JP5277407B2 - Nucleating agent for polylactic acid and polylactic acid resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nucleating agent for polylactic acid promoting crystallization of polylactic acid and improving heat resistance and moldability, and a polylactic acid resin composition using the nucleating agent. <P>SOLUTION: When nicotinic acid hydrazide is reacted with sebacic acid dichloride, dihydrazide (II) shown in figure is obtained. When a small amount of the dihydrazide (II) is added to polylactic acid, excellent crystallization promotion action is exhibited, and crystallization temperature is increased. Therefore, heat resistance and moldability of a polylactic acid resin can be improved. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a nucleating agent for polylactic acid capable of promoting crystallization of polylactic acid and improving heat resistance and moldability, and a polylactic acid resin composition using the same.

  In recent years, from the viewpoint of environmental protection, biodegradable resins that can be degraded by microorganisms in the natural environment have attracted attention, and various biodegradable resins such as polylactic acid, polycaprolactone, polybutylene succinate, and polyethylene succinate. Has been put to practical use. Among them, polylactic acid has excellent mechanical properties such as toughness and hardness equivalent to hard vinyl chloride resin, and also has transparency, so it is practically used among biodegradable resins. Is progressing.

  However, polylactic acid has low heat resistance, and, for example, when used as a packaging container, there is a problem that hot water cannot be added or heated in a microwave oven. For this reason, the cooling rate of the metal mold | die at the time of shaping | molding is made slow, or annealing treatment is performed after shaping | molding, crystallinity degree is raised and heat resistance is made | formed. However, with such a method, the molded product takes time and effort, and as a result, the manufacturing cost of the molded product increases.

  For this reason, a nucleating agent (sometimes referred to as a crystallization agent) is added to the polylactic acid resin to promote the crystallization of polylactic acid or to lower the crystallization temperature. There are attempts to solve. As such a nucleating agent, for example, calcium lactate (Patent Document 1), lactate, benzoate (Patent Document 2) and the like have been reported. However, these compounds are said to have a low crystallization-promoting action and a small effect of improving heat resistance and impact resistance (Patent Document 3).

  Patent Document 4 states that by adding polyglycolic acid and / or a derivative thereof to polylactic acid as a nucleating agent, the crystallization speed can be increased and the injection molding cycle can be shortened. Furthermore, in Patent Documents 5 to 7, when a molded body excellent in crystallinity, transparency and heat resistance is obtained by mixing an aromatic or aliphatic carboxylic acid amide compound with polylactic acid or aliphatic polyester. Have been described.

  However, according to the description in Patent Document 3, such effects cannot be confirmed for the nucleating agents described in Patent Documents 4 to 7. As a new nucleating agent, it is described that a chain amide, a cyclic amide, a chain hydrazide and a cyclic hydrazide exhibit an excellent crystallization promoting effect.

  In Patent Document 8, amide compound or hydrazide compound is used as a nucleating agent, and a phenolic antioxidant is used in combination, so that a crystallization temperature of 125 ° C. and a crystallization heat amount of 40 J / g or more are obtained. .

No. 5-504731 (International Publication No. 90/001521 pamphlet) JP-T 6-504799 JP-A-8-193165 JP-A-4-220456 JP-A-9-278991 Japanese Patent Laid-Open No. 10-87975 JP-A-11-5849 JP 2004-352873 A

  The present invention has been made in view of the above-described conventional problems, and is capable of promoting crystallization of polylactic acid and improving heat resistance and moldability, and polylactic acid using the same. It is an object to provide a resin composition.

  The inventors have conducted intensive studies on structural requirements that have particularly excellent effects on hydrazine compounds that are conventionally known as nucleating agents for polylactic acid resins. As a result, it was discovered that nicotinic acid hydrazide derivatives and isonicotinic acid hydrazide derivatives have an excellent effect as a nucleating agent for polylactic acid resins, and the present invention has been completed.

That is, the nucleating agent for polylactic acid-based resin according to the first aspect of the present invention is characterized by including at least one compound having the following functional groups (a) to (d).

