JP5279415B2 - Resin composition and molded body using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an environment consideration type thermoplastic resin composition having high rigidity and small warpage property and excellent in heat-resistance, impact-resistance and moldability. <P>SOLUTION: The resin composition contains 30-95 mass% of a thermoplastic resin (A), and 5-70 mass% of a glass fiber (B) in which a long diameter/a short diameter ratio of the fiber cross section is 1.5-10. A part or a whole part of the thermoplastic resin (A) is a polyamide resin 11 (A1a) or/and polyamide 1010 resin (A1b). 10 pts.mass or more of polyamide 11 resin (A1a) or/and polyamide 1010 resin (A1b) is contained relative to total 100 pts.mass of the thermoplastic resin (A) and the glass fiber (B). <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a resin composition and a molded body using the same, and more particularly to an environmentally friendly thermoplastic resin composition and a molded body using the same.

  Conventionally, polycarbonate (PC) resin and acrylonitrile-butadiene-styrene copolymer (ABS) resin, which are thermoplastic resins, have been used as molding materials for electronic devices such as notebook computers, mobile phones, and office automation equipment. ing. Since these resins easily undergo plastic deformation and absorb impact energy when an impact load is applied, destruction of the electronic device casing is unlikely to occur.

  In recent years, there has been an increasing demand for thinning, downsizing, and weight reduction of electronic device products as described above. For this reason, the molding material of the product casing has not only high impact strength, but also low specific gravity to reduce the weight of the product, high rigidity to reduce the deflection amount under load, and low warpage of the molded product. It is indispensable. Conventionally, the molding materials used for the casing do not satisfy the required performance, such as generally having a high impact resistance and poor thin-wall moldability.

  Therefore, as a molding material for a thin-walled portable device casing that has overcome the above-mentioned problems, a resin composition containing a polyamide resin and a modified polyphenylene ether resin, a liquid crystal polymer, a compatibilizer, and an inorganic filler There is disclosed a resin composition blended with (Patent Document 1). However, impact resistance and low warpage are insufficient. In addition, attempts have been made to improve rigidity, toughness, and dimensional stability by mixing a fibrous reinforcing material with a base material obtained by mixing aromatic polyamide, amorphous polyamide, and polyamide 6 (patent) Reference 2). However, it has not yet provided the rigidity and toughness that can withstand actual use, and the low warpage of the molded product has not been studied.

  On the other hand, in recent years, from the viewpoint of environmental conservation, plant-derived thermoplastic resins such as polylactic acid resin, polyamide 11 resin, and polyamide 1010 resin have attracted attention.

  That is, polylactic acid resin can be produced using plants such as corn and sweet potato as raw materials, and can contribute to saving of depleted resources such as oil. Polylactic acid resin is a crystalline polymer, and has a higher melting point and higher heat resistance than other biodegradable resins. Polylactic acid resins can be mass-produced, so the cost is low and the utility is high.

  However, the polylactic acid resin has not only a long molding cycle due to a slow crystallization speed, but also has a drawback that the resulting molded article is inferior in mechanical strength, impact resistance, flexibility and durability. Therefore, in order to solve such problems, for example, polylactic acid resin is blended with other petroleum-based biodegradable resins and hydrolysis inhibitors having higher performance, and the heat resistance and resistance of the molded product are improved. Studies have been made to improve impact properties and durability (Patent Documents 3 and 4). However, such a resin composition also has a long molding cycle and is insufficient in all aspects of durability, impact resistance, flexibility, and heat resistance.

On the other hand, the polyamide 11 resin and the polyamide 1010 resin are excellent in flexibility and durability as compared with the polylactic acid resin, and are used for applications such as hoses and tubes in various industrial fields. Polyamide 11 resin and polyamide 1010 resin are also produced from plant-derived materials, and are preferable from the viewpoint of environmental considerations. However, because of its high price, it is difficult to spread in a wide range of applications, and it is used only in a limited range as required even in the automobile industry. As general moldings related to automobiles, general-purpose resins such as polypropylene resins are widely used because of their low cost. Further, although the polyamide 11 resin and the polyamide 1010 resin are derived from plants, the amount of carbon dioxide generated in the production process is not low, and is equal to or higher than that of a general-purpose resin such as polyolefin. This is also a problem for widespread use.
JP-A-6-240132 JP 2004-168849 A JP 2002-309074 A JP 2006-321988 A

  An object of the present invention is to provide an environmentally friendly thermoplastic resin composition that solves the above problems and has high rigidity, low warpage, and excellent heat resistance, impact resistance, and moldability. is there.

