WO2011040072A1

WO2011040072A1 - Resin composition

Info

Publication number: WO2011040072A1
Application number: PCT/JP2010/055892
Authority: WO
Inventors: 俊香山; 実富田; 有希子清水; 輝充小谷; 圭高橋
Original assignee: ソニー株式会社; 昭和電工株式会社
Priority date: 2009-09-30
Filing date: 2010-03-31
Publication date: 2011-04-07
Also published as: CN102227476A

Abstract

A resin composition characterized by comprising (A) a biodegradable resin, (B) either at least one inorganic filler selected from among fibrous inorganic fillers, plate-shaped inorganic fillers, rod-shaped inorganic fillers, and particulate inorganic fillers, or a water-repellent organic filler, and (C) a compound or resin that has at least two isocyanate groups. Though the resin composition contains a biodegradable resin as the main resin component, the resin composition can provide molded articles having excellent hydrolysis resistance, mechanical characteristics, and dimensional stability.

Description

Resin composition

The present invention relates to a resin composition capable of giving a molded article excellent in hydrolysis resistance, mechanical properties and dimensional stability.

Petroleum-based resins are excellent in mechanical properties, dimensional stability, processability, and other properties, and are therefore used as resin materials for covers and cases for various applications and housings for electrical appliances. However, in recent years, due to increased awareness of environmental problems, proposals have been made to use biodegradable resins that can be decomposed in the natural environment instead of conventional petroleum resins. However, biodegradable resins are generally inferior in mechanical properties such as tensile strength and tensile elastic modulus than petroleum-based resins, and cause a decrease in strength due to hydrolysis degradation, so their uses are extremely limited.

Therefore, as a solution to such a problem, a resin composition in which a plant fiber containing cellulose and lignin and an isocyanate resin are blended at a predetermined ratio with a biodegradable resin such as polylactic acid has been proposed. (For example, see Patent Document 1).

JP 2008-163284 A

However, the molded product obtained from the resin composition described in Patent Document 1 has a relatively good mechanical property, but is a precision component that requires a high degree of dimensional accuracy because of its poor dimensional stability. There was a problem that it could not be used.
Therefore, the present invention has been made to solve the above-described problems, and a molding in which a biodegradable resin is blended as a main resin component and is excellent in hydrolysis resistance, mechanical properties, and dimensional stability. It aims at providing the resin composition which can give a body.

Therefore, as a result of intensive studies to solve the above problems, the present inventors have found that a biodegradable resin, an inorganic filler having a specific shape or an organic filler having water repellency, and a bifunctional or higher functional isocyanate. The present inventors have found that a resin composition containing a group-containing compound or resin solves the above problems, and has completed the present invention.
That is, the present invention provides at least one inorganic filler selected from (A) a biodegradable resin and (B) a fibrous inorganic filler, a plate-like inorganic filler, a rod-like inorganic filler, and a granular inorganic filler. Or it is the resin composition characterized by including the organic filler which has water repellency, and (C) the compound or resin which has an isocyanate group more than bifunctional.

Component (B) is preferably at least one selected from crushed shell, mica, basalt fiber, glass fiber, carbon fiber and calcium carbonate, or an organic filler having water repellency. As the organic filler having water repellency, an organic filler having a cuticle layer such as mammalian hair, insect exoskeleton, mollusk shell, egg, rice husk, etc. is preferable. It is particularly preferable in terms of sex.
Component (B) is blended in an amount of 20% to 80% by mass with respect to the total of component (A) and component (B), and component (C) is added to the sum of component (A) and component (C). It is preferable that 0.1% by mass to 5% by mass is blended.
Component (A) is at least one selected from biodegradable aliphatic polyester, biodegradable aliphatic-aromatic copolymer polyester, polylactic acid, and a copolymer of β-hydroxybutyric acid and β-hydroxyvaleric acid. It is preferable that
It is preferable that the resin composition of the present invention further contains at least one selected from acid-modified polyolefin and ethylene vinyl acetate copolymer.
The resin composition of the present invention may further contain at least one thermoplastic resin selected from polypropylene, polystyrene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, polyethylene, and thermoplastic elastomer.
Further, by using a biodegradable resin having an MFR (190 ° C.) of 5 to 300 g / 10 min as the component (A), a resin composition suitable for injection molding can be obtained. By using a biodegradable resin having an A of 0.1 to 20 g / 10 min, a resin composition suitable for extrusion molding or foam molding can be obtained.