  According to the test results of the inventors, when the compounds having the functional groups (a) to (d) are added to polylactic acid, the crystallization temperature and the heat of crystallization can be remarkably increased. Formability can be improved. Such an effect is obtained by the compound having a functional group obtained by substituting the pyridine ring in the functional groups (a) to (d) with a benzene ring (described in Patent Document 8 as a polylactic acid-based nucleating agent compound). It was better than the effect. This is presumably because the pyridine ring has basic nitrogen, and this nitrogen forms a hydrogen bond with polylactic acid, so that the crystallization temperature rises.

  The nucleating agent for polylactic acid-based resin according to the first aspect of the present invention is easily and easily reacted with an electrophilic reagent such as carboxylic acid chloride or isocyanate using nicotinic acid hydrazide or isonicotinic acid hydrazide as a raw material. It can be obtained quantitatively. In addition, various variations of compounds can be obtained by changing the structure of the electrophilic reagent such as carboxylic acid chloride.

The nucleating agent for polylactic acid-based resin according to the second aspect of the present invention is a compound represented by any one of the following structural formulas (1) to (4) (wherein R is an alkyl group which may be branched). Or an aryl group which may have a substituent).

The nucleating agent for polylactic acid-based resin according to the third aspect of the present invention comprises at least one compound represented by the following structural formulas (5) to (10) (where n is an integer of 1 to 20). Included.

The nucleating agent for polylactic acid-based resin according to the fifth aspect of the present invention includes at least one compound represented by the following structural formulas (11) to (17).

The nucleating agent for polylactic acid-based resin according to the sixth aspect of the present invention comprises at least one compound represented by the following structural formulas (18) to (27) (where n is an integer of 2 to 10). Included.

The nucleating agent for polylactic acid-based resin according to the seventh aspect of the present invention is a compound represented by the following structural formula (28) or (29) (wherein R and X are hydrogen, an alkyl group, a halogen group, or a nitro group. , Which represents a methoxy group).

  By adding the nucleating agent for polylactic acid resin of the present invention to the polylactic acid resin, the heat resistance and moldability of the polylactic acid resin are excellent. That is, the polylactic acid resin composition of the present invention is characterized by containing at least one of the nucleating agents for polylactic acid resins according to claims 1 to 7.

  The nucleating agent for polylactic acid resin of the present invention can be used by adding to polylactic acid or polylactic acid resin. The polylactic acid may be synthesized by the user himself, but it is also possible to use a commercially available product because it is easily available. Specifically, Nature Works (registered trademark) manufactured by Cargill-DOW, U'z (registered trademark) manufactured by Toyota Motor Corporation, TONE (registered trademark) manufactured by UCC, manufactured by Shimadzu Corporation Lacty (registered trademark), Terramac (registered trademark) manufactured by Unitika Ltd., Lacia (registered trademark) manufactured by Mitsui Chemicals Co., Ltd., Lactron (registered trademark) manufactured by Kanebo Gosei Co., Ltd. ), Plastarch (registered trademark) manufactured by Kuraray Co., Ltd., Palgreen (registered trademark) manufactured by Tosero Co., Ltd., and the like.

  Moreover, polylactic acid means the polymer | macromolecule which L-lactic acid and / or D-lactic acid have superposed | polymerized by the ester bond substantially. Here, “substantially” means that other monomer units other than L-lactic acid or D-lactic acid may be included to the extent that the effects of the present invention are not impaired.

  In addition, the polylactic acid resin composition of the present invention can be subjected to various modifications by adding secondary additives as necessary within a range that does not hinder achievement of the problems of the invention. Examples of secondary additives include plasticizers, antioxidants, flame retardants, UV absorbers, colorants, pigments, antibacterial agents, stabilizers, electrostatic agents, nucleating materials, various fillers, and other similarities. Can be mentioned.

５００ｍｌの三口フラスコにニコチン酸ヒドラジド１３．７ｇ（０．１０ｍｏｌ）とトリエチルアミン１２．１ｇ（０．１２ｍｏｌ）、３００ｍｌのＤＭＦを入れ、５０ｍｌのＤＭＦに溶かしたサクシニルクロライド７．８ｇ（０．０５０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ジヒドラジド（Ｉ）の粗生成物を得た。（収量１６．１g、収率 ９０％）再結晶はメタノールより行なった。（融点２３５℃） Examples in which the present invention is further embodied will be described below in comparison with comparative examples.
Example 1
Synthesis of dihydrazide (I)

