JP4915867B2 - Composite material comprising interpenetrating network structure gel and predetermined adherent material, method for producing the same, and method for adhering interpenetrating network structure gel to predetermined adherent material - Google Patents

Description

  The present invention relates to a technique for bonding an interpenetrating network structure gel (IPN gel) excellent in mechanical strength and low friction characteristics to a predetermined adherend (for example, a hard material) with extremely high adhesive strength.

  An IPN gel, for example, a double network gel (DN gel) is a gel in which a first network structure and a second network structure exist in the gel. The gel is constructed by first constructing a first gel (single gel) related to the first network structure, and then allowing the monomer component related to the second network structure to penetrate into the gaps of the first network structure to polymerize and crosslink. (Patent Document 1).

  The IPN gel exhibits strong compression / tensile rupture stress, low coefficient of friction and chemical resistance, but also has flexibility as a gel, substance permeability, and impact resistance. Expected to be as diverse as water retention materials, industrial materials, and bio-substitution materials.

For example, the body joint part is covered with “cartilage” containing about 75% of water that serves as a cushion on the surface so that the bones do not collide with each other. When the function of the cartilage is impaired, metal or ceramic is used as an artificial bone on one side of the sliding portion of the artificial joint, and ultrahigh molecular weight polyethylene is used as the artificial cartilage on one side. Here, IPN which retains a large amount of moisture is expected as a new artificial cartilage material to replace ultra high molecular weight polyethylene because of its properties such as high strength, high impact absorbability and low friction coefficient.
WO2003 / 093337

  Here, the present inventors examined various known methods when adhering the IPN gel to a desired material. First, a method of adhering the IPN gel to the material using an adhesive can be considered. However, the IPN gel is a material that is difficult to adhere with an adhesive because it has a liquid surface (for example, water) and has a smooth surface. Furthermore, even if it can be temporarily bonded with an adhesive, if it is placed in an environment where various stresses (tensile stress, compressive stress, shear stress, etc.) are continuously applied, such as artificial cartilage as described above, There is a possibility that the adhesive durability cannot be maintained for a long time with the adhesive strength of the agent. Therefore, the next conceivable method is to select a raw material having a rough surface (for example, a porous material), apply a raw material monomer liquid on the rough surface, and directly form an IPN gel by polymerization and crosslinking after application. It is a technique to make it. According to this method, since the IPN gel is directly formed in a minute space (for example, pores) on the rough surface, a strong adhesive force due to the anchor effect is expected. However, the present inventors have confirmed that when trying to construct an IPN gel by this method, the following problems occur, and as a result, adhesion may not be possible. Specifically, when a hard material is used as a raw material, when a single gel, which is the previous stage of IPN, is constructed on a rough surface and then a monomer liquid is swollen in the single gel for IPN gel construction, While the single gel existing in the minute space on the surface is limited in expansion, the single gel existing outside the minute space can freely expand. Therefore, as a result of internal stress and strain occurring in the single gel, the gel is partially broken, such as cracking in the gel. Therefore, if the IPN gel is to be bonded by this method, it is not limited to bonding of a hard material but limited to bonding to a soft material such as a sponge that can expand to some extent even if a gel is formed inside. Further, regarding the soft material, even if no crack is generated, residual stress is generated due to the difference in gel strain inside and outside the soft material, and there is a possibility that the form and strength over the medium to long term cannot be maintained.

  Therefore, the present invention has a high strength enough to withstand even when placed in an environment in which various stresses (tensile stress, compressive stress, shear stress, etc.) are continuously applied, such as artificial cartilage, An object is to provide means capable of adhering to an adherend material (for example, a hard material).

The present invention (1) is a composite material comprising an interpenetrating network structure gel including a first network structure and a second network structure, and an adherent material having a rough surface formed on at least a part of the surface. And
The first network has a first part constructed on the rough surface of the adherend material and a second part mounted on the first part, which is separate from the first part. Have
The second network structure is constructed continuously across the gaps in the first part and the second part of the first network structure, and the interpenetrating network structure gel is directly on the rough surface of the adherend. Bonded composite material.

  The present invention (2) is the composite material of the invention (1), wherein the adherend material is a hard material.

  In the present invention (3), the adherend material is a porous material, and the interpenetrating network structure gel is constructed on the surface of the porous material and in the pores. It is a composite material.

  The present invention (4) is the composite material of the invention (2) or (3), wherein the hard material is ceramic or metal.

  In the present invention (5), the first network structure is a network structure having a charge, and the second network structure is electrically neutral or has a network structure having a smaller charge than the first network structure. A composite material according to any one of the inventions (1) to (4).

In the present invention (6), the first monomer solution (1) containing the first monomer component (1) is applied to the rough surface of the adherend, and then polymerization and crosslinking reaction are performed on the solution. A first step of constructing a first part of a network gel on the rough surface of the adherend,
A second step of obtaining a second part of the first network structure by carrying out polymerization and crosslinking reaction on the first monomer solution (2) including the first monomer solution (2);
A third step of introducing a second monomer solution (1) containing a second monomer component (1) into the first part of the first network structure;
A fourth step of introducing a second monomer solution (2) containing a second monomer component (2) into the second part of the first network structure, and the first step containing the second monomer solution (1). Polymerization and cross-linking reaction are performed on the second monomer solution (1) and the second monomer solution (2) in a state where the portion and the second portion containing the second monomer solution (2) are combined. A fifth step of continuously building a second network structure across both gaps in the first part and the second part of the first network structure,
Is a method for producing a composite material comprising an interpenetrating network structure gel and an adherend.

