JPH0873634A - Low elastic polymer net-like structure - Google Patents

Abstract

PURPOSE: To obtain the low elastic polymer net-like structure capable of being used as a material suitably employed as a vibration-preventing material, a damping material, an impact-absorbing material, etc., and free from bleeding. CONSTITUTION: The low elastic polymer net-like structure is obtained by mixing <=35vol.% of a polymer material having a number-average mol.wt. of >=20000 with >=65vol.% of a low mol.wt. material having a number-average mol.wt. of <=20000. The low elastic polymer net-like structure has a structure main body in which the polymer material forms a three-dimensional continuous net- like skeleton structure, in which the low molecule material is filled in the inner communicated spaces of the skeleton, and which has partially or wholly a 1-1000μm-thick coating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-elasticity polymer network structure suitably used as a vibration damping material, a vibration damping material, a cushioning material, a shock absorbing material and the like.

[0002]

2. Description of the Related Art Generally, performances required for applications such as vibration-proof materials, vibration-damping materials, shock-absorbing materials, shock-absorbing materials include tensile strength, tensile stress, elongation, hardness, weather resistance, etc. , Its material is
A versatile rubber material is used. However, since the performance of these versatile rubber materials depends on the performance of the raw rubber itself, it has been considered difficult to combine the above performances.

Further, recently, in the field of polymer materials, a rubber material having high performance, high function, economical efficiency and versatility and having a very low elasticity has been demanded. Therefore, the Applicant obtained by mixing a small amount of a high molecular weight material with a large amount of a low molecular weight material, the high molecular weight material forms a three-dimensional continuous network skeleton structure, and the low molecular weight material of this skeleton is A low-elasticity polymer network structure that fills the internal communication space is disclosed (Japanese Patent Laid-Open No. 5-239265). However, in applications such as direct contact with the body, for example, shoes, sports materials, cushions, biological protection materials, etc., exudation of low molecular weight components retained in large amounts in this structure (hereinafter abbreviated as bleeding property) ) Was a problem.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and can be used as a material suitably used as a vibration damping material, a vibration damping material, a shock absorbing material, a shock absorbing material, or the like. Provided is a novel low-elasticity polymer network structure having low elasticity and no bleeding.

[0005]

The low-elasticity polymer network structure according to claim 1 of the present invention has a number average molecular weight of 20,
It is obtained by mixing 35 volume% or less of a polymer material of 000 or more and 65 volume% or more of a low molecular weight material having a number average molecular weight of 20,000 or less, and the polymer material forms a three-dimensional continuous network skeleton structure. A structure body having the structure body formed by filling the internal communication space of the skeleton with the low-molecular material, and a part or the whole of the structure body having a thickness of 1 μm to 1,000 μm. It is characterized in that a layer is provided.

Further, the low elastic polymer network structure according to claim 2 of the present invention is characterized in that the coating layer is a barrier resin.

Further, the low-elasticity polymer network structure according to claim 3 of the present invention is characterized in that the solubility parameter difference between the polymer material and the low-molecular material is 3.0 or more.

Further, in the low elastic polymer network structure according to claim 4 of the present invention, the Asker C hardness of the structure body is 4
It is characterized in that it is 5 ° or less.

That is, the inventors of the present invention have conducted extensive studies on a low-elasticity polymer network structure having excellent properties, and as a result, the low-elasticity polymer network structure of the present invention is By providing a coating layer on a part or the whole,
The inventors have found that the bleeding property, which has been a drawback of conventional low-elasticity materials, can be significantly improved, and completed the present invention.

The present invention will be described in detail below. The polymer material in the present invention has a number average molecular weight of 20,0.
00 or more, especially 30,000 or more, especially 40,0
00 or more thermoplastic polymer materials are preferable, for example, various thermoplastic elastomers such as styrene type (butadiene styrene type, isoprene styrene type), ester type, amide type, urethane type, and their hydrogenation, etc. Modified products, styrene-based, ABS-based, olefin-based (ethylene-based, propylene-based, ethylene-propylene-based,
Ethylene styrene type, propylene styrene type, etc.), vinyl chloride type, acrylic acid ester type (methyl acrylate type, etc.), methacrylic acid ester type (methyl methacrylate type, etc.) carbonate type, acetal type, nylon type, halogenated poly Ether type (chlorinated polyether type, etc.), halogenated olefin type (tetrafluoroethylene type,
Fluorinated-ethylene chloride type, fluorinated ethylene propylene type, etc.), cellulose type (acetyl cellulose type, ethyl cellulose type, etc.), vinylidene type, vinyl butyral type, alkylene oxide type (propylene oxide type, etc.) thermoplastic resin, and Examples include rubber-modified products of these resins.