In a 500 ml three-necked flask, 13.7 g (0.10 mol) of nicotinic acid hydrazide, 12.1 g (0.12 mol) of triethylamine, and 300 ml of DMF were added, and 7.8 g (0.050 mol) of succinyl chloride dissolved in 50 ml of DMF. It was dripped at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of dihydrazide (I). (Yield 16.1 g, Yield 90%) Recrystallization was performed from methanol. (Melting point 235 ° C)

５００ｍｌの三口フラスコにニコチン酸ヒドラジド１１．０ｇ（０．０８０ｍｏｌ）とトリエチルアミン９．７ｇ（０．０９６ｍｏｌ）と２５０ｍｌのＤＭＦを入れ、５０ｍｌのＤＭＦに溶かしたセバシン酸クロライド９．６ｇ（０．０４０ｍｏｌ）を０°Ｃで滴下した。滴下終了後、そのままの温度で５時間反応させ、反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ジヒドラジド（ＩＩ）の粗生成物を得た（収量１７．９ｇ、収率９５%）。再結晶はメタノールより行なった（融点２１７℃）。 (Example 2)
Synthesis of dihydrazide (II)

A 500 ml three-necked flask was charged with 11.0 g (0.080 mol) of nicotinic acid hydrazide, 9.7 g (0.096 mol) of triethylamine and 250 ml of DMF, and 9.6 g (0.040 mol) of sebacic acid chloride dissolved in 50 ml of DMF. Was added dropwise at 0 ° C. After completion of the dropwise addition, the reaction was allowed to proceed at the same temperature for 5 hours. After the reaction was completed, the reaction solution was poured into ice water. The produced precipitate was filtered to obtain a crude product of dihydrazide (II) (yield 17.9 g, yield 95%). Recrystallization was performed from methanol (melting point 217 ° C.).

５００ｍｌの三口フラスコにイソニコチン酸ヒドラジド１１．０ｇ（０．０８０ｍｏｌ）とトリエチルアミン９．７ｇ（０．０９６ｍｏｌ）と、２５０ｍｌのＤＭＦとを入れ、５０ｍｌのＤＭＦに溶かしたセバシン酸クロライド９．６ｇ（０．０４０ｍｏｌ）を０°Ｃで滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ジヒドラジド（ＩＩＩ）の粗生成物を得た。（収量１７．３ｇ、収率９１%）再結晶はメタノールより行なった。（融点２２０℃） (Example 3)
Synthesis of dihydrazide (III)

A 500 ml three-necked flask was charged with 11.0 g (0.080 mol) of isonicotinic acid hydrazide, 9.7 g (0.096 mol) of triethylamine and 250 ml of DMF, and 9.6 g of sebacic acid chloride dissolved in 50 ml of DMF (0 .040 mol) was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of dihydrazide (III). (Yield 17.3 g, Yield 91%) Recrystallization was performed from methanol. (Melting point 220 ° C)

５００ｍｌlの三口フラスコにニコチン酸ヒドラジド１３．７ｇ（０．１０ｍｏｌ）とトリエチルアミン１２．１ｇ（０．１２ｍｏｌ）、３００ｍｌのＤＭＦを入れ、５０ｍｌのＤＭＦに溶かしたテレフタロイルクロライド１０．２ｇ（０．０５０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ジヒドラジド（ＩＶ）の粗生成物を得た。（収量１７．３ｇ、収率８６%）再結晶はメタノールより行なった。（融点３２５℃） Example 4
Synthesis of dihydrazide (IV)

A 500 ml three-necked flask is charged with 13.7 g (0.10 mol) of nicotinic acid hydrazide, 12.1 g (0.12 mol) of triethylamine, and 300 ml of DMF, and 10.2 g (0.050 mol) of terephthaloyl chloride dissolved in 50 ml of DMF. ) Was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of dihydrazide (IV). (Yield 17.3 g, Yield 86%) Recrystallization was performed from methanol. (Melting point 325 ° C)

