JP7066252B2 - Fiber composite resin composition with sustained release of drug - Google Patents

Description

The present invention relates to a fiber composite resin composition having sustained release of chemicals, and in particular, a fiber carrying an insect repellent or insecticidal component, an aromatic or deodorant component, a pesticide or fertilizer component, and other drug components is used as a plastic. The present invention relates to a fiber composite resin composition having a sustained release property of a drug in order to realize a molded product having the sustained release property of these carried components and also having the required mechanical properties.

Materials that can gradually release insect repellent or insecticidal components, fragrance or deodorant components, pesticide or fertilizer components, and other chemical components over a long period of time, so-called sustained release materials, are known. As a specific sustained-release agent, one in which a drug component is supported on a porous substrate and one in which a drug component is dispersed in a degradable material are known.

For example, in Patent Document 1, a supercritical fluid having excellent diffusivity is used in the pores of a porous substrate, which is difficult or inefficient to support a drug component by impregnation with an organic solvent. It has been described that the drug component is efficiently supported in the pores of the substrate to sustain the release of the drug component.

Further, in Patent Document 2, the release rate of the drug component is controlled by dispersing the drug component in the improved degradable polymer.

Japanese Unexamined Patent Publication No. 2002-345940 Japanese Unexamined Patent Publication No. 4-173746

However, in the method of supporting the drug component in the pores of the porous substrate, the amount of the drug supported in the pores can be increased as described in Patent Document 1, but the pores in the substrate are the substrate. It has a structure that communicates to the surface, and the drug components are easily volatilized. For this reason, the range in which the duration during which the drug component can be released is not large, and it is necessary to use a drug with low volatility in order to sustain the release of the drug component over a long period of time such as several months or several years or more. , There are restrictions on the drugs that can be applied.

The method of dispersing the drug component in the decomposable material is to expose and volatilize the internally dispersed drug component by decomposing the decomposable material. Therefore, in order to control the release duration of the drug, there are restrictions on the type and amount of the degradable material. Furthermore, since the material itself disappears with the release of the drug, it cannot be applied to a member that requires strength with the release of the drug component, and its use is limited.

INDUSTRIAL APPLICABILITY The present invention solves the above-mentioned conventional problems, and has high controllability regarding release duration when various volatilizing drug components are released depending on the application, and high strength that can be applied to structural members. It is an object of the present invention to provide a fiber composite resin composition having sustained release property, which can be realized in combination with.

In order to achieve the above object, the fiber composite resin composition having sustained release property of the drug of the present invention is a fibrous filler of a resin and a cellulosic fiber contained in the resin in a dispersed state, and has a fiber length. It is characterized by containing a fibrous filler having a defibrated portion formed at the end in the direction and a volatilizing agent carried on the fibrous filler.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a fiber composite resin having controllability of release duration of a drug component required for a sustained release material and high strength applicable to a structural member.

Schematic cross-sectional view of the fiber composite resin composition according to the embodiment of the present invention. Schematic diagram of the fibrous filler in the embodiment of the present invention

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same components will be designated by the same reference numerals, and detailed description thereof will be omitted as appropriate.

(Embodiment)
FIG. 1 is a schematic cross-sectional view of the fiber composite resin composition according to the embodiment of the present invention.

As shown in FIG. 1, the fibrous composite resin composition of the present invention contains a resin 101, a fibrous filler 102, and a volatile agent 103. As shown in FIG. 2, the fibrous filler 102 has a defibrated portion 104 defibrated to a fiber diameter smaller than that of other portions at the end portion in the fiber length direction.

In the fibrous composite resin composition of the present invention, the volatile agent 103 present in contact with the fibrous filler 102 is present in the fibrous filler 102, or very fine pores between the fibrous filler 102 and the resin 101. Through, it reaches the surface of the molded body molded from the fiber composite resin composition, and the drug 103 is volatilized from the surface. The volatile agent 103 is not dispersed alone in the resin 101, but is supported on the fibrous filler 102.

In the present invention, the resin 101 is not particularly limited as long as it can disperse the fibrous filler 102 and is degradable and disappears. For example, polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, polyurethane, polytetrafluoroethylene, ABS resin, acrylic resin, polyamide, polyacetal, polycarbonate, modified polyphenylene ether, polyethylene terephthalate, polybutylene terephthalate, Thermoplastic resins such as cyclic polyolefins, polyphenylenzulfide, polysulfone, polyether sulfone, amorphous polyarylates, liquid crystal polymers, polyether ether ketones, thermoplastic polyimides, and polyamideimide can be used. Further, thermosetting resins such as phenol resin, epoxy resin, melamine resin, urea resin, unsaturated polyester resin, alkyd resin, polyurethane, and thermosetting polyimide can also be used. Furthermore, synthetic rubber and natural rubber such as isoprene rubber, butadiene rubber, styrene / butadiene rubber, chloroprene rubber, nitrile rubber, polyisobutylene, ethylenepropylene rubber, chlorosulfonated polyethylene, fluororubber, epichlorohydrin rubber, urethane rubber, and silicone rubber. Can also be used.