As a specific thermoplastic polymer material, it is particularly preferable to use a material having a portion which easily forms a hard block such as a crystal structure or an agglomerate structure and a soft block such as an amorphous structure, among them. Specifically, the following are mentioned.

A block copolymer of polyethylene / butylene and an ethylene-styrene random copolymer obtained by hydrogenating a block copolymer of polybutadiene and a butadiene-styrene random copolymer. A block copolymer of polybutadiene and polystyrene, or a block copolymer of polyethylene / butylene and polystyrene obtained by hydrogenating a block copolymer of polybutadiene or an ethylene-butadiene random copolymer and polystyrene. Ethylene-propylene rubber. Of these, a block copolymer of polyethylene and an ethylene-styrene random copolymer is particularly preferable, and a crystalline one is more preferable.

These various thermoplastic polymer materials are mainly used alone, but two or more kinds may be blended and used.

On the other hand, as a low molecular weight material, the viscosity at 100 ° C. is not more than 5 × 10 ⁵ centipoise, especially 1 × 1.
Is preferably 0 ⁵ centipoise or less, from the viewpoint of molecular weight, number average molecular weight of the low molecular material 20,
000 or less, especially 10,000 or less, especially 5,000
It is preferably 0 or less. As such a low molecular weight material, a liquid or liquid material at room temperature is usually preferably used. Further, both hydrophilic and hydrophobic low molecular weight materials can be used. The low molecular weight material is not particularly limited, but the following materials are suitable.

Softening material: Softening material for various types of rubber or resin such as mineral oil, vegetable oil and synthetic. Examples of mineral oil-based oils include process oils such as aromatic oils, naphthene oils, and paraffin oils. Examples of vegetable oils include castor oil, cottonseed oil, linseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, peanut oil, wood wax, pine oil, olive oil and the like.

Plasticizers: Various ester-based plasticizers such as phthalic acid esters, mixed phthalic acid esters, aliphatic dibasic acid esters, glycol esters, fatty acid esters, phosphoric acid esters, stearic acid esters, epoxy-based plasticizers, etc. Plasticizers for plastics or phthalates, adipates, sebacates, phosphates,
NBR plasticizers such as polyether and polyester.

Tackifier: Various tackifiers (tackifier) such as coumarone resin, coumarone-indene resin, phenol terpene resin, petroleum hydrocarbon, rosin derivative and the like.

Oligomer: Crown ether, fluorine-containing oligomer, polyisobutylene, xylene resin, chlorinated rubber, polyethylene wax, petroleum resin, rosin ester rubber, polyalkylene glycol diacrylate,
Liquid rubber (polybutadiene, styrene-butadiene rubber, butadiene-acrylonitrile rubber, polychloropolene, etc.), silicone-based oligomers, various oligomers such as poly-α-olefins.

Lubricants: Hydrocarbon lubricants such as paraffin and wax, fatty acid lubricants such as higher fatty acids and oxyfatty acids, fatty acid amide lubricants such as fatty acid amides and alkylenebisfatty acid amides, fatty acid lower alcohol esters, fatty acid polyhydric alcohol esters. , Ester lubricants such as fatty acid polyglycol ester, fatty alcohol,
Various lubricants such as alcohol-based lubricants such as polyhydric alcohols, polyglycols and polyglycerols, metal soaps, mixed lubricants.

In addition, latex, emulsion, liquid crystal, bituminous composition, clay, natural starch, sugar, inorganic silicon oil, phosphazene and the like are also suitable as the low molecular weight material. In addition, animal oil such as cow oil, pig oil, horse oil,
Bird oil or fish oil: honey, fruit juice, or dairy products such as chocolate, yogurt, hydrocarbon-based, halogenated hydrocarbon-based, alcohol-based, phenol-based, ether-based, acetal-based, ketone-based, fatty acid-based, ester-based,
Organic solvents such as nitrogen compounds and sulfur compounds: Or various medicinal ingredients, soil modifiers, fertilizers, petroleum,
Water, aqueous solution, etc. are also used.

These low molecular weight materials may be used alone or in combination of two or more.

The low-elasticity polymer network structure of the present invention comprises a low-molecular material used in order to obtain a low-elasticity polymer network structure containing a large amount of low-molecular materials by using a large amount of low-molecular materials and polymer materials. Solubility parameter of each polymer material δ =
It is preferable to select both materials so that the difference of (ΔE / V) ^1/2 (ΔE = molar evaporation energy, V = mol volume) is 3.0 or less, preferably 2.5 or less. If this difference exceeds 3.0, from the viewpoint of compatibility of both materials, it is difficult to retain a large amount of low molecular weight materials, which is an obstacle to low elasticity of the obtained low elastic polymer network structure. Bleed is likely to occur, which is not preferable.