According to the present invention, it is possible to provide a resin composition capable of giving a molded article excellent in hydrolysis resistance, mechanical properties and dimensional stability. The molded body obtained from the resin composition according to the present invention can be applied to precision parts that require high dimensional accuracy.

Hereinafter, the resin composition according to the present invention will be described in detail.

(A) Biodegradable Resin The biodegradable resin used in the present invention includes biodegradable aliphatic polyester, biodegradable aliphatic-aromatic copolymer polyester, polylactic acid, β-hydroxybutyric acid and β-hydroxykichi Examples thereof include copolymers with herbic acid, and these may be used alone or in combination of two or more. More specific examples of biodegradable resins include polybutylene succinate, polycaprolactone, polylactic acid, polybutylene succinate adipate, polyethylene succinate, a copolymer of β-hydroxybutyric acid and β-hydroxyvaleric acid, Examples thereof include a copolymer of terephthalic acid, butanediol, and adipic acid, poly (ethylene terephthalate / succinate), polyvinyl alcohol, poly (caprolactone / butylene succinate), and the like. Among these biodegradable resins, polybutylene succinate is preferable in terms of physical properties and availability. Furthermore, in the case of foam molding, a branched aliphatic polyester is preferred. Commercially available products may be used as the aliphatic polyester, and examples include Bionole (registered trademark) series manufactured by Showa Polymer Co., Ltd. and CBS series manufactured by Daicel Chemical Industries, Ltd.
When the resin composition according to the present invention is injection-molded, the MFR of the biodegradable resin (measured under a load of 190 ° C. and 2.16 kg) is preferably 5 to 300 g / 10 min. In the case of molding, the MFR (190 ° C.) of the biodegradable resin is preferably 0.1 to 20 g / 10 min.
Further, the melting point and number average molecular weight of the biodegradable resin are not particularly limited, but in terms of moldability, the melting point is 90 ° C. to 120 ° C., and the number average molecular weight is 40,000 to 88,000. It is preferable that

(B) Inorganic filler and organic filler The inorganic filler used in the present invention is at least one selected from a fibrous inorganic filler, a plate-like inorganic filler, a rod-like inorganic filler, and a granular inorganic filler. . Fibrous, plate-like, and rod-like shapes are often apparent from the observation of the shape of the inorganic filler, but the difference from the indefinite shape is that the aspect ratio is 3 or more is fibrous, plate-like, or rod-like. It can be said. More specific examples of such inorganic fillers include crushed shells, mica, basalt fibers, glass fibers, carbon fibers, granular calcium carbonate, etc., and these may be used alone. You may combine 2 or more types. In order to improve the adhesion with the component (A), it is preferable that the granular calcium carbonate is surface-treated with a silane coupling agent, a fatty acid, paraffin wax or the like. Examples of the silane coupling agent include silane coupling agents having a vinyl group, an epoxy group, an amino group, a methacryl group, a mercapto group, and the like. Examples of fatty acids include stearic acid, oleic acid, linoleic acid, and the like. Among these inorganic fillers, crushed shells are preferable in that the balance between the resin composition characteristics such as dimensional stability and the cost is good. Shell pulverized products are scallops, oysters, clams, clams, sea cucumbers, and other shells that have been crushed with a hammer mill, roller mill, ball mill, jet mill, etc., with a preferred average particle size of 1 μm to 100 μm. It is. More preferably, it is 5 μm to 50 μm, and most preferably 5 μm to 10 μm.
The organic filler used in the present invention has water repellency. Examples of the organic filler having water repellency include organic fillers having a cuticle layer. Specifically, mammalian hair, insect exoskeletons, mollusk shells, eggs, rice husks, etc. are crushed to a predetermined particle size. These may be used, and these may be used alone or in combination of two or more. Among these organic fillers, crushed rice husks are preferable in terms of availability.
Moreover, you may use together the inorganic filler and organic filler which were mentioned above as needed.
In the resin composition of the present invention, the above-mentioned component (B) is preferably blended in an amount of 20% by mass to 80% by mass with respect to the total of the component (A) and the component (B), and 30% by mass to 60% by mass. % Is more preferable. When the blending amount of the component (B) is within the above range, the balance between rigidity and workability can be further improved.