The fibrous filler 102 is dispersed in the resin 101 while carrying the volatile agent 103, and serves as a route for the volatile agent 103 when the volatile agent 103 is released to the outside, and also serves as a pathway for the volatile agent 103. It is used for the purpose of improving mechanical properties in a resin molded body molded by using the fiber composite resin of.

The fibrous filler 102 used for the above purpose is not particularly limited as long as it can support the volatile agent 103 and has a higher elastic modulus than the resin 101. For example, carbon fiber (carbon fiber), carbon nanotube, pulp, cellulose, cellulose nanofiber, lignocellulose, lignocellulose nanofiber, basic magnesium sulfate fiber (magnesium oxysulfate fiber), potassium titanate fiber, aluminum borate fiber, Examples thereof include calcium silicate fiber, calcium carbonate fiber, glass fiber, silicon carbide fiber, wallastnite, zonotrite, and various metal fibers. In addition, natural fibers such as cotton, silk, wool or linen, recycled fibers such as jute fiber, rayon or cupra, semi-synthetic fibers such as acetate and promix, polyester, polyacrylonitrile, polyamide, aramid and polyolefin. Synthetic fibers can be mentioned. Further, a modified fiber chemically modified on the surface of the synthetic fiber, a modified fiber chemically modified on the terminal of the polymer constituting the synthetic fiber, or the like can be used.

Dispersion for the purpose of improving the adhesiveness between the resin 101 and the fibrous filler 102, the dispersibility of the fibrous filler 102 in the resin 101, and the affinity between the fibrous filler 102 and the volatile agent 103. Additives such as agents may be used. In the present invention, the type of dispersant is not particularly limited. For example, various titanate-based coupling agents; silane coupling agents; unsaturated carboxylic acids or their anhydrides, maleic acid, modified polyolefins grafted with maleic anhydride; fatty acids; fatty acid metal salts; fatty acid esters and the like can be used. ..

As the volatile agent 103, insect repellent, insecticide, fragrance, deodorant, pesticide, fertilizer component and the like can be used depending on the purpose, and liquid or solid substances according to other purposes are used. be able to. That is, the type is not particularly limited as long as it can be supported on the fibrous filler.

For example, insect repellent and biorepellent agents include hinokithiol, saflor, limonen, linalol, menthol, 1,8-cineole, citral, eugenol, capsaicin, mint, vanillin, α-pinen, β-pinen, anetol, anis. Aldaldehyde, angelic acid, acetophenone, cinnamyl alcohol, green leaf alcohol, geraniol, naphthalin, diethyltoramide, lemongrass oil, lemongrass, synthetic musk, cinnamic aldehyde, pine oil, tarpineol, wood vinegar, acetoxyphenylbutane, hexanol, formic acid. Gerard, γ-lactone, angelica, cyclic terpene alcohol, N, N-diethyl-m-toramide, ethylometon, isothionate, cresol, vanilla, nonylraritan, linalol, 2-butoxyethanol, bisether, cyclohexane, isophorone, spearmint oil, Katsura alcohol, methylnonylketone, methylphenylketone, eucalyptus, allylisothianate, cycloheximide, hiba oil, peppermint oil, orange oil, lemon oil, mandarin oil, lime oil, sassafras oil, sage brain oil, cassia oil, linaroe Oil, peppermint oil, peppermint oil, pimento oil, bay oil, television oil, daiwikyo oil, anis oil, sage oil, sogo scent, pepper, peppermint, peppermint, sage, sage, vanilla, thyme, tanji, rosemary, sweet basil , Lemongrass, Hamanas, Bronze Fennel, Horse Radish, Bolizi, Dill, Meadow Sweet, Gluck Mallow, Rose Geranium, Lubarb, Italian Parsley, Bergamot, Wild Strawberry, Rocket Salad, Ginger Mint, Eau De Colon Mint, Peppermint, Cottage Pink, Moss curled parsley, salad burnet, chives, majorum, olives, curldon, pineapple sage, lemon thyme, purple basil, lemon balm, garden sage, roman camomile, sweet fennel, English lavender, lemon bergamot, heart seeds, hissop, pineapple mint, penny Extracts from herbs and spices such as royal, cleaning thyme, garden sage, wild leak, spearmint, bay, Greek oregano, ribwart, etc. Aroma or deodorant agents include, for example, natural fragrances such as lemon oil, lime oil, spearmint oil, jasmine oil, orange oil, pine oil, peppermint oil, eucalyptus oil, lavender oil, musk oil; or these fragrances. Examples thereof include synthetic fragrances made from limonene, linamol, eugenol, citranerol, vanillin, carboxylic, yonon, muscon, rose oxide, indole, geranyl acetate, ethyl benzoate and the like.