３００ｍｌの三口フラスコにニコチン酸ヒドラジド５．５ｇ（０．０４０ｍｏｌ）とトリエチルアミン４．９ｇ（０．０４８ｍｏｌ）、１５０ｍｌのＤＭＦを入れ、５０ｍｌのＤＭＦに溶かしたイソフタロイルクロライド４．１g（０．０２０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ジヒドラジド（Ｖ）の粗生成物を得た。（収量７．１ｇ、収率８８%）再結晶はメタノールより行なった。（融点２９１℃） (Example 5)
Synthesis of dihydrazide (V)

A 300 ml three-necked flask was charged with 5.5 g (0.040 mol) of nicotinic acid hydrazide, 4.9 g (0.048 mol) of triethylamine and 150 ml of DMF, and 4.1 g (0.020 mol) of isophthaloyl chloride dissolved in 50 ml of DMF. ) Was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The produced precipitate was filtered to obtain a crude product of dihydrazide (V). (Yield 7.1 g, 88% yield) Recrystallization was performed from methanol. (Melting point 291 ° C)

３００ｍｌの三口フラスコにニコチン酸ヒドラジド５．５ｇ（０．０４０ｍｏｌ）とトリエチルアミン６．１ｇ（０．０６０ｍｏｌ）、１００ｍｌのＤＭＦを入れ、５０ｍｌのＤＭＦに溶かしデカノイルクロライド７．６ｇ（０．０４０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ジヒドラジド（ＶＩ）の粗生成物を得た。（収量９．６ｇ、収率８２%）再結晶は水−メタノールより行なった。（融点１１７℃） (Example 6)
Synthesis of dihydrazide (VI)

In a 300 ml three-necked flask, 5.5 g (0.040 mol) of nicotinic acid hydrazide, 6.1 g (0.060 mol) of triethylamine, and 100 ml of DMF were dissolved in 50 ml of DMF and 7.6 g (0.040 mol) of decanoyl chloride was dissolved. It was dripped at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The produced precipitate was filtered to obtain a crude product of dihydrazide (VI). (Yield 9.6 g, Yield 82%) Recrystallization was performed from water-methanol. (Melting point 117 ° C)

３００ｍｌの三口フラスコにニコチン酸ヒドラジド６．９ｇ（０．０５０ｍｏｌ）とトリエチルアミン６．１ｇ（０．０６０ｍｏｌ）と１５０ｍｌのＤＭＦとを入れ、５０ｍｌのＤＭＦに溶かしたベンゾイルクロライド７．０ｇ（０．０５０ｍｏｌ）を０°Ｃで滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ヒドラジド（ＶＩＩ）の粗生成物を得た。（収量１１．８ｇ、収率９８%）再結晶はメタノールより行なった。（融点２３９℃） (Example 7)
Synthesis of hydrazide (VII)

A 300 ml three-necked flask was charged with 6.9 g (0.050 mol) of nicotinic acid hydrazide, 6.1 g (0.060 mol) of triethylamine and 150 ml of DMF, and 7.0 g (0.050 mol) of benzoyl chloride dissolved in 50 ml of DMF. Was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of hydrazide (VII). (Yield 11.8 g, yield 98%) Recrystallization was performed from methanol. (Melting point 239 ° C)

３００ｍｌの三口フラスコにイソニコチン酸ヒドラジド６．９ｇ（０．０５０ｍｏｌ）とトリエチルアミン６．１ｇ（０．０６０ｍｏｌ）と１５０ｍｌのＤＭＦとを入れ、５０ｍｌのＤＭＦに溶かしたベンゾイルクロライド７．０ｇ（０．０５０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ヒドラジド（ＶＩＩＩ）の粗生成物を得た。（収量１１．５ｇ、収率９６％）再結晶はメタノールより行なった。（融点２３０℃） (Example 8)
Synthesis of hydrazide (VIII)

A 300 ml three-necked flask was charged with 6.9 g (0.050 mol) of isonicotinic acid hydrazide, 6.1 g (0.060 mol) of triethylamine, and 150 ml of DMF, and 7.0 g (0.050 mol) of benzoyl chloride dissolved in 50 ml of DMF. ) Was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of hydrazide (VIII). (Yield 11.5 g, yield 96%) Recrystallization was performed from methanol. (Melting point 230 ° C)