  As a result of intensive studies to solve the above problems, the present inventors have solved the above problems by a resin composition containing polyamide 11 resin and / or polyamide 1010 resin and glass fibers having a flat cross section. The present invention was reached.

That is, the gist of the present invention is as follows.
(1) Thermoplastic resin (A) 35 to 75 % by mass and glass fiber (B) 25 to 65 % by mass with a major axis / minor axis of the fiber cross section of 1.5 to 10, and a thermoplastic resin ( Part or all of A) is polyamide 11 resin (A1a) or / and polyamide 1010 resin (A1b) and polylactic acid resin (A2) , and the total of 100 masses of thermoplastic resin (A) and glass fiber (B). Containing 10 parts by mass or more of polyamide 11 resin (A1a) and / or polyamide 1010 resin (A1b) with respect to parts ,
A resin composition comprising 5 to 40 parts by mass of a polylactic acid resin (A2) with respect to 100 parts by mass in total of the thermoplastic resin (A) and the glass fiber (B) .

(2) polylactic acid resin (A2) is a peroxide and / or (meth) resin composition, characterized in that it is cross-linked by the acrylic acid ester compound (1).

(3) The layered silicate (C) is contained in an amount of 0.1 to 45 parts by mass with respect to a total of 100 parts by mass of the thermoplastic resin (A) and the glass fiber (B) (1) or The resin composition of (2) .

(4) the total of 100 parts by mass of the thermoplastic resin (A) and glass fiber (B), from plant-derived filler (D), characterized in that it contains 5 to 200 parts by weight (1) ( Any resin composition up to 3) .

(5) The resin composition according to (4) , wherein the plant-derived filler (D) is at least one selected from jute fiber, kenaf fiber, bamboo fiber, hemp fiber, and bagasse fiber.

(6) A molded article obtained by molding any one of the resin compositions (1) to (5) .

  ADVANTAGE OF THE INVENTION According to this invention, it is a thermoplastic resin composition with a high plant origin ratio, can provide the thermoplastic resin composition which is excellent in a moldability, heat resistance, and impact resistance, and has high rigidity. By using this resin composition for parts of electrical products, the range of use of polyamide 11 resin and / or polyamide 1010 resin, which is a low environmental load material, can be greatly expanded, and the industrial utility value is extremely high.

Hereinafter, the present invention will be described in detail.
The resin composition of the present invention is a resin composition containing 30 to 95 mass% of the thermoplastic resin (A) and 5 to 70 mass% of the glass fiber (B), and is a part of the thermoplastic resin (A). Alternatively, it is necessary that all are polyamide 11 resin (A1a) and / or polyamide 1010 resin (A1b).

  In the present invention, examples of the polyamide 11 resin (A1a) include those obtained by polycondensing 11-aminoundecanoic acid using ricinoleic acid in natural castor oil as a raw material. The production method is not particularly limited, and the polyamide 11 resin (A1a) can be produced according to a known method. In the production, additives such as various catalysts and heat stabilizers may be used. As a commercial item of the polyamide 11 resin (A1a), for example, “Rilsan BMN O” manufactured by Arkema Co., Ltd. may be mentioned.

  Examples of the polyamide 1010 resin (A1b) in the present invention include those obtained by polycondensation of sebacic acid and decanediamine using natural castor oil as a raw material. The production method is not particularly limited, and this resin can be produced according to a known method. In the production, additives such as various catalysts and heat stabilizers may be used. The polyamide 1010 resin (A1b) preferably has a biomass carbon content of 50% or more measured in accordance with ASTM (D6866) in consideration of environmental load.

  The polyamide 11 resin (A1a) and the polyamide 1010 resin (A1b) can be used individually, and can be used in some cases.

  In the resin composition of the present invention, the content of the polyamide 11 resin (A1a) and / or the polyamide 1010 resin (A1b) is 100 parts by mass in total of the thermoplastic resin (A) and the glass fiber (B). It must be 10 parts by mass or more. If the content is less than 10 parts by mass, the excellent mechanical properties may not be fully utilized, and the plant-derived ratio is also insufficient.

