JPH1087976A - Resin composition and molded product thereof - Google Patents

Abstract

[PROBLEMS] To perform injection molding at a mold temperature of Tg (glass transition temperature) or below or near room temperature (0 to 60 ° C.). The crystallization rate of the product is fast and the crystallinity is sufficient,
Provided is a heat-resistant resin composition having excellent heat resistance, and exhibiting a function that, when a molded product is used, a polymer component in the molded product is hardly deteriorated and a molded product is hardly embrittled. SOLUTION: As the polymer composition component (A), (a)
1) 75 to 25% by weight of polylactic acid, and (a2) 25 to 75% by weight of an aliphatic polyester having a melting point of 100 to 250 ° C. other than polylactic acid, and a crystalline inorganic filler component (B) 10% by weight of crystalline SiO ₂
Containing from above, and 0.1 to 70 parts by weight of component (B) based on 100 parts by weight of component (A).
Heat resistant resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polylactic acid resin composition and a molded product thereof. More specifically, the present invention relates to a polylactic acid resin composition having excellent heat resistance, impact resistance, and moldability, and having heat resistance to decompose in a natural environment after use, and a molded product thereof.

[0002]

[Prior art]

[Technical Background of General-Purpose Polymer] In general, resins such as polypropylene and crystalline polyethylene terephthalate (hereinafter referred to as PET) are examples of raw materials for containers having excellent heat resistance and impact resistance. However, when these resins are discarded after use, they increase the amount of refuse and are hardly decomposed in the natural environment. Therefore, even if they are buried, they remain semi-permanently in the ground. In addition, abandoned plastics cause problems such as degrading the landscape and destroying the living environment of marine life.

[Technical background of degradable polymer] On the other hand, as a biodegradable polymer made of a thermoplastic resin,
Polylactic acid, copolymers of polylactic acid with other aliphatic polyesters (hereinafter referred to as polylactic acid), polyesters derived from aliphatic polyhydric alcohols and aliphatic polycarboxylic acids, and the like have been developed. Some of these polymers include
100% biodegradable within several months to a year in animals
Alternatively, when placed in soil or seawater, in a humid environment, it may begin to decompose in a few weeks and disappear in about one to several years. Furthermore, the decomposition products have the property of becoming lactic acid, carbon dioxide, and water that are harmless to the human body.

[Technical background of polylactic acid] In recent years, polylactic acid has recently been produced in large quantities at low cost by fermentation using L-lactic acid as a raw material. It is expected to expand its field of use due to its excellent characteristics such as high strength. However, containers and packaging materials obtained by molding polylactic acid by ordinary injection molding or the like have the drawback that, although excellent in rigidity, they have low heat resistance. Therefore, polylactic acid is, for example, a container for pouring hot water, a container for use in a microwave oven, and the like.
It was not suitable for use at high temperatures.

[0005] [Conventional molding technology for imparting heat resistance to polylactic acid] Specific examples of the conventional technology for imparting heat resistance to polylactic acid are, for example, different from ordinary molding technology. A polylactic acid molded product is obtained by holding the product in the mold at the time of molding and keeping it at a temperature near Tc (crystallization temperature) for a long time without immediately taking out the product from the mold after molding. And a technique for highly post-crystallizing a polylactic acid molded article by subjecting the molded article to annealing treatment (heat treatment) after molding by a usual molding processing technique.

[Problems of conventional molding technology for imparting heat resistance to polylactic acid] The conventional molding technology for imparting heat resistance to polylactic acid has, for example, the following problems. . Unlike ordinary molding technology, the product is not taken out of the mold immediately after molding, and the product is kept in the mold after molding and takes a long time to reach a temperature near Tc (crystallization temperature). In a technique for highly crystallizing a polylactic acid molded product by holding the lactic acid, the crystallization may not always be sufficient, which is problematic. In the technology of highly post-crystallizing polylactic acid molded articles by annealing (heat treatment) the molded articles after molding by the usual molding processing technology, the molded articles may be deformed during the crystallization process. Yes, there was a problem.
Conventional molding technology for imparting heat resistance to polylactic acid, such as the above technology, requires special conditions in the process and is extremely long compared to general molding technology. The time required increases the production cost and is not always practical.

[Background of technology for imparting heat resistance to general-purpose polymer material] As a specific example of a technology for increasing the crystallization speed of a general-purpose polymer material, for example, a technology disclosed in Japanese Patent Application Laid-Open No. 60-86156 is disclosed. Can be mentioned. This technology is PE
Technology for adding finely divided wholly aromatic polyester powder containing terephthalic acid and resorcin as main constituent units as nucleating agents (additives for promoting crystallization, crystallization nucleating agents) to promote crystallization of T Is disclosed.

[Background of technology for imparting heat resistance to degradable polymer material] As a technology for imparting heat resistance to degradable polymer material, there is known a technology of adding a nucleating agent as in the case of general-purpose polymer material. ing. As a specific example, for example,
Japanese Patent No. 504731, U.S. Pat. No. 5,180,765, Japanese Translation of PCT International Publication No. 6-504799, and Japanese Patent Application Laid-Open No. 4-220456.

Japanese Patent Publication No. 4-5047731 (WO 9
No. 0/01521) Japanese Patent Publication No. 4-5047731 (WO 90/0152)
No. 1) discloses a technique for changing the properties of hardness, strength and temperature resistance by adding a filler of an inorganic compound such as silica or kaolinite to a lactide thermoplastic. In the example, a sheet having increased crystallinity was obtained by adding 5% by weight of calcium lactate as a nucleating agent to an L, DL-lactide copolymer and blending the mixture with a heating roll at 170 ° C. for 5 minutes. A manufacturing technique is disclosed. It is disclosed that this highly crystalline sheet has excellent rigidity and strength, but has low transparency and is cloudy. Thus, the present inventors have actually applied this technology to polylactic acid. That is, injection molding was attempted by adding silica, kaolinite, and talc to polylactic acid as nucleating agents. However, there are problems at least in the following two points, and a molded product that can withstand practical use could not be obtained. i) The crystallization rate was low and the degree of crystallization was insufficient. ii) The polymer component deteriorated and the molded product became brittle.

Japanese Unexamined Patent Publication No. 6-504799 (WO 9)
No. 2/04413) Tokuyohei Hei 6-504799 (WO 92/04413)
Discloses a technique of adding lactate or benzoate as a nucleating agent to a degradable polymer. In this example, a polylactide copolymer was blended with 1% calcium lactate as a nucleating agent, and a retention time of 2 minutes at about 85 ° C.
A technique is disclosed in which injection molding is performed using a mold held at a temperature of about 110 to 135 ° C. in a mold. Thus, the present inventors have actually applied this technology to polylactic acid. That is, injection molding was attempted by adding calcium lactate or sodium benzoate as a nucleating agent to polylactic acid. However, at least the following 2
However, there was a problem in that it was not possible to obtain a molded product that could withstand practical use. i) The crystallization rate was low and the degree of crystallization was insufficient. ii) The polymer component deteriorated and the molded product became brittle.