(C) Compound or resin having a bifunctional or higher functional isocyanate group The compound or resin having a bifunctional or higher functional isocyanate group used in the present invention has two or more isocyanate groups in one molecule. , 4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, polymethylene polyphenyl diisocyanate, tolidine diisocyanate, 1,4-diisocyanatobutane, hexa Methylene diisocyanate, 1,5-diisocyanato-2,2-dimethylpentane, 2,2,4-trimethyl-1,6-diisocyanatohexane, 2,4,4-trimethyl-1,6-diisocyanatohexane, 1,10-diisocyanatodecane, , 3-diisocyanatocyclohexane, 1,4-diisocyanatocyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane, 4,4′-diisocyanatodicyclohexylmethane, 2, 4-hexahydrotoluene diisocyanate, 2,6-hexahydrotoluene diisocyanate, perhydro-2,4'-diphenylmethane diisocyanate, perhydro-4,4'-diphenylmethane diisocyanate, naphthalene 1,5-diisocyanate, xylylene diisocyanate, 1 , 3-bis (isocyanatomethyl) cyclohexane, tetramethylxylylene diisocyanate, etc., or those reacted with a monovalent or polyvalent nonionic polyalkylene ether alcohol, 2,4-tolyl Those obtained by adding a polyhydric alcohol to diisocyanate and 2,6-tolylene diisocyanate hexamethylene diisocyanate, polyisocyanurate, polyisocyanate, polyurethane resins. These may be used alone or in combination of two or more.
Commercially available products and resins having such a bifunctional or higher isocyanate group include Aquanate (registered trademark) 100, 105, 120, 200, 210 manufactured by Nippon Polyurethane Industry Co., Ltd., and Cleran (registered trademark) manufactured by Bayer. ) VPLS2256 and the like.
In the resin composition of the present invention, the component (C) described above is preferably blended in an amount of 0.1% by mass to 5% by mass with respect to the total of the component (A) and the component (C). More preferably, it is blended in an amount of 2 to 2% by mass. When the blending amount of the component (C) is within the above range, the strength and hydrolysis resistance of the molded product can be further improved.

The resin composition of the present invention may contain at least one selected from acid-modified polyolefin and ethylene vinyl acetate copolymer for the purpose of further improving the strength of the molded product. Examples of the acid-modified polyolefin include those obtained by graft polymerization of a polyolefin such as polyethylene and polypropylene and a polymerizable carboxylic acid compound, and those obtained by copolymerizing a resin raw material monomer and a polymerizable carboxylic acid compound. Examples of the polymerizable carboxylic acid compound include maleic anhydride, itaconic anhydride, acrylic acid, methacrylic acid, maleic acid, itaconic acid and the like. These may be used alone or in combination of two or more. Also good. In particular, maleic anhydride is preferred for graft polymerization, and acrylic acid, methacrylic acid and maleic anhydride are preferred for copolymerization. The graft ratio (or copolymerization ratio) of the polymerizable carboxylic acid compound in the acid-modified polyolefin is preferably 1% by mass to 30% by mass. The ethylene vinyl acetate copolymer is a copolymer of ethylene and vinyl acetate. From the viewpoint of the strength of the molded product, the vinyl acetate content is preferably 65% by mass or more, more preferably acetic acid. Those having a vinyl content of 70% by mass or more, most preferably those having a vinyl acetate content of 80% by mass to 99% by mass. Examples of the ethylene vinyl acetate copolymer having such a vinyl acetate content include a powdered one obtained by spray-drying an ethylene vinyl acetate copolymer emulsion using polyvinyl alcohol as a protective colloid. Examples of the products include Loan Fix 3000 manufactured by Showa Polymer Co., Ltd., and KBE-68A and KBE-68B manufactured by Kuraray Co., Ltd.
When at least one selected from an acid-modified polyolefin and an ethylene vinyl acetate copolymer is blended with the resin composition of the present invention, the blending amount is 1% by mass to 20% by mass with respect to the entire resin composition. It is preferable.

