, and particle size distribution, physically or chemically shape-controlled such as spherical, approximately spherical, flat, dimpled, etc. is preferred. The particle group consisting of the marine biodegradation accelerator may be compression molded or melt molded into pellets.

[0024] It is preferable that a water droplet be dropped on a melt-molded body of the particle group made of the powder, and the contact angle after 30 seconds be 50° or more. The melt-molded body is a sheet for contact angle measurement, which is made by heating and melting particles to form a molded body. In this case, the hydrophobic effect, solubility in seawater, and decomposition property are fully exhibited. Since the above effects are easily obtained, the contact angle is preferably 60° or more, 70° or more, and 80° or more, in this order. The upper limit of the contact angle is not particularly limited, but practical values ​​are 170° or less, 160° or less, 150° or less, and 140° or less. Considering the practical hydrophobic effect, the time required for dissolution in seawater and biodegradation, etc., the contact angle is preferably 50° to 160°, more preferably 50° to 150°, even more preferably 60° to 140°, and most preferably 70° to 130°. The contact angle can be measured using a contact angle meter (for example, Drop Master 300 manufactured by Kyowa Interface Science Co., Ltd.).

[0025] The hydrophobic compound is obtained by reacting two or more compounds (hereinafter also referred to as raw material compound A) consisting of a monovalent organic anion derived from one selected from a monovalent carboxylic acid, a monovalent sulfonic acid, a monovalent sulfate ester, and a monovalent phosphate ester, and a monovalent cation, with a polyvalent metal salt containing a divalent or higher metal cation, thereby bonding the monovalent organic anion with the divalent or higher metal cation.

[0026] The monovalent organic anion is a carboxylate anion (-COO - ), sulfonate anion (-SO3 - ), sulfate anion (-O-SO3 - ) or phosphate anion (-P(=O)(OH)-O - ) is an anion having the formula:

[0027] From an environmental viewpoint, the monovalent cation may be a monovalent metal ion such as a hydrogen ion, a lithium ion, a sodium ion, a potassium ion, or a silver ion; or a monovalent organic ion such as an ammonium cation. Among these, from the viewpoints of the environment, biosafety, versatility, cost, etc., sodium ion, potassium ion, or ammonium cation is preferred, sodium ion or potassium ion is more preferred, and sodium ion is even more preferred.

[0028] The molecular weight of raw material compound A is preferably 100 to 2,500. When the molecular weight is within this range, the physical properties of a resin, such as thermal fusibility, and compatibility with other resins are maintained, the resin is compatible with seawater, and decomposition is facilitated. The lower limit of the molecular weight is preferably 150 or more and 200 or more. On the other hand, the upper limit is preferably 2,000 or less, 1,500 or less, 1,000 or less, and 500 or less, in that order. In particular, the molecular weight of raw material compound A is preferably 150 to 800, more preferably 150 to 600, and even more preferably 200 to 500.

[0029] Furthermore, it is preferable that the raw material compound A is soluble in water at room temperature or at a temperature of 80° C. or less, since such a compound will be well soluble in seawater and will provide a good biodegradation rate.

[0030] Examples of the raw material compound A include monocarboxylic acids or salts thereof, monosulfonic acids or salts thereof, monosulfuric acid esters or salts thereof, and monophosphate esters or salts thereof.

[0031] The monocarboxylic acid salt is a salt consisting of an anion derived from a monocarboxylic acid and a monovalent cation. The monocarboxylic acid is preferably a carboxylic acid having a monovalent hydrocarbon group with 6 to 30 carbon atoms. Particularly preferred examples of the monocarboxylic acid salt include salts consisting of an anion derived from a fatty acid having a monovalent hydrocarbon group with 6 to 30 carbon atoms and a monovalent cation, and salts consisting of an anion derived from an amino acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms and a monovalent cation.

[0032] Examples of the fatty acids include caproic acid, enanthic acid, caprylic acid, octylic acid, pelargonic acid, capric acid, undecylenic acid, lauric acid, myristic acid, pentadecylic acid, palmitic acid, palmitoleic acid, margaric acid, stearic acid, isostearic acid, oleic acid, vaccenic acid, ricinoleic acid, linoleic acid, linolenic acid, eleostearic acid, oxystearic acid, ricinoleic acid, arachidic acid, mead acid, arachidonic acid, eicosapentaenoic acid, behenic acid, docosahexaenoic acid, lignoceric acid, nervonic acid, cerotic acid, montanic acid, melissic acid, coconut oil fatty acid, palm oil fatty acid, etc. Branched isomers of these fatty acids may also be used.

[0033] The fatty acid salt is preferably a monovalent metal salt, and specific examples thereof include caprylic acid salts such as potassium caprylate and sodium caprylate; octylic acid salts such as potassium octylate and sodium octylate; pelargonates such as potassium pelargonate and sodium pelargonate; capric acid salts such as potassium caprate and sodium caprate; undecylenates such as potassium undecylenate and sodium undecylenate; lauric acid salts such as potassium laurate and sodium laurate; myristates such as potassium myristate and sodium myristate; pentadecylic acid salts such as potassium pentadecylate and sodium pentadecylate; palmitates such as potassium palmitate and sodium palmitate; potassium margarate and margarine Examples include margarates such as sodium phosphate; stearates such as potassium stearate and sodium stearate; isostearates such as potassium isostearate and sodium isostearate; oleates such as potassium oleate and sodium oleate; linoleates such as potassium linoleate and sodium linoleate; linolenates such as potassium linolenate and sodium linolenate; arachidates such as potassium arachidate and sodium arachidate; arachidonates such as potassium arachidonate and sodium arachidonate; behenates such as potassium behenate and sodium behenate; docosahexaenoates such as sodium docosahexaenoate; and coconut oil fatty acid salts such as potassium coconut oil fatty acid and sodium coconut oil fatty acid. Of these, fatty acid salts having a monovalent hydrocarbon group having 10 to 20 carbon atoms, such as laurate, myristate, palmitate, stearate, and arachidate, are preferred.

[0034] The amino acid derivative salt preferably has a monovalent hydrocarbon group having 6 to 30 carbon atoms, more preferably has a monovalent hydrocarbon group having 10 to 25 carbon atoms, and even more preferably has a monovalent hydrocarbon group having 12 to 20 carbon atoms. The amino acid derivative salt is preferably a monovalent salt, and more preferably a monovalent metal salt.

[0035] Examples of the amino acid derivatives include sarcosine derivatives such as capryloyl sarcosine, lauroyl sarcosine, myristoyl sarcosine, palmitoyl sarcosine, and coconut oil fatty acid sarcosine; glutamic acid derivatives such as capryloyl glutamic acid, lauroyl glutamic acid, myristoyl glutamic acid, palmitoyl glutamic acid, stearoyl glutamic acid, coconut oil fatty acid acyl glutamic acid, cocoyl glutamic acid, acyl glutamic acid, and dilauryl glutamic acid; glycine derivatives such as lauroyl glycine, myristoyl glycine, palmitoyl glycine, palmitoyl methyl glycine, coconut oil fatty acid acyl glycine, and cocoyl glycine; lauryl methyl alanine, myristoyl methyl alanine, cocoyl alanine, and coconut oil fatty acid methyl glycine. Examples of such amino acid derivatives include alanine derivatives such as acetylalanine; lysine derivatives such as lauroyl lysine, myristoyl lysine, palmitoyl lysine, stearoyl lysine, oleyl lysine, and acylated lysine; aspartic acid derivatives such as lauroyl aspartic acid, myristoyl aspartic acid, palmitoyl aspartic acid, and stearoyl aspartic acid; taurine derivatives such as lauroyl taurine, lauroyl methyl taurine, myristoyl taurine, myristoyl methyl taurine, palmitoyl taurine, palmitoyl methyl taurine, stearoyl taurine, and stearoyl methyl taurine; and proline derivatives such as lauroyl proline, myristoyl proline, and palmitoyl proline. N-acyl derivatives of amino acids are particularly preferred. Furthermore, the amino acid derivative is preferably a sarcosinic acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms or a glutamic acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms.