Japanese Patent Application Laid-Open No. Hei 4-220456 discloses a method in which polyglycolic acid and its derivative are added as a nucleating agent to poly-L-lactide, and the cooling mold temperature during injection molding is Tg ( Here, "T
"g" means glass transition temperature or glass transition point. The same applies hereinafter. A technique for increasing the crystallization rate, shortening the molding cycle time, and producing a molded article having excellent mechanical properties is disclosed. As an example of the injection molding, at a cooling time of 60 seconds, the crystallinity in the case where no nucleating agent is added is 22.6%, whereas in the case where the nucleating agent is added, it is 45.5%. It is disclosed. Thus, the present inventors have actually applied this technology to polylactic acid. That is, injection molding was attempted by adding polyglycolic acid as a nucleating agent to polylactic acid and raising the cooling mold temperature during injection molding to Tg or higher. However, molding was not possible under the condition that the mold temperature was equal to or higher than the Tg point.

JP-A-8-193165 (European Patent Publication 661346) The present inventors have already disclosed in JP-A-8-193165 (European Patent Publication 661346) crystalline poly-lactic acid as a nucleating agent for polylactic acid. A technique is disclosed in which a crystalline inorganic powder containing 50% or more of ₂ is mixed, melted, and molded while being crystallized. This technique is to provide a molded article having heat resistance, and is a very significant technique. However, this technique requires molding at a high mold temperature of 85 to 125 ° C. The present inventors have thought that it is necessary to further improve the productivity of this technology.

[0013] Problems of Conventional Techniques Contributing Heat Resistance to Degradable Polymer Materials by Adding Nucleating Agent As described above, in the case where heat resistance is to be imparted to polylactic acid, ordinary molding processing techniques (injection molding) Conventional nucleating agents (inorganic substances such as talc and silica, organic carboxylates, polymers, etc.) simply applied to conventional techniques for blow molding, compression molding, etc. However, there is a problem in that a molded product having high heat resistance (100 ° C. or higher) cannot be obtained.

[0014]

SUMMARY OF THE INVENTION The present invention provides a polylactic acid-based heat-resistant resin composition having excellent heat resistance and moldability, in addition to the excellent decomposability inherent to polylactic acid. It is an object to provide the molded product. INDUSTRIAL APPLICABILITY The present invention can be applied to a normal molding technology having high productivity, and can produce a molded product having excellent heat resistance and moldability, thereby producing a polylactic acid-based heat-resistant resin. It is an object to provide a composition.

[0015] Even when the present invention is applied to ordinary molding technology with high productivity, at least at the time of molding, the mold temperature is equal to or lower than Tg or near room temperature. For example, a temperature range of 0 to 60 ° C. is included. The same applies to the following.) During the molding process, the crystallization speed of the molded product is high,
The crystallinity is also sufficient, so the obtained molded product has excellent heat resistance, and when the molded product is used, the polymer component in the molded product is hardly deteriorated, and the molded product is also used. An object of the present invention is to provide a polylactic acid-based heat-resistant resin composition that exhibits a function of being hardly embrittled.

Here, the "ordinary molding technique with high productivity" is defined as "a special low-productivity molding technique such as heat treatment in a mold requiring a long molding cycle at a high mold temperature." Rather, it means normal molding technology with high productivity that requires only a short molding cycle at normal mold temperature. Also, "normal molding technology with high productivity"
Technology that uses a normal molding machine in a molding cycle equivalent to a general-purpose resin (for example, a molding cycle equivalent to a polypropylene resin) without using a special method such as annealing (heat treatment) in a mold. Also means.

Here, “excellent heat resistance” means that the molded product has a heat resistance temperature of 100 to 130 ° C. The term "excellent heat resistance" also means that the molded product is suitable for use at a high temperature, such as a container for pouring hot water. Further, “excellent heat resistance” also means that the molded product has a high degree of crystallinity.

[0018]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned "problem to be solved by the invention". As a result, polylactic acid has an aliphatic polyester having a melting point of 100 to 250 ° C. Even if the resin composition obtained by mixing the resin composition and the crystalline inorganic filler is injection-molded at a mold temperature of Tg or lower or at a temperature near room temperature, the crystallization speed of the molded product at the time of molding is high, and the degree of crystallinity is also high. It has been found that a molded article having sufficient heat resistance can be obtained, and the present invention has been completed. The invention according to the present application includes the following [1] to
[13] The invention according to [13].

[1] As the polymer composition component (A),
(A1) 75 to 25% by weight of polylactic acid, and (a2)
One containing 25 to 75% by weight of an aliphatic polyester having a melting point of 100 to 250 ° C. other than polylactic acid, and one crystalline SiO ₂ as a crystalline inorganic filler component (B).
0% by weight or more, and the component (A)
A heat-resistant resin composition, wherein component (B) is 0.1 to 70 parts by weight based on 100 parts by weight.

[2] The heat-resistant resin composition according to [1], wherein “(a1) polylactic acid” is a lactic acid homopolymer.

[3] “(a1) Polylactic acid” is (a)
1-1) Lactic acid homopolymer, (a1-2) Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid, (a1-3)
50% by weight or more of lactic acid, and 50% by weight or less of copolylactic acid produced from aliphatic polyhydric alcohol and aliphatic polybasic acid,
And (a1-4) selected from the group consisting of 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid and copolylactic acid produced from an aliphatic polyhydric alcohol and an aliphatic polybasic acid. Is at least one kind,
The heat-resistant resin composition according to [1].

[4] “(a1-2) Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid, (a1-3) 50% by weight or more of lactic acid, Copolylactic acid produced from 50% by weight or less of an aliphatic polyhydric alcohol and an aliphatic polybasic acid, and
(A1-4) 50% by weight or more of lactic acid and 50% by weight or less of lactic acid other than hydroxycarboxylic acid and copolylactic acid produced from aliphatic polyhydric alcohol and aliphatic polybasic acid "
Is a block copolymer, The heat-resistant resin composition according to [3].

[5] "(a1-2) Copolylactic acid formed from 50% by weight or more of lactic acid and 50% by weight or less of hydroxycarboxylic acid other than lactic acid", "hydroxycarboxylic acid other than lactic acid" is caproic acid The heat-resistant resin composition according to [3] or [4].

[6] "(a1-3) 50% by weight or more of lactic acid and 50% by weight or less of copolylactic acid produced from aliphatic polyhydric alcohol and aliphatic polybasic acid" The heat-resistant resin composition according to any one of [3] to [5], wherein the “aliphatic polybasic acid” is “1,4-butanediol and succinic acid”.

[7] "(a1-2) Copolylactic acid formed from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid" is represented by "(a1-2)
The heat-resistant resin composition according to [4], which is a block copolymer comprising a polylactic acid segment of 50% by weight or more and a polycaproic acid segment of 50% by weight or less.

[8] "(a1-3) Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of an aliphatic polyhydric alcohol and an aliphatic polybasic acid" is represented by "(a1-
3) The heat-resistant resin composition according to [4], which is a block copolymer comprising 50% by weight or more of a polylactic acid segment and 50% by weight or less of a polybutylene succinate segment.

[9] “(a2) Aliphatic polyester having a melting point of 100 to 250 ° C. other than polylactic acid” is (a2)
-1) polyethylene oxalate, (a2-2) polybutylene oxalate, (a2-3) polyneopentyl glycol oxalate, (a2-4) polyethylene succinate, (a2-5) polybutylene succinate, (a2) -6) polyglycolic acid, (a2-
7) Polyhydroxybutylic acid and (a)
2-8) The heat-resistant resin composition according to any one of [1] to [8], which is at least one selected from the group consisting of a copolymer of β-hydroxybutyric acid and β-hydroxyvaleric acid. .

[10] The heat-resistant resin according to any one of [1] to [8], wherein “(a2) an aliphatic polyester having a melting point of 100 to 250 ° C. other than polylactic acid” is a polybutylene succinate. Composition.