Moreover, you may mix | blend surfactant with the resin composition of this invention in order to improve the moldability and the intensity | strength of the molded product obtained. Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants. Among them, nonionic surfactants that are solid at room temperature are preferable.
Examples of such commercially available surfactants include polyoxyethylene alkyl ethers, polyoxyethylene sorbitol fatty acid esters, and glycerin fatty acid esters manufactured by Kao Corporation.
When a surfactant is blended, the blending amount is preferably 0.1% by mass to 5% by mass with respect to the entire resin composition.

In addition to the components described above, known additives can be added to the resin composition of the present invention within a range that does not impair the effects of the present invention. Examples of such additives include surfactants, antioxidants, scratch inhibitors, ultraviolet absorbers, antistatic agents, flame retardants, lubricants, colorants (dyes and pigments), foaming agents, and fragrances. . In addition, the resin composition of the present invention includes known polypropylene (PP), polystyrene, acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate, polyethylene, thermoplastic elastomer, etc., as long as the effects of the present invention are not impaired. These thermoplastic resins may be blended. Examples of the thermoplastic elastomer include styrene thermoplastic elastomer, olefin thermoplastic elastomer, polyester thermoplastic elastomer, polyamide thermoplastic elastomer, urethane thermoplastic elastomer, nitrile thermoplastic elastomer, fluorine thermoplastic elastomer, Examples thereof include polybutadiene-based thermoplastic elastomers and silicone-based thermoplastic elastomers.

The resin composition of the present invention can be obtained by uniformly melting and mixing the above-described components using a mixing apparatus known in the technical field such as an extruder. The mixing temperature is preferably about 10 to 100 ° C. higher than the melting point of the resin. The resin composition of the present invention may be formed by injection molding, blow molding, stretch blow molding, or the like, or may be formed by foamed sheet molding, board molding, or the like, or water-cooled inflation molding or air-cooled inflation molding. A film product may be obtained by extrusion molding using a T-die, extrusion lamination molding, or the like.

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not limited to these.
<Example 1>
Polybutylene succinate as biodegradable resin (Bionor # 1010, Showa Polymer Co., Ltd., melting point 110 ° C., number average molecular weight 68,000, MFR 10 g / 10 min) 50 parts by mass, scallop shell pulverized product as inorganic filler (Those that passed through a 100 mesh sieve) 50 parts by mass and 0.5 parts by mass of Aquanate 105 (manufactured by Nippon Polyurethane Industry Co., Ltd.) as a compound having a bifunctional or higher isocyanate group were melt-kneaded and pellets of the resin composition Got. A test piece having a length of 30 mm, a width of 15 mm and a thickness of 2 mm was molded from the pellet using an injection molding machine.

<Example 2>
A test piece was molded in the same manner as in Example 1 except that a crushed rice husk (passed through a 100 mesh sieve) was used instead of the scallop shell crushed material.

<Example 3>
A test piece was molded in the same manner as in Example 1 except that granular calcium carbonate (surface treated with stearic acid and passed through a 100 mesh sieve) was used instead of the scallop shell pulverized product.

<Example 4>
70 parts by mass of polybutylene succinate (Bionore # 1050, Showa Polymer Co., Ltd., melting point 110 ° C., number average molecular weight 50,000, MFR 50 g / 10 min), scallop shell crushed material (passed through 100 mesh sieve) 30 mass Part, 0.5 parts by mass of Clerant VPLS 2256 (manufactured by Bayer) and 1 part by mass of maleic anhydride-modified polypropylene (Yumex (registered trademark) 1010 by Sanyo Chemical Industries) were melt-kneaded to obtain pellets of the resin composition. . A test piece having a length of 30 mm, a width of 15 mm and a thickness of 2 mm was molded from the pellet using an injection molding machine.

<Example 5>
Polybutylene succinate as biodegradable resin (Bionor # 1010, Showa Polymer Co., Ltd., melting point 110 ° C., number average molecular weight 68,000, MFR 10 g / 10 min) 50 parts by mass, scallop shell pulverized product as inorganic filler (Those that passed through a 100 mesh sieve) 30 parts by mass Aquanate 105 (manufactured by Nippon Polyurethane Industry Co., Ltd.) as a compound having a difunctional or higher functional isocyanate group 0.5 parts by mass and ABS (Toyolac Co., Ltd., registered) (Trademark) 700 314 B1) 20 parts by mass was melt-kneaded to obtain pellets of a resin composition. A test piece having a length of 30 mm, a width of 15 mm and a thickness of 2 mm was molded from the pellet using an injection molding machine.