  The present invention (7) is the method of the invention (6), wherein the adherend material is a hard material.

  The present invention (8) is the method of the invention (6) or (7), wherein the adherend material is a porous material.

  This invention (9) is the method of the said invention (7) or (8) whose said hard material is ceramics or a metal.

  The present invention (10) includes the inventions (6) to (9), wherein the first monomer component is mainly composed of a charged monomer, and the second monomer component is composed mainly of an electrically neutral monomer. ) Is one of the methods.

In the present invention (11), the first monomer solution (1) containing the first monomer component (1) is applied to the rough surface of the adherend material, and then the polymerization and crosslinking reaction are performed on the solution. A first step of constructing a first part of a network gel on the rough surface of the adherend,
A second step of obtaining a second part of the first network structure by carrying out polymerization and crosslinking reaction on the first monomer solution (2) including the first monomer solution (2);
A third step of introducing a second monomer solution (1) containing a second monomer component (1) into the first part of the first network structure;
A fourth step of introducing a second monomer solution (2) containing a second monomer component (2) into the second part of the first network structure, and the first step containing the second monomer solution (1). Polymerization and cross-linking reaction are performed on the second monomer solution (1) and the second monomer solution (2) in a state where the portion and the second portion containing the second monomer solution (2) are combined. A fifth step of continuously building a second network structure across both gaps in the first part and the second part of the first network structure,
Is a method of adhering an interpenetrating network structure gel to a material to be adhered.

  The present invention (12) is the method of the above invention (11), wherein the adherend material is a hard material.

  The present invention (13) is the method according to the invention (11) or (12), wherein the adherend material is a porous material.

  The present invention (14) is the method according to the invention (12) or (13), wherein the hard material is ceramic or metal.

  The invention (15) is any one of the inventions (11) to (14), wherein the first monomer component has a monomer having a charge as a main component, and the second monomer component has a monomer having no charge as a main component. Is one way.

  Here, the definitions of terms in the claims and the specification will be described. First, the “first network structure” refers to a network structure formed before the second network structure is formed. Here, the “first part” and the “second part” of the first network structure are different in the network structure having the same composition (the raw material and the concentration thereof are the same) (types of raw materials such as raw material monomers and crosslinking agents and (Or, the concentration of the raw materials is different). The “second network structure” refers to a network structure formed after the first network structure is formed, and the same composition (raw material and its concentration) in the first part and the second part in the first network structure. May be a network structure consisting of different compositions (types of raw materials such as raw material monomers and crosslinking agents and / or different concentrations of the raw materials). Examples of the “rough surface” include a case where the surface roughness (Ra) is 0.5 μm or more, and a case where the hard material is porous (open pores, closed pores). “Adhesive material” refers to the material on the side where the interpenetrating network gel is joined, which constitutes the composite material, and includes both hard and soft materials, such as metals, ceramics, and plastics. Can do. “Hard material” refers to a solid material having an elastic modulus of 10 MPa or more. The “degree of crosslinking” refers to a value expressed as a percentage of the molar concentration of the crosslinking agent relative to the molar concentration of the charged monomer. In practice, there may be a slight amount of monomers that did not participate in the polymerization and a crosslinking agent that did not participate in the crosslinking. In this case, the degree of crosslinking of the gel in this specification is as described above. . The “interpenetrating network gel” is a concept including not only a so-called double network type but also a gel having a network structure of triple or quadruple or more.

  In the composite material according to the present invention (1), the IPN gel and the adherend are bonded with extremely high strength. Therefore, according to the present invention (1), even when various stresses (tensile stress, compressive stress, shear stress, etc.) such as artificial cartilage are continuously applied, the adhesion does not peel off, There is an effect that it is possible to continue to provide IPN characteristics (strong compression / tensile rupture stress, low friction coefficient, chemical resistance, flexibility, substance permeability, impact resistance, etc.) over a long period of time. In addition, in the IPN gel which comprises the said composite material, the 1st site | part in the 1st network structure and the 2nd site | part are divided | segmented in the 1st network in the interface, and both are joined by the 2nd network. Therefore, according to common general technical knowledge, the mechanical strength is weak at the interface, so that it is expected to break at the interface. However, in practice, it has been confirmed by experiments that the breaking strength is not particularly reduced even when compared with such an undivided IPN. This point is an unexpected effect from the technical common sense.

  According to the present invention (2), the first network structure is the first part despite the fact that the adherent material is a hard material and the gel easily breaks when the interpenetrating network structure gel is joined. Therefore, it is possible to provide a hard material / interpenetrating network structure composite material in which the gel is not broken.

  According to the present invention (3), since the adherent material is a porous material, the IPN gel penetrates deeper into the material and the invaded IPN gel is more difficult to come out. As a result, it is possible to provide a stronger adhesive force.

  According to the present invention (4), since the hard material is a general-purpose material that is used in various fields and is relatively easy to process, such as ceramics or metal, there is an effect that the application range of the composite material is expanded.

