JP2006087329A - Artificial seaweed bed - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly durable artificial seaweed bed made of synthetic fiber, tending to colonize microorganisms with good biological affinity, and also slight in environmental burden even after being disposed of. <P>SOLUTION: The artificial seaweed bed is characterized by that a microorganisms-colonizing carrier for seaweed or the like is constituted of modified polyvinyl alcohol resin-containing synthetic fiber. Specifically, the artificial seaweed bed is characterized by that such a carrier is constituted of modified polyvinyl alcohol resin-containing polylactic acid-based fiber. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an artificial seaweed basin that is installed in the sea, rivers, ponds, lakes, and the like and serves as a reef or contributes to purification of the water environment.

  A large number of seaweeds and algae are generally proliferated in the algae ground, and countless microorganisms settle in these, and small organisms that feed on these microorganisms naturally gather in the algae ground. When small fish that feed on small creatures gather, large fish that feed on small fish gather. Small creatures and large and small fish carcasses become nutrients for microorganisms. In this way, the seaweed basin provides a place for biochain.

However, in recent years, the seaweed beds have been declining due to various reasons, which poses a serious problem on the biological chain. So far, attempts have been made to optimize the biological chain by providing artificial algae beds and fishing reefs. Natural cellulose such as cotton, hemp, pulp, rayon, etc. A structure in which recycled cellulose is attached to a floating body (see, for example, Patent Document 1), synthetic resin, synthetic fiber, or natural fiber is formed into a string, thread, or belt of a predetermined length to lock a rope or net There are artificial seaweed beds such as structures attached to the body (see, for example, Patent Document 2), structures formed by binding, compressing, knitting or weaving carbon fiber filaments (for example, see Patent Document 3). Proposed.
JP-A-57-125624 Japanese Utility Model Publication No. 2-105346 Japanese Patent No. 3080567

  However, each conventional artificial seaweed has its own problems. First, those using natural fibers have a problem that they tend to rot and have poor durability. In addition, those using synthetic fibers have low biocompatibility and are inferior in terms of the effect of breeding algae and the like. Carbon fibers are considered to be a solution to this problem, but carbon fibers are stiff and inferior in flexibility, so weaving and cutting processes are easier than natural fibers and synthetic fibers. It is difficult, and the rocking property that shakes in water is low. Above all, carbon fiber is extremely expensive.

  In addition, when synthetic fibers are used, if left in large quantities, they become industrial waste, which may cause pollution problems, and there is also a problem that it is not preferable in the global environment. Those using carbon fiber are more difficult to dispose of because of their toughness.

  Therefore, the object of the present invention is to provide an artificial seaweed place made of synthetic fibers with excellent biocompatibility and easy to settle microorganisms and excellent in durability, and further provide an artificial seaweed place with a low environmental impact due to disposal. There is.

  In order to solve the above-mentioned problems, firstly, the present invention has a gist of an artificial algae field characterized in that a microorganism adhesion carrier such as algae is composed of a synthetic fiber containing a modified polyvinyl alcohol resin. Secondly, the gist of the artificial algae field is characterized in that a microorganism-adhering carrier such as algae is composed of a polylactic acid fiber containing a modified polyvinyl alcohol resin.

  The artificial seaweed bed according to the present invention, characterized in that the microorganism-adhering carrier such as algae is composed of synthetic fibers containing a modified polyvinyl alcohol resin, is made of synthetic fibers and has high biocompatibility, so A place where microorganisms such as algae are attached and settled easily, and because of the flexibility and flexibility unique to synthetic fibers, it swings like natural seaweeds and algae underwater and is preferred by small organisms and fish It is an artificial seaweed basin with excellent fish collection effect.

  In addition to the above-mentioned effects, the artificial seaweed bed characterized in that the microorganism-adhering carrier of the present invention, such as algae, is composed of a polylactic acid fiber containing a modified polyvinyl alcohol resin has biodegradability. In addition, it is easy to dispose of after use, and can be decomposed into harmless water and carbon dioxide by the action of microorganisms. At the same time, it can be manufactured without relying on petroleum resources, so it is also excellent in terms of protecting the global environment. It is an artificial seaweed bed.