<Comparative Example 1>
A test piece was molded in the same manner as in Example 1 except that corn starch (manufactured by Nippon Corn Starch Co., Ltd.) was used instead of the scallop shell pulverized product.

<Comparative Example 2>
A test piece was molded in the same manner as in Example 2 except that bamboo powder was used in place of the scallop shell pulverized product.

<Evaluation of mechanical properties>
About the test piece, the tensile test was done according to JISK7162 method, and the tensile strength and the tensile elasticity modulus were measured. The results are shown in Tables 1 and 2.

<Evaluation of hydrolysis resistance>
The test piece was placed in a constant temperature and humidity chamber at 65 ° C. and 90% RH and allowed to stand for 150 hours, and then the test piece was taken out of the constant temperature and humidity chamber and allowed to stand at room temperature for 24 hours. The tensile test of this test piece was implemented, and the retention rate with respect to the initial physical properties (physical properties immediately after molding) was determined for the tensile strength. Evaluation was made according to the following criteria. The results are shown in Tables 1 and 2.
○: Retention rate after 150 hours is 50% or more ×: Retention rate after 150 hours is less than 50%

<Evaluation of dimensional stability>
The test pieces marked at intervals of 10 cm were placed in a constant temperature and humidity chamber at 65 ° C. and 90% RH and allowed to stand for 150 hours, and then the test pieces were taken out from the constant temperature and humidity chamber and allowed to stand at room temperature for 24 hours. The interval between the marks on the test piece was measured to obtain the elongation percentage. The results are shown in Tables 1 and 2. In addition, elongation rate is the value which carried out arithmetic average of the measured value of 3 times.

As is apparent from the results of Tables 1 and 2, Examples 1 to 5 not only have excellent mechanical properties and hydrolysis resistance, but also have an elongation of 23%, 41%, 37%, 26% and 25%. It is extremely excellent in dimensional stability. On the other hand, Comparative Examples 1 and 2 (corresponding to the composite material of Patent Document 1) cannot be used for precision parts that require high dimensional accuracy because the elongation exceeds 50%.

Claims

(A) biodegradable resin, (B) at least one inorganic filler selected from fibrous inorganic filler, plate-like inorganic filler, rod-like inorganic filler, and granular inorganic filler, or water-repellent organic A resin composition comprising a filler and (C) a compound or resin having a bifunctional or higher functional isocyanate group.
The resin composition according to claim 1, wherein the component (B) is at least one selected from crushed shell, mica, basalt fiber, glass fiber, carbon fiber, and calcium carbonate.
The resin composition according to claim 1, wherein the component (B) is an organic filler covered with a cuticle layer.
4. The resin composition according to claim 3, wherein the organic filler covered with the cuticle layer is a crushed rice husk.
The component (B) is blended in an amount of 20 to 80% by mass with respect to the sum of the components (A) and (B), and the component (C) is added to the sum of the components (A) and (C). The resin composition according to any one of claims 1 to 4, which is blended in an amount of 0.1 to 5% by mass.
The component (A) is at least one selected from biodegradable aliphatic polyester, biodegradable aliphatic-aromatic copolymer polyester, polylactic acid, and a copolymer of β-hydroxybutyric acid and β-hydroxyvaleric acid. 6. The resin composition according to claim 1, wherein the resin composition is any one of the following.
The resin composition according to any one of claims 1 to 6, further comprising at least one selected from an acid-modified polyolefin and an ethylene vinyl acetate copolymer.
8. The method according to claim 1, further comprising at least one thermoplastic resin selected from polypropylene, polystyrene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, polyethylene, and a thermoplastic elastomer. The resin composition as described.
9. A resin composition for injection molding, wherein the MFR (190 ° C.) of the component (A) contained in the resin composition according to any one of claims 1 to 8 is 5 to 300 g / 10 minutes.
Extrusion molding or foam molding characterized in that the MFR (190 ° C) of the component (A) contained in the resin composition according to any one of claims 1 to 8 is 0.1 to 20 g / 10 min. Resin composition.