The low-elasticity polymer network structure of the present invention may further contain the following fillers, if necessary. That is, clay, diatomaceous earth, carbon black, silica, talc, barium sulfate, calcium carbonate,
Scale-like inorganic fillers such as magnesium carbonate, metal oxides, mica, graphite and aluminum hydroxide, various metal powders, wood chips, glass powders, ceramics powders, granular or powdery solid fillers such as granular or powder polymers, etc. Various natural or artificial short fibers, long fibers (for example, straws, hairs, glass fibers, metal fibers, and other various polymer fibers) can be blended.

Further, it is possible to reduce the weight by blending a hollow filler, for example, an inorganic hollow filler such as a glass balloon or a silica balloon, or an organic hollow filler made of polyvinylidene fluoride or a polyvinylidene fluoride copolymer. It is also possible to mix various foaming agents in order to improve various physical properties such as weight reduction.
It is also possible to mechanically mix the gas at the time of mixing. In addition, titanium white (TiO ₂ , white), red iron oxide (F
e ₂ O _3, brown), chrome yellow (PbCrO _4, yellow), calcium dye is said to inorganic pigments and lake pigments ultramarine blue, magnesium or heavy metal salts, various pigments such as organic pigments such as phthalocyanine blue need to Can be blended accordingly.

The coating layer of the present invention is provided to protect the main body of the low elastic polymer network structure from factors such as water, moisture, air, oxygen, carbon dioxide, nitrogen, ultraviolet rays, light, microorganisms and heat. Of these, the barrier resins described below are preferred. The barrier resin referred to herein is, for example, ethylene / vinyl alcohol copolymer resin, vinylidene chloride resin, polyacrylonitrile, polyvinyl alcohol, nylon resin, polyester, aluminum foil,
Aluminum foil / moisture-proof cellophane, aluminum foil / wax glassine paper, aluminum foil / cellulose acetate, ordinary cellophane, paper, vinyl chloride, polyethylene, polypropylene, polystyrene, polyurethane, polycarbonate, etc. Can be used. The thickness of the coating layer is 1 μm-1,
000 μm is preferable, and if the thickness is less than 1 μm, the strength of the coating layer cannot be maintained, and if the thickness exceeds 1,000 μm, low elasticity is lost, which is not preferable.

The three-dimensional continuous reticulated skeleton structure formed of the polymer material forming the low-elasticity polymer reticulated structure of the present invention has an average skeleton diameter of 50 μm or less, preferably 30.
μm or less, the average diameter of the cells (mesh) is 500 μm or less,
It is preferably 300 μm or less, and when the volume fraction of the polymer material is defined as [volume of polymer material / (volume of polymer material + volume of low molecular weight material)] × 100 (%), It is desirable that the volume fraction is 35% or less, particularly 30% or less.

The low-elasticity polymer network structure of the present invention forms a network-like skeleton structure in which the polymer material is three-dimensionally continuous with a predetermined amount of the polymer material and the low-molecular material and, if necessary, other compounding agents. It can be obtained by mixing under the mixing conditions to be obtained, but in this case, it has a uniform three-dimensional continuous network skeleton structure of a high molecular material, low bleeding of a low molecular weight material, and a low molecular weight satisfying the above-mentioned characteristics. In order to obtain the elastic polymer network structure, it is preferable to use a high-shear type mixer as the mixer, in particular, a high shear force and a high shear rate can be given between the fixed wall and the rotating rotor. In addition, the distance (clearance) between the fixed wall and the rotating portion (rotor) is t (m), and the rotating peripheral speed of the rotor is v (m /
sec) and the shear rate V of the rotor is V = v / t (s
ec ⁻¹ ), V ≧ 5.0 × 10 ² (sec ⁻¹ ) and preferably V ≧ 1.0 × 10 ³ (se
c ⁻¹ ) more preferably V ≧ 2.5 × 10 ³ (se
c ⁻¹ ) Most preferably V ≧ 5.0 × 10 ³ (se
It is advantageous to use a high-shear type special mixer satisfying c ⁻¹ ).

The coating method of the low-elasticity polymer network structure of the present invention is not particularly limited, and the coating method used for industrial and domestic use can be used. Typical examples are as follows. There is a way. Vacuum Packing Method There are two methods, one is to make a vacuum with a nozzle and the other is to put a material to be coated in a container and make the container vacuum. Skin pack method Compared to the above, since the film thickness is thinner, the degree of vacuum is inferior, but
It is suitable for coating materials having complicated shapes.

The degree of vacuum at this time can be arbitrarily set depending on the material and shape of the material to be coated, but generally, atmospheric pressure to about 3 torr is preferable.

Further, the method of sealing the material to be coated after the vacuum is applied by the above method is not particularly limited, and a sealing method used for industrial or domestic use can be used. There are sonic fusion, heat fusion, pressure bonding, and adhesion with an adhesive or the like.