[11] “(a1) polylactic acid”
(A1-1) Lactic acid homopolymer, (a1-2) 50
Copolylactic acid produced from at least 50% by weight of lactic acid and at most 50% by weight of 6-hydroxycaproic acid; and (a1-
3) 50% by weight or more of lactic acid and 50% by weight or less of 1,
At least one selected from the group consisting of copolylactic acid formed from 4-butanediol and succinic acid,
The heat-resistant resin composition according to [1].

[12] At least one selected from the group consisting of talc, kaolin, clay and kaolinite, wherein “(B) a crystalline inorganic filler component containing 10% by weight or more of crystalline SiO ₂ ” One kind,
The heat-resistant resin composition according to any one of [1] to [11].

[13] The heat-resistant resin obtained from the heat-resistant resin composition according to any one of [1] to [12] has a heat-resistant temperature of 1
Molded product at 00 to 130 ° C.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the specification of the present application, when references are cited, all the descriptions are cited by explicitly indicating the cited references and cited ranges, unless otherwise specified. , And by referring to the explicitly cited scope, matters or disclosures that can be directly and uniquely derived by those skilled in the art in view of the matters or disclosures described in the specification of the present application.

[Polymer Composition Component] The polymer composition component (A) comprises (a1) 75 to 25% by weight of polylactic acid and (a2) an aliphatic polyester 25 other than polylactic acid.
About 75% by weight.

[Polylactic acid (a1)] The polylactic acid component (a1) used in the present invention includes polylactic acid, lactic acid-hydroxycarboxylic acid copolymer and lactic acid-aliphatic polyhydric alcohol-aliphatic polybasic acid copolymer. Copolylactic acid such as union, and polylactic acid and lactic acid-hydroxycarboxylic acid copolymer and lactic acid-
Polymer blends such as a mixture of an aliphatic polyhydric alcohol-aliphatic polybasic acid copolymer and a polymer alloy are included.

[Concept of the term "polylactic acid"] The term "polylactic acid" used in the present invention includes polylactic acid, lactic acid-hydroxycarboxylic acid copolymer and lactic acid-aliphatic polyhydric alcohol-fatty acid. Blends and polymers such as copolylactic acid such as aliphatic polybasic acid copolymer, and a mixture of polylactic acid and lactic acid-hydroxycarboxylic acid copolymer or lactic acid-aliphatic polyhydric alcohol-aliphatic polybasic acid copolymer Includes alloys. As raw materials for polylactic acid, lactic acids, hydroxycarboxylic acids, aliphatic polyhydric alcohols, aliphatic polybasic acids and the like are used.

[Lactic acid] Specific examples of the lactic acid include L-lactic acid, D-lactic acid, DL-lactic acid or a mixture thereof, or lactide which is a cyclic dimer of lactic acid.

[Hydroxycarboxylic acid] Specific examples of hydroxycarboxylic acids that can be used in combination with lactic acids include:
Glycolic acid, 3-hydroxybutyric acid, 4-hydroxybutyric acid, 4-hydroxyvaleric acid, 5-hydroxyvaleric acid, 6
-Hydroxycarboxylic acid, and further,
Hydroxycarboxylic acid cyclic ester intermediates, for example,
Examples include glycolide, which is a dimer of glycolic acid, and ε-caprolactone, which is a cyclic ester of 6-hydroxycaproic acid. These can be used alone or in combination of two or more.

[Aliphatic polyhydric alcohol] Specific examples of the aliphatic polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, and the like.
Polyethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4
-Butanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, neopentyl glycol, polytetramethylene glycol, 1,4-cyclohexanedimethanol,
4-benzenedimethanol and the like. They are,
They can be used alone or in combination of two or more.

[Aliphatic polybasic acid] Specific examples of the aliphatic polybasic acid include, for example, succinic acid, oxalic acid, malonic acid,
Examples include glutaric acid, adibic acid, bimeric acid, suberic acid, azelaic acid, sebacic acid, undecandioic acid dodecandioic acid, phenylsuccinic acid, and 1,4-phenylenone diacetic acid. These can be used alone or in combination of two or more.

[Method for Producing Polylactic Acid] Specific examples of the method for producing polylactic acid used in the present invention include, for example, a method of directly dehydrating polycondensation using lactic acid or a mixture of lactic acid and hydroxycarboxylic acid as a raw material ( For example, a production method disclosed in JP-A-6-65360), an indirect polymerization method in which a cyclic dimer of lactic acid (lactide) is melt-polymerized (for example, disclosed in US Pat. No. 2,758,987). Production method), a cyclic dimer of the lactic acid or hydroxycarboxylic acid, for example, lactide or glycolide, or ε-
A ring-opening polymerization method in which a cyclic ester intermediate such as caprolactone is melt-polymerized in the presence of a catalyst (U.S. Pat.
No. 7,537), and ring-opening polymerization using the same. The method for producing polylactic acid used in the present invention is not particularly limited. Also, aliphatic polyhydric alcohols such as glycerin, aliphatic polybasic acids such as butanetetracarboxylic acid, and polyhydric alcohols such as polysaccharides, and even when partially copolymerized, such as diisocyanates, etc. The molecular weight may be increased by using a suitable binder (polymer chain extender).

[Direct dehydration polycondensation method] In the case of producing by direct dehydration polycondensation, lactic acid or lactic acid and hydroxycarboxylic acid as raw materials are preferably azeotropically dehydrated in the presence of an organic solvent, particularly a phenyl ether solvent. Condensation, particularly preferably by removing the water from the solvent distilled off by azeotropic distillation and polymerizing the solvent in a substantially anhydrous state to the reaction system, to obtain a high-molecular-weight polymer having a strength suitable for the present invention. Lactic acid is obtained.

[Molecular Weight of Polylactic Acid] The weight average molecular weight (Mw) and molecular weight distribution of polylactic acid are not particularly limited as long as they can be substantially molded. The molecular weight of the polylactic acid used in the present invention is not particularly limited as long as it exhibits substantially sufficient mechanical properties. In general, the weight average molecular weight (Mw) is preferably from 10,000 to 500,000, and preferably from 3 to 500,000. ４０400,000 is more preferable, and 50,000 to 300,000 is further preferable. Generally, when the weight average molecular weight (Mw) is less than 10,000,
If the mechanical properties are not sufficient, or if the molecular weight exceeds 500,000, handling may be difficult or uneconomical.

[Embodiments of "polylactic acid"] The embodiments of polylactic acid that can be used in the present invention include the following:
And the like. Lactic acid homopolymer. Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of hydroxycarboxylic acid other than lactic acid. Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of an aliphatic polyhydric alcohol and an aliphatic polybasic acid. Copolylactic acid produced from 50% by weight or more of lactic acid, and 50% by weight or less of carboxylic acid other than lactic acid and aliphatic polyhydric alcohol and aliphatic polybasic acid. Here, copolylactic acid is a random copolymer,
It may be a block polymer or a mixture of both.

[Embodiments of "copolylactic acid"] Examples of the copolylactic acid that can be preferably used in the present invention include the following.

50% by weight or more of lactic acid and 50% by weight
A lactic acid block copolymer produced from the following caproic acid.

50% by weight or more of lactic acid and 50% by weight
A lactic acid block copolymer produced from the following 1,4-butanediol and succinic acid.

A block copolymer comprising 50% by weight or more of a polylactic acid segment and 50% by weight or less of a polycaproic acid segment.