These agents, or one of the known agents that can be used for insect repellent, insecticidal, aromatic, deodorant, pesticide, fertilizer components, and other purposes, but not specifically exemplified, alone or in combination of two or more. Can be used.

The shape of the fibrous filler 102 will be described.

In the fiber composite resin composition of the present invention, the fibrous filler 102 carrying the volatile agent 103 is dispersed in the resin 101. Therefore, the volatile agent 103 moves from the inside to the surface of the molded product molded from the fiber composite resin composition through the contact points between the fibrous fillers 102, and the agent 103 is the molded product. Volatilizes from the surface. Therefore, if the fibrous filler 102 is composed of only those having a large fiber diameter, it is difficult to suppress the moving speed of the drug 103 inside the resin 101, and the release period of the drug 103 is shortened or volatilization. A large amount of the chemical 103 is required, which limits the mechanical properties of the composite resin. However, in the present invention, since the defibrated portion 104 in which the end portion of the fibrous filler 102 in the fiber length direction is finely defibrated is formed, the moving speed of the drug 103 in the defibrated portion 104 of the fibrous filler 102 is increased. It can be suppressed. Further, in the defibration portion 104, not only the fibers are thin but also the number of fine fibers is large, so that it is easy to come into contact with other adjacent fibrous fillers 102, and the agent 103 moves from the inside to the surface of the resin 101. A route is secured, and the internal drug 103 can be effectively volatilized without remaining. In order to realize a desirable moving speed of the drug 103 in such a fiber composite resin composition, it is desirable that the median fiber diameter at the defibration site 104 is 0.1 μm or more and 2 μm or less. If the median fiber diameter at the defibration site is as small as less than 0.1 μm, the moving speed of the drug 103 is significantly reduced, and it becomes difficult to develop the desired volatility of the drug 103. On the contrary, when the median fiber diameter at the defibration portion 104 is larger than 2 μm, the difference from the conventional fibrous filler in which the end portion is not defibrated becomes small, and it becomes difficult to release the drug 103 over a long period of time.

It is desirable that the median fiber diameter of the non-defibrated portion of the fibrous filler 102 is 5 μm or more and 30 μm or less. If the median fiber diameter in the non-defibrated portion is smaller than 5 μm, the amount of the volatile agent 103 that can be supported on the fibrous filler 102 becomes insufficient, and it becomes difficult to release the agent 103 over a long period of time. On the contrary, if the median fiber diameter in the non-defibrated portion is thicker than 30 μm, it is not preferable for ensuring high mechanical characteristics, which is one of the objects of the present invention, and specifically, the rigidity and impact resistance are lowered. Occurs.

The median fiber length of the fibrous filler 102 is preferably 5 μm or more and 2 mm or less. If the median fiber length is shorter than 5 μm, even if the defibrated portion 104 is formed at the end, the contact between the fibrous fillers 102 becomes insufficient, and the number of isolated fibrous fillers 102 inside the resin 101 increases. The drug 103 carried there cannot be effectively used. On the contrary, when the median fiber length is longer than 2 mm, many of the agents 103 are exposed on the surface of the resin 101 at the non-defibrated portion of the fibrous filler 102, so that the agent 103 volatilizes in a short period of time. The amount will be large.

The mixed volume ratio of the fibrous filler 102 and the resin 101 in the fiber composite resin composition is preferably (fibrous filler) :( resin) = 1: 99 to 70:30. When the ratio of the fibrous filler 102 is smaller than 1, the amount of the drug 103 that can be carried on the fibrous filler 102 and the contact between the fibrous filler 102 are insufficient, and the release performance of the drug, which is the object of the present invention, is deteriorated. The effect of improving mechanical properties, which is another purpose, is small, and for example, the elastic modulus can be expected to be improved by only 5% or less. On the contrary, when the ratio of the fibrous filler 102 is larger than 70, the contact between the fibrous fillers 102 becomes excessive, and many agents 103 move without passing through the defibrating portion 104 at the end of the fibrous filler 102. Therefore, it becomes difficult to release the drug 103 over a long period of time.