３００ｍｌの三口フラスコにニコチン酸ヒドラジド５．５ｇ（０．０４０ｍｏｌ）とトリエチルアミン６．１ｇ（０．０６０ｍｏｌ）、１００ｍｌのＤＭＦを入れ、１００ｍｌのＤＭＦに溶かしたニコチノイルクロライド塩酸塩７．１ｇ（０．０４０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ヒドラジド（ＩＸ）の粗生成物を得た。（収量７．６ｇ、収率７８%）再結晶はメタノールより行なった。（融点２２９℃） Example 9
Synthesis of dihydrazide (IX)

In a 300 ml three-necked flask, 5.5 g (0.040 mol) of nicotinic acid hydrazide, 6.1 g (0.060 mol) of triethylamine and 100 ml of DMF were added, and 7.1 g (0. 0. 0) of nicotinoyl chloride dissolved in 100 ml of DMF. 040 mol) was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of hydrazide (IX). (Yield 7.6 g, Yield 78%) Recrystallization was performed from methanol. (Melting point 229 ° C)

３００ｍｌの三口フラスコにニコチン酸ヒドラジド５．５ｇ（０．０４０ｍｏｌ）)とトリエチルアミン６．１ｇ（０．０６０ｍｏｌ）、１００ｍｌのＤＭＦを入れ、１００ｍｌのＤＭＦに溶かしたイソニコチノイルクロライド塩酸塩７．１ｇ（０．０４０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ヒドラジド（Ｘ）の粗生成物を得た。（収量７．３ｇ、収率７５%）再結晶は水−メタノールより行なった。（融点２２７ ℃） (Example 10)
Synthesis of hydrazide (X)

Nicotinic acid hydrazide (5.5 g (0.040 mol)), triethylamine 6.1 g (0.060 mol) and 100 ml of DMF were placed in a 300 ml three-necked flask, and 7.1 g of isonicotinoyl chloride hydrochloride dissolved in 100 ml of DMF ( 0.040 mol) was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of hydrazide (X). (Yield 7.3 g, Yield 75%) Recrystallization was performed from water-methanol. (Melting point 227 ° C)

３００ｍｌの三口フラスコにイソニコチン酸ヒドラジド４．１ｇ（０．０３０ｍｏｌ）とトリエチルアミン４．６ｇ（０．０４５ｍｏｌ）、１００ｍｌのＤＭＦを入れ、１００ｍｌのＤＭＦに溶かしたイソニコチノイルクロライド塩酸塩５．３ｇ（０．０３０ｍｏｌ）を０℃で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、反応溶液を氷水中に投入した。生成した沈殿物をろ過し、ヒドラジド（ＸＩ）の粗生成物を得た。（収量 ５．４ｇ、収率７５%）再結晶はメタノールより行なった。（融点２６６ ℃） (Example 11)
Synthesis of hydrazide (XI)

A 300 ml three-necked flask was charged with 4.1 g (0.030 mol) of isonicotinic acid hydrazide, 4.6 g (0.045 mol) of triethylamine, and 100 ml of DMF, and 5.3 g of isonicotinoyl chloride hydrochloride dissolved in 100 ml of DMF ( 0.030 mol) was added dropwise at 0 ° C. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After completion of the reaction, the reaction solution was poured into ice water. The generated precipitate was filtered to obtain a crude product of hydrazide (XI). (Yield 5.4 g, 75% yield) Recrystallization was performed from methanol. (Melting point: 266 ° C)

５０ｍｌの三口フラスコにニコチン酸ヒドラジド２．７ｇ（０．０２０ｍｏｌ）と１０ｍｌのＤＭＦを入れ、１０ｍｌのＤＭＦに溶かしたヘキサメチレンジイソシアネート１．７ｇ（０．０１０ｍｏｌ）を室温で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、生成した沈殿物をろ過し、セミカルバジド（ＸＩＩ）粗生成物を得た。（収量４．１ｇ、収率９２%）再結晶はメタノールより行なった。（融点２０７℃） (Example 12)
Synthesis of semicarbazide (XII)

In a 50 ml three-necked flask, 2.7 g (0.020 mol) of nicotinic acid hydrazide and 10 ml of DMF were placed, and 1.7 g (0.010 mol) of hexamethylene diisocyanate dissolved in 10 ml of DMF was added dropwise at room temperature. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After the reaction was completed, the generated precipitate was filtered to obtain a crude semicarbazide (XII) product. (Yield 4.1 g, yield 92%) Recrystallization was performed from methanol. (Melting point 207 ° C)