A block copolymer comprising 50% by weight or more of a polylactic acid segment and 50% by weight or less of a polybutylene succinate segment. In the present invention, as the polylactic acid, a lactic acid homopolymer, a block copolymer having a polylactic acid segment and a polybutylene succinate segment and / or a polycaproic acid segment can be particularly preferably used. The polylactic acid of these embodiments can be used alone or in any combination of two or more. In the present invention, the content of the lactic acid component in the monomer system when polymerizing polylactic acid is at least 50% by weight, preferably at least 60% by weight, more preferably at least 70% by weight, and at least 80% by weight. More preferred.

[Aliphatic polyester component (a2)] Specific examples of the aliphatic polyester component (a2) used in the present invention include, for example, the above-mentioned condensates of aliphatic hydroxycarboxylic acids and aliphatic dihydric alcohols. Dehydration condensates obtained by variously combining aliphatic polybasic acids such as aliphatic polyhydric alcohols and aliphatic dibasic acids;
It is not particularly limited as long as it is an aliphatic polyester having a melting point of Usually, those having crystallinity and biodegradability are particularly preferable. For example, a dehydration condensate of an aliphatic polyhydric alcohol and an aliphatic polybasic acid, a condensate of a hydroxycarboxylic acid, and the like are included. More specific examples of the aliphatic polyester component (a2) used in the present invention include, for example, polyethylene oxalate, polyethylene succinate, polybutylene oxalate, polyneopenylene glycol oxalate, polyethylene succinate,
Polybutylene succinate, polyglycolic acid, polyhydroxybutyric acid, and copolymers of β-hydroxybutyric acid and β-hydroxyvaleric acid, and the like. Among these, polyethylene succinate, and polybutylene oxalate are particularly preferable. As a method for producing the aliphatic polyester component (a2), the above-described method for producing polylactic acid can be employed. The weight average molecular weight (Mw) of these aliphatic polyester components (a2) is usually from 1 to 1,000,000, preferably from 30,000 to 500,000, and more preferably from 50,000 to 300,000. These polyesters may have a polymer chain extended by a binder such as diisocyanate.

In the resin composition according to the present invention, the aliphatic polyester component (a2), together with the crystalline inorganic filler described later, is used to prepare the polymer composition component (A) at a mold temperature of T.
g or below room temperature, and plays a role in promoting crystallization when molding.
Aliphatic polyester having a melting point lower than ℃ does not have the effect, or even if it has the effect, when the mold temperature is Tg or less, or at the time of injection molding near room temperature, the effect is sufficient May not be. Further, the heat-resistant temperature of the obtained molded product may be lower than 100 ° C., and the object of the present invention may not be achieved.

In the resin composition according to the present invention, it is important that the aliphatic polyester component (a2) is contained at 25 to 75% by weight in the polymer composition component (A). If the content is less than 25%, the cooling time during injection molding becomes longer, so that the molding cycle becomes longer and the productivity becomes worse, or under normal molding conditions,
In some cases, the crystallization speed is low, and sufficient heat resistance cannot be exhibited.

In the resin composition according to the present invention, it is important that the polymer composition component (A) contains 25 to 75% by weight of a lactic acid component. If the lactic acid component exceeds 75% by weight, the cooling time during injection molding becomes longer, which may result in a longer molding cycle and lower productivity. Further, the obtained molded product has low heat resistance (Vicat softening point is about 60 ° C.), and it is difficult to obtain a molded product excellent in heat resistance which is the object of the present invention. vice versa,
When the lactic acid component is less than 25% by weight, for example,
When formed into a molded product that comes into contact with food such as tableware and trays, the resulting molded product may have reduced hygiene performance such as mold resistance, and furthermore, biodegradability in compost May also decrease.

[Crystalline Inorganic Filler Component] In the present invention, a crystalline inorganic filler is added for the purpose of shortening the molding cycle during molding and accelerating the crystallization speed. The crystalline inorganic filler component (B) comprises (b1) 10 crystalline SiO ₂
% Or more, and (b2) those containing 90% by weight or less of a crystalline inorganic filler other than crystalline SiO ₂ . The crystalline inorganic filler component (B) comprises (b1)
10% by weight or more of crystalline SiO ₂ and (b2)
It may be talc, kaolin, clay or kaolinite, which satisfies the condition containing 90% by weight or less of a crystalline inorganic filler other than crystalline SiO ₂ . These can be used alone or in combination. The SiO ₂ content in the crystalline inorganic filler component is preferably 10% by weight or more, more preferably 20% by weight or more, still more preferably 30% by weight or more, still more preferably 40% by weight or more.
0% by weight or more is more preferable. The pH of the crystalline inorganic filler component is not particularly limited, but is generally in the range of 3.0 to 10.0 in order to prevent a decrease in molecular weight due to thermal deterioration during processing of polylactic acid and a decrease in strength accompanying the degradation. The range is preferably 3.5 to 9.0, more preferably 4.0 to 9.0.
A range of 8.0 is more preferred.

[Weight ratio of polymer composition component and crystalline inorganic filler component] In the heat resistant resin composition according to the present invention,
The weight ratio of component (A) to component (B) is 100% for component (A).
Component (B) is 0.1 to 70 parts by weight, preferably 5 to 65 parts by weight, more preferably 10 to 60 parts by weight, and even more preferably 20 to 50 parts by weight with respect to parts by weight. If the amount of the crystalline inorganic filler component is small, the added effect (the effect of promoting the crystallization rate) is low, and if it is large, molding becomes difficult or the molecular weight of the polymer composition component is reduced, and the As a result, short-term and long-term mechanical properties may have unfavorable stability.

[Production Method of Resin Composition] The production method of the resin composition is not particularly limited, and a known method usually used for a thermoplastic resin can be employed.
The polymer composition component (A), the crystalline inorganic filler component (B), and, if necessary, the third component (C) are uniformly mixed using a high-speed stirrer or a low-speed stirrer, and then sufficiently kneaded. A method of melt-kneading with a capable single-screw or multi-screw extruder can be adopted. In the present invention, the production of the polymer composition component (A) may be carried out by a known kneading technique, for example, mixing the raw materials in a solid state with a Henschel mixer, a ribbon blender, or the like, or further using an extruder or the like. And a method of kneading while melting. Various stabilizers, ultraviolet absorbers, flame retardants, internal mold release agents, lubricants, plasticizers, inorganic fillers, and the like can be added to the resin composition according to the present invention according to the purpose. In particular, it is recommended to add an internal release agent for the purpose of further improving the moldability, which is one of the objects of the present invention. Examples of the release agent used in the present invention include release agents such as ordinary higher fatty acids and their salts and ester oils, silicone oils, polyvinyl alcohols, polyalkyl glycols, and low molecular weight polyolefins. preferable. Specific examples of the silicone oil include straight silicone oils such as dimethyl silicone oil, methyl hydrogen silicone oil, methylphenyl silicone oil, cyclic dimethyl silicone oil, etc., polyether-modified silicone oil, methylstyryl-modified silicone oil, and alkyl-modified silicone oil. Modified silicone oils such as silicone oil, higher fatty acid ester-modified silicone oil, hydrophilic specially modified silicone oil, and higher fatty acid-containing silicone oil are included.Dimethyl silicone oil, methylphenyl silicone oil, and cyclic dimethyl silicone are particularly preferred in terms of safety. Oil is preferred. Usually, the shape of the resin composition according to the present invention is preferably a pellet, a rod, a powder, or the like. The resin composition according to the present invention can be homogenized by a mixer and subjected to injection molding, blow molding, compression molding and the like under ordinary molding conditions.