  Hereinafter, the present invention will be described in detail.

  In the artificial algae field of the present invention, a microorganism-adhering carrier such as algae is composed of a synthetic fiber containing a modified polyvinyl alcohol resin. By containing the modified polyvinyl alcohol resin in the synthetic fiber, bioaffinity is improved due to the hydrophilicity derived from the hydroxyl group of the modified polyvinyl alcohol resin, and microorganisms such as algae are easily attached. As a result, microorganisms attract small organisms, small organisms attract small fish, and small fish attract large fish.

In the present invention, the synthetic fiber constituting the microorganism-adhering carrier is a synthetic fiber containing a modified polyvinyl alcohol resin. Such synthetic fibers can be formed from a composition containing a fiber-forming polymer as a main component and containing a modified polyvinyl alcohol resin. However, the fiber-forming polymer is not particularly limited, and is a polyamide. A known fiber-forming polymer such as polyester can be used.
In the present invention, the modified polyvinyl alcohol resin is preferably blended with a fiber-forming polymer. That is, it is preferable that the modified polyvinyl alcohol resin is mixed substantially uniformly with the fiber-forming polymer, rather than the layer comprising the modified polyvinyl alcohol resin being independently present in the composition forming the synthetic fiber. A synthetic fiber obtained by spinning a composition comprising such a blend is preferably used in the present invention. This prevents the modified polyvinyl alcohol resin from peeling off and eluting from the synthetic fiber.

And as content of the modified polyvinyl alcohol resin in the synthetic fiber containing modified polyvinyl alcohol resin, it is preferable to set it as 3-40 mass% of the mass of the said synthetic fiber, Furthermore, it is preferable to set it as 5-30 mass%. If it is less than 3% by mass, the bioaffinity as a microorganism-adhering carrier tends to be insufficient. On the other hand, if it exceeds 40% by mass, the spinning property is inferior, and the physical properties such as high elongation tend to decrease. It is not preferable.
As the modified polyvinyl alcohol resin used in the present invention, an oxyalkylene group-containing polyvinyl alcohol is preferable. Specifically, oxyalkylene group-containing polyvinyl alcohol is a copolymer of vinyl acetate and polyoxyalkylene (meth) allyl ether such as polyoxyethylene (meth) allyl ether, polyoxypropylene (meth) allyl ether, It is then obtained by saponification. In this case, the copolymerization ratio (content) of the polyoxyalkylene (meth) allyl ether is preferably 0.1 to 20 mol%, more preferably 0.1 to 5 mol%. The degree of condensation of the polyoxyalkylene is 1 to 300, preferably 3 to 50, and the proportion of oxyalkylene units in the entire oxyalkylene group-containing polyvinyl alcohol is preferably 3 to 40% by mass. This indicates that there is an optimum range for the degree of localization-delocalization of oxyalkylene units and the length of oxyalkylene units in the copolymer.
The saponification degree of vinyl acetate units in the oxyalkylene group-containing polyvinyl alcohol is preferably 50 to 100 mol%, more preferably 70 to 99 mol%, and the average polymerization degree of polyvinyl alcohol is preferably 150 to 1500, and more preferably 200 to 1000. In addition, components other than polyoxyalkylene (meth) allyl ether may be contained as a copolymerization component as long as the object of the present invention is not impaired. For example, α-olefin (ethylene, propylene, long chain α-olefin, etc.) , Ethylenically unsaturated carboxylic acid monomers (acrylate, methacrylate, acrylonitrile, methacrylonitrile, vinyl chloride, vinyl ether, etc.) may be contained as long as they are about 30 mol% or less.

  As the polymerization method for obtaining the oxyalkylene group-containing polyvinyl alcohol, a solution polymerization method is usually employed, and in some cases, a suspension polymerization method, an emulsion polymerization method, or the like can also be employed. As the saponification reaction, an alkali saponification method, an acid saponification method or the like is employed.