[0036] Examples of the amino acid derivative salts include sarcosine derivative salts such as potassium capryloyl sarcosine, sodium capryloyl sarcosine, potassium lauroyl sarcosine, sodium lauroyl sarcosine, potassium myristoyl sarcosine, sodium myristoyl sarcosine, potassium palmitoyl sarcosine, sodium palmitoyl sarcosine, potassium coconut oil fatty acid sarcosine, and sodium coconut oil fatty acid sarcosine; potassium capryloyl glutamate, sodium capryloyl glutamate, and lauroyl glutamate. Potassium lauroyl glutamate, sodium lauroyl glutamate, potassium myristoyl glutamate, sodium myristoyl glutamate, sodium palmitoyl glutamate, potassium palmitoyl glutamate, potassium stearoyl glutamate, sodium stearoyl glutamate, potassium cocoyl glutamate, sodium cocoyl glutamate, potassium acyl glutamate, sodium acyl glutamate, dilauroyl glutamate salts of glutamic acid derivatives such as sodium lauroyl glutamate lysine and sodium polyglutamate; salts of glycine derivatives such as potassium lauroyl glycine, sodium lauroyl glycine, potassium myristoyl glycine, sodium myristoyl glycine, sodium palmitoyl glycine, sodium palmitoyl methyl glycine, potassium coconut oil fatty acid acyl glycine, sodium coconut oil fatty acid acyl glycine, potassium cocoyl glycine, sodium cocoyl glycine; salts of alanine derivatives such as potassium lauroyl methyl alanine, sodium lauryl methyl alanine, sodium myristoyl methyl alanine, sodium cocoyl alanine, and sodium coconut oil fatty acid methyl alanine; salts of aspartic acid derivatives such as potassium lauroyl aspartate, sodium lauroyl aspartate, potassium myristoyl aspartate, sodium myristoyl aspartate, potassium palmitoyl aspartate, sodium palmitoyl aspartate, potassium stearoyl aspartate, and sodium stearoyl aspartate;Examples of suitable taurine derivatives include sodium lauroyl taurate, potassium lauroyl taurate, sodium lauroyl methyl taurate, potassium myristoyl taurate, sodium myristoyl taurate, sodium myristoyl methyl taurate, potassium palmitoyl taurate, sodium palmitoyl taurate, potassium palmitoyl methyl taurate, sodium palmitoyl methyl taurate, potassium stearoyl taurate, sodium stearoyl taurate, and sodium stearoyl methyl taurate; and amino acid derivative salts having a hydrocarbon group, such as proline derivative salts, such as sodium lauroyl proline, sodium myristoyl proline, and sodium palmitoyl proline. N-acyl amino acid derivative salts are particularly preferred. Among these, sarcosine derivative salts of lauric acid, myristic acid, or palmitic acid, and glutamic acid derivative salts of lauric acid, myristic acid, palmitic acid, or stearic acid are particularly suitable from the standpoints of marine biodegradability and its adjustment, melting temperature adjustment, and safety for the human body.

[0037] The sulfonate preferably has a monovalent hydrocarbon group having 6 to 30 carbon atoms, more preferably has a monovalent hydrocarbon group having 10 to 25 carbon atoms, and even more preferably has a monovalent hydrocarbon group having 12 to 20 carbon atoms. The sulfonate is preferably a monovalent salt, more preferably an ammonium salt or a monovalent metal salt. Specific examples thereof include alkyl sulfonates such as sodium lauryl sulfonate, ammonium lauryl sulfonate, sodium myristyl sulfonate, ammonium myristyl sulfonate, sodium cetyl sulfonate, ammonium cetyl sulfonate, sodium stearyl sulfonate, ammonium stearyl sulfonate, sodium oleyl sulfonate, and ammonium oleyl sulfonate; dodecyl benzene sulfonates such as ammonium dodecyl benzene sulfonate and sodium dodecyl benzene sulfonate; dialkyl succinate sulfonates such as sodium dialkyl succinate sulfonate; and monoalkyl succinate salts such as disodium monoalkyl succinate sulfonate. Examples of suitable sulfonates include octanoate sulfonates; naphthalenesulfonic acid-formaldehyde condensate salts such as sodium naphthalenesulfonic acid-formaldehyde condensate; olefin sulfonates such as sodium tetradecenesulfonate and ammonium tetradecenesulfonate; isethionates such as potassium lauroylisethionate, sodium lauroylisethionate, sodium myristoylisethionate, sodium palmitoylisethionate, and sodium stearoylisethionate; and sulfosuccinates such as sodium dihexyl sulfosuccinate, sodium dioctyl sulfosuccinate, ammonium dioctyl sulfosuccinate, sodium didecyl sulfosuccinate, and sodium diisobutyl sulfosuccinate. Among these, sulfonates having an alkyl group having 12 to 20 carbon atoms are particularly preferred.

[0038] Examples of the sulfate salts include alkyl sulfate salts, polyoxyethylene aryl ether sulfate salts, polyoxyethylene alkyl ether sulfate salts, polyoxyalkylene alkyl ether sulfate salts, polyoxyalkylene alkenyl ether sulfate salts, polyoxyethylene castor oil ether sulfate salts, etc. The sulfate salts are preferably monovalent salts, more preferably ammonium salts or monovalent metal salts.

[0039] Specifically, the alkyl sulfate salt preferably has an alkyl group having 6 to 30 carbon atoms, more preferably has an alkyl group having 10 to 25 carbon atoms, and even more preferably has an alkyl group having 12 to 20 carbon atoms. Specific examples thereof include potassium lauryl sulfate, sodium lauryl sulfate, ammonium lauryl sulfate, potassium myristyl sulfate, sodium myristyl sulfate, ammonium myristyl sulfate, sodium cetyl sulfate, ammonium cetyl sulfate, sodium stearyl sulfate, ammonium stearyl sulfate, sodium oleyl sulfate, and ammonium oleyl sulfate.

[0040] The polyoxyethylene aryl ether sulfate salts preferably have an HLB value of 16 or less, and more preferably 12 or less. Specific examples thereof include polyoxyethylene polycyclic phenyl ether sulfate salts such as sodium polyoxyethylene polycyclic phenyl ether sulfate and ammonium polyoxyethylene polycyclic phenyl ether sulfate; sodium polyoxyethylene aryl ether sulfate; and the like.

[0041] The polyoxyethylene alkyl ether sulfate salts preferably have an HLB value of 16 or less, and more preferably 12 or less. Specific examples thereof include polyoxyethylene alkyl ether sulfates, polyoxyethylene lauryl ether sodium sulfate, polyoxyethylene lauryl ether ammonium sulfate, polyoxyethylene myristyl ether sodium sulfate, polyoxyethylene myristyl ether ammonium sulfate, polyoxyethylene cetyl ether sodium sulfate, polyoxyethylene cetyl ether ammonium sulfate, polyoxyethylene stearyl ether sodium sulfate, polyoxyethylene stearyl ether ammonium sulfate, polyoxyethylene oleyl ether sodium sulfate, and polyoxyethylene oleyl ether ammonium sulfate.