５０ｍｌの三口フラスコにニコチン酸ヒドラジド２．７ｇ（０．０２０ｍｏｌ）と１０ｍｌのＤＭＦを入れ、１０ｍｌのＤＭＦに溶かしたヘキサメチレンジイソシアネート２．５ｇ（０．０１０ｍｏＬ）を室温で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、生成した沈殿物をろ過し、セミカルバジド（ＸＩＩＩ）粗生成物を得た。（収量５．１ｇ、収率９６%）再結晶はメタノールより行なった。（融点２４９℃） (Example 13)
Synthesis of semicarbazide (XIII)

In a 50 ml three-necked flask, 2.7 g (0.020 mol) of nicotinic acid hydrazide and 10 ml of DMF were placed, and 2.5 g (0.010 mol) of hexamethylene diisocyanate dissolved in 10 ml of DMF was added dropwise at room temperature. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After the reaction was completed, the generated precipitate was filtered to obtain a crude semicarbazide (XIII) product. (Yield 5.1 g, yield 96%) Recrystallization was performed from methanol. (Melting point 249 ° C)

５０ｍｌの三口フラスコにニコチン酸ヒドラジド１．４ｇ（０．０１０ｍｏｌ）と５ｍｌのＤＭＦを入れ、５ｍｌのＤＭＦに溶かしたフェニルイソシアネート１．２ｇ（０．０１０ｍｏｌ）を室温で滴下した。滴下終了後、そのままの温度で５時間反応した。反応終了後、生成した沈殿物をろ過し、セミカルバジド（ＸＩＶ）粗生成物を得た。（収量２．４ｇ、収率９４%）再結晶はメタノールより行なった。（融点２２８℃） (Example 14)
Synthesis of semicarbazide (XIV)

A 50 ml three-necked flask was charged with 1.4 g (0.010 mol) of nicotinic acid hydrazide and 5 ml of DMF, and 1.2 g (0.010 mol) of phenyl isocyanate dissolved in 5 ml of DMF was added dropwise at room temperature. After completion of the dropping, the reaction was carried out at the same temperature for 5 hours. After the reaction was completed, the generated precipitate was filtered to obtain a crude semicarbazide (XIV) product. (Yield 2.4 g, 94% yield) Recrystallization was performed from methanol. (Melting point 228 ° C)

<Preparation of polylactic acid resin composition>
Example 1
A polylactic acid resin composition in which the dihydrazide (I) was added to polylactic acid was prepared as follows. That is, after polylactic acid (Terramac T-4000 manufactured by Unitika Co., Ltd.) was dried at 100 ° C. for 4 hours, polylactic acid and dihydrazide (I) were mixed at a weight ratio of 98: 2. This mixture was melt-extruded at 190 ° C. with a biaxial extrusion heating kneader to obtain a polylactic acid resin composition of Example 1.

(Example 2 to Example 10)
In the same manner as in Example 1, hydrazides (II) to (XI) and semicarbazides (XII) to (XIV) were kneaded with polylactic acid at a weight ratio of 98: 2, A lactic acid resin composition was prepared.

(Comparative Example 1)
A comparative example 1 was prepared by adding nothing to the polylactic acid used as a raw material in Examples 1-14.

<Evaluation>
1) Measurement of differential scanning calorimetry (DSC) About the polylactic acid resin composition of the said Example 1- Example 14 and the polylactic acid of the comparative example 1, using a differential scanning calorimeter (Seiko electronic product number DSC200 heat flux system). Differential scanning calorimetry (DSC) was measured. The results are shown in Table 1 and FIGS.

As shown in FIG. 1, in the polylactic acid resin of Comparative Example 1 to which no nucleating agent was added, no peak indicating the crystallization temperature was observed, whereas the nucleating examples of Examples 2, 3, 7, and 8 were observed. In the polylactic acid resin composition to which the agent was added, a clear peak was observed, and the effect of promoting crystallization was confirmed. In addition, clear crystallization peaks were also observed in Examples 1, 4, 5, 6, 9, 10, 11, 12, 13, and 14 whose DSC curves are not shown.
The crystallization temperatures of Examples 2, 3, 7, and 8 were particularly high at 127.8 ° C. to 137.4 ° C., and showed the highest crystallization temperature among the conventional polylactic acid resin nucleating agents described above. It was superior to the data of the polylactic acid resin composition described in paragraph No. 0096 of Patent Document 8 (crystallization temperature 126 ° C., crystallization heat amount −44).
From the above results, it was found that if the nucleating agent for polylactic acid of the present invention is added to polylactic acid, crystallization of polylactic acid can be promoted and heat resistance and moldability can be improved.