The low-elasticity polymer network structure of the present invention is not particularly limited to a usual bulk shape, gel shape, foam shape, etc., but is in a gel state, particularly a three-dimensional continuous uniform material made of a thermoplastic polymer material. A gel state having a reticulated skeleton structure is particularly effective for the present invention, and a low elastic polymer reticulated structure excellent in filling property and recyclability is provided.

The use of the low elastic polymer network structure of the present invention will be described in detail below. Since the low-elasticity polymer network structure of the present invention can hold a large amount of low-molecular material, the elastic modulus can be controlled to an extremely low range. The present invention can provide products in a wide range of industrial fields. Examples of the vibration-damping / damping / cushioning material include fixing members such as sealing materials, packing, gaskets, grommets, support members such as mounts, hoders and insulators, and cushioning members such as stoppers, cushions and bumpers. Further, it is preferably used as a product such as a cooler, a washing machine, a refrigerator, a fan, a vacuum cleaner, a dryer, a printer, an air blower, or any other device that generates vibration or sound or a home electric appliance. Furthermore, as shock absorbers, sports equipment such as gloves, mitts, golf clubs, and tennis rackets, for insoles of shoes, various toys, audio equipment, electronic / electrical equipment, beds, chairs, and especially for medical applications that keep the same posture for a long time. It is preferably used as a bed, a barber / beauty bed, a theater chair, and a seat material for a vehicle that is subject to vibration.

It can also be used in medical equipment such as artificial legs, artificial hands, robots, electrode materials for measuring electrocardiogram, and electrode materials for low frequency treatment. Further, it is also used as an ultra-low hardness rubber for OA equipment, seismic isolation rubber, anti-vibration rubber, and even racing tires. Further, it is suitable as a low hardness plastic as various forming materials. In addition, since low molecular weight materials such as various liquids can be handled as a solid state, it is suitable for use as a functional material such as an electrolyte solution film, a liquid crystal film, an adhesive film, and a paint film.

[0034]

EXAMPLES The present invention will be described in more detail with reference to the following examples.

(Examples) The materials shown in Table 1 were blended as shown in Table 1 using a high-shear type special mixer ("TK Auto Homo Kixer" manufactured by Tokushu Kika Kogyo Co., Ltd.). After mixing under the mixing conditions shown, the mixture was poured into a mold and molded into a sheet having a thickness of 7 mm to obtain a low elastic polymer network structure.

[Table 1]

[Table 2]

Next, this sheet was punched with a 40 mφ punching blade, and then nylon 1 was applied to this material.
Two films were used to apply a coating layer of about 30 μm by the vacuum packing method and this material was sealed by the high frequency fusion method.

The obtained low elastic polymer network structure was attached to the heel of sports shoes with a double-sided tape or the like. When the main body of the low elastic polymer network structure was not covered, the socks and the like contained some low molecular components. Although it was attached, it was confirmed that the material after coating did not bleed at all, and the impact absorption and fit properties were the same as those before coating.

The hardness of the low elastic polymer network structure body was 36 ° in Asker C and the elongation at break was 900%. In addition, when a section of the structure before coating was cut out and confirmed by an optical microscope, a three-dimensional continuous reticulated skeleton structure (average skeleton diameter 5 μm, made of a thermoplastic polymer organic material,
It was confirmed that an average cell diameter of 20 μm) was formed.

INDUSTRIAL APPLICABILITY As described above, the present invention can be used as a material suitably used as a vibration damping material, a vibration damping material, a shock absorbing material, a shock absorbing material, etc., and has a low elasticity and a high elasticity. A molecular network structure is provided.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mihide Fukahori 2-9-7 Sanada-cho, Hachioji-shi, Tokyo

Claims (4)

[Claims] 1. A polymer obtained by mixing 35% by volume or less of a high molecular weight material having a number average molecular weight of 20,000 or more and 65% by volume or more of a low molecular weight material having a number average molecular weight of 20,000 or less. A low-elasticity polymer reticulated structure having a structure body in which a material forms a three-dimensional continuous reticulated skeleton structure and the low-molecular material fills the internal communication space of the skeleton. A low-elasticity polymer network structure, characterized in that a coating layer having a thickness of 1 μm to 1,000 μm is provided on a part or the whole of the part. 2. The low-elasticity polymer network structure according to claim 1, wherein the coating layer is a barrier resin. 3. The low elastic polymer network structure according to claim 1, wherein the difference in solubility parameter between the high molecular weight material and the low molecular weight material is 3.0 or more. 4. The low-elasticity polymer network structure according to claim 1, wherein the Asker C hardness of the low-elasticity polymer network structure body is 45 ° or less. .