[0042] The polyoxyalkylene alkyl ether sulfate salts preferably have an HLB value of 16 or less, more preferably 12 or less. Specific examples include sodium sulfate of a polyoxyethylene-polyoxypropylene block copolymer, sodium sulfate of a polyoxyethylene-polyoxybutylene block copolymer, and sodium sulfate of an alkyl ether of a polyoxyethylene-polyoxypropylene block copolymer. The polyoxyalkylene alkenyl ether sulfate salts preferably have an HLB value of 16 or less, more preferably 12 or less. Specific examples include ammonium sulfate of an alkenyl ether of a polyoxyethylene-polyoxyalkylene block copolymer. The polyoxyethylene castor oil ether sulfate esters and salts thereof preferably have an HLB value of 16 or less, more preferably 12 or less. Specific examples include polyoxyethylene castor oil ether sulfate esters and ammonium polyoxyethylene castor oil ether sulfate esters.

[0043] Examples of the phosphate salts include alkyl phosphate salts. The alkyl phosphate salts preferably have an alkyl group having 6 to 30 carbon atoms, more preferably have an alkyl group having 10 to 25 carbon atoms, and even more preferably have an alkyl group having 12 to 20 carbon atoms. Specific examples include octyl phosphates such as potassium octyl phosphate; nonyl phosphates such as potassium nonyl phosphate; decyl phosphates such as potassium decyl phosphate; undecyl phosphates such as potassium undecyl phosphate; lauryl phosphates such as potassium lauryl phosphate; myristyl phosphates such as potassium myristyl phosphate; cetyl phosphates such as potassium cetyl phosphate and sodium cetyl phosphate; and stearyl phosphates such as potassium stearyl phosphate.

[0044] In addition to the above-mentioned compounds, the raw material compound A may be a compound having an active functional group to which a carboxylate anion (-COO - ), sulfonate anion (-SO3 - ), sulfate anion (-O-SO3 - ) and phosphate anion (-P(=O)(OH)-O - It is also possible to use a compound consisting of a monovalent cation and an anion having a structure in which a monovalent anionic substituent selected from the group consisting of: a hydroxy group, an amino group, a carboxy group, etc. In the present invention, the active functional group refers to a functional group capable of undergoing a condensation reaction, such as a hydroxy group, an amino group, or a carboxy group.

[0045] The compound having the active functional group is preferably a compound having a hydroxy group, such as a monohydric alcohol, a monovalent amino compound, a (poly)alkylene glycol ether, or a (poly)alkylene glycol ester. In addition, the monovalent anionic substituent to be introduced into the compound having the active functional group is preferably -COO because it is easy to introduce. - is preferred.

[0046] The monohydric alcohol is an alcohol having a monovalent hydrocarbon group having 10 to 25 carbon atoms and one hydroxy group, and more preferably having 12 to 20 carbon atoms. The monohydric alcohol may be linear, branched, or cyclic, but linear alcohols are preferred. Specific examples of the monohydric alcohol include hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, icosanol, henicosanol, docosanol, tricosanol, tetracosanol, pentacosanol, hexacosanol, heptacosanol, octacosanol, nonacosanol, and triacontanol.

[0047] The monovalent amino compound is a compound having a monovalent hydrocarbon group having 10 to 25 carbon atoms and one amino group, and more preferably having 12 to 20 carbon atoms. The monovalent amino compound may be linear, branched, or cyclic, but linear compounds are more preferred. Specific examples include aminohexane, aminoheptane, aminooctane, aminononane, aminodecane, aminoundecane, aminododecane, aminotridecane, aminotetradecane, aminopentadecane, aminohexadecane, aminoheptadecane, aminooctadecane, aminononadecane, and aminoicosane.

[0048] The (poly)alkylene glycol ether preferably has an HLB value of 16 or less, more preferably 12 or less, and even more preferably 8 or less. Specific examples thereof include (poly)alkylene glycol monoalkyl ethers such as (poly)ethylene glycol monododecyl ether, (poly)ethylene glycol monomyristyl ether, (poly)ethylene glycol monocetyl ether, (poly)ethylene glycol monostearyl ether, (poly)ethylene glycol monooleyl ether, (poly)ethylene glycol monobehenyl ether, (poly)propylene glycol monododecyl ether, (poly)propylene glycol monomyristyl ether, (poly)propylene glycol monocetyl ether, (poly)propylene glycol monostearyl ether, (poly)propylene glycol monooleyl ether, and (poly)propylene glycol monobehenyl ether; and (poly)alkylene glycol monoaryl ethers such as (poly)ethylene glycol monophenyl ether and (poly)propylene glycol monophenyl ether.

[0049] The (poly)alkylene glycol ester preferably has an HLB value of 16 or less, more preferably 12 or less, and even more preferably 8 or less. Specific examples thereof include polyalkylene glycol monofatty acid esters such as (poly)ethylene glycol monolaurate, (poly)ethylene glycol monomyristate, (poly)ethylene glycol monopalmitate, (poly)ethylene glycol monostearate, (poly)ethylene glycol monooleate, (poly)ethylene glycol monoisostearate, (poly)ethylene glycol monoarachidate, (poly)ethylene glycol monobehenate, (poly)propylene glycol monolaurate, (poly)propylene glycol monomyristate, (poly)propylene glycol monopalmitate, (poly)propylene glycol monostearate, (poly)propylene glycol monooleate, (poly)propylene glycol monoisostearate, (poly)propylene glycol monoarachidate, and (poly)propylene glycol monobehenate. and polyalkylene sorbitan monofatty acid esters such as (poly)ethylene sorbitan monolaurate, (poly)ethylene sorbitan monomyristate, (poly)ethylene sorbitan monopalmitate, (poly)ethylene sorbitan monostearate, (poly)ethylene sorbitan monooleate, (poly)ethylene sorbitan monoisostearate, (poly)ethylene sorbitan monoarachidate, (poly)ethylene sorbitan monobehenate, (poly)propylene sorbitan monolaurate, (poly)propylene sorbitan monomyristate, (poly)propylene sorbitan monopalmitate, (poly)propylene sorbitan monostearate, (poly)propylene sorbitan monooleate, (poly)propylene sorbitan monoisostearate, (poly)propylene sorbitan monoarachidate, and (poly)propylene sorbitan monobehenate.

[0050] The number average molecular weight (Mn) of the polyalkylene glycol ether and (poly)alkylene glycol ester preferably has a lower limit of 100 or more, 300 or more, 400 or more, and 500 or more, in that order, and preferably has an upper limit of 10,000 or less, 6,000 or less, 4,000 or less, 3,000 or less, and 2,000 or less, in that order.

[0051] The monovalent anionic substituent can be introduced into the compound having the active functional group by, for example, -COO - When introducing -SO3, for example, a method of esterifying a compound having the active functional group with a dicarboxylic acid anhydride in the presence of a monovalent metal salt, or a method of reacting a monovalent metal with a metal alkoxide to form a metal alkoxide, and then esterifying the metal alkoxide with a dicarboxylic acid anhydride, can be used. As the dicarboxylic acid anhydride, succinic anhydride, maleic anhydride, and phthalic anhydride are preferred, and succinic anhydride and maleic anhydride are more preferred in terms of biodegradability. In addition, for example, -SO3 - To introduce the above, a method of reacting a compound having a hydroxyl group or an amino group as the active functional group with SO3 or an SO3·Lewis base complex in an aprotic polar solvent can be used. Examples of the Lewis base include tertiary amines, pyridine, and DMF. Acetonitrile is preferred as the aprotic polar solvent. These reactions can be carried out by known methods.