  The resin composition of the present invention needs to contain glass fiber (B). The glass fiber (B) needs to have a flat cross section having a major axis / minor axis of 1.5 to 10 in the fiber cross section, and the major axis / minor axis is preferably 2.0 to 6.0. . When the major axis / minor axis is less than 1.5, the effect of making the cross section flat is small, and when the major axis / minor axis exceeds 10, the glass fiber itself is difficult to produce.

  In the glass fiber (B), the major axis of the fiber cross section is preferably 10 to 50 μm, more preferably 15 to 40 μm, and still more preferably 20 to 35 μm.

  The ratio (aspect ratio) between the average fiber length and the average fiber diameter of the glass fiber (B) is preferably 2 to 120, more preferably 2.5 to 70, and 3 to 50. Even more preferable. When the aspect ratio is less than 2, the effect of improving the mechanical strength is small. On the other hand, when it exceeds 120, the anisotropy is increased and the appearance of the molded product is deteriorated. In addition, the average fiber diameter of glass fiber means the number average fiber diameter when converting a flat cross-sectional shape into a perfect circle of the same area.

  In the present invention, as the glass fiber (B), a fiber having a general glass composition such as E glass is used, but any composition can be used as long as it can be made into a glass fiber, and is particularly limited. It is not a thing.

  The glass fiber (B) is produced by a known glass fiber production method. Further, the glass fiber (B) contains at least one coupling agent such as a silane coupling agent, a titanium coupling agent, and a zirconia coupling agent in order to improve adhesion to the matrix resin and uniform dispersibility. be able to. Moreover, an antistatic agent, a film formation agent, etc. can also be included. The glass fiber (B) is used in the form of chopped strands which are bundled by a known sizing agent suitable for the resin to be blended, and the bundled glass fiber strands are collected and cut to a certain length.

  In the resin composition of the present invention, the content of the glass fiber (B) is required to be 5 to 70% by mass, preferably 25 to 65% by mass, and 30 to 60% by mass. More preferred. When the content of the glass fiber (B) is less than 5% by mass, warpage increases. Moreover, when this content exceeds 70 mass%, the external appearance of a molded object will deteriorate and manufacture of a resin composition will become difficult.

  In the resin composition of the present invention, the thermoplastic resin (A) may be entirely polyamide 11 resin (A1a) or / and polyamide 1010 resin (A1b), but a part thereof may be polylactic acid resin (A2). ) May be contained. By containing the polylactic acid resin (A2), sink marks during molding can be reduced and dimensional accuracy can be improved. Moreover, what uses various plants, such as corn, as a raw material can be used for polylactic acid resin (A2), and in that case, in addition to dimensional accuracy improvement, a plant origin can be kept high.

  As the polylactic acid resin (A2), poly (L-lactic acid), poly (D-lactic acid), and a mixture or copolymer thereof can be used in terms of heat resistance and moldability.

  It is preferable that content of the polylactic acid resin (A2) in a resin composition is 5-40 mass parts with respect to a total of 100 mass parts of a thermoplastic resin (A) and glass fiber (B). If the content of the polylactic acid resin (A2) is less than 5 parts by mass, sink marks during molding cannot be reduced and dimensional accuracy cannot be improved. When the content exceeds 40 parts by mass, the impact resistance tends to decrease.

  Furthermore, as the polylactic acid resin (A2), it is preferable to use a polylactic acid resin having a crosslinked structure by being crosslinked by a peroxide and / or a (meth) acrylic acid ester compound. Thereby, the crystallinity at the time of shaping | molding can be improved and the heat resistance of a molded object can be improved.

  In the resin composition of the present invention, the thermoplastic resin (A) may be entirely polyamide 11 resin (A1a) and / or polyamide 1010 resin (A1b) as described above, but modified as part thereof. A polyolefin resin (A3) may be contained. By containing the modified polyolefin resin (A3), the impact resistance of the molded product can be improved.