With the above-described configuration, the fiber composite resin composition of the present invention has a structure in which the fibrous filler 102 has a contact point and is dispersed in the resin 101, and also in the fibrous filler 102. Since the drug 103 is arranged and the volatile drug 103 is arranged in the very fine pores existing between the fibrous filler 102 and the resin 101, the drug 103 volatilizes to the outside and disappears. Even in the process of doing so, the dimensional change rate of the molded product using the fiber composite resin composition can be kept at −10% or more. Further, even if the volatile agent 103 disappears and, conversely, moisture or the like is adsorbed from the surrounding environment, the dimensional change rate of the molded product can be kept within 10%. Therefore, the molded body can be sufficiently used as a structure.

The method for producing the resin composition of the present invention is not particularly limited as long as the fiber composite resin composition can have the above-mentioned constitution. However, in order to form the defibrated portion 104 at the end of the fibrous filler 102 in the fiber length direction, which is a feature of the present invention, the undefibrated fibrous filler alone or a state in which the fibrous filler and the resin are mixed is used. Therefore, it is preferable to apply a strong shearing force to the fibrous filler. When the undefibrated fibrous filler is defibrated independently in advance, the fibrous filler can be dispersed in water or an organic solvent, and a high-pressure homogenizer, a bead mill, a refiner, or the like can be used. When defibrating a mixture of fibrous filler and resin, if the resin 101 is a thermoplastic resin or synthetic rubber, a melt kneading device such as a twin-screw kneading extruder, a twin-roll kneader, or a Banbury mixer may be used. can. If the resin 101 is a thermosetting resin, a kneading device for a viscous body such as a planetary mixer, a three-roll mill, or a ball mill can be used.

The method for supporting the volatile agent 103 on the fibrous filler 102 is also not particularly limited. However, as described above, it is preferable that the amount of the drug 103 present in contact with the fibrous filler 102 is larger than that present in the resin 101 alone. The drug 103 present alone in the resin 101, such as a method of mixing with the drug 103 and then mixing with the resin 101, or impregnating the fiber composite resin in which the fibrous filler 102 is dispersed in the resin 101 with the drug from the outside. It is preferable that the method can reduce the amount of

Hereinafter, examples and comparative examples of the present invention will be shown, but the present invention is not limited thereto.

In Examples 1 to 5 below, as shown in Table 1, the fiber diameter and fiber length of the fibrous filler and the mixed volume ratio of the fibrous filler and the resin were within the preferable ranges in the present invention. In Comparative Example 1, a conventional fibrous filler having no defibration site was used, and in Comparative Example 2, a polypropylene resin simple substance containing no fibrous filler was melt-kneaded with a volatile chemical.

In Examples 1 to 5, a fiber composite resin was prepared by the same procedure described below except for the fiber diameter and fiber length of the fibrous filler and the mixed volume ratio of the fibrous filler and the resin shown in the table below. As for Comparative Example 1, only the conditions of melt-kneading were different from those of Examples 1 to 5 as described below. Further, in all the examples and comparative examples, polypropylene manufactured by Prime Polymer Co., Ltd. (trade name J108M, elastic modulus 1.5 GPa) was used as the resin, and cotton-like coniferous pulp manufactured by Mitsubishi Paper Mills Limited was used as the fibrous filler. (Commercial name: NBKP Celgar) was used, and as the volatile agent, limonene, which is a room temperature liquid, which is a citrus-based aromatic component, was used. However, in Comparative Example 2, the fibrous filler is not used.

In the production of the fiber composite resin compositions in Examples 1 to 5 and Comparative Example 1, first, coniferous pulp was immersed in limonene and mixed by stirring with a planetary mixer. Then, excess limonene was removed to obtain limonene-moistened softwood pulp. In Examples 1 to 5, polypropylene was added to the softwood pulp and melt-kneaded at 180 ° C. with a twin-screw kneading extruder to prepare fiber composite resin pellets. Further, in Comparative Example 1, a kneading screw having a larger tip clearance and a smaller shearing action than the kneading screw of the twin-screw kneading extruder used in Examples 1 to 5 was used for melt-kneading at 200 ° C. , Fiber composite resin pellets were prepared.