  In addition to the above, polyvinyl alcohol containing oxyalkylene group includes vinyl acetate, polyoxyethylene (meth) acrylate, polyoxypropylene (meth) acrylate, polyoxyethylene (meth) acrylamide, polyoxypropylene (meth) acrylamide, polyoxyethylene (1- (meth) acrylamide-1,1-dimethylpropyl) ester, polyoxyethylene vinyl ether, polyoxypropylene vinyl ether, polyoxyethylene allylamide, polyoxypropylene allylamide, polyoxyethylene vinylamide, polyoxypropylene vinylamide Etc. can be obtained by copolymerization and then saponification.

  In addition, the oxyalkylene group-containing polyvinyl alcohol can also be obtained by reaction of alkylene oxide with polyvinyl alcohol, or polymerization of vinyl acetate with polyoxyalkylene glycol and subsequent saponification.

The oxyalkylene group-containing polyvinyl alcohol thus obtained is further one of (1) a phenol compound having a melting point of 50 to 250 ° C., (2) a thioether compound, and (3) a phosphite compound. The above is preferably added in an amount of 0.01 to 5.0 mass%, particularly 0.1 to 0.5 mass% with respect to the oxyalkylene group-containing polyvinyl alcohol. Thereby, thermal stability can be improved. If the amount added is less than 0.01% by mass, improvement in thermal stability cannot be expected, and if it exceeds 5.0% by mass, the hydrophilicity and thus the biocompatibility tends to be reduced.

  Examples of the phenolic compound (1) having a melting point of 50 to 250 ° C. include 2,5-di-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 4,4′-thiobis- (6-t-butylphenol), 2,2'-methylene-bis (4-methyl-6-t-butylphenol), tetrakis- [methylene-3- (3 ', 5'-di-t-butyl-4' -Hydroxyphenylpropionate) methane, octadecyl-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate, 4,4'-thiobis- (6-t-butylphenol), N, N'-hexamethylene-bis (3,5-di-t-butyl-4'-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris (3,5-di -T-butyl-4- Droxybenzyl) benzene, pentaeryristyl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,1,3-tris (2-methyl-4-hydroxy-5) -T-butylphenyl) butane and the like.

  Examples of the thioether compound (2) include pentaerythritol-tetrakis- (β-laurylthiopropionate), tetrakis [methylene-3- (dodecylthio) propionate] methane, bis [2-methyl-4- {3- n-alkylthiopropionyloxy} -5-t-butylphenyl] sulfide and the like.

  Examples of the phosphite compound (3) include triphenyl phosphite, tris (p-nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, diphenylisooctyl phosphite, diphenyl Isodecyl phosphite, phenyl diisooctyl phosphite, phenyl diisodecyl phosphite, triisooctyl phosphite, tristearyl phosphite, other tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylene Examples thereof include phosphonite and di (2,4-di-t-butylphenyl) pentaerythritol diphosphite.

Furthermore, the oxyalkylene group-containing polyvinyl alcohol in the present invention includes (4) at least one of fatty acids having 10 or more carbon atoms or salts thereof, fatty acid amide compounds, and fatty acid ester compounds, and oxyalkylene group-containing polyvinyl alcohols. It is preferable to add 0.01 to 3.0% by mass, particularly 0.1 to 0.5% by mass, and the thermal stability is further improved.

  The fatty acid having a carbon number of 10 or more or the salt thereof in (4) above is a higher fatty acid such as lauric acid, palmitic acid, stearic acid, oleic acid, ricinoleic acid, arachidinic acid, behenic acid, erucic acid, or hydroxystearic acid, Examples thereof include hydroxy fatty acids such as hydroxyricinoleic acid, and metal salts such as magnesium, calcium, strontium, barium and zinc, among which stearic acid, magnesium stearate, calcium stearate and magnesium behenate are practical. The fatty acid amide compound (4) is a fatty acid amide such as stearic acid amide, palmitic acid amide, oleic acid amide, behenic acid amide, erucic acid amide, methylene bis stearic acid amide, ethylene bis stearic acid amide or the like. An alkylene bis fatty acid amide is mentioned. Furthermore, fatty acid ester compounds include fatty acid esters of monohydric alcohols such as butyl stearate and butyl palmitate, and fatty acid esters of polyhydric alcohols such as ethylene glycol monostearate.