[Molding] The resin composition according to the present invention comprises:
It is a material suitable for molding processes such as injection molding, extrusion molding, calendar molding, blow molding, balloon molding and the like. The resin composition according to the present invention can be used in a molding machine with a molding cycle equivalent to that of a general-purpose resin (for example, equivalent to polypropylene resin) without using a special technique such as annealing (heat treatment) in a mold. ), A molded product can be easily obtained.

The resin composition according to the present invention is a material suitable for molding processes such as injection molding, extrusion molding, blow molding, vacuum molding, vacuum pressure molding, calendar molding, balloon molding and the like. The resin composition according to the present invention can be produced in a molding machine at a molding cycle equivalent to that of a general-purpose resin without using a special method such as annealing treatment (heat treatment) in a mold (for example, with a polypropylene resin). In the same molding cycle), a molded product can be easily obtained. Hereinafter, a method for manufacturing a heat-resistant molded product according to the present invention will be described.

Injection Molding In injection molding, pellets of the resin composition according to the present invention are melt-softened, filled in a mold maintained at room temperature (0 to 60 ° C.), and molded in a molding cycle of 20 to 35 seconds. Things are obtained. The obtained molded product has a Vicat softening point of 100
~ 130 ° C and has excellent heat resistance. Extrusion Molding In extrusion molding, a heat-resistant film or sheet can be molded by molding the resin composition according to the present invention with a general T-die extruder.

Blow Molding (Injection Blow Molding, Stretch Blow Molding, Direct Blow Molding) For example, in injection blow molding, pellets of the resin composition according to the present invention are melted with a general injection blow molding machine and then molded. To obtain a preform. After reheating the obtained preformed body in an oven (heating furnace), the preformed body is placed in a mold maintained at room temperature (0 to 60 ° C.), and blown by sending out pressurized air. Blow bottles having the desired heat resistance can be molded.

Vacuum forming / vacuum pressure forming A film or sheet formed by the same method as described above is used as a preform. After heating and temporarily softening the obtained pre-formed body, vacuum forming or vacuum forming is performed using a general vacuum forming machine in a mold maintained at room temperature (0 to 60 ° C.). By performing air pressure molding, a molded article having heat resistance which is the object of the present invention can be molded.

[Use] The resin composition according to the present invention is suitably used as a substitute for a resin used for medical use, food packaging and general use which was known and used before the present application. Can be. Moreover, since the heat-resistant temperature of the molded article made of the resin composition according to the present invention is 100 to 130 ° C, it is also suitable for heat-resistant containers (eg, sterilization containers, containers for pouring hot water, containers for retorts, etc.). Can be used for Further, the resin composition according to the present invention, for example, ballpoint pen
Materials for writing utensils such as mechanical pencils and pencils, materials for stationery, materials for golf tees, materials for smoked golf balls for starting balls, capsules for oral medicine, carriers for anal and vaginal suppositories, carriers for patches for skin and mucous membranes, Capsules for pesticides, capsules for fertilizer, capsules for seeds and seedlings, compost, fishing line spools, fishing floats, bait for fishing, lures, buoys for fishing,
Hunting decoys, hunting shot capsules, tableware and other camping equipment, nails, piles, binding materials, muddy / slippery materials for snowy roads,
It can be suitably used as a block or the like. The resin composition according to the present invention can be produced by a suitable molding method, for example, a lunch box, tableware, a lunch box or a side dish container sold at a convenience store, chopsticks, split chopsticks, fork, spoon, skewer, toothpick, cup, etc. Ramen cups, cups used in beverage vending machines, fresh fish, meat,
Containers and trays for foodstuffs such as fruits and vegetables, tofu, and prepared foods, bottles and cans for dairy products such as torobaco, milk, yogurt, and lactic acid bacteria drinks used in the fresh fish market, and soft drinks such as carbonated beverages and soft drinks Bottles and cans for liquor drinks such as beer and whiskey, bottles with or without pumps for shampoo and liquid soap, tubes for toothpaste, cosmetic containers, detergent containers, bleach containers, cool boxes, Flower pots, casings for water purifier cartridges, casings for artificial kidneys and artificial livers, syringe barrels, cushioning materials for transporting home appliances such as TVs and stereos, and precision machinery such as computers, printers and clocks. Buffer material for use in transportation, buffer material for use in transporting optical machines such as cameras, glasses, microscopes, telescopes, etc., glass and ceramic It can be suitably used as a cushioning material for use in transportation of ceramic products vessels like.

[Concept of the word "resin"] The concept of the term "resin" used in the specification of the present application is "synthetic resin",
The term includes the concept of the term “plastic”, “plastic or plastic polymer”, or “polymer other than fiber and rubber”.

[Concept of the term “polymer”] The concept of the term “polymer” used in the specification of the present application is “polymer”,
The terms "polymer,""macromolecule," or "macromolecule" are mutually equivalent and include homopolymers and copolymers. The term "copolymer" as used in the specification of the present application is mutually equivalent to the term "copolymer". The mode of arrangement of the copolymer (copolymer) may be any of a random copolymer, an alternating copolymer, a block copolymer, a graft copolymer and the like. The polymer is
Any of linear, macrocyclic, branched, star, ladder, three-dimensional mesh, and the like may be used.

[Concept of the word "resin composition"] The concept of the term "resin composition" used in the specification of the present application includes a composition containing a polymer composition component and components of other substances. I do. The concept of the term “resin composition” used in the specification of the present application refers to (A) a polymer composition component and (B)
Includes compositions containing a crystalline inorganic filler component and, optionally, a third component (C).

[Concept of the term "polymer composition"] The concept of the term "polymer composition" used in the specification of the present application is as follows.
Includes compositions comprising one or more macromolecules and one or more low molecular weight compounds. The term “polymer composition” as used in the specification of the present application includes a composition containing two or more polymers. The term “polymer composition” as used in the specification of the present application includes a composition containing two or more polymers and one or more low-molecular compounds.
As used in the specification of the present application, the term “polymer composition” refers to a polymer mixture containing two or more polymers,
Includes polymer alloys and polymer blends. The term “polymer composition” as used in the specification of the present application includes those containing a compatible agent in order to achieve compatibility of two or more polymers.

[Concept of the word "degradable"] The concept of the term "degradable" used in the specification of the present application includes, for an organic material, a period of time used for a specific purpose, and a material suitable for the purpose. It also includes the function of retaining its properties and weakening and detoxifying it in a natural environment or in an in vivo environment after the end of its purpose or after disposal. The concept of the term “degradable” used in the specification of the present application includes, for example, “New Edition Polymer Dictionary (edited by The Society of Polymer Science, Asakura Shoten, Tokyo, 1988)”.
-The concept of "disintegration" described in the section "Disintegrable polymer" in the right column on page 424 to the left column on page 425 is also included. The concept of the term “degradable” used in the specification of the present application includes, for example, “Photodisintegrable” in “New Edition Polymer Dictionary (edited by The Society of Polymer Science, Asakura Shoten, Tokyo, 1988)” on page 369, left column. "", The concept of "photodegradability". The concept of the term “degradable” used in the specification of the present application includes, for example, “MARUZEN High Polymer Dictionary-
Concise Encyclopedia of P
oligomer Science and Engineering
ering (edited by Kroschwitz, translated by Tatsuta Mita,
Maruzen, Tokyo, 1994) "539, left column to page 540, right column," biodegradable polymer ". The concept of "degradable" as used in the specification of the present application also includes the concept of "composable". The evaluation of "degradability" includes, for example, an embedding test in soil, a decomposition test using a cultured microorganism, a decomposition test using an enzyme preparation, an in-vitro decomposition test in serum, and an in-vivo decomposition test using in vivo implantation. , Light irradiation test, etc., and more specifically, for example, AST
MD5209-91 (biodegradability test) and ASTM D
5338-92 (compostability (soil regression performance) test).