  As the modified polyolefin resin (A3), various modified polyolefin resins including those commercially available can be used. Specific examples of the modified polyolefin resin (A3) include a copolymer of modified ethylene and / or propylene and an α-olefin, an olefin mainly composed of an ethylene component and / or a propylene component, and α, β-unsaturated. Copolymers with carboxylic acids or their derivatives, and graft polymers obtained by grafting α, β-unsaturated carboxylic acids or their derivatives onto polymers of olefins whose main constituent is an ethylene component and / or propylene component, etc. Can be mentioned. Here, as the α, β-unsaturated carboxylic acid, for example, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, nadic acid (endocis-bicyclo [2,2] hept- 5-ene-2,3-dicarboxylic acid) and the like. The derivatives include acid halides, esters, amides, imides, anhydrides, and the like, for example, maleyl chloride, maleimide, acrylic acid amide, methacrylic acid amide, glycidyl methacrylate, maleic anhydride, citraconic anhydride, monomethyl maleate Dimethyl maleate, glycidyl maleate and the like. These may be used singly or in combination of two or more. Among these, maleic anhydride is preferable because it has high reactivity and can provide a molded article having good strength and appearance.

  Among them, a copolymer of modified ethylene and / or propylene and α-olefin is preferable from the viewpoint of the impact resistance effect. Examples of the commercially available products include “Tuffmer” (a series of products such as modified ethylene / α-olefin copolymer) manufactured by Mitsui Chemicals.

  The content of the modified polyolefin resin (A3) in the resin composition is preferably 5 to 85 parts by mass with respect to 100 parts by mass in total of the thermoplastic resin (A) and the glass fiber (B). When the content is less than 5 parts by mass, sufficient effects may not be obtained, and when the content exceeds 85 parts by mass, the heat resistance may be inferior.

  In the present invention, as the thermoplastic resin (A), as the thermoplastic resin other than the polyamide 11 resin (A1a) and / or the polyamide 1010 resin (A1b), the polylactic acid resin (A2) and the modified polyolefin resin (A3) Other thermoplastic resins can also be used. In that case, it is preferable to use an aliphatic biodegradable polyester resin from the viewpoint of environmental conservation.

  Such an aliphatic biodegradable polyester resin is not particularly limited, and may be an oxyacid polymer, a polyester mainly composed of glycol and fatty acid dicarboxylic acid, or a mixture or copolymer thereof. Also good. Examples of the oxyacid component include glycolic acid and ε-caprolactone. Examples of glycols include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, decamethylene glycol, and neopentyl glycol. Aliphatic dicarboxylic acids include succinic acid, adipic acid, suberic acid, and sebacine. Examples include acids, dodecanedioic acid and anhydrides thereof. Furthermore, although the said oxyacid, glycol, and fatty acid dicarboxylic acid can be used in arbitrary combinations, a polyethylene succinate, a polybutylene succinate, a polybutylene adipate etc. are preferable, and a polybutylene succinate is more preferable.

  The resin composition of the present invention may contain a layered silicate (C). By containing the layered silicate (C), the generation of burrs during molding can be reduced.

  As the layered silicate (C), various materials such as montmorillonite, layered fluorine mica (synthetic mica), talc, mica and clay can be used. Of these, montmorillonite and / or layered fluorine mica (synthetic mica) is preferably used from the viewpoint of dimensional stability.

  The layered silicate (C) is optimally added at the time of polymerization of the polyamide 11 resin (A1a) and / or the polyamide 1010 resin (A1b). If this is difficult, the layered silicate is added before kneading. It is preferable to chemically modify (C) with a quaternary ammonium salt or a phosphonium salt.

  The content of the layered silicate (C) is preferably 0.1 to 45 parts by mass with respect to 100 parts by mass in total of the thermoplastic resin (A) and the glass fiber (B). If the content is less than 0.1 parts by mass, a sufficient effect may not be obtained. If the content exceeds 45 parts by mass, adverse effects such as poor fluidity during kneading / molding may be adversely affected. is there.

  The resin composition of the present invention may contain a plant-derived filler (D). By containing the plant-derived filler (D), the plant-derived degree can be kept high and the heat resistance of the molded product can be improved.

  Any plant-derived filler can be used as the plant-derived filler (D). As the form, any form such as a fibrous form or a powder form can be used. Specific examples of the fibrous material include jute fiber, kenaf fiber, bamboo fiber, hemp fiber, bagasse fiber, and the like, and specific examples of the powdered material include, for example, wood. Examples thereof include powder, bamboo powder, paper powder, and general cellulose powder.