  According to the present invention (5), for example, in the form of a hydrogel, the first network is a tight and brittle network that is taut, and the second network is an easily stretchable network such as rubber (soft). Therefore, there is an effect that the IPN gel itself can be made extremely strong. Furthermore, the brittle first network swells (aqueous liquid medium such as water) or shrinks (oily liquid medium), while the soft second network has a degree of expansion and contraction due to the liquid medium compared to the brittle first network. Low. Here, when the IPN gel is placed in a predetermined environment, the expansion and contraction of the first part of the first network is limited by the hardness of the adherend material, while the expansion and contraction of the second part is relatively limited. I do not receive it. Thus, the situation where the degree of expansion and contraction of both differs is assumed. Even in such a case, since the first network is divided, the second site can be expanded and contracted independently of the first site, and the polymer constituting the second network is soft. Therefore, as a result of the expansion and contraction of the polymer corresponding to the expansion and contraction, it is possible to avoid the situation where the second network is cut at the interface due to the expansion and contraction.

  According to the method for producing a composite material according to the present invention (6) to (10), even if the first network structure is swollen with the second monomer liquid, the gel is not cracked (the adherend is a hard material). In addition, it is possible to produce a composite material in which the IPN gel and the adherend material are bonded with high strength without generating a high residual stress (when the adherend is a soft material).

  According to the method for producing a composite material according to the present invention (11) to (15), even if the first network structure is swollen with the second monomer liquid, the gel is not cracked (the adherend is a hard material). In this case, the IPN gel and the adherend material can be bonded with high strength without generating a high residual stress (when the adherend is a soft material).

<Overall composition of composite material>
The composite material according to the best mode is a composite material in which an IPN gel is directly bonded to a predetermined deposition material. Here, the IPN gel part of the composite material is formed on the first part, which is separate from the first part of the first network structure built on the rough surface of the adherend material and the first part. One feature is that it includes a second part of the first network structure that is mounted and a second network structure that is continuously constructed across the gap between the first part and the second part. That is, by having such a structure, the IPN gel is directly bonded to the adherend. Hereinafter, taking a hard material more suitable as an adherent material as an example, the composition and structure of the IPN gel and the hard material will be described first, and then the properties of the composite material will be described in detail.

<< Component 1 of composite material (IPN gel) >>
FIG. 1 is a conceptual diagram of a composite material according to the best mode. In addition, the said figure is a conceptual diagram to the last, and it should be understood that the thickness of a polymer, a crosslinking density, etc. do not reflect actuality. Therefore, the IPN gel will be described in detail with reference to FIG. 1. As described above, the first network structure (thin line in the figure) is originally in the first part 1 (1) and the second part 1 (2). It is divided. Here, the first part 1 (1) and the second part 1 (2) may have a network structure formed with exactly the same composition (raw material or concentration), or may have a network structure formed with different compositions. Good. Further, the second network structure (thick line in the figure) is particularly limited as long as it is continuously formed over the first part 1 (1) and the second part 1 (2) in the first network structure. First, the composition in the first part 1 (1) and the composition in the second part 1 (2) may be the same or different. This relates to the raw material liquid used when manufacturing the IPN gel, and the composition of the first part 1 (1) and the second part 1 (2) of the first network structure are different even if they are the same composition. Furthermore, in the second network structure, the raw material liquid introduced into the first part 1 (1) and the raw material liquid introduced into the second part 1 (2) have the same composition or different compositions. Means good. Further, the IPN gel may contain any liquid medium (generally also referred to as a solvent) inside (for example, water or an organic solvent), and may be a hydrogel or an organogel.

  Here, the network structure constituting the interpenetrating network structure is preferably a crosslinked body of an unsaturated monomer having a charge and / or an unsaturated monomer which is electrically neutral, or a crosslinked body of a natural polymer. Below, the unsaturated monomer which has a charge, the unsaturated monomer which is electrically neutral, and the natural polymer which are suitable raw materials for manufacturing the composite material which concerns on this best form are demonstrated first.

  As the unsaturated monomer having a charge, an unsaturated monomer having an acidic group (for example, a carboxyl group, a phosphoric acid group and a sulfonic acid group) or a basic group (for example, an amino group) is preferably used. Mention may be made of acrylamido-2-methylpropanesulfonic acid (AMPS), acrylic acid, methacrylic acid or their salts.

  Examples of electrically neutral unsaturated monomers include acrylamide (AAm), N-isopropylacrylamide, N, N-dimethyl-acrylamide, vinylpyridine, styrene, methyl methacrylate, fluorine-containing unsaturated monomers (for example, Fluoroethyl acrylate), hydroxyethyl acrylate or vinyl acetate.

  Examples of the natural polymer include bacterial cellulose and a charged natural polymer. Here, “bacterial cellulose” (hereinafter sometimes abbreviated as “BC”) means cellulose, heteropolysaccharide having cellulose as a main chain, β-1,3-, β-1,2, Or any mixture thereof. Constituent components other than cellulose in the case of heteropolysaccharides are hexoses such as mannose, fructose, galactose, xylose, arabinose, rhamnose, glucuronic acid, pentoses, organic acids and the like. Here, the microorganisms that produce bacterial cellulose are not particularly limited, but Gluconacetobacter xylinum subsp. Xylinum ATCC-53582 {Gluconacetobacter xylinus subsp. Xylinus (Yamada)}, Acetobacter aceti subsp. (Acetobactoracetisubsp xylinum), Pasteurian (A.pasteurium), Lancer (A.rancens), Sarcina ventriculi, Bacterium xyloides, Pseudomonas bacteria, Agrobacterium bacteria, etc. Those that produce cellulose can be used. The “natural polymer having a charge” refers to a protein or polysaccharide having a charge. Specific examples of the protein include gelatin and collagen, and examples of the polysaccharide include sodium alginate, gellan gum, carrageenan, chitosan, and hyaluronic acid. In addition, it also includes glycoproteins that are covalently bonded compounds of sugar and protein. Examples of such glycoproteins include proteoglycan and aggrecan.