  As a method of adding the compounds (1) to (4) to the oxyalkylene group-containing polyvinyl alcohol, a conventional method, that is, a melt can with a stirrer, an extruder, a roll kneader, etc. Pelletization is preferred. The melt mixing temperature is preferably 160 to 250 ° C, more preferably 180 to 230 ° C.

  Further, in the synthetic fiber containing the modified polyvinyl alcohol resin, various inorganic materials such as titanium oxide, silicon oxide, calcium carbonate, silicon nitride, clay, talc, and the like are included as long as the effects of the invention are not impaired. In addition to particles such as particles, cross-linked polymer particles, various metal particles, conventionally known stabilizers, antioxidants, antioxidants, anti-coloring agents, light-proofing agents, inclusion compounds, anti-static agents, coloring agents, surface activity Various additives such as an agent and a plasticizer may be blended.

  Furthermore, the synthetic fiber containing the modified polyvinyl alcohol resin may be a core-sheath type composite fiber. In this case, either the core part or the sheath part contains the modified polyvinyl alcohol resin, and the other core part. Alternatively, the sheath portion may not contain a modified polyvinyl alcohol resin.

  In the case where the core portion or the sheath portion of the composite fiber contains the modified polyvinyl alcohol resin, it is preferable that 3 to 50 mass% of the modified polyvinyl alcohol resin is contained in the mass of the core portion or the sheath portion. Further, the core / sheath composite ratio (mass ratio) is preferably core / sheath = 80/20 to 20/80. By making the modified polyvinyl alcohol resin content and core / sheath composite ratio in the core part or sheath part within the above-mentioned range, a composite fiber excellent in biocompatibility and having sufficient practicality such as yarn-making property and high elongation and the like can do.

  In the artificial algae ground of the present invention, it is a preferred aspect that the microorganism-adhering carrier is composed of a polylactic acid fiber containing a modified polyvinyl alcohol resin. That is, in the synthetic fiber containing the modified polyvinyl alcohol resin described above, a polylactic acid resin can be used as a fiber-forming polymer, thereby saving petroleum resources and having a biodegradable synthetic fiber. This is preferable in terms of protecting the global environment. Note that not only polylactic acid but also the modified polyvinyl alcohol resin described above has biodegradability, and the biodegradation rate of the modified polyvinyl alcohol resin is slightly slower than polylactic acid, but it is left in an environment where microorganisms exist. If it puts it, it can be set as the synthetic fiber which decomposes | disassembles completely after a fixed period.

  As the polylactic acid resin for obtaining the polylactic acid fiber, poly L-lactic acid, poly D-lactic acid, poly DL-lactic acid which is a copolymer of L-lactic acid and D-lactic acid, or a mixture thereof is suitable. The number average molecular weight is preferably from 30,000 to 150,000, and more preferably from 90,000 to 110,000. When the number average molecular weight is less than 30,000, not only fiberization by melt extrusion becomes difficult, but also the mechanical strength of the fiber tends to decrease. On the other hand, when the number average molecular weight exceeds 150,000, melt extrusion may be difficult.

  The polylactic acid resin in the present invention contains a small amount of a chain extender such as an organic peroxide, a bisoxazoline compound, a diisocyanate compound, an epoxy compound, and an acid anhydride for the purpose of increasing the molecular weight. Also good.

  Furthermore, in order to impart flexibility to the polylactic acid fiber, an aliphatic-aromatic copolymer polyester may be blended with polylactic acid. Polylactic acid has properties of being hard and brittle at room temperature, but it can be given flexibility by using it together with an aliphatic-aromatic copolymer polyester. At this time, by blending the aliphatic-aromatic copolymer polyester, considering the provision of flexibility and the decrease in strength, (polylactic acid) / (aliphatic-aromatic copolymer polyester) = 95 in mass ratio. It is preferable to blend at a ratio of / 6 to 50/50 (mass%). The aliphatic-aromatic copolymer polyester is a copolymer polyester having at least an aliphatic dicarboxylic acid, an aromatic dicarboxylic acid, and an aliphatic diol as constituent components, and its glass transition temperature is 0 ° C. or lower. Is preferable, and more preferably −20 ° C. or lower.