"Degradability" used in the specification of the present application
The concept of the term includes the concept of the word "biodegradable". The term "biodegradable" as used in the specification of the present application includes a property that is naturally degraded in a natural environment (in an environment such as soil, in the sea, in a river, etc.).

[Concept of the word "heat resistance"] In the specification of the present application, "heat resistance" means that a molded product is 100 to 13
It has a heat resistance temperature of 0 ° C. The term "heat resistance" also includes that the molded product is suitable for use at a high temperature, such as a container for pouring hot water. The term “heat resistance” also means that a molded product has a high degree of crystallinity. The molded product obtained by applying the resin composition according to the present invention to each molding machine is (A)
A polymer composition component, (B) a crystalline inorganic filler component,
(C) Generally, it has a heat resistant temperature of 100 to 130 ° C., although it depends on the type of the third component (various modifiers and the like), the amount added, and the like. In the present invention, the heat-resistant temperature means "Vicat softening point". A method for evaluating the “Vicat softening point” is disclosed in ASTM-D1525. In this evaluation method, a cylindrical needle having a diameter of 1 mmφ is placed on a sample,
When the temperature was raised with a load of 1 kg,
The temperature when the needle enters the sample by 1 mm. The resin composition according to the present invention can be efficiently molded with a general-purpose molding machine for molding a general-purpose resin such as a polypropylene resin, and the obtained molded product is suitably used for various applications from daily necessities to sundries. And especially excellent heat resistance,
For example, it can be suitably used for a container for pouring boiling water.

[Concept of "Compatibilizer"] The term "compatibilizer" used in the specification of the present application is interchangeable with the concept of "compatibilizer" or "compatibilizer". For example, "New Edition Polymer Dictionary (edited by the Society of Polymer Science, Asakura Shoten, Tokyo, 1988)", p.
Includes the concept of "compatibilizer" or "compatibilizer" described in the section "Polymer blend" on the right column on page 438, and is added in a small amount to an incompatible or low-compatible multi-phase polymer. By doing so, it also means a third component that improves compatibility and enables significant improvement in material properties. The concept of the term "compatibilizer" used in the specification of the present application is described, for example, in "Polymer Alloy-Basics and Applications-(edited by The Society of Polymer Science, Tokyo Kagaku Dojin, Tokyo, 1981)". It also includes the concept of "compatibilizer", "compatibilizer" or "compatibility".

[Concept of the word "polymer blend"] The concept of the term "polymer blend" used in the specification of the present application includes, for example, "New Polymer Dictionary (edited by the Society of Polymer Science,
Asakura Shoten, Tokyo, 1988) ", page 437, left column-43
The term “polymer blend” on the right column on page 8 and the concept of polymer blend described in “Polymer Alloy-Fundamentals and Applications-(edited by the Society of Polymer Science, Tokyo Kagaku Dojin, Tokyo, 1981)” are also included. It also means a polymer material made by mixing different kinds of polymers.

[Concept of the word "polymer alloy"] The concept of the term "polymer alloy" used in the specification of the present application includes, for example, "New Polymer Dictionary (Polymer Society, edited by The Society of Polymer Science, Asakura Shoten, Tokyo, 1988). ) ”, Page 435,“ Polymer alloy ”and the concept of polymer alloy described in“ Polymer alloy-basics and applications-(edited by The Society of Polymer Science, Tokyo Kagaku Dojin, Tokyo, 1981) ”. , Block copolymers, graft copolymers, physical polymer blends (melt blends, solvent cast blends, latex blends, etc.), polymer complexes (ionomers, polyion complexes, etc.), chemical polymer blends (solution grafts, IPNs, etc.) Includes polymeric multi-component systems.

[0072]

EXAMPLES The present invention will be specifically described below with reference to examples. The methods for measuring the weight average molecular weight (Mw) and heat resistance (Vicat softening point) of polylactic acid were measured by the following methods. Weight average molecular weight (Mw) Measured by gel permeation chromatography (GPC, column temperature 40 ° C, chloroform solvent) using polystyrene as a standard. Vicat softening point Vicat softening temperature (Vicat softening point) (ASTM-D1525) was used as an index of heat resistance of a molded product, with a load of 1
The test piece after molding was measured under the condition of kg.

Evaluation of Mold Resistance A test piece of 5 cm × 5 cm was placed on a medium which had been sterilized and solidified beforehand, and sprayed with a spore suspension of the following test bacterium.
The cells were cultured in a thermostat at 0 ° C. for 6 months, and the growth of the mold was observed and evaluated. <Test Bacteria> Aspergillus niger Rhizopus oryzae Penicillium citrinium Cladosporium cladosporioi
des Chaetomium globosum <Medium> Inorganic salt agar medium (prepared according to JIS Z-2911) Ammonium nitrate 3.0 g Potassium phosphate 1.0 g Magnesium sulfate 0.5 g Potassium chloride 0.25 g Ferrous sulfate 0.002 g Agar 25 g Purified water 1,000 ml <Evaluation> After completion of the culture, the growth of the mold was evaluated with the following circles. ：: No mold growth was observed. Δ: Mold growth area is 1/3 or less. ×: Mold growth area is more than 1/3.

Evaluation of Degradability A pressed film having a thickness of 100 μm and a size of 10 cm × 30 cm was prepared and buried in a compost having a temperature of 58 ° C. and a water content of 60% by weight (components: rice husk, garbage, chicken manure, human waste, etc.) Changes over time were observed. A: Eliminated within 7 days. ；: Eliminated in 7-14 days. Δ: Dissolved in 15 to 25 days. ×: Dissolved in 26 to 40 days.

[Production Example 1] 400 g of L-latatatide, 0.04 g of stannous octoate and 0.12 g of lauryl alcohol were sealed in a thick-walled cylindrical stainless-steel polymerization vessel equipped with a stirrer, and vacuumed. After degassing for 2 hours and replacing with nitrogen gas, the mixture was heated and stirred at 200 ° C./10 mmHg for 2 hours. After the completion of the reaction, the melt of polylactic acid was extracted from the lower outlet, air-cooled, and cut with a pelletizer. The resulting polylactic acid had a yield of 340 g, a yield of 85%,
The weight average molecular weight (Mw) was 138,000.