  The crosslinking agent used when forming the first network structure or the second network structure is not particularly limited, and various types are selected according to the organic monomer to be crosslinked. For example, when AMPS, AAm, or AA is used as the organic monomer, N, N′-methylenebisacrylamide (MBAA) is used. When St is used as the organic monomer, ethylene glycol dimethacrylate is used. Can do.

  Here, as a combination of the first monomer component and the second monomer component, the former preferably selects a component that constitutes a hard and brittle gel when the gel is constructed alone, It is preferable to select components that constitute a soft gel when the gel is constructed alone. Specifically, the former preferably uses an unsaturated monomer having a charge which is a strong electrolyte such as 2-acrylamido-2-methylpropanesulfonic acid (AMPS), and the latter is electrically intermediate such as acrylamide. It is preferable to use an unsaturated monomer having a low charge or a monomer having a smaller amount of charge than the first monomer component (low dissociation constant). In the case of this preferred embodiment, the amount of the unsaturated monomer having a charge in the first monomer component is preferably 10 mol% or more, more preferably 30% or more, and more preferably Preferably it is 100 mol%. Further, the amount of the unsaturated monomer having no charge in the second monomer component is preferably 10 mol% or more, more preferably 50% or more, and even more preferably 100 mol% with respect to the second monomer component. is there.

  Further, the amount of the first monomer component in the IPN gel: the amount of the second monomer component is 1: 2 to 1: 100 (preferably 1: 3 to 1:50, more preferably 1: 3 to 1) in molar ratio. : 30). By adopting such a configuration, the IPN gel can be provided with characteristics such as unprecedented mechanical strength. Introduction of unsaturated monomers that are electrically neutral at such a high ratio results in a constant charge group (for example, sulfonic acid group, carboxyl group) by polymerizing and crosslinking the first monomer component. It becomes possible only by forming a network structure (first network structure) that is present in an amount or more and then introducing an unsaturated monomer that is electrically neutral. The amount of monomer in the gel is determined by elemental analysis when each network structure is composed of one type of monomer. In the case of two or more types, the elemental analysis may be complicated and cannot be determined. In such a case, for example, it is obtained by subtracting the amount of monomer that has not been polymerized from the amount of monomer used in the production.

  Furthermore, when the second monomer component is polymerized and crosslinked, it is preferable to set the degree of crosslinking smaller than when the first monomer component is polymerized and crosslinked. By adopting such a configuration, it is possible to impart characteristics such as unprecedented mechanical strength to the gel. Specifically, it is preferable that the degree of crosslinking of the first network structure is 0.1 to 50 mol%, and the degree of crosslinking of the second network structure is 0.001 to 20 mol%. More preferably, the degree of crosslinking of the structure is 1 to 20 mol%, the degree of crosslinking of the second network structure is 0.01 to 5 mol%, and the degree of crosslinking of the first network structure is 2 to 10 mol%. More preferably, the degree of cross-linking of the second network structure is 0.05 to 1 mol%. In order to reduce the water content of the gel (that is, reduce the degree of swelling) or harden the gel (that is, increase the elastic modulus), the degree of crosslinking of both may be increased.

<Component 2 of composite material (hard material)>
Subsequently, the hard material will be described in detail. The hard material is not particularly limited as long as it has a rough surface at least partially, and a hard material having a rough surface formed on the entire surface and a hard material having a rough surface formed only on the bonding portion with the IPN gel (for example, only the bonding portion) Any of the roughened material) may be used, and is not limited to one made of a single material, but a hard material made of a plurality of materials (for example, an adhesive portion with an IPN gel is a hard material layer, A composite material in which a soft material layer is further bonded to the hard material layer on the side opposite to the adhesive portion may be used.

  Here, the rough surface is not particularly limited as long as it has an anchor effect when the IPN gel is joined, but the surface roughness (Ra) is preferably 0.5 to 100 μm, It is more preferable that it is 1-20 micrometers.

  A particularly suitable hard material is a porous material. Here, the porous material is not particularly limited, and for example, porous ceramic, glass filter, porous ceramic material, porous sintered resin, porous particles, porous glass, pumice, foamed glass, porous mortar, porous Concrete, porous artificial stone, artificial bone, organic porous, isocyanate porous, porous metal, porous resin and the like. Although the size of the pore diameter of the porous material depends on the material to be used, 0.05 to 3000 μm is preferable, and 0.5 to 500 μm is more preferable. Here, generally, the smaller the hole diameter, the higher the adhesive strength. The reason is considered as follows. When the 1st site | part of the 1st gel is constructed | assembled in the hole and the 1st site | part of the said 1st gel swells with the 2nd monomer solution, the 1st site | part of the swollen 1st gel swells outside (projects). Then, it is understood that the bulge is formed like a dot on the entire surface of the first part. Here, it is considered that when the hole diameter is small, the bulge becomes small, whereas when the hole diameter is large, the bulge becomes large. And when mounting the second part on the first part of such a first gel, when the hole diameter is small, the first part and the second part are in good contact because the bulge is small, whereas the hole diameter If is too large, it is understood that the first part and the second part are in point contact. When the second network structure is constructed in this state where the first part and the second part are not sufficiently in contact (point contact state), the contact strength between the two parts is insufficient, so that the adhesive strength is lowered.