  Examples of the aliphatic dicarboxylic acid constituting such an aliphatic-aromatic copolymer polyester include succinic acid, adipic acid, suberic acid, sebacic acid, and dodecanedioic acid. Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and the like. Furthermore, examples of the aliphatic diol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol and the like. Then, by selecting and polycondensing at least one or more of these, the desired aliphatic-aromatic copolymer polyester can be obtained, and if necessary, isocyanate, acid anhydride, epoxy compound, organic peroxide The jump-up and long-chain branching can be given structurally using the above. In addition, a urethane bond, an amide bond, an ether bond, or the like may be introduced as long as the biodegradability is not affected.

In the artificial algae ground of the present invention, the microorganism-adhering carrier is constituted by a synthetic fiber (hereinafter sometimes abbreviated as a constituent fiber) containing the modified polyvinyl alcohol resin as described above. That is, the microorganism-adhering carrier is configured by binding, compressing, knitting, or weaving soft and flexible constituent fibers. The fineness and fiber length of the constituent fibers are not particularly limited, and may be appropriately adjusted as necessary.
As the microorganism-adhering carrier, it is preferable to use a constituent fiber that is formed into a predetermined shape that can be swung in water like natural seaweed. That is, the artificial seaweed bed of the present invention preferably includes an artificial seaweed molded from a synthetic fiber containing a modified polyvinyl alcohol resin.

  The specific form of the artificial algae field of the present invention is not particularly limited, and may be similar to that of a conventionally known artificial algae field. For example, as in the specific example disclosed in FIG. 1 of Japanese Patent No. 3080567, one end of an artificial seaweed composed of strands in which a large number of fibers having a diameter of 7 to 15 μm are bundled and bound at both ends is formed on the seabed. It is connected and supported by a string-like connecting member such as a rope supported by a fixed anchor bolt, and the other end is connected and supported by a pipe connected via a string-like connecting member such as a rope to the float, and artificial seaweed is spaced at a predetermined interval. It is possible to make an artificial seaweed bed having a structure arranged in a.

As the concrete form of the artificial seaweed, various kinds of the following (a) to (g) as disclosed in FIG. A form can be adopted.
(A) A braided strand molded body in which fibers are knitted to form a braid, and filaments are bulged at predetermined intervals in the longitudinal direction.
(B) A dendritic strand molded product in which a number of strands are branched from the fiber strand backbone.
(C) A broom-type strand molded body in which a plurality of fibers are connected and integrated into a fiber strand backbone.
(D) A lantern-shaped strand molded body in which a plurality of arc-shaped strands are formed in the middle of the fiber strand backbone.
(E) Akita Kanto type strand molded product in which fibers are connected and integrated to the strand backbone of the fiber at predetermined intervals in the longitudinal direction.
(F) A cord-like connecting member such as a rope is arranged at a predetermined interval, and fiber strands are twisted and connected and integrated so that the strands form a ring shape between the ropes.
(G) A net-like strand molded body in which fiber strands are knitted in a turtle shell shape.

  In the artificial seaweed having the above-described form, it is preferable that the filaments are separated from each other in the sea or underwater, and can swing like a seaweed according to the movement of the tide or flow. As a result, in the sea or water, the surface area of contact of the constituent fibers, which are microorganism-adhering carriers, with the microorganisms increases, so that the microorganisms are more likely to adhere to the constituent fibers, and the fixing speed and amount of microorganisms are improved.

Artificial seaweeds, such as those in which strands are compression-molded, coiled with strands, twisted yarns, and woven fabrics woven in various styles such as plain weave or satin weave It can be adopted as a form. The artificial seaweed is not limited to the above-described molded body as long as it is a molded body in which the constituent fibers can be scattered in the sea or in water and can be swung, and the contact surface area of the constituent fibers with microorganisms is increased. is not.

Claims (2)

  An artificial seaweed bed characterized in that a microorganism-adhering carrier such as algae is composed of a synthetic fiber containing a modified polyvinyl alcohol resin. An artificial alga bed characterized in that a microorganism-adhering carrier such as algae is composed of a polylactic acid fiber containing a modified polyvinyl alcohol resin.