[0052] [Method of producing hydrophobic compounds] The hydrophobic compound can be produced by the following methods (1) and (2). (1) A method (Method 1) comprising the steps of forming a W / O emulsion containing two or more raw material compounds A having different anion structures in water droplets, and performing a bonding treatment using a polyvalent metal salt. (2) A method in which a solution of a polyvalent metal salt is dropped into a medium in which two or more types of raw material compounds A, each having a different anion structure, are dissolved, and precipitation or precipitating takes place while a bonding treatment is carried out; or a method in which a solution in which two or more types of raw material compounds A, each having a different anion structure, are dissolved, is dropped into a medium in which a polyvalent metal salt is dissolved, and precipitation or precipitating takes place while a bonding treatment is carried out (Method 2).

[0053] Method 1 is a method comprising the steps of forming a W / O emulsion containing two or more raw material compounds A with different anion structures in water droplets, and performing an ionic bonding treatment using a polyvalent metal salt.

[0054] An example of a method for forming a W / O emulsion will be described. First, a solution is prepared by dissolving two or more raw material compounds A, each having a different anion structure, in water or a mixed solvent of water and a hydrophilic organic solvent. Heating may be performed if necessary. Next, the solution is mixed with a hydrophobic organic solvent and emulsified using a stirrer, homogenizer, or the like. When mixing, the solution may be added to the hydrophobic organic solvent, or the hydrophobic organic solvent may be added to the solution. In this case, a surfactant or polymer stabilizer may be dissolved in the hydrophobic organic solvent and used to control the particle size of the water droplets in the W / O emulsion.

[0055] As another example of a method for forming a W / O emulsion, two or more types of raw material compound A, a hydrophobizing agent, water, a surfactant, a hydrophobic organic solvent, and other necessary components may be charged into a vessel all at once, and emulsified using a stirrer, homogenizer, or the like.

[0056] Heating may be performed when forming the W / O emulsion. Heating can increase the solubility, thereby homogenizing the raw material compound A and stabilizing the W / O emulsion. The heating temperature is preferably 15 to 100°C, and more preferably 40 to 80°C.

[0057] After forming the W / O emulsion, an ionic bonding treatment is carried out. The bonding treatment can be carried out by adding a solution containing a polyvalent metal salt to the W / O emulsion and stirring. Alternatively, the W / O emulsion can be added to a solution containing a polyvalent metal salt and stirred.

[0058] Examples of the polyvalent metal salt include calcium salt, strontium salt, magnesium salt, barium salt, radium salt, lead salt, zinc salt, nickel salt, iron salt, copper salt, cadmium salt, cobalt salt, and manganese salt, among which calcium salt and magnesium salt are preferred because they are metals contained in seawater and because of environmental, safety, and versatility considerations.Specific examples of the polyvalent metal salt include calcium chloride, calcium sulfate, calcium carbonate, calcium hydroxide, calcium oxide, magnesium chloride, magnesium sulfate, magnesium carbonate, magnesium hydroxide, and magnesium oxide, among which calcium chloride and magnesium chloride are preferred because of their solubility in water, ease of handling, cost, and the like.

[0059] The concentration of the polyvalent metal salt in the solution containing the polyvalent metal salt is preferably 1 to 40% by mass, more preferably 10 to 30% by mass. The solvent for the solution is preferably water, a lower alcohol solvent such as methanol, ethanol, 1-propanol, or 2-propanol, or a mixed solvent thereof, but a mixed solvent with other organic solvents may also be used as long as the salt can be dissolved to the desired concentration without dissolving the particles.

[0060] The bonding treatment may be carried out while heating as necessary. Heating may be carried out when adding the solution containing the polyvalent metal salt to the dispersion, or when stirring after the addition, or both. The heating temperature is preferably 10 to 100°C, and more preferably 40 to 80°C. The treatment time is preferably 0.5 to 24 hours, and more preferably 1 to 12 hours. Heating can increase the solubility of the hydrophobizing agent.

[0061] Since the aqueous phase of the W / O emulsion contains two or more types of raw material compound A and a hydrophobizing agent, the binding treatment also results in the hydrophobizing treatment being carried out at the same time.

[0062] After the bonding treatment, the particles can be washed and dried as needed to obtain particle groups made of the hydrophobic compound. Washing can be performed by a conventional method, for example, removing the solvent after the bonding treatment, adding water, and centrifuging. Drying can be performed by a conventional method, for example, spray drying, vacuum drying, freeze drying, etc. The obtained hydrophobic compound particle groups can be surface-treated or pulverized using known equipment to adjust the particle size, if needed.

[0063] Method 2 is a method in which a solution of a polyvalent metal salt is added dropwise to a medium in which two or more types of raw material compounds A having different anion structures are dissolved, and precipitation or precipitating takes place while a bonding treatment is carried out, or a method in which a solution in which two or more types of raw material compounds A having different anion structures are dissolved is added dropwise to a medium in which a polyvalent metal salt is dissolved, and precipitation or precipitating takes place while a bonding treatment is carried out.

[0064] An example of Method 2 will be described. First, a solution A is prepared by dissolving two or more raw material compounds A having different anion structures in water or a mixed solvent of water and a hydrophilic organic solvent. At this time, heating may be performed as necessary to improve solubility. Next, a solution B containing a polyvalent metal salt is added and stirred. Alternatively, a solution in which two or more raw material compounds A having different anion structures are dissolved may be added to a solution containing a polyvalent metal salt and stirred. The solution containing a polyvalent metal salt may be the same as that described in the explanation of Method 1.

[0065] By doing so, the bonding treatment can be carried out, and the target hydrophobic compound gradually becomes insoluble and precipitates or sediments. The treatment time is preferably 0.5 to 24 hours, and more preferably 1 to 12 hours.

[0066] At this time, a surfactant or a polymer stabilizer may be dissolved in at least one of solutions A and B in order to control the particle size of the precipitate or sediment.

[0067] Heating may be performed when precipitating or precipitating the target hydrophobic compound. Heating may be performed when mixing solution A and solution B, or when stirring after mixing, or both. Heating can increase the solubility of raw material compound A, thereby enabling polymerization by bonding and homogenizing the molecular weight distribution, and stabilizing the bonding. The heating temperature is preferably 15 to 100°C, and more preferably 40 to 80°C.

[0068] After the treatment, the particles can be washed and dried as needed to obtain hydrophobic compound particles. Washing can be performed by a conventional method, for example, removing the solvent after the binding treatment, adding water, and then centrifuging. Drying can be performed by a conventional method, for example, spray drying, vacuum drying, freeze drying, or the like. The obtained hydrophobic compound particle group may be subjected to a surface treatment or a pulverization treatment using known equipment to adjust the particle size, as needed.

[0069] [Resin composition] By using the marine biodegradation accelerator of the present invention in combination with a resin, particularly a biodegradable resin, a resin composition that promotes biodegradation in the ocean can be obtained. Furthermore, multiple types of resins can be used in combination to adjust the physical properties and handleability of the resin composition. Here, biodegradable resin means a resin that is decomposed by the action of microorganisms in nature and ultimately decomposed into inorganic substances such as water and carbon dioxide.