  Further, the porosity of the porous material is preferably 5% or more, and more preferably 30% or more. When the porosity is increased, the specific surface area in the porous material is increased, so that the adhesive strength can be further increased. In particular, even when the porosity is the same, the smaller the pore diameter, the larger the specific surface area. Therefore, when a higher adhesive strength is required, it is preferable to select a porous material having a high porosity and a small pore diameter. It is.

  As described above, the components of the IPN gel and the hard material (especially the porous material) have been described in detail. By changing the pore size of the porous material, the polymer component introduced into the pore and the degree of crosslinking, the porous material and It is thought that the adhesive strength of the IPN gel can be controlled (this will be described in detail below).

<Properties of composite materials>
(Strong adhesion)
The property of the composite material according to the best mode is a very strong adhesive force between the IPN gel and the hard material. The first network structure is divided into a first part and a second part, and the respective networks are not directly bonded. Therefore, when an attempt is made to peel off the IPN gel from the hard material, it is usually expected that the IPN gel is cut at the interface between the first part and the second part of the first network structure. However, contrary to the expectation, when an attempt is made to peel off the IPN gel from the hard material, the IPN itself breaks first rather than being cut at the interface between the first part and the second part of the first network structure. It was confirmed that. The IPN gel and the hard material are joined with such a strong adhesive force. Specifically, the breaking energy of the bonding surface of the composite material according to the best mode, 20 J / ^{m 2} or more is preferred, 100 J / ^{m 2} or more is more preferred, 900 J / ^{m 2} or more is more preferred is there.

Here, the factors that determine the adhesive force between the hard material and the IPN gel include the above-mentioned “surface roughness of the hard material”, and “the pore diameter” and “porosity” when the hard material is a porous material. , “Adhesion based on interaction between hard material and IPN gel”. Examples of the interaction (intermolecular interaction) include electrostatic interaction, hydrogen bond, dipole-dipole interaction, hydrophobic interaction, and the like. For example, when a porous glass filter is used as the hard material, glass (SiO ₂ -based) has positive ions on the surface when the pH is lowered to 3 or less. For such a hard material, an acidic PAMPS network is constructed as the first network, and an electrically neutral PAAm network is constructed as the second network. As a result, the positive ions formed on the glass surface and the negative ions (sulfonic acid group) of PAMPS attract each other, so that the glass and the PAMPS / PAAm gel are more strongly bonded (charge attraction action). On the other hand, when the non-acidic PNaAMPS / PAAm (DN) gel is used instead of the charged PAMPS / PAAm gel, the adhesive strength is relatively lowered.

<< Production Method of Composite Material (Method of Adhering IPN Gel to Hard Material) >>
A method for producing a composite material of a hard material and an IPN gel according to the present invention (a method of bonding an IPN gel to a hard material)
After applying the first monomer solution (1) containing the first monomer component (1) to the rough surface of the hard material, the solution is subjected to polymerization and cross-linking reaction, whereby the first part of the first network gel A first step of constructing on the rough surface of the hard material,
A second step of obtaining a second part of the first network structure by carrying out polymerization and crosslinking reaction on the first monomer solution (2) containing the first monomer component (2);
A third step of introducing a second monomer solution (1) containing a second monomer component (1) into the first part of the first network structure;
A fourth step of introducing a second monomer solution (2) containing a second monomer component (2) into the second part of the first network structure, and the first step containing the second monomer solution (1). Polymerization and cross-linking reaction are performed on the second monomer solution (1) and the second monomer solution (2) in a state where the portion and the second portion containing the second monomer solution (2) are combined. A fifth step of continuously building a second network structure across both gaps in the first part and the second part of the first network structure,
Is essential. Hereinafter, each process is explained in full detail.

  First, the 1st process which concerns on the said method is a process of constructing | assembling the 1st site | part of a 1st network structure on the hard material surface. The first monomer solution (1) used in the first step typically contains the first monomer (1) and the first crosslinking agent (1) {optionally the first polymerization initiator (1)}. . Here, in order to sufficiently adhere the first monomer solution (1) to the rough surface of the hard material, as a device on the hard material side, prior to application of the monomer solution, wetting with the first monomer solution (1) The surface of the hard material is subjected to a surface treatment for improving the properties, and as a process device, for example, the first monomer solution (1) is applied while pressure is applied, and the hard material is porous. In the case of a material, the first monomer solution (1) can be sucked into the porous material while reducing the pressure from the side opposite to the application surface of the first monomer solution (1).