[Production Example 2] A reactor equipped with a Dien-Stark trap was charged with 10 kg of 90% L-lactic acid and 45 g of tin dust, and water was distilled while stirring at 150 ° C / 50 mmHg for 3 hours. Thereafter, the mixture was stirred at 150 ° C./30 mmHg for another 2 hours to be oligomerized. 21.1 kg of diphenyl ether was added to this oligomer,
/ 35 mmHg azeotropic dehydration reaction was performed, and the distilled water and the solvent were separated by a water separator, and only the solvent was returned to the reactor. Two hours later, the organic solvent to be returned to the reactor was passed through a column packed with 4.6 kg of molecular sieve 3A, and then returned to the reactor. The reaction was carried out at 150 ° C./35 mmHg for 40 hours, and the weight average molecular weight (Mw) was 14. 50,000 polylactic acid solutions were obtained. 44 kg of dehydrated diphenyl ether in this solution
After cooling, the mixture was cooled to 40 ° C., and the precipitated crystals were filtered off and washed with 10 kg of n-hexane three times to give 60 ml.
C./50 mmHg. This powder is 0.5N-H
After adding 12 kg of Cl and 12 kg of ethanol, the mixture was stirred at 35 ° C. for 1 hour, filtered, and dried at 60 ° C./50 mmHg to obtain 6.1 kg of polylactic acid powder (yield: 85%).
This powder was melted and pelletized by an extruder to obtain polylactic acid. The weight average molecular weight (Mw) of this polymer is 14.3
It was 10,000.

[Production Example 3] 1,4-Butanediol was placed in a reactor equipped with a Dien-Stark trap.
5 kg, 66.5 kg of succinic acid and 45 g of tin powder are charged,
After distilling water while stirring at 100 ° C. for 3 hours, 15
The mixture was stirred at 0 ° C./50 mmHg for another 2 hours to be oligomerized. This oligomer has diphenyl ether 385k
g was added thereto, and an azeotropic dehydration reaction at 150 ° C./35 mmHg was performed. Distilled water and the solvent were separated by a water separator, and only the solvent was returned to the reactor. After 2 hours, return 5 parts of organic solvent to the reactor.
After passing through a column packed with 0 kg molecular sieve 3A and returning to the reactor, 130 ° C./17 mmHg
For 15 hours and a weight average molecular weight (Mw) of 14.0.
Ten thousand polybutylene succinate (hereinafter, referred to as PSB) solutions were obtained. To this solution was added 160 kg of dehydrated diphenyl ether, diluted, cooled to 40 ° C., and the precipitated crystals were filtered. 0.5N-
Add 200 kg of HCl and 200 kg of ethanol and add 2
After stirring at 5 ° C for 1 hour, the mixture was filtered, and the mixture was filtered at 60 ° C / 50 mmH.
Then, 91.5 kg of PSB (94.8% yield) was obtained. The weight average molecular weight (Mw) of this polymer is 13.
It was 80,000.

Next, in the same manner as in Production Example 2, one hour after the reaction solvent was started to pass through the molecular sieve 3A,
The reaction mass of the obtained polylactic acid having a weight average molecular weight (Mw) of 21,000 (750 g of polylactic acid, diphenyl ether 22
50.0 g) and the weight average molecular weight (Mw) of 13.8.
Charge 187.5 g of polybutylene succinate,
Further, the reaction was carried out at 130 ° C./17 mmHg for 20 hours. After 3,000 g of diphenyl ether was added to the obtained reaction solution for dilution, the reaction solution was cooled to 40 ° C., and the precipitated crystals were filtered. To the crystals, 2,000 g of 0.5N HCl and 2000 g of ethanol were added, and the mixture was stirred at 25 ° C. for 1 hour, filtered, dried at 60 ° C./50 mmHg, and a block copolymer of polylactic acid and PSB (lactic acid component 80 Weight%) 8
90 g (94.9% yield) was obtained. The weight average molecular weight (Mw) of this copolymer was 146,000.

[Production Example 4] 6-hydroxycaproic acid 11 was placed in a reactor equipped with a Dien-Stark trap.
After 1 kg and 45 g of tin powder were charged, water was distilled off while stirring at 100 ° C. for 3 hours, and the mixture was further stirred at 150 ° C./50 mmHg for 2 hours to oligomerize. 385 kg of diphenyl ether is added to this oligomer,
An azeotropic dehydration reaction of 5 mmHg was performed, and the distilled water and the solvent were separated by a water separator, and only the solvent was returned to the reactor. Two hours later, the organic solvent to be returned to the reactor was passed through a column packed with 50 kg of molecular sieve 3A, and then returned to the reactor. The reaction was carried out at 130 ° C./17 mmHg for 15 hours, and the weight average molecular weight (Mw) was 11,000,000. (Hereinafter, referred to as PCL) solution was obtained. 160 kg of dehydrated diphenyl ether is added to this solution, and after dilution, 40 kg is added.
After cooling to ℃, the precipitated crystals were filtered. 200 kg of 0.5 N HCl and 200 kg of ethanol
After stirring at 25 ° C. for 1 hour, the mixture was filtered,
It dried at 50 degreeC / 50 mmHg, and obtained 92.4 kg of PCL (96.0% of yield). The weight average molecular weight (Mw) of this polymer was 104,000.

Next, in the same manner as in Production Example 3, one hour after the reaction solvent was started to pass through the molecular sieve 3A,
The reaction mass of the obtained polylactic acid having a weight average molecular weight (Mw) of 21,000 (750 g of polylactic acid, diphenyl ether 22
50.0 g) and the weight average molecular weight (Mw) 10.4
Of polycaproic acid (187.5 g) and 13
The reaction was carried out at 0 ° C./17 mmHg for 20 hours. After 3,000 g of diphenyl ether was added to the obtained reaction solution for dilution, the reaction solution was cooled to 40 ° C., and the precipitated crystals were filtered. To the crystals, 2,000 g of 0.5N HCl and 2000 g of ethanol were added, and the mixture was stirred at 25 ° C. for 1 hour, filtered, dried at 60 ° C./50 mmHg, and polylactic acid and PCL were added.
Block copolymer (lactic acid component 80% by weight) 879.4
g (93.8% yield). The weight average molecular weight (Mw) of this copolymer was 132,000.

Hereinafter, examples of the method for producing the heat-resistant resin composition according to the present invention using the polylactic acid obtained in Production Examples 1 to 4 will be described.

[Examples 1 to 12] Polylactic acid (polylactic acid, block copolymer of polylactic acid and polybutylene succinate, block copolymer of polylactic acid and polycaproic acid) obtained in Production Examples 1 to 4, polybutylene After mixing the succinate (melting point = 110 ° C) and the inorganic filler in the ratio shown in Table 1 [Table 1 and Table 2] using a Henschel mixer, the extruder cylinder temperature was set to 170 to 210 ° C. Pelletized. The pellets were set at a cylinder setting temperature of 180-200 JSW-75 injection molding machine manufactured by Japan Steel Works, Ltd.
Melting was performed at 200 ° C., test pieces for ASTM physical properties were prepared at the mold temperature and cooling time shown in the table, and the heat resistance of the obtained test pieces was evaluated. The results are shown in Table 1 [Table 1 and Table 2].

[Comparative Examples 1 to 12] Polylactic acid, polybutylene succinate (melting point = 110 ° C) and inorganic fillers were listed in Table 1.
2 Performed in the same manner as in the examples at the ratios shown in Tables 3 to 5. The results are shown in Table 2 [Tables 3 to 5].