  It is preferable to use a plant-derived filler (D) that has been delignified. Use of a material that has not been delignified may adversely affect the appearance or durability. The delignification treatment may be appropriately performed using a known method, but a method using a strong alkali solution such as a sodium hydroxide solution or a potassium hydroxide solution, a method of heating using sodium hydroxide and sodium sulfide, under acidic conditions, A method of treating with molybdate and hydrogen peroxide is exemplified. In addition to the delignification treatment, the coloration of lignin can be suppressed by further bleaching.

  It is preferable that content of a plant origin filler (D) is 5-200 mass parts with respect to a total of 100 mass parts of a thermoplastic resin (A) and glass fiber (B). When the content is less than 5 parts by mass, a sufficient heat resistance improvement effect may not be obtained, and the plant-derived ratio is also insufficient. When it mixes exceeding 200 mass parts, impact resistance may be reduced.

  A thermoplastic resin (A) such as a polyamide 11 resin (A1a) and / or a polyamide 1010 resin (A1b), a glass fiber (B) having a flat cross section, a layered silicate (C) or a plant-derived filler The means for mixing (D) is not particularly limited, and examples thereof include a melt kneading method using a uniaxial or biaxial extruder. In order to improve the kneading state, it is preferable to use a twin screw extruder. The kneading temperature ranges from (melting point of polyamide 11 resin (A1a) or / and polyamide 1010 resin (A1b) + 5 ° C.) to (melting point of polyamide 11 resin (A1a) or / and polyamide 1010 resin (A1b) + 100 ° C.), The kneading time is preferably 20 seconds to 30 minutes. If the temperature is lower or shorter than this range, the kneading or reaction may be insufficient. Conversely, if the temperature is higher or longer, the resin may be decomposed or colored. In order to achieve both flame retardancy and shape stability, a predetermined amount of glass fiber (B) is side-feeded and degassed under reduced pressure after sufficiently melting and mixing raw materials other than glass fiber (B). preferable.

  A flame retardant, a pigment, a heat stabilizer, an antioxidant, a weathering agent, a plasticizer, a lubricant, a release agent, an antistatic agent, and the like are added to the resin composition of the present invention as long as the characteristics are not significantly impaired. be able to. Although it does not specifically limit as a flame retardant, For example, a phosphorus flame retardant, a metal hydroxide, etc. are mentioned. Examples of heat stabilizers and antioxidants include hindered phenols, hindered amines, sulfur compounds, copper compounds, alkali metal halides, and the like. In addition, the method of mixing these with the thermoplastic resin composition of this invention is not specifically limited.

  The resin composition of the present invention can be formed into various molded products by molding methods such as injection molding, blow molding, extrusion molding, inflation molding, and vacuum molding, pressure molding, and vacuum / pressure molding after sheet processing. In particular, it is preferable to adopt an injection molding method, and in addition to a general injection molding method, gas injection molding, injection press molding, and the like can be employed. As an example of injection molding conditions suitable for the resin composition of the present invention, the cylinder temperature is not lower than the melting point or flow start temperature of the resin composition, preferably 190 to 270 ° C., and the mold temperature is (resin composition (Melting point of -20 ° C.) or less. If the molding temperature is too low, the operability becomes unstable, such as a short circuit occurring in the molded body, and it tends to be overloaded. On the other hand, if the molding temperature is too high, the resin composition is decomposed, and the strength of the resulting molded product is reduced, and problems such as coloring are likely to occur.

  Specific examples of molded products include: resin parts for electrical appliances such as various housings; agricultural materials such as containers and cultivation containers; resin parts for agricultural machinery; resin parts for marine products such as floats and processed fishery products containers; dishes; Tableware and food containers such as cups and spoons; Medical resin parts such as syringes and drip containers; Resin parts for drains, fences, storage boxes, construction switchboards, etc .; Cooler boxes, fan fans, toys Resin parts for miscellaneous goods such as leisure; automotive resin parts such as bumpers, instrument panels and door trims. Moreover, it can also be set as extrusion molded articles, such as a film, a sheet | seat, and a pipe, and a hollow molded article.