[0070] Resins that can be combined with the marine biodegradation accelerator of the present invention include polyethylene, polyester, polypropylene, polyethylene terephthalate, vinyl chloride, polystyrene, polyurethane, epoxy resin, chlorinated polyethylene resin, chlorinated polypropylene resin, modified nylon resin, phenolic resin, silicone resin, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, styrene-maleic acid resin, styrene-butadiene resin, butadiene resin, acrylonitrile-butadiene resin, poly(meth)acrylonitrile resin, (meth)acrylamide resin, bio-PET, bio-polyamide, bio-polycarbonate, bio-polyurethane, polyvinyl alcohol, polybutylene adipate / terephthalate, polyethylene terephthalate succinate, bio-polybutylene succinate, polylactic acid blends, starch blends, polyester resin, polybutylene terephthalate succinate, polylactic acid, polyhydroxyalkanoic acid, and the like. However, in consideration of reducing the burden on the environment, highly biodegradable resins are particularly preferred.

[0071] Examples of the biodegradable resin include polycaprolactone, poly(caprolactone / butylene succinate), polybutylene succinate (PBS), poly(butylene succinate / adipate) (PBSA), poly(butylene adipate / terephthalate) (PBAT), poly(butylene succinate / carbonate), polyethylene terephthalate copolymer, poly(ethylene terephthalate / succinate), and poly(tetramethylene adipate / terephthalate). Petroleum-derived resins such as polyethylene succinate, polyvinyl alcohol, polyglycolic acid, glycolic acid / caprolactone copolymer; (polylactic acid / polybutylene succinate-based) block copolymer, (polylactic acid / polycaprolactone) copolymer, (polylactic acid / polyether) copolymer, polylactic acid blend PBAT, lactic acid / glycolic acid copolymer, bio-polybutylene succinate, poly(butylene succinate / adipate), starch blend Resins partially derived from biomass, such as polyester resins and poly(butylene terephthalate succinate); resins 100% derived from biomass, such as polyhydroxyalkanoates (e.g., polyhydroxyalkanoates) (e.g., polyhydroxybutyrate / hydroxyhexanoate) (PHBH), poly(3-hydroxybutyrate / 4-hydroxybutyrate) (P3HB4HB), and poly(hydroxybutyrate / hydroxyvalerate) (PHBV), and polylactic acid (PLA); and resins derived from natural polymers, such as cellulose, cellulose acetate, cellulose ester resins, starch, esterified starch, and chitosan.

[0072] Among these, it is preferable to combine the marine biodegradation promoter with a biodegradable resin that is biodegradable in soil or compost but poorly biodegradable in the ocean, such as polycaprolactone, (bio)PBS, PBSA, PBAT, poly(tetramethylene adipate / terephthalate), poly(butylene succinate / carbonate), polyhydroxyalkanoates such as PHBH and PHBV, PLA, cellulose, starch, chitosan, and other resins derived from natural polymers. Resins derived from PBSA, PBS, PBAT, PLA, and starch are particularly preferred as the biodegradable resin.

[0073] Particularly preferred combinations of the marine biodegradation accelerator and biodegradable resin of the present invention include a marine biodegradation accelerator that contains at least one monovalent organic anion selected from laurate, myristate, palmitate, stearate, arachidonate, sarcosine derivative salts of lauric acid, myristic acid, or palmitic acid, and glutamic acid derivative salts of lauric acid, myristic acid, palmitic acid, or stearic acid, and is a divalent or higher ionic conjugate formed from two or more types of monovalent organic anions; and a biodegradable resin that is at least one selected from PBSA, PBS, PBAT, and starch-derived resins.

[0074] Furthermore, in consideration of reducing the environmental load, the raw materials for the resin to be combined are preferably biomass-derived, more preferably 25% or more of biomass-derived raw materials, even more preferably 50% or more of biomass-derived raw materials, and most preferably 80% or more of biomass-derived raw materials.

[0075] The resin composition of the present invention may contain a solvent. The solvent may dissolve the resin matrix while leaving the marine biodegradation promoter as particles, or may dissolve both the resin and the marine biodegradation promoter. By appropriately adjusting the solvent, the resin composition can be used as a molded body formed into a film by casting or the like, or as a paint, ink, surface treatment agent, etc. Preferred solvents include water, hexane, heptane, N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dimethyl sulfone, acetone, methyl ethyl ketone, diethyl ketone, acetophenone, dimethyl ether, dipropyl ether, tetrahydrofuran, chloroform, methylene chloride, trichloroethylene, ethylene dichloride, dichloroethane, tetrachloroethane, chlorobenzene, methanol, ethanol, n-propanol, isopropanol, butanol, pentanol, methyl glycol, methyl triglycol, hexyl glycol, phenyl glycol, ethylene glycol, propylene glycol, phenol, cresol, polyethylene glycol, benzene, toluene, xylene, etc. These may be used alone or in combination of two or more.

[0076] When a solvent is used, the total concentration of the resin and marine biodegradation promoter in the resin composition is preferably 0.5 to 90 mass%, more preferably 1 to 80 mass%, even more preferably 5 to 60 mass%, and most preferably 10 to 50 mass%. The ratio of the marine biodegradation promoter to the resin is preferably 99:1 to 10:90 by mass, more preferably 97:3 to 40:60, even more preferably 95:5 to 50:50, and most preferably 90:10 to 60:40.

[0077] The resin composition of the present invention may not contain a solvent. In this case, the resin may be heat-melted and then the insoluble marine biodegradation-accelerating agent may be added and mixed thereto, or the resin and the marine biodegradation-accelerating agent may both be melted and then mixed.

[0078] In the resin composition of the present invention, the content of the marine biodegradation promoter is 1 to 50% by mass, and the content of the resin is 50 to 99% by mass. However, to efficiently exert the effects of the marine biodegradation promoter of the present invention, the content of the marine biodegradation promoter is more preferably 3 to 50% by mass, even more preferably 5 to 45% by mass, even more preferably 7 to 40% by mass, and most preferably 10 to 35% by mass. On the other hand, the content of the resin is more preferably 50 to 97% by mass, even more preferably 55 to 95% by mass, even more preferably 40 to 93% by mass, and most preferably 65 to 90% by mass. By containing the marine biodegradation promoter in the above range, the resin can be used as a marine biodegradation promoter that promotes the progress of biodegradation in seawater while maintaining the physical properties of the biodegradable resin.

[0079] The resin composition of the present invention may contain additives, such as antioxidants, release agents, peeling agents, surface modifiers, hydrophobizing agents, water-repellent agents, hydrophilizing agents, dyes / pigments, colorants, heat stabilizers, light stabilizers, weather resistance improvers, antistatic agents, antifogging agents, lubricants, antiblocking agents, hardeners, softeners, compatibilizers, flame retardants, flow improvers, plasticizers, dispersants, antibacterial agents, fillers, metal deactivators, etc. The content of these additives is not particularly limited as long as it does not impair the effects of the present invention, but is preferably about 0.1 to 50 parts by mass per 100 parts by mass of the resin.

[0080] When the resin composition contains a solvent, it can be prepared, for example, by adding the resin, the marine biodegradation-accelerating agent, and, if necessary, the additives to a solvent simultaneously or in any order, and mixing them. When the resin composition does not contain a solvent, for example, the resin can be melted, and the marine biodegradation-accelerating agent and, if necessary, the additives can be added thereto simultaneously or in any order, and mixed; or the resin and the marine biodegradation-accelerating agent can be heated to melt and mix them together, and, if necessary, the additives can be added and mixed.

[0081] [Molded body] By molding the resin composition, a molded article can be obtained in which the marine biodegradation-accelerating agent is dispersed or dissolved in the resin. When the resin composition contains a solvent, the resin composition can be used as is for molding, and when the resin composition does not contain a solvent, the resin or the resin and the marine biodegradation-accelerating agent in the resin composition can be melted by heat and then molded.