[Legend of description in table] PSB: Polybutylene succinate Vicat softening point measurement conditions: Weight: 1,000 g Kaolin JP100: NN Kaolin Clay made by Tsuchiya Kaolin Co., Ltd .: Kaori made by Tsuchiya Kaolin Knight ASP-170: Kaolin UW manufactured by Fuji Talc Co., Ltd. Talc TM-30 manufactured by Engelhard Co., Ltd. Talc RF manufactured by Fuji Talc Co., Ltd .: Siloid 244 manufactured by Fuji Talc Co., Ltd .: Fuji Silysia Chemical Co., Ltd. Aerosil 200 manufactured by Aerosil Co., Ltd. Table 1 [Table 1] shows the compositions of Examples 1 to 5, molding conditions,
The evaluation of the molded product was shown. Table 1 (continued) [Table 2] shows the compositions, molding conditions, and evaluations of the molded products of Examples 6 to 11. Table 2 [Table 3] shows the compositions, molding conditions, and evaluations of the molded products of Comparative Examples 1 to 5. Table 2 (continued) [Table 4] shows the compositions, molding conditions, and evaluations of the molded products of Comparative Examples 6 to 9. Table 2 (continued) [Table 5] shows Comparative Example 1
The compositions, molding conditions, and evaluations of the molded articles of 0 to 12 were shown.

[0085]

[Table 1]

[0086]

[Table 2]

[0087]

[Table 3]

[0088]

[Table 4]

[0089]

[Table 5]

[0090]

According to the present invention, a polylactic acid-based heat-resistant resin composition having excellent heat resistance and moldability in addition to the inherently excellent decomposability inherent to polylactic acid, and a molded product thereof Can be provided. According to the present invention, it can be applied to a normal molding technology with high productivity, and
Thus, a polylactic acid-based heat-resistant resin composition that can produce a molded product having excellent heat resistance and moldability can be provided. According to the present invention, during molding, injection molding can be performed at a mold temperature of Tg (glass transition temperature) or below or near room temperature. Immediately after molding, the crystallization speed of the molded product is high and the crystallinity is sufficient. Therefore, the heat-resistant resin has excellent heat resistance, and exhibits the function of preventing the polymer component in the molded product from deteriorating and the molded product from becoming brittle when the molded product is used. A composition can be provided.

Here, the “ordinary molding technique with high productivity” is defined as a special low-productivity molding technique such as heat treatment in a mold requiring a long molding cycle at a high mold temperature. Rather, it means normal molding technology with high productivity that requires only a short molding cycle at normal mold temperature. Also, "normal molding technology with high productivity"
Technology that uses a normal molding machine in a molding cycle equivalent to a general-purpose resin (for example, a molding cycle equivalent to a polypropylene resin) without using a special method such as annealing (heat treatment) in a mold. Also means.

Here, “excellent heat resistance” means that the molded product has a heat resistance temperature of 100 to 130 ° C. The term "excellent heat resistance" also means that the molded product is suitable for use at a high temperature, such as a container for pouring hot water. Further, “excellent heat resistance” also means that the molded product has a high degree of crystallinity.

Continuing on the front page (72) Inventor Tomoyuki Nakata 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsui Toatsu Chemical Co., Ltd. (72) Inventor Kazuhiko 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemicals (72) Inventor Masanobu Amioka 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (13)

[Claims] 1. The polymer composition component (A) comprises (a)
1) 75 to 25% by weight of polylactic acid and (a2) 25 to 75% by weight of an aliphatic polyester having a melting point of 100 to 250 ° C. other than polylactic acid, and a crystalline inorganic filler component (B) And those containing 10% by weight or more of crystalline SiO ₂ , and the component (A) 10
A heat-resistant resin composition, wherein component (B) is 0.1 to 70 parts by weight with respect to 0 parts by weight. 2. The heat-resistant resin composition according to claim 1, wherein “(a1) polylactic acid” is a lactic acid homopolymer. 3. The method according to claim 3, wherein (a1) polylactic acid is (a1-
1) Lactic acid homopolymer, (a1-2) Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid, (a1-3) 50
(A1-4) 50% by weight or more of lactic acid and 50% by weight or less of lactic acid; and (a1-4) 50% by weight or less of lactic acid. Other than hydroxycarboxylic acid and copolylactic acid produced from an aliphatic polyhydric alcohol and an aliphatic polybasic acid, at least one selected from the group consisting of:
The heat-resistant resin composition according to claim 1. 4. (a1-2) Copolylactic acid formed from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid; (a1-3) 50% by weight or more of lactic acid; Copolylactic acid produced from an aliphatic polyhydric alcohol and an aliphatic polybasic acid in an amount of not more than
-4) 50% by weight or more of lactic acid, and 50% by weight or less of hydroxycarboxylic acid other than lactic acid and copolylactic acid produced from aliphatic polyhydric alcohol and aliphatic polybasic acid "are block copolymers. Item 4. A heat-resistant resin composition according to item 3. 5. “(a1-2) Copolylactic acid formed from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid”, wherein “hydroxycarboxylic acid other than lactic acid” is caproic acid. The heat-resistant resin composition according to claim 3. 6. “(a1-3) Copolylactic acid produced from 50% by weight or more of lactic acid, 50% by weight or less of aliphatic polyhydric alcohol and aliphatic polybasic acid”, “Aliphatic polyhydric alcohol and fat” The heat-resistant resin composition according to any one of claims 3 to 5, wherein the "group polybasic acid" is "1,4-butanediol and succinic acid". 7. “(a1-2) Copolylactic acid formed from 50% by weight or more of lactic acid and 50% by weight or less of a hydroxycarboxylic acid other than lactic acid” is defined as “(a1-2) 50% by weight or more of polylactic acid. The heat-resistant resin composition according to claim 4, which is a "block copolymer comprising a lactic acid segment and 50% by weight or less of a polycaproic acid segment." 8. “(a1-3) Copolylactic acid produced from 50% by weight or more of lactic acid and 50% by weight or less of an aliphatic polyhydric alcohol and an aliphatic polybasic acid” is “(a1-3)
The heat-resistant resin composition according to claim 4, which is a "block copolymer comprising 50% by weight or more of a polylactic acid segment and 50% by weight or less of a polybutylene succinate segment". 9. (a2) The melting point of polylactic acid other than 10
(A2-1) aliphatic polyester at 0 to 250 ° C.
Polyethylene oxalate, (a2-2) polybutylene oxalate, (a2-3) polyneopentyl glycol oxalate, (a2-4) polyethylene succinate, (a2-5) polybutylene succinate, (a2-6) Polyglycolic acid, (a2-7)
Polyhydroxybutyric acid and (a2-
8) The heat-resistant resin composition according to any one of claims 1 to 8, wherein the composition is at least one selected from the group consisting of a copolymer of β-hydroxybutyric acid and β-hydroxyvaleric acid. 10. (a2) The melting point of other than polylactic acid is 1
The heat-resistant resin composition according to any one of claims 1 to 8, wherein the "aliphatic polyester at 00 to 250C" is a polybutylene succinate. 11. The method according to claim 11, wherein the (a1) polylactic acid is (a1-
1) Lactic acid homopolymer, (a1-2) copolylactic acid formed from 50% by weight or more of lactic acid and 50% by weight or less of 6-hydroxycaproic acid, and (a1-3) 50
The heat-resistant resin composition according to claim 1, wherein the resin composition is at least one selected from the group consisting of copolylactic acid formed from lactic acid of not less than 50% by weight and 1,4-butanediol and not less than 50% by weight of succinic acid. . 12. (B) A crystalline inorganic filler component containing at least 10% by weight of crystalline SiO _2.
Is at least one selected from the group consisting of talc, kaolin, clay and kaolinite, the heat-resistant resin composition according to any one of claims 1 to 11. 13. A heat-resistant resin obtained from the heat-resistant resin composition according to claim 1, having a heat-resistant temperature of 100 to 1.
Molded product at 30 ° C.