Using each of the obtained fiber composite resin pellets, a plate-shaped molded body made of a fiber composite resin composition having a thickness of □ 100 mm and a thickness of 5 mm was produced by a flat plate hot press device. At the stage of melt-kneading in the process of the above treatment, the fact that defibration sites were formed at both ends of each fiber of the coniferous pulp of Examples 1 to 5 was observed after the melt-kneading of Examples 1 to 5 and Comparative Example 1. It was confirmed by observing the fibers obtained by dissolving and removing the resin from the resin pellets with a scanning electron microscope.

The elastic modulus of this plate-shaped molded product was measured with a tensile tester. Since improvement of mechanical properties is one of the effects of the present invention, the goal was to improve the elastic modulus of polypropylene alone by 10% or more with respect to 1.5 GPa.

In addition, an environment with a temperature of 60 ° C. was maintained by blowing from a box-type hot air dryer, and under that environment, the release duration until the aroma disappeared from the plate-shaped molded product made of the fiber composite resin composition was measured. .. The presence or absence of fragrance is measured by measuring the air near the surface of the plate-shaped molded body with an odor measuring device (OMU-Sn type manufactured by Futaba Electronics Co., Ltd.) equipped with a light odor sensor, and the time from the start of measurement until the odor intensity falls below 1000. Was defined as the release duration. The environment in which hot air having a temperature of 60 ° C. is blown is an accelerated test of about 50 times the volatilization of the drug in a normal atmosphere at room temperature. Therefore, when the goal is to maintain the aroma for one year or more in a normal atmosphere, the target release duration in this evaluation method is 168 hours or more.

Finally, the dimensional change rate was determined by measuring the dimensions between the marking lines previously placed at intervals of 50 mm on the surface of the plate-shaped molded body taken out from the dryer and cooled to room temperature.

The elastic modulus of the fiber composite resin composition obtained as described above, the dimensional change rate of the molded product before and after the release of the drug, and the release duration are shown in Table 1 below.

As is clear from the above results, in all of the fiber composite resins of Examples 1 to 5 of the present invention, the target drug release duration of 168 hours or more was obtained. Moreover, the elastic modulus was improved by 70% or more as compared with polypropylene alone. In particular, in Example 2 in which the shape of the defibrated portion of the fibrous filler was made appropriate and the mixing ratio of the fibrous filler to the resin was increased within the range of the present invention, an extremely long release duration and 4 of polypropylene alone were obtained. A high elastic modulus of twice was obtained.

On the other hand, in the fiber composite resins of Comparative Examples 1 and 2, which are outside the scope of the present invention, the target duration of drug release of 168 hours or more could not be obtained.

According to the present invention, the release sustainability of insect repellent or insecticidal components, aromatic or deodorant components, pesticide or fertilizer components, and other chemical components is accompanied by high strength applicable to structural members. It is possible to provide a fiber composite resin composition having sustained release of a drug.

101 Resin 102 Fibrous filler 103 Volatile chemicals 104 Defibering site

Claims (6)

The resin, the fibrous filler of the cellulosic fiber contained in the resin in a dispersed state, and the fibrous filler having the defibration portion formed at the end in the fiber length direction, and the fibrous filler were supported. A fiber composite resin composition having sustained release of a drug, which comprises a volatile drug. More of the volatilizing agents exist in the state of being supported by the fibrous filler than those existing alone in the resin, and the volatilizing agents are present on the surface or inside of the fibrous filler. The fiber composite resin composition having sustained release of the drug according to claim 1, wherein the fiber composite resin composition is released to the outside after moving through existing pores and reaching the surface of the fiber composite resin. 1. 2. A fiber composite resin composition having sustained release of the drug according to 2. The fiber composite resin composition having sustained release of the drug according to any one of claims 1 to 3, wherein the median fiber length of the fibrous filler is 5 μm or more and 2000 μm or less. Any of claims 1 to 4, wherein the mixed volume ratio of the fibrous filler and the resin in the fiber composite resin is (fibrous filler) :( resin) = 1: 99 to 70:30. A fiber composite resin composition having sustained release of the drug according to item 1. Light odor in an environment where the temperature is maintained at 60 ° C by blowing from a box-type hot air dryer in the process of gradually releasing and decreasing the volatilizing agent in the molded product molded from the fiber composite resin. When the air near the surface of the plate-shaped molded body is measured by an odor measuring device equipped with a sensor and the time from the start of measurement until the odor intensity falls below 1000 is defined as the release duration, the above-mentioned after the lapse of this release duration The fiber composite resin composition having sustained release of the drug according to any one of claims 1 to 5, wherein the dimensional change rate of the molded product with respect to immediately after molding is −10% or more and 10% or less.

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