[0082] The shape of the molded product may be, for example, a film, a fiber, a plate, a foam molded product, or any other shape depending on the intended use. The molding method is not particularly limited, and various conventionally known molding methods can be used. Specific examples thereof include blow molding, injection molding, extrusion molding, compression molding, melt extrusion molding, solution casting molding, and calendar molding. [Example]

[0083] The present invention will be described in more detail below with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited to the following Examples. In the following Examples and Comparative Examples, particle size distribution and volume average particle diameter (MV) were measured using a MICROTRACK MT3000 (manufactured by Microtrack Bell Co., Ltd.).

[0084] [Synthesis Example 1] Production of ethylene glycol monododecyl ether derivative A A 2,000 mL reaction vessel was charged with 240.0 g of ethylene glycol monododecyl ether, 63.1 g of succinic anhydride, 125.4 g of sodium carbonate, and 500.0 g of acetonitrile, and the mixture was stirred at 60°C for 4 hours. After stirring, the mixture was cooled to room temperature, and the precipitate was removed by filtration. The resulting filtrate was concentrated using an evaporator, and the solvent was removed under reduced pressure to produce ethylene glycol monododecyl ether derivative A, in which one end was substituted with -COONa.

[0085] [Synthesis Example 2] Production of Polycaprolactone Derivative B In a 3,000 mL reaction vessel, 186.3 g of 1-dodecanol was dissolved in 500 g of tetrahydrofuran, and 2.4 g of sodium hydride was added thereto and stirred for 1 hour at 0° C. Next, 342.4 g of ε-caprolactam was gradually added dropwise thereto, and the mixture was stirred at 0° C. for 4 hours, after which the temperature was raised to room temperature and stirring was continued overnight. Next, 100.0 g of succinic anhydride was added and stirred at 60°C for 4 hours. After stirring, the mixture was cooled to room temperature and the precipitate was removed by filtration. The filtrate was concentrated using an evaporator, and the solvent was removed under reduced pressure to produce polycaprolactone derivative B (Mn650) with one end substituted with -COONa.

[0086] [Example 1-1] Production of calcium (myristoyl sarcosine / stearate) particles (particles A1) The components shown below were charged into a 5,000 mL reaction vessel and dissolved at 70°C by stirring with a stirrer. 30% by mass sodium myristoyl sarcosinate aqueous solution 400.0g Sodium stearate 114.4g Ion-exchanged water 1,876.5g Ethanol 539.1g

[0087] Thereafter, 415.0 g of a 20.0 mass % calcium chloride aqueous solution was added dropwise while stirring to carry out a calcium substitution reaction, thereby precipitating particles. After stirring was completed, the mixture was repeatedly filtered and washed with ion-exchanged water, and the particles were dried to obtain the target particles A1. The particles A1 were observed with an SEM to confirm their shape, and were found to be scaly particles. The MV of the particles A1 was 88 μm.

[0088] [Example 1-2] Production of (sodium stearoyl glutamate / palmitate) calcium particles (particles A2) The components shown below were charged into a 5,000 mL reaction vessel and dissolved at 70°C by stirring with a stirrer. Sodium stearoyl glutamate 85.0g Potassium palmitate 57.4g Ion-exchanged water 3,417.6g

[0089] Thereafter, 216.7 g of a 20.0 mass % calcium chloride aqueous solution was added dropwise while stirring to carry out a calcium substitution reaction, resulting in the precipitation of particles. After stirring was completed, the mixture was repeatedly filtered and washed with ion-exchanged water, and the particles were dried to obtain the target particles A2. The particles A2 were observed with an SEM to confirm their shape, and were found to be scaly particles. The MV of the particles A2 was 116 μm.

[0090] [Example 1-3] Production of magnesium (dodecylbenzenesulfonate / myristate) particles (particles A3) The components shown below were charged into a 5,000 mL reaction vessel and dissolved at 60°C by stirring with a stirrer. Sodium dodecylbenzenesulfonate 120.0g Sodium myristate 86.2g Ion-exchanged water 1,855.8g

[0091] Thereafter, 437.9 g of a 20.0 mass % magnesium chloride aqueous solution was added dropwise while stirring to carry out a magnesium substitution reaction, thereby precipitating particles. After stirring was completed, the mixture was repeatedly filtered and washed with ion-exchanged water, and the particles were dried to obtain the target particles A3. The particles A3 were observed with an SEM to confirm their shape, and were found to be scaly particles. The MV of the particles A3 was 38 μm.

[0092] [Example 1-4] Production of (palmitic acid / myristoyl aspartic acid) aluminum particles (particles A4) The components shown below were charged into a 5,000 mL reaction vessel and dissolved at 50°C by stirring with a stirrer. Potassium palmitate 135.0g Potassium myristoyl aspartate 154.7g Ion-exchanged water 2,346.6g Ethanol 260.7g

[0093] Thereafter, 1361.0 g of a 10.0 mass % aluminum sulfate aqueous solution was added dropwise while stirring to carry out an aluminum substitution reaction, thereby precipitating particles. After stirring was completed, the mixture was repeatedly filtered and washed with ion-exchanged water, and the particles were dried to obtain the target particles A4. The particles A4 were observed by SEM to confirm their shape, and were found to be scaly particles. The MV of the particles A4 was 168 μm.

[0094] [Example 1-5] Production of (ethylene glycol monododecyl ether derivative A / palmitoyl sarcosine) calcium particles (particles A5) The components shown below were charged into a 3,000 mL reaction vessel and dissolved at 60°C by stirring with a stirrer. Ethylene glycol monododecyl ether derivative A 85.0g Sodium Palmitoyl Sarcosinate 83.3g Ion-exchanged water 1,060.3g Ethanol 454.4g

[0095] Thereafter, 264.9 g of a 20.0 mass % calcium chloride aqueous solution was added dropwise while stirring to carry out a calcium substitution reaction, thereby precipitating particles. After stirring was completed, the mixture was repeatedly filtered and washed with ion-exchanged water, and the particles were dried to obtain the target particles A5. The particles A5 were observed with an SEM to confirm their shape, and were found to be scaly particles. The MV of the particles A5 was 68 μm.

[0096] [Example 1-6] Production of (Polycaprolactone Derivative B / Myristoyl Sarcosine) Calcium Particles (Particles A6) The components shown below were charged into a 3,000 mL reaction vessel and dissolved at 60°C by stirring with a stirrer.

[0097] Polycaprolactone derivative B 125.0g Sodium Myristoyl Sarcosinate 114.6g Ion-exchanged water 766.7g Ethanol 191.7g

[0098] Thereafter, 396.0 g of a 20.0 mass % calcium chloride aqueous solution was added dropwise while stirring to carry out a calcium substitution reaction, resulting in the precipitation of particles. After stirring was completed, the mixture was repeatedly filtered and washed with ion-exchanged water, and the particles were dried to obtain the target particles A6. The particles A6 were observed by SEM to confirm their shape, and were found to be scaly particles. The MV of the particles A6 was 219 μm.