  In addition, processes not characteristic of the present invention, such as a polymerization reaction and a crosslinking reaction, can be performed according to a well-known method. For example, the polymerization reaction may be any method such as thermal polymerization or photopolymerization. And as a polymerization initiator to be used, a various thing is selected corresponding to the organic monomer which should superpose | polymerize. For example, when thermally polymerizing AMPS, AAm, AA as an organic monomer, a water-soluble thermal initiator such as potassium persulfate (KPS), a redox initiator such as potassium persulfate-sodium thiosulfate can be used, In the case of photopolymerization, 2-oxoglutaric acid can be used as a photosensitizer. When St is thermally polymerized as an organic monomer, a thermal initiator soluble in an organic solvent such as azobisisobutyronitrile (AIBN) or benzoyl peroxide (BPO) can be used for photopolymerization. In some cases, benzophenone can be used as a photosensitizer.

  Next, the second step is a step of obtaining a second part of the first network structure, but the network structure constituting the second part can be separately synthesized by a known method. Here, the first monomer solution (2) used may have the same composition as or different from the first monomer solution (1) as described above. Typically, the first monomer solution (2) and the first monomer solution (1) A crosslinking agent (2) {optionally contains a first polymerization initiator (2)}.

  Next, in the third step, after preparing the second monomer solution (1) containing the second monomer component (1), the second monomer solution (1) is placed in the first part of the first network structure. Introduce. Here, the second monomer solution (1) used typically contains the second monomer (1) and the second crosslinking agent (1) {optionally the second polymerization initiator (1)}. The introduction method is not particularly limited, and examples thereof include a method of immersing the hard material in which the single network gel relating to the first part is formed in the second monomer solution (1). Here, the radius of the monomer molecule to be introduced is preferably 100 nm or less, and more preferably 10 nm or less.

  Next, in the fourth step, after preparing the second monomer solution (2) containing the second monomer component (2), the second monomer solution (2) is placed in the second part of the first network structure. Introduce. Here, the second monomer solution (2) used may have the same composition as or different from the second monomer solution (1) as described above. It contains a crosslinking agent (1) {second polymerization initiator (1) in some cases}. The introduction method is not particularly limited, and examples thereof include a method of immersing the single network gel relating to the second part in the second monomer solution (1). Here, the radius of the monomer molecule to be introduced is preferably 100 nm or less, and more preferably 10 nm or less.

  If the second monomer solution (1) used in the third step and the second monomer solution (2) used in the fourth step are the same, the third step and the fourth step may be performed simultaneously. Good. In this case, the method of immersing both the hard material in which the single network gel which concerns on a 1st site | part was formed, and the single network gel which concerns on a 2nd site | part to a 2nd monomer solution is mentioned.

  Next, in the fifth step, polymerization and crosslinking reaction are carried out in a state where the first part and the second part of the first network structure are in contact (attached). At this time, if there is a gap between the first part and the second part, the strength at the interface between the first part and the second part in the composite material after manufacture is weakened, so that a firmly attached state is ensured. This is very important. For example, pressure is applied so as to sandwich the first part and the second part. The pressure at that time is preferably about the same as the elastic modulus of the softer one of the first part and the second part.

  As for the solvent used in this step, the hard material surface immersed in the solution and the adverse effect on the first network structure built on the surface are prevented, and the double network structure is changed to the first network structure. From the viewpoint of good entanglement with the network, it is preferable that the solvent of this solution is the same as the solvent in the gel having the first network structure. In addition, regarding the liquid medium (solvent) finally contained in the IPN gel of the composite material, the liquid medium may be used from the manufacturing stage, or liquid medium exchange (solvent exchange) may be performed after the production.

<Application>
The composite material according to the present invention can be swollen with a solvent such as water and used as a hydrogel. A composite material of a hard material and an IPN gel can be expected to exhibit unique properties, and its application fields are also wide. In particular, it can be used for biomaterials such as artificial joint cartilage. In this case, by using a hard inorganic material such as ceramic or metal as the hard material and fixing the hard inorganic material to the bone, the IPN gel can be fixed to the bone via the hard inorganic material.

<Adhesive material>
Regarding the hard material, the deposition material used in this example is a glass filter (P-5, P-16, P-40, P-100, P-160, P-250), a porous ceramic material (architectural field). And soft materials are sponge (white) (melamine foam sponge sponge) and sponge (yellow) (three-layer sponge for kitchen) (FIG. 2). SEM photographs of the surface of each substance are shown in FIGS. According to the SEM photograph, the pore size of the glass filter P-5 is 4 to 5.5 μm, P-16 is 10 to 16 μm, P-40 is 16 to 40 μm, P-100 is 40 to 100 μm, and P-160 is 100 to 160 μm. , P-250 was 160 to 250 μm, and sponge (white) was about 30 to 50 μm. The measurement data of the surface roughness of the glass filters (P-5, P-16, P-40, P-100, P-160, P-250) are shown in FIG. Ra of P-5 was 1.21 μm. The measurement data of the surface roughness of the porous ceramic material is shown in FIG. The porous ceramic material was 0.9 μm. The porosity of P-5 was 64%, the porosity of P-16 and P-40 was 50% or more, and the porosity of P-100, P-160 and P-250 was about 30% (FIG. 8). . The glass filters P-5, P-16, P-40, P-100, P-160 and P-250 were 40 mm in diameter and 4 mm in thickness. The three-layer sponge for kitchen has three layers, the uppermost layer is made of nylon and polyester, the middle layer is made of orange oil cleanser, and it is observed that there is a network structure. Is dense and made of polyethylene.