  Hereinafter, the present invention will be described more specifically with reference to examples. The materials and evaluation methods used in the following examples and comparative examples are as follows.

(1) Material [Thermoplastic resin (A)]
Polyamide 11 resin (A1a): Rilsan BMN O manufactured by Arkema
Polyamide 1010 resin (A1b): 100 parts by mass of sebacic acid (manufactured by Toyokuni Oil Co., Ltd.) was dissolved in hot methanol with stirring. Moreover, 85 parts by mass of decamethylenediamine (manufactured by Ogura Gosei Kogyo Co., Ltd.) was dissolved in methanol, and this was slowly added to the previous methanol solution of sebacic acid. After all of this was added, the mixture was stirred for about 15 minutes, the precipitate was filtered, and washed with methanol to obtain decamethylene diammonium sebacate.

  The autoclave was charged with 100 parts by mass of decamethylene diammonium sebacate and 33 parts by mass of water, and after substitution with nitrogen, heating was started while stirring at a preset temperature of 240 ° C. and 25 rpm. After the inside of the autoclave was maintained at a pressure of 2 MPa for 2 hours, the water vapor was exhausted to reduce the pressure to normal pressure. Subsequently, the mixture was stirred at normal pressure to 0.02 MPa for 2 to 3 hours, allowed to stand for 1 hour, and then discharged. And the polyamide 1010 was obtained by drying under reduced pressure.

・ Polyamide 66 resin: Unitika A142
Polylactic acid resin (A2): Terramac TE-4000 manufactured by Unitika
-Crosslinked polylactic acid resin (A2 '): Using a twin-screw extruder (TEM 37BS type manufactured by Toshiba Machine Co., Ltd.), 100 parts by mass of polylactic acid resin (A2) is supplied from the root supply port of the extruder, barrel temperature is 180 ° C, Extrusion was performed while venting was effected under the conditions of a screw speed of 280 rpm and a discharge rate of 15 kg / h. Furthermore, 0.10 parts by mass of ethylene glycol dimethacrylate and 0.2 parts by mass of perbutyl D (manufactured by NOF Corporation) as a peroxide were supplied into the cylinder. The resin discharged from the tip of the extruder was cut into pellets to obtain pellets of the resin composition. The obtained pellets were vacuum dried at 70 ° C. for 24 hours to obtain a crosslinked polylactic acid resin (A2 ′).

  -Modified polyolefin (A3a): Using a twin screw extruder (TEM37BS type manufactured by Toshiba Machine Co., Ltd.), 90 parts by weight of polyethylene and 10 parts by weight of maleic anhydride are fed from the root supply port of the extruder, barrel temperature is 180 ° C., screw Extrusion was carried out while venting under the conditions of a rotation speed of 280 rpm and a discharge rate of 15 kg / h. Further, 0.2 parts by mass of perbutyl D was supplied into the cylinder. The resin discharged from the tip of the extruder was cut into pellets to obtain pellets of the resin composition. The obtained pellets were vacuum-dried at 70 ° C. for 24 hours to obtain a modified polyolefin (A3a).

  -Modified polyolefin (A3b): Modified ethylene / α-olefin copolymer, Tuffmer TX1250, manufactured by Mitsui Chemicals, Inc.

[Glass fiber (B)]
-Flat cross-section glass fiber (B1): CSG3PA820S manufactured by Nitto Boseki Co., Ltd. (flat glass fiber having a flat cross-section with a major axis of 28 μm, a minor axis of 7 μm, and a major and minor axis ratio of 4.0)
-Circular cross-section glass fiber (B2): CS3J-451 manufactured by Nittobo Co., Ltd. (glass fiber having a circular cross section with a diameter of 10 μm and a length of 3 mm)

[Layered silicate (C)]
-Layered silicate (C): Shoben W manufactured by Hojun Co. (montmorillonite with interlayer ions substituted with dimethyldioctaldecylammonium ions)

[Plant-derived filler (D)]
-Kenaf fiber (D1): Kenaf cut to a fixed length of about 5 mm was pulverized and loosened with a turbo mill (T-250 manufactured by Matsubo) to give a diameter of 20 to 50 μm and a fiber length of 1 to 5 mm.