[0099] [Comparative Example 1-1] Production of polymethyl methacrylate (PMMA) particles (particles B1) The components shown below were all charged into a 2,000 mL flask, and a group of spherical polymer particles B1 made of PMMA alone and having an MV of 5 μm was prepared in the same manner as in Comparative Examples 1-3 of WO 2016 / 181877. Water 1,386.5g Methyl methacrylate 173.4g Lauryl peroxide 8.6g Polyvinylpyrrolidone (K-30) 17.3g

[0100] [Comparative Example 1-2] Production of polystyrene (PS) particles (particles B2) The compounds listed below were all charged into a 2,000 mL flask and a suspension was prepared using a Disper dispersion impeller at 1,000 rpm. The resulting suspension was stirred in an oil bath at 80°C under a nitrogen stream for 8 hours to obtain a PS particle dispersion. Water 1,280.0g Styrene 288.0g Lauryl peroxide 14.2g Polyvinylpyrrolidone (K-30) 21.6g

[0101] The resulting particle dispersion was transferred to a 3,000 mL flask and passed through a 200 μm sieve. The particle dispersion that passed through the sieve was then centrifuged, and this was repeated five times, followed by classification and washing, to obtain spherical polymer particles B2, which were pure PS and had an MV of 10 μm.

[0102] [Comparative Example 1-3] Production of Polybutylene Succinate (PBS) Particles (Particles B3) 30.0 g of biodegradable resin (PBS, Mitsubishi Chemical Corporation, FZ-91) pellets were frozen in liquid nitrogen and crushed in a crusher (Osaka Chemical Co., Ltd., Wonder Blender WB-1). The particle size was then adjusted using a sieve. This process was repeated to obtain a group of single PBS particles B3 with an MV of 10 μm.

[0103] [Comparative Example 1-4] Calcium alginate particles (particles B4) Calcium alginate spherical beads (Flavica Fine manufactured by Nisshinbo Chemical Inc., MV=20 μm) were used as particle group B4.

[0104] [3] Measurement of basic physical properties [Examples 2-1 to 2-6, Comparative Examples 2-1 to 2-4] The melting temperature and contact angle of each marine biodegradation accelerator were measured using the following methods. The results are shown in Table 1.

[0105] [Melt temperature measurement] Measurements were performed using a differential scanning calorimeter (DSC6200, manufactured by Seiko Instruments Inc.). Specifically, 10 mg of the sample was weighed out and placed in an aluminum pan. An empty aluminum pan was used as a reference. The sample was heated at room temperature and humidity within a measurement temperature range of 20 to 200°C at a heating rate of 10°C / min. The glass transition temperature (Tg) was calculated from the resulting reversing heat flow curve. The midpoint of the line connecting the intersections of the baseline and the endothermic curve was determined, and this was taken as Tg. The melting temperature was calculated from the endothermic (melting) peak of the resulting curve.

[0106] [Contact angle measurement] Each particle group was molded in a heat press set at a temperature equal to or higher than the melting point of the respective particle groups to produce a film with a thickness of 200 μm. Next, pure water was dropped onto the surface of the produced film in accordance with JIS R 3257, and the contact angle of the pure water was measured using a contact angle meter (Drop Master 300 manufactured by Kyowa Interface Science Co., Ltd.).

[0107] [Table 1]

[0108] [4] Solubility test [Examples 3-1 to 3-6, Comparative Examples 3-1 to 3-4] Each particle group was dispersed in water or an aqueous sodium chloride solution (sodium chloride concentration: 3% by mass) to a concentration of 0.1% by mass, and a solubility test was carried out. The results are shown in Table 2. (1) Appearance: The appearance was visually inspected 15 days after dispersion. (2) Shape: After dispersion in a sodium chloride aqueous solution, the change in shape after 15 days compared with the shape before the test was confirmed by particle size distribution measurement. (3) Transmittance: Each particle group was dispersed in a sodium chloride aqueous solution, and the transmittance of the dispersion at a wavelength of 560 nm after 15 days was defined as SD1 (%). Each particle group was dispersed in water, and the transmittance of the dispersion at a wavelength of 560 nm after 24 hours was defined as WD1 (%), and WD1 / SD1 was calculated. The transmittance was measured using a UV-visible spectrophotometer (UV-2450, manufactured by Shimadzu Corporation).

[0109] [Table 2]

[0110] [5] Solubility test 1 for resin molded products [Examples 4-1 to 4-6, Comparative Examples 4-1 to 4-5] Each particle group (particle groups A1 to A6, particle groups B1 to B5) was kneaded with biodegradable resin PBSA (FD-92 manufactured by Mitsubishi Chemical Corporation) at 140°C to a concentration of 20 by mass, and press-molded at 150°C to produce a film with a thickness of 150 μm (Examples 4-1 to 4-6, Comparative Examples 4-1 to 4-4). Also, PBSA itself (not containing particle groups) was press-molded at 150°C to produce a film with a thickness of 150 μm (Comparative Example 4-5). The presence or absence of each particle group in the film and the measurement results of the contact angle of the produced film are shown in Table 3. The presence or absence of particle shape was observed visually, and the contact angle was measured by the method described in "[3] Measurement of basic physical properties." The obtained films were cut into 10 mm squares and placed in 200 mL of ion-exchanged water and 200 mL of 3% by mass aqueous sodium chloride solution, respectively, and left to stand at 25°C for 15 and 45 days. After that, the films were removed and the surface and appearance of the films were observed using a scanning electron microscope. The results are shown in Table 3. SEM photographs of the film of Example 4-1 taken 45 days after immersion in water and 45 days after immersion in a 3 mass % aqueous sodium chloride solution are shown in Figures 1 and 2, respectively.

[0111] [Table 3]

[0112] [6] Solubility test 2 for resin molded products [Examples 5-1 to 5-6, Comparative Examples 5-1 to 5-5] Test films were prepared in the same manner as in "[5] Solubility test 1 for resin molded articles," except that the biodegradable resin was changed to PBS (FZ-91, manufactured by Mitsubishi Chemical Corporation) (Examples 5-1 to 5-6, Comparative Examples 5-1 to 5-4). For comparison, a resin film containing no particles was also prepared (Comparative Example 5-5). The presence or absence of each particle group in the film and the measurement results of the contact angle of the produced film are shown in Table 4. The presence or absence of particle shape was observed visually, and the contact angle was measured by the method described in "[3] Measurement of basic physical properties." The obtained films were cut into 10 mm squares and placed in 200 mL of ion-exchanged water and 200 mL of 3% by mass aqueous sodium chloride solution, respectively, and left to stand at 25°C for 15 and 45 days, after which the films were removed and the surface and appearance of the films were observed using a scanning electron microscope. The results are shown in Table 4. SEM photographs of the film of Example 5-2 taken 45 days after immersion in water and 45 days after immersion in a 3 mass % sodium chloride aqueous solution are shown in Figures 3 and 4, respectively.

[0113] [Table 4]

[0114] [7] Biodegradability test of powder [Examples 6-1 to 6-6, Comparative Examples 6-1 to 6-3] A seawater biodegradation test was carried out on particle groups A1 to A6 and particle groups B1 to B3 using the following method. As a control material, microcrystalline cellulose (Avicel PH-101 manufactured by Sigma-Aldrich) was used and evaluated based on the relative biodegradability of cellulose. The results are shown in Table 5.

[0115] <Test methods and conditions> Biodegradability measurement method: Measurement of oxygen consumption using a closed respirometer (reference ASTM D6691) Test equipment: OxiTop IDS (WTW) Incubation temperature: 30±1℃, dark place Biodegradation degree (%)=(BOD O -BOD B ) / ThOD×100 BOD O : Biochemical oxygen demand for testing or inoculum activity confirmation (measured value: mg) BOD B : Average biochemical oxygen demand of blank test (measured value: mg) ThOD: required when the test or control material is completely oxidized Theoretical oxygen demand (calculated value: mg) Relative biodegradability of cellulose (%) = (maximum biodegradability of test particles / maximum biodegradability of cellulose) x 100 Seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) The collected seawater was filtered to remove foreign matter using a 10 μm filter, and then aerated at room temperature of 25°C. In addition, inorganic nutrients such as ammonium chloride at 0.05 g / L and potassium dihydrogen phosphate at 0.1 g / L were added.