"Measuring method"
The surface roughness means arithmetic average roughness (Ra), and is measured by a method defined in JIS B0601.

  The average value of the pores (diameter) is measured by SEM photographs (average of 100).

The porosity is calculated by the following formula.
Porosity = V _hole / V _total = (V _total− V _grains ) / V _total × 100%
Volume of porous material ( _total V) = volume of particles (V _grains ) + volume of pores (V _holes )
Moreover, the measurement of V _particle | _grains is the difference of the total volume of the sample in which the sample was immersed in water, the sample in which the said sample was immersed, and the total volume of water before sample immersion. In determining the volume difference, the water used is measured after vacuum degassing.

The fracture energy of the adhesive surface is determined by fixing the adherent material adhered to the IPN gel on the glass with an adhesive and cutting it in parallel from the surface of the gel to the surface of the adherend with a cutter knife at a distance of 5 cm. As shown in FIG. 9, a tensile test was performed to measure the adhesive strength. The fracture energy (G) was calculated by the following formula.
G = W / ΔS = FΔI / dΔI

<Production method of composite material>
Degassing treatment that immerses the adhering material in a mixed solution of AMPS (AMPS 1M, crosslinker MBAA 4 mol%, initiator KPS 0.1 mol%), and performs vacuum degassing with a pump for 2 hours to expel air from the adhering material. And soaked for 3 days. Thereafter, the adherend was sealed in a glass substrate, and thermal polymerization was performed in a water bath at 60 ° C. for 10 hours. As a result, an adherend material in which the first part (PAMPS) of the first network structure was constructed on the surface was obtained. Next, a PAMPS gel (AMPS 1M, crosslinker MBAA 4 mol%, initiator KPS 0.1 mol%) as the second part of the first network and the adherend material on which the first part is constructed are AAm. (Second monomer solution; AAm 2M; MBAA 0.01 mol%; KPS 0.1 mol%), vacuum defoaming was performed with a pump for 2 hours, and immersion was performed for 3 days. Then, after putting these in an Ar atmosphere glove box and degassing (3 hours), enclosing them in a state of sandwiching both in a glass substrate and putting them in a bag, taking them out of the glove box, Thermal polymerization was performed in 10 hours. Then, it was immersed in pure aqueous solution for one week, and water was replaced. FIG. 10 shows an outline of the bonding process according to the method (in the case of a glass filter).

Example 1
A glass filter (P-5, P-16, P-40, P-100, P-160, P-250) was subjected to an adhesion experiment according to the procedure of the above manufacturing method. The adhesive strength before and after the obtained composite was swollen with pure water was measured. FIG. 11 is a diagram showing values of fracture energy between the six types of bonded glass filters and the IPN gel. As can be seen from the figure, the adhesive strength was extremely high before and after swelling. In addition, it was confirmed that the adhesive strength before swelling tends to be stronger than the adhesive strength after swelling. This is thought to be due to the fact that stress is generated between the gels filled in the glass filter due to the swelling of the IPN gel, and it is easy to break. Moreover, the adhesive strength between the P-5 filter and the IPN gel was the highest. The results suggested that the adhesion between the filter and the IPN gel can be controlled by the pore size.

Example 2
Using a P-5 glass filter, an adhesion experiment was performed by changing the amount of the cross-linking agent MBAA in the mixed solution of AAm as the second monomer component. In addition, except for the said conditions, the adhesion experiment was conducted under the same conditions as those of << Production method of composite material >>. The measured adhesive strength is shown in FIG. As clearly shown in the figure, the interface between the glass filter and the IPN gel was not broken, but the IPN gel itself was broken. That is, it is considered that the adhesive strength between the glass filter and the IPN gel is stronger than the breaking strength of the IPN gel itself.

Example 3
According to << Production method of composite material >>, using glass filter (P-5), the concentration of the crosslinking agent MBAA used in the first part of the first network structure is changed to 1, 2, 4, 8, 10 mol%. An adhesion experiment was conducted. The composition of the other AMPS mixed solution was AMPS 1M: KPS 0.1 mol%. The composition of the PAMPS gel corresponding to the second part of the first network structure was AMPS 1M, crosslinker MBAA 4 mol%, and initiator KPS 0.1 mol%. Moreover, the composition of the mixed solution of AAm was set to AAm 2M: MBAA 0.01 mol%: KPS 0.1 mol%, and the experiment was conducted. The results are shown in FIG. FIG. 13 shows the value of the breaking energy between the bonded filter (P-5) and the IPN gel. As the concentration of the crosslinked MBAA in the first part of the first network structure increased, the adhesive strength increased. That is, it was found that the adhesive strength between the filter (P-5) and the IPN gel was highest when the concentration of the crosslinked MBAA in the first part of the first network structure was 10 mol%.

Example 4
An experiment was conducted in accordance with the conditions of Example 1 above using a porous ceramic material as a hard material other than the glass filter. As a result of measuring the adhesive strength, it was 37.7 J / m ² (FIG. 14). Further, two types of sponges were used as the soft material, and experiments were conducted according to the conditions of Example 1 above. As a result of measuring the adhesive strength, all were over 200 J / m ² (FIG. 14). As for the sponge (white), when immersed in the AAm solution, the PAMPS sponge swelled about 3 times, and the internal sponge structure was partially destroyed (residual in the PAMPS gel as white particles). As for the sponge (yellow), since the lower layer sponge is composed of hydrophobic polyethylene, the solution did not enter the polyethylene and no gel was constructed.