  -Kenaf fiber (D2): Lignin was removed by pressurizing and heating the kenaf fiber (D1) using a sodium hydroxide solution.

(2) Evaluation method (A) Flexural modulus: Measured according to ASTM D790. The flexural modulus is preferably 2.0 GPa or more.

  (B) Deflection temperature under load: Based on ASTM D648, the temperature at which heat deformation was performed with a load of 0.45 MPa was measured. The deflection temperature under load serves as an index of heat resistance, and is preferably 110 ° C. or higher.

  (C) Izod impact value: Measured according to ASTM D256-56. The Izod impact value is preferably 100 J / m or more.

  (D) Warpage amount: The test piece was allowed to stand on a horizontal plate, and the following four points were measured. The test piece used was a disc of 1.6 mm thickness and 100 mmφ. The amount of warpage is preferably 0.3 mm or less.

Warpage amount at reference point a, b: Warpage amount at two points touching the horizontal plate Warpage amount at warping point c, d: Warpage amount at two points with large warpage Warpage amount calculation formula: Warpage amount (mm) = (C + d) / 2- (a + b) / 2

  (E) Sink amount: A plate having a thickness of 4 × 6 inches (101.6 × 152.4 mm) × 10 mm was formed, and the depth of the portion where sink marks occurred was measured, and the average value was obtained.

  (F) Burr length: The mold temperature was set to 85 ° C., and the molded product was held at a holding pressure of 100 MPa until the molded product gate was completely cooled and solidified to obtain a molded product. The maximum burr length generated in the obtained molded product was measured to obtain the burr length.

  (G) Color tone: Using a Σ90 color measuring system manufactured by Nippon Denshoku Industries Co., Ltd., the L value of the resin composition pellet was measured with a C / 2 light source and reflection. The L value indicates lightness. The L value is preferably 30 or more.

Examples 5-6, Reference Examples 1-18 , Comparative Examples 2-7
Using a twin-screw extruder (Ikegai PCM30 type), the thermoplastic resin (A), layered silicate (C), and plant-derived filler (D) were dry blended and extruded in the proportions shown in Tables 1 and 2. The glass fiber (B) is supplied from the side supply port of the extruder at the ratio shown in Tables 1 and 2, and the barrel temperature is 240 ° C., the screw speed is 230 rpm, and the discharge amount is 5 kg / Extrusion was performed while venting was effective under the conditions of h. The resin discharged from the tip of the extruder was cut into pellets to obtain resin composition pellets.

  The obtained pellets were vacuum-dried at 90 ° C. for 24 hours, and then a test piece for measuring general physical properties (ASTM) while adjusting the mold surface temperature to 85 ° C. using an IS-80G injection molding machine manufactured by Toshiba Machine Co., Ltd. Mold) and prepared for various measurements. Separately, the above-described sink amount measurement plate was similarly formed, and the depth of sink was measured after cooling.

  The measurement results are shown in Tables 1 and 2.

Comparative Example 1
As shown in Table 2, using only the polyamide 11 resin pellets as the thermoplastic resin (A) and adjusting the mold surface temperature to 85 ° C. using an IS-80G injection molding machine manufactured by Toshiba Machine Co., Ltd. A test piece for general physical property measurement (ASTM type) was prepared and subjected to various measurements. Separately, the above-mentioned plate for sink measurement was similarly formed, and the depth of sink was measured after cooling.

  The measurement results are shown in Table 2.

As is clear from Table 1 and Table 2, in Examples 5 to 6 and Reference Examples 1 to 18 , resin compositions having a high ratio of plant-derived raw materials and excellent low warpage and rigidity were obtained.

In Examples 5 to 6 and Reference Examples 5 to 6 , since the polylactic acid resin (A2) (A2 ′) was blended, a molded product having a low degree of sink and high dimensional accuracy was obtained. In particular, Example 6 is superior in heat resistance compared to Example 5 using the non-crosslinked polylactic acid resin (A2) by using the crosslinked polylactic acid resin (A2 ′) as the polylactic acid resin (A2). A molded product was obtained. In Reference Example 5 , as in the other Examples and Reference Examples , the low warpage property was a sufficiently satisfactory level. However, since the blended amount of the crosslinked polylactic acid resin (A2 ′) was small, the effect of reducing sink marks was It was the same level as Reference Example 1 in which no lactic acid resin was blended. In Reference Example 6, since the amount of the crosslinked polylactic acid resin (A2 ′) was large, the degree of sink was small and extremely good, but the impact resistance was at a level lower than those of other Examples and Reference Examples. It was.