[0116] [Table 5]

[0117] The results shown in Table 5 indicate that particle groups A1 to A6 have biodegradability almost equivalent to that of cellulose up to a culture period of 56 days.

[0118] [8] Confirmation test 1 in seawater (weight loss) [Examples 7-1 to 7-20, Comparative Examples 7-1 to 7-6] Using particles A1, A2, A4, A6 and particles B1, the biodegradable resin PBSA (FD-92 manufactured by Mitsubishi Chemical Corporation) was added so that the amount of each particle group added was 3 mass%, 5 mass%, 10 mass%, 20 mass% and 30 mass%, respectively, and the mixture was kneaded at 140 ° C. and press-molded at 150 ° C. to produce a film with a thickness of 200 μm. In addition, PBSA itself (not containing particles) was press-molded at 150 ° C. as a blank to produce a film with a thickness of 200 μm (Comparative Example 7-6). The resulting film was cut into 20 mm square pieces, sandwiched between stainless steel nets, and immersed in seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) in a 40 L tank. The weight loss was observed after 30, 60, and 90 days. The results are shown in Table 6.

[0119] [Table 6]

[0120] From the results shown in Table 6, it is believed that biodegradability is promoted by the presence of microorganisms in seawater as well as by the breakdown caused by seawater.

[0121] [9] Confirmation test 2 in seawater (biodegradability test) [Examples 8-1 to 8-20, Comparative Examples 8-1 to 8-5] Each film obtained in "[8] Confirmation Test 1 in Seawater" was frozen in liquid nitrogen and then crushed using a crusher (Wonder Blender WB-1, manufactured by Osaka Chemical Co., Ltd.) and various crushed particles were prepared using a commercially available sieve so that the MV was 10 μm. A seawater biodegradation test was conducted for each of the crushed particles obtained using the following method. PBSA itself (not containing particles) was used as a blank, and the relative biodegradability to the blank was evaluated. The results are shown in Table 7.

[0122] <Test methods and conditions> Biodegradability measurement method: Measurement of oxygen consumption using a closed respirometer (reference ASTM D6691) Test equipment: OxiTop IDS (WTW) Incubation temperature: 30±1℃, dark place Biodegradation degree (%)=(BOD O -BOD B ) / ThOD×100 BOD O : Biochemical oxygen demand for testing or inoculum activity confirmation (measured value: mg) BOD B : Average biochemical oxygen demand of blank test (measured value: mg) ThOD: required when the test or control material is completely oxidized Theoretical oxygen demand (calculated value: mg) Relative biodegradability of cellulose (%) = (maximum biodegradability of test particles / maximum biodegradability of cellulose) x 100 Seawater (collected from Tokyo Bay [Chiba Prefecture: Chiba Port]) The collected seawater was filtered to remove foreign matter using a 10 μm filter, and then aerated at room temperature of 25°C. In addition, inorganic nutrients such as ammonium chloride at 0.05 g / L and potassium dihydrogen phosphate at 0.1 g / L were added.

[0123] [Table 7]

[0124] From the results shown in Table 7, it is considered that the marine biodegradation promoter of the present invention not only improves overall biodegradability but also has the effect of promoting the biodegradability of biodegradable resins in seawater.

[0125] These results indicate that the marine biodegradation accelerator of the present invention maintains its hydrophobicity in freshwater, while in seawater it becomes easily dissolved or hydrophilized by biodegradation, either through degradation into smaller molecules or salt substitution, prior to the biodegradability of biodegradable resins. Therefore, adding the marine biodegradation accelerator of the present invention to a resin composition biodegradable in soil / compost or a mixed composition with poor marine biodegradability can make the composition porous in seawater, promoting microbial adhesion and facilitating biodegradation. This ultimately improves overall marine biodegradability and reduces environmental impact. Furthermore, incorporating different organic anions into the structure can provide multiple benefits, including adjustment of melting temperature and melt viscosity, crystallinity, microbial adhesion and biodegradability, physical properties such as resin tensile strength, flexural strength, and elasticity, improved compatibility with resins, hydrophobicity, water repellency, adhesion, and plasticity, thereby improving both the biodegradability and physical properties of the mixed resin composition.

Claims

1. A marine biodegradation accelerator is a hydrophobic powder comprising a compound in which two or more monovalent organic anions having mutually different structures selected from monovalent organic anions derived from monovalent carboxylic acids, monovalent sulfonic acids, monovalent sulfate esters, and monovalent phosphate esters are bonded to a divalent or higher metal cation by ionic bonds, and the hydrophobic powder is soluble in a 3% by mass aqueous sodium chloride solution or exhibits hydrophilicity in a 3% by mass aqueous sodium chloride solution, at least one of the two or more organic anions has a monovalent hydrocarbon group having 6 to 30 carbon atoms; The marine biodegradation promoter, wherein the metal cation is a calcium ion, a magnesium ion, or an aluminum ion.

2. 2. The marine biodegradation promoter according to claim 1, wherein all of the two or more monovalent organic anions have a monovalent hydrocarbon group having 6 to 30 carbon atoms.

3. 3. The marine biodegradation accelerator according to claim 1, wherein the monovalent hydrocarbon group has 10 to 25 carbon atoms.

4. The marine biodegradation promoter according to any one of claims 1 to 3, wherein the monovalent organic anion is derived from a monocarboxylic acid.

5. 5. The marine biodegradation promoter according to claim 4, wherein the monocarboxylic acid is a fatty acid having a monovalent hydrocarbon group with 6 to 30 carbon atoms or an amino acid derivative having a monovalent hydrocarbon group with 6 to 30 carbon atoms.

6. 6. The marine biodegradation promoter according to claim 5, wherein the amino acid derivative is a sarcosinic acid derivative having a monovalent hydrocarbon group having 6 to 30 carbon atoms or a glutamic acid derivative having a monovalent hydrocarbon group having 6 to 30 carbon atoms.

7. The marine biodegradation promoter according to any one of claims 1 to 6, wherein the monovalent organic anion does not contain a ring structure.

8. The marine biodegradation promoter according to any one of claims 1 to 7, wherein the monovalent organic anion contains an amide group.

9. The marine biodegradation accelerator according to any one of claims 1 to 8, which is a compound having a molecular weight of 100 to 5,000.

10. The marine biodegradation accelerator according to any one of claims 1 to 9, which is in the form of a powder having an average particle size of 0.1 to 10,000 µm.

11. The marine biodegradation accelerator according to any one of claims 1 to 10, which is a thermoplastic powder.

12. The marine biodegradation accelerator according to claim 11, which is a thermoplastic powder having a melting temperature of 60 to 200°C.

13. The marine biodegradation accelerator according to any one of claims 1 to 12, wherein when a water droplet is dropped on a molten molded body of the particle group made of the powder, the contact angle after 30 seconds is 50° or more.

14. A marine biodegradable resin composition comprising the marine biodegradation accelerator according to any one of claims 1 to 13 and a resin.

15. The marine biodegradable resin composition according to claim 14, wherein the resin is a biodegradable resin.

16. The marine biodegradable resin composition according to claim 14 or 15, wherein the content of the marine biodegradation promoter is 3 to 50 mass% and the content of the resin is 50 to 97 mass%.

17. A molded article obtained from the marine biodegradable resin composition according to any one of claims 14 to 16.

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