  The composite material and the composite material manufacturing method according to the present invention overcomes the disadvantages of hard and soft materials and gathers the advantages, and further enables wide application development of hard and soft materials in the material domain. Is expected to play an important role.

FIG. 1 is a diagram showing a conceptual diagram of a composite material according to the present invention. FIG. 2 is a view showing a photograph of the adherend material used in this example. FIG. 3 is a view showing a SEM photograph (part 1) of the surface of the adherend used in this example. FIG. 4 is a view showing an SEM photograph (No. 2) of the surface of the adherend used in this example. FIG. 5 is a view showing an SEM photograph (No. 3) of the surface of the adherend used in this example. FIG. 6 is a diagram showing measurement data of the surface roughness of the glass filters (P-5, P-16, P-40, P-100, P-160, P-250). FIG. 7 is a diagram showing measurement data of the surface roughness of the porous ceramic material. FIG. 8 is a view showing the porosity of the glass filter (P-5, P-16, P-40, P-100, P-160, P-250). FIG. 9 is a diagram showing a conceptual diagram of a method for measuring the fracture energy of the adhesive surface. FIG. 10 is a diagram showing a conceptual diagram of a procedure of “a method for manufacturing a composite material” according to this example. FIG. 11 is a diagram showing the value of the breaking energy between the six types of bonded filters and the IPN gel. FIG. 12 is a diagram showing the measurement results of the adhesive strength in Example 2. FIG. 13 is a diagram showing the value of the breaking energy between the filter (P-5) adhered in Example 3 and the IPN gel. FIG. 14 is a diagram showing the value of the fracture energy between the porous ceramic material or the like bonded in Example 4 and the IPN gel.

Claims (15)

A composite material composed of an interpenetrating network structure gel including a first network structure and a second network structure, and an adherent material having a rough surface formed on at least a part of the surface,
The first network has a first part constructed on the rough surface of the adherend material and a second part mounted on the first part, which is separate from the first part. Have
The second network structure is constructed continuously across the gaps in the first part and the second part of the first network structure, and the interpenetrating network structure gel is directly on the rough surface of the adherend. Bonded composite material.   The composite material according to claim 1, wherein the deposition material is a hard material.   The composite material according to claim 1 or 2, wherein the adherend is a porous material, and the interpenetrating network gel is constructed on the surface of the porous material and in the pores.   The composite material according to claim 2 or 3, wherein the hard material is ceramic or metal.   5. The first network structure is a network structure having a charge, and the second network structure is a network structure that is electrically neutral or has a lower charge than the first network structure. A composite material according to any one of the above. After applying the first monomer solution (1) containing the first monomer component (1) to the rough surface of the adherend, the solution is subjected to polymerization and crosslinking reaction, whereby the first of the first network gel is obtained. A first step of constructing a site on the rough surface of the adherend,
A second step of obtaining a second part of the first network structure by carrying out polymerization and crosslinking reaction on the first monomer solution (2) including the first monomer solution (2);
A third step of introducing a second monomer solution (1) containing a second monomer component (1) into the first part of the first network structure;
A fourth step of introducing a second monomer solution (2) containing a second monomer component (2) into the second part of the first network structure, and the first step containing the second monomer solution (1). Polymerization and cross-linking reaction are performed on the second monomer solution (1) and the second monomer solution (2) in a state where the portion and the second portion containing the second monomer solution (2) are combined. A fifth step of continuously building a second network structure across both gaps in the first part and the second part of the first network structure,
A method for producing a composite material comprising an interpenetrating network structure gel and a deposition material.   The method of claim 6, wherein the deposition material is a hard material.   The method according to claim 6 or 7, wherein the deposition material is a porous material.   The method according to claim 7 or 8, wherein the hard material is ceramic or metal.   The method according to any one of claims 6 to 9, wherein the first monomer component is mainly composed of a charged monomer, and the second monomer component is mainly composed of an electrically neutral monomer. After applying the first monomer solution (1) containing the first monomer component (1) to the rough surface of the adherend, the solution is subjected to polymerization and crosslinking reaction, whereby the first of the first network gel is obtained. A first step of constructing a site on the rough surface of the adherend,
A second step of obtaining a second part of the first network structure by carrying out polymerization and crosslinking reaction on the first monomer solution (2) including the first monomer solution (2);
A third step of introducing a second monomer solution (1) containing a second monomer component (1) into the first part of the first network structure;
A fourth step of introducing a second monomer solution (2) containing a second monomer component (2) into the second part of the first network structure, and the first step containing the second monomer solution (1). Polymerization and cross-linking reaction are performed on the second monomer solution (1) and the second monomer solution (2) in a state where the portion and the second portion containing the second monomer solution (2) are combined. A fifth step of continuously building a second network structure across both gaps in the first part and the second part of the first network structure,
Adhering an interpenetrating network gel to an adherend.   The method of claim 11, wherein the deposition material is a hard material.   The method according to claim 11 or 12, wherein the deposition material is a porous material.   The method according to claim 12 or 13, wherein the hard material is ceramic or metal.   The method according to any one of claims 11 to 14, wherein the first monomer component is mainly composed of a monomer having a charge, and the second monomer component is composed mainly of a monomer having no charge.

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