2) Measurement of temperature-deflection curve The temperature-deflection curve was measured about the board | plate material which added the nucleating agent for polylactic acids of this invention to polylactic acid. In the test, hydrazide (II) produced in Example 2 above and a commercially available nucleating agent for polylactic acid (PPA-Zn manufactured by Nissan Chemical Co., Ltd.) were used as a comparison, and a sample was prepared according to the following procedure. That is, after polylactic acid (Unitika Terramac T-4000) is dried at 100 ° C. for 4 hours, 500 g is measured. And 5g of hydrazide (II) was added as a polylactic acid nucleating agent, and it melt-extruded with the twin-screw extruder (Technobel Co., Ltd. KZW15-30TGN) at the extrusion temperature of 200 degreeC, and prepared the pellet. The pellets thus obtained were molded using an injection molding machine (SE18S manufactured by Sumitomo Heavy Industries, Ltd.) at a molding temperature of 200 ° C. to obtain a plate material of 80 mm × 10 mm × 4 mm. Moreover, the board | plate material which consists of polylactic acid which did not add the nucleating agent for polylactic acids was also produced.

The temperature-deflection curve was measured using a load-deflection measuring device (3M-2 manufactured by Toyo Seiki). The deflection temperature under load (DTUL) was determined by the low load method (0.45 MPa) according to JIS K7191-1, 2 (ISO75). ) And the flatwise method. The measurement sample was annealed at 120 ° C. for 2 minutes in advance. The results are shown in FIG.
From this figure, the plate material made of polylactic acid to which no nucleating agent for polylactic acid was added reached the deflection temperature under load at 58.5 ° C., and a commercially available nucleating agent for polylactic acid (PPA-Zn made by Nissan Chemical Co., Ltd.) ), The deflection temperature under load was 105 ° C., whereas the test piece added with hydrazide (II) produced in Example 2 did not reach the reference deflection amount even at 140 ° C., and was extremely heat resistant. It turned out that it is excellent in property.

  The present invention is not limited to the description of the embodiments of the invention. Various modifications may be included in the present invention as long as those skilled in the art can easily conceive without departing from the description of the scope of claims.

  The polylactic acid-based resin composition of the present invention can be used for various applications such as packaging materials, medical materials, industrial materials, industrial products, containers and the like. Specifically, it can be used for films, sheets, coated papers, blow molded articles, injection molded articles, extruded molded articles, fibers, nonwoven fabrics, packaging materials, and the like. Moreover, the nucleating agent for polylactic acid-type resin of this invention can be used suitably for a polylactic acid-type resin composition.

It is a DSC curve of Comparative Example 1 (polylactic acid alone). 2 is a DSC curve of the polylactic acid resin composition of Example 2. 3 is a DSC curve of the polylactic acid resin composition of Example 3. 2 is a DSC curve of the polylactic acid resin composition of Example 7. 2 is a DSC curve of the polylactic acid resin composition of Example 8. It is a figure which shows the measurement result of a temperature-deflection curve.

Claims (5)

A nucleating agent for polylactic acid-based resin, comprising at least one compound represented by the following structural formulas (5) to (10) (wherein n is an integer of 1 to 20).

A nucleating agent for polylactic acid-based resin comprising at least one compound represented by the following structural formulas (11) and (13) to (17).

A nucleating agent for polylactic acid-based resin, comprising at least one compound represented by the following structural formulas (18) to (27) (where n is an integer of 2 to 10).

Poly, characterized in that it contains at least one compound represented by the following structural formula (28) or (29) (wherein R and X represent hydrogen, an alkyl group, a halogen group, a nitro group, or a methoxy group). Nucleating agent for lactic acid resin.

A polylactic acid resin composition comprising at least one nucleating agent for polylactic acid resin according to any one of claims 1 to 4.

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