In Reference Examples 7 to 10, and 15 to 17 , since the modified polyolefin resins (A3a) and (A3b) were blended, molded articles having extremely excellent impact resistance were obtained. In particular, in Reference Examples 8 , 10 , and 15-17 , the modified polyolefin resin (A3b) composed of the modified ethylene / α-olefin copolymer was used in a sufficient amount, thereby providing impact resistance. Particularly excellent molded products were obtained. Reference Example 9 had a satisfactory level of low warpage as in the other Examples and Reference Examples , but since the amount of the modified polyolefin resin (A3b) was small, the impact resistance effect was improved. It was the same level as the reference example 1 which did not mix | blend.

Since the reference examples 11-14 mix | blended kenaf fiber as a plant origin filler (D), the molded article excellent in heat resistance was obtained. Furthermore, compared with Reference Example 11 using kenaf fiber (D1) not subjected to delignification treatment, Reference Examples 12 to 14 use kenaf fiber (D2) subjected to delignification treatment, and thus in the appearance of the molded product. More vivid and superior results were obtained.

In Reference Examples 15 to 17, since a predetermined amount of the layered silicate (C) was blended, generation of burrs during molding could be suppressed.

In Reference Example 18 , the polyamide 1010 resin (A1b) was used as the thermoplastic resin, but the same results as in Reference Example 3 above were obtained.

  From these results, by adding specific amounts of glass fiber, polylactic acid resin, modified polyolefin resin, layered silicate and kenaf fiber having a flat cross section to polyamide 11 resin and / or polyamide 1010 resin, the plant-derived degree is high, It was found that a resin composition having high rigidity, impact resistance and heat resistance, low warpage and low sinkability can be obtained.

In contrast to these Examples and Reference Examples , Comparative Example 1 was only economically disadvantageous because it used only the polyamide 11 resin alone. Since Comparative Example 2 used only a petroleum-derived polyamide 66 resin as a thermoplastic resin, Comparative Examples 3 and 4 had a small amount of polyamide 11 resin (A1a) and polyamide 1010 resin (A1b), Since the blending amount of the petroleum-derived polyamide 66 resin was so much, environmental considerations were not made. In Comparative Examples 2 to 6, the type of polyamide resin and glass fiber used, and the blending amounts thereof were not appropriate, so warpage was large. Since the comparative example 7 had too much compounding quantity of glass fiber, processing operativity was bad.

Claims (6)

Thermoplastic resin (A) 35-75 mass% and glass fiber (B) 25-65 mass% whose major axis / minor axis of the fiber cross section is 1.5-10, and containing thermoplastic resin (A) Part or all of them are polyamide 11 resin (A1a) or / and polyamide 1010 resin (A1b) and polylactic acid resin (A2) ,
Containing 10 parts by mass or more of polyamide 11 resin (A1a) and / or polyamide 1010 resin (A1b) with respect to a total of 100 parts by mass of the thermoplastic resin (A) and glass fiber (B) ,
A resin composition comprising 5 to 40 parts by mass of a polylactic acid resin (A2) with respect to 100 parts by mass in total of the thermoplastic resin (A) and the glass fiber (B) . Polylactic acid resin (A2) is a peroxide and / or (meth) resin composition according to claim 1, characterized in that it is cross-linked by the acrylic acid ester compound. Per 100 parts by weight of the thermoplastic resin (A) and glass fiber (B), according to claim 1 or 2, wherein the layered silicate and (C), characterized in that it contains 0.1 to 45 parts by weight Resin composition. Per 100 parts by weight of the thermoplastic resin (A) and glass fiber (B), any of the Claims 1 to 3 in which the plant-derived filler (D), characterized in that it contains 5 to 200 parts by weight The resin composition according to claim 1. The resin composition according to claim 4, wherein the plant-derived filler (D) is at least one selected from jute fiber, kenaf fiber, bamboo fiber, hemp fiber, and bagasse fiber. A molded article obtained by molding the resin composition according to any one of claims